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1.
Ecotoxicol Environ Saf ; 208: 111631, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396151

RESUMO

This study was conducted to assess heavy metals in the overlying water and sediments of Luhun Reservoir, Henan Province, China, which is positioned downstream from a molybdenum (Mo) mining area. The pollution indexes indicated that deposition of all metals may have been affected by the mining area. The single element pollution factor (Pi) of Mo was the highest among all heavy metals, with a mean value of 2.05. However, the sediments were subject to long-term accumulation of metals, particularly Mo, Cd, Pb, and Zn, which originated from anthropogenic sources. The mean individual element potential ecological risk index values for Cd were above 385, while the mean value comprehensive potential ecological risk index was 465, which indicates a high ecological risk. Moreover, the enriched heavy metals had different spatial distributions in the Luhun Reservoir sediments. Finally, Pearson correlation analysis indicated that the Pb was mainly affected by different anthropogenic sources and had no relationship with other metals, which suggests that the influence of mining area on heavy metal concentrations in the reservoir is difficult to disentangle.


Assuntos
Mineração , Molibdênio/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Sedimentos Geológicos/análise , Metais Pesados/análise , Medição de Risco
2.
Zhongguo Zhong Yao Za Zhi ; 46(9): 2142-2148, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34047114

RESUMO

Metallomics is a frontier interdisciplinary subject at its vigorous development stage. Its goal is to systematically study the content, distribution, chemical species, structural characteristics and functions of metal elements in biological system. It is also a comprehensive discipline to study the existing state and function of free or complex metal elements in life. Metallomics is an ideal tool to study the biological behavior of inorganic elements, which can be used to solve many problems in the research of mineral Chinese medicine(MCM). It provides a strong theoretical basis and technical support for the research of MCM. Its theory and methods provide re-ference and enlightenment for the in-depth study of MCM, and also provide new ideas and open up new ways for the research of MCM. The application of metallomics theory and methods in the research of MCM is of great significance to reveal the material basis and mec-hanism of MCM, promote the process of basic research on MCM, fully exploit and utilize medicinal mineral resources and carry forward the traditional MCM treasure in China. In this paper, we introduced the concept, academic development, research content and research methods of metallomics, and discussed the application prospects of metallomics in the analysis of inorganic element composition characteristics and quality control, material basis and mechanism of MCM, so as to provide reference for further researches on MCM.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , China , Minerais , Controle de Qualidade
3.
Zhongguo Zhong Yao Za Zhi ; 46(14): 3694-3704, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34402294

RESUMO

The effects of Chloriti Lapis on metal elements in plasma and lung tissue of acute exacerbation of chronic obstructive pulmonary disease( AECOPD) rats were studied. The rat AECOPD model with phlegm heat syndrome was established by smoking combined with Klebsiella pneumoniae infection. After the rats were treated by Chloriti Lapis,the contents of metal elements in plasma and lung tissue were determined by inductively coupled plasma-optical emission spectroscopy( ICP-OES) and inductively coupled plasma mass spectrometry( ICP-MS). The changes in the contents of metal elements were analyzed by SPSS 18. 0. Further,the correlations of differential metal elements( including Cu/Zn ratio) with differential metabolites in plasma,lung tissue and urine of AECOPD rats treated with Chloriti Lapis were analyzed. The results showed that Chloriti Lapis significantly up-regulated the contents of Fe,Al,Mn,Cu,Zn,Sn( P<0. 05),V,Co( P< 0. 01) and Cu/Zn ratio( P< 0. 05),and significantly down-regulated the contents of Ti( P< 0. 05)and Pb( P<0. 05) in the model rat plasma. It significantly increased the content of Be( P<0. 05) and decreased the contents of Mg,Ti and Al( P<0. 01) in model rat lung tissue. The element profiles of normal group,model group and Chloriti Lapis group can be well separated. Chloriti Lapis group and other groups were clustered into two categories. The taurine in plasma and phytosphingosine in lung tissue had the strongest correlations with differential metal elements. The Fe,Al,Mg,Be,Ti,V,Mn,Cu,Zn,Sn,and Co in Chloriti Lapis may directly or indirectly participate in the intervention of AECOPD rats. This group of metal elements may be the material basis of Chloriti Lapis acting on AECOPD rats,and reduce the Cu/Zn value in vivo. It was further confirmed that Chloriti Lapis could interfere with the metabolic pathways of taurine and hypotaurine in plasma and urine as well as the sphingolipid metabolism pathway in lung tissue of AECOPD rats. In addition,this study confirmed that long-term smoking can cause high-concentration Cd accumulation in the lung and damage the lung tissue.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Oligoelementos , Animais , Pulmão , Medicina Tradicional Chinesa , Minerais , Ratos , Análise Espectral , Oligoelementos/análise
4.
Zhongguo Zhong Yao Za Zhi ; 46(12): 3133-3143, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467705

RESUMO

To study the effect of mineral Chloriti Lapis on pulmonary metabolites and metabolic pathways in lung tissues of rats with acute exacerbation of chronic obstructive pulmonary disease(AECOPD). The AECOPD rat model of phlegm heat syndrome was replicated by the method of smoking combined with Klebsiella pneumoniae infection. Except for using UPLC-Q-TOF-MS analysis, SPSS 18.0, SIMCA 13.0 and other software were also used for statistical analysis. Through literature search and online database comparison, the differential metabolites were identified, and the possible metabolic pathways were analyzed. After 15 days of administration, PLS-DA analysis was carried out on lung tissue samples of rats in each group. The results showed that the metabolic profiles of lung tissues of rats in each group could be well separated, which indicated that Chloriti Lapis and aminophylline had significant intervention effect on the lung metabolic profile of rats with AECOPD. Moreover, the metabolic profile of Chloriti Lapis group was closer to that of control group, and the intervention effect was better than that of aminophylline group. As a result, 15 potential differential metabolites were identified: phytosphingosine, sphinganine, tetradecanoylcarnitine, L-palmitoylcarnitine, elaidic carnitine, lysoPC[18∶2(9Z,12Z)], lysoPC(16∶0), lysoPC[18∶1(9Z)], lysoPC(18∶0), stearic acid, lysoPC(15∶0), arachidonic acid, docosapentaenoic acid, linoleic acid and palmitic acid. Among them, Chloriti Lapis could significantly improve the levels of 10 differential metabolites of phytosphingosine, tetradecanoylcarnitine, L-palmitoylcarnitine, elaidic carnitine, lysoPC[18∶2(9Z,12Z)], lysoPC(16∶0), lysoPC[18∶1(9Z)], stearic acid, lysoPC(15∶0), and palmitic acid(P<0.05). The intervention effect of Chloriti Lapis group was better than that of aminophylline group. Analysis of metabolic pathways showed that there were 8 possible metabolic pathways that could be affected, and three of the most important metabolic pathways(pathway impact>0.1) were involved: linoleic acid metabolism, arachidonic acid metabolism, and sphingolipid metabolism. Chloriti Lapis had obvious intervention effects on lung tissue-related metabolites and metabolic pathways in rats with AECOPD, and the effect was better than that of aminophyllinne.


Assuntos
Medicina Tradicional Chinesa , Doença Pulmonar Obstrutiva Crônica , Animais , Pulmão , Metabolômica , Minerais , Ratos
5.
J Nat Prod ; 83(11): 3471-3475, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33180498

RESUMO

Penisarins A (1) and B (2), sesquiterpene coumarins with an unusual tricyclic sesquiterpene system, were isolated from endophytic Penicillium sp. KMU18029. Their structures were elucidated on the basis of spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Compound 2 showed significant cytotoxicities against two human cancer cell lines, HL-60 and SMMC-7721, with IC50 values of 3.6 ± 0.2 and 3.7 ± 0.2 µM, respectively.


Assuntos
Cumarínicos/isolamento & purificação , Penicillium/química , Sesquiterpenos/isolamento & purificação , Linhagem Celular Tumoral , Dicroísmo Circular , Cumarínicos/química , Cristalografia por Raios X , Humanos , Estrutura Molecular , Sesquiterpenos/química
6.
Zhongguo Zhong Yao Za Zhi ; 42(15): 2989-2994, 2017 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-29139268

RESUMO

Models were established in mice with warfarin sodium method, and their bleeding time and hemostasis time were measured by tail cutting method and slide method respectively. Rats were administered for 15 consecutive days to measure their recalcification time, plasma viscosity, platelet adhesion rate, platelet aggregation rate and other blood indexes. As compared with the blank group, the bleeding time was prolonged in model groupn(P<0.05). As compared with the model group, the results showed that the positive vitamin K, the leaching type water decoction and the sediment type decoction could significantly shorten the bleeding time (P<0.01); positive vitamin K significantly (P<0.01) shortened clotting time, and the leaching type water decoction, the sediment type water decoction and the sediment type powder could also shorten the clotting time (P<0.05). As compared with blank group, low dose, medium dose of leaching type water decoction, medium dose of powder, high dose of sediment type decoction and low dose of drug residues could reduce plasma viscosity (P<0.05), and high dose of leaching powder and low dose of water decoction could significantly reduce (P<0.01) plasma viscosity. As compared with blank group, Limonitum leaching type decoction high dose group could significantly reduce the platelet adhesion rate (P<0.05), while sediment type water decoction could significantly increase the platelet adhesion rate (P<0.05); the high dose of leaching type water decoction, high dose of drug residues, low dose of leaching type powder and low dose of drug residues could decrease the platelet aggregation rate (P<0.05), while high dose of leaching type water decoction and high dose of the powder could increase the platelet aggregation rate (P<0.05). Analysis of mineral compositions was conducted by polarized light microscopy and X-ray diffraction (XRD). The results of the both methods showed that Limonitum mineral compositions contained goethite, quartz, and kaolinite, and sedimentary type also contained illite and albite. Sediment type of Limonitum showed better hemostatic effect, which may be related to the high content of goethite and illite.


Assuntos
Medicamentos de Ervas Chinesas/química , Hemostáticos/farmacologia , Plumbaginaceae/química , Animais , Hemostasia , Camundongos , Minerais , Agregação Plaquetária , Ratos
7.
Molecules ; 21(12)2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-27941680

RESUMO

A series of novel hybrid compounds between benzofuran and N-aryl piperazine have been synthesized and screened in vitro for anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW-264.7 macrophages and for anticancer activity against three human tumor cell lines. The results demonstrated that derivative 16 not only had inhibitory effect on the generation of NO (IC50 = 5.28 µM), but also showed satisfactory and selective cytotoxic activity against human lung cancer line (A549) and gastric cancer cell (SGC7901) (IC50 = 0.12 µM and 2.75 µM, respectively), which was identified as the most potent anti-inflammatory and anti-tumor agent in this study.


Assuntos
Antineoplásicos , Benzofuranos , Neoplasias Pulmonares/tratamento farmacológico , Piperazinas , Neoplasias Gástricas/tratamento farmacológico , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Benzofuranos/síntese química , Benzofuranos/química , Benzofuranos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Óxido Nítrico/biossíntese , Piperazinas/síntese química , Piperazinas/química , Piperazinas/farmacologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
8.
J Ethnopharmacol ; 331: 118303, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38734390

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Realgar, a traditional mineral Chinese medicine, has been used in China for more than 2000 years. It has been recorded in many ancient and modern works that it has anti-cancer and anti-tumor effects. Of course, colon cancer is also within the scope of its treatment. Realgar needs to be processed into realgar decoction pieces by water grinding before being used for medicine. To ensure the consistency of efficacy and quality of realgar decoction pieces, modern methods need to be used for further quality control. AIM OF THE STUDY: The research of traditional mineral Chinese medicine is relatively difficult, and the related research is less. The purpose of this study is to control the quality of realgar decoction pieces by modern analytical technology and analyze its components. On this basis, its anti-colon cancer activity was discussed. MATERIALS AND METHODS: Several batches of realgar decoction pieces were analyzed by XRD, and the components of realgar decoction pieces were obtained. The quality control fingerprints of realgar decoction pieces were established by processing XRD spectra and similarity evaluation. Then, the effects of realgar decoction pieces on apoptosis of CT26 and HTC-116 cells were observed in vitro by Hoechst 33258 staining, flow cytometry, measurement of mitochondrial membrane potential and Western blot; In vivo, the mouse model of tumor-in-situ transplantation of colon cancer was established, and the related indexes were observed. RESULT: The explorations showed that the XRD Fourier fingerprints of realgar decoction pieces samples that had the same phase revealed 10 common peaks, respectively. The similarity evaluation of the established XRD Fourier fingerprint was greater than 0.900. We also demonstrated that realgar decoction pieces can promote apoptosis and inhibit tumor growth in colon cancer cells, its activating effect on p53 protein, and its safety when used within reasonable limits. CONCLUSION: The quality control of realgar decoction pieces by XRD is scientific and has the inhibitory effect on colon cancer, which has the development potential.


Assuntos
Apoptose , Neoplasias do Colo , Animais , Apoptose/efeitos dos fármacos , Camundongos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Humanos , Sulfetos/farmacologia , Sulfetos/uso terapêutico , Arsenicais/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Linhagem Celular Tumoral , Camundongos Endogâmicos BALB C , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Masculino , Controle de Qualidade , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico
9.
PLoS Negl Trop Dis ; 18(5): e0012163, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38713713

RESUMO

BACKGROUND: Toxoplasmosis affects a quarter of the world's population. Toxoplasma gondii (T.gondii) is an intracellular parasitic protozoa. Macrophages are necessary for proliferation and spread of T.gondii by regulating immunity and metabolism. Family with sequence similarity 96A (Fam96a; formally named Ciao2a) is an evolutionarily conserved protein that is highly expressed in macrophages, but whether it play a role in control of T. gondii infection is unknown. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we utilized myeloid cell-specific knockout mice to test its role in anti-T. gondii immunity. The results showed that myeloid cell-specific deletion of Fam96a led to exacerbate both acute and chronic toxoplasmosis after exposure to T. gondii. This was related to a defectively reprogrammed polarization in Fam96a-deficient macrophages inhibited the induction of immune effector molecules, including iNOS, by suppressing interferon/STAT1 signaling. Fam96a regulated macrophage polarization process was in part dependent on its ability to fine-tuning intracellular iron (Fe) homeostasis in response to inflammatory stimuli. In addition, Fam96a regulated the mitochondrial oxidative phosphorylation or related events that involved in control of T. gondii. CONCLUSIONS/SIGNIFICANCE: All these findings suggest that Fam96a ablation in macrophages disrupts iron homeostasis and inhibits immune effector molecules, which may aggravate both acute and chronic toxoplasmosis. It highlights that Fam96a may autonomously act as a critical gatekeeper of T. gondii control in macrophages.


Assuntos
Ferro , Macrófagos , Camundongos Knockout , Toxoplasma , Toxoplasmose , Animais , Macrófagos/imunologia , Macrófagos/parasitologia , Toxoplasma/imunologia , Toxoplasma/fisiologia , Camundongos , Ferro/metabolismo , Toxoplasmose/imunologia , Toxoplasmose/parasitologia , Toxoplasmose/genética , Camundongos Endogâmicos C57BL , Feminino
10.
Nat Commun ; 15(1): 7914, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256385

RESUMO

IgA antibodies play an important role in mucosal immunity. However, there is still no effective way to consistently boost mucosal IgA responses, and the factors influencing these responses are not fully understood. We observed that colonization with the murine intestinal symbiotic protozoan Tritrichomonas musculis (T.mu) boosted antigen-specific mucosal IgA responses in wild-type C57BL/6 mice. This enhancement was attributed to the accumulation of free arachidonic acid (ARA) in the intestinal lumen, which served as a signal to stimulate the production of antigen-specific mucosal IgA. When ARA was prevented from undergoing its downstream metabolic transformation using the 5-lipoxygenase inhibitor zileuton or by blocking its downstream biological signaling through genetic deletion of the Leukotriene B4 receptor 1 (Blt1), the T.mu-mediated enhancement of antigen-specific mucosal IgA production was suppressed. Moreover, both T.mu transfer and dietary supplementation of ARA augmented the efficacy of an oral vaccine against Salmonella infection, with this effect being dependent on Blt1. Our findings elucidate a tripartite circuit linking nutrients from the diet or intestinal microbiota, host lipid metabolism, and the mucosal humoral immune response.


Assuntos
Imunidade nas Mucosas , Imunoglobulina A , Metabolismo dos Lipídeos , Camundongos Endogâmicos C57BL , Receptores do Leucotrieno B4 , Transdução de Sinais , Animais , Metabolismo dos Lipídeos/imunologia , Imunoglobulina A/imunologia , Imunoglobulina A/metabolismo , Transdução de Sinais/imunologia , Camundongos , Receptores do Leucotrieno B4/metabolismo , Receptores do Leucotrieno B4/imunologia , Ácido Araquidônico/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Feminino , Microbioma Gastrointestinal/imunologia , Camundongos Knockout
11.
PLoS One ; 19(5): e0303199, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38723048

RESUMO

This paper presents an optimized preparation process for external ointment using the Definitive Screening Design (DSD) method. The ointment is a Traditional Chinese Medicine (TCM) formula developed by Professor WYH, a renowned TCM practitioner in Jiangsu Province, China, known for its proven clinical efficacy. In this study, a stepwise regression model was employed to analyze the relationship between key process factors (such as mixing speed and time) and rheological parameters. Machine learning techniques, including Monte Carlo simulation, decision tree analysis, and Gaussian process, were used for parameter optimization. Through rigorous experimentation and verification, we have successfully identified the optimal preparation process for WYH ointment. The optimized parameters included drug ratio of 24.5%, mixing time of 8 min, mixing speed of 1175 rpm, petroleum dosage of 79 g, liquid paraffin dosage of 6.7 g. The final ointment formulation was prepared using method B. This research not only contributes to the optimization of the WYH ointment preparation process but also provides valuable insights and practical guidance for designing the preparation processes of other TCM ointments. This advanced DSD method enhances the screening approach for identifying the best preparation process, thereby improving the scientific rigor and quality of TCM ointment preparation processes.


Assuntos
Aprendizado de Máquina , Pomadas , Reologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/administração & dosagem , Medicina Tradicional Chinesa , Composição de Medicamentos/métodos , Dodecilsulfato de Sódio/química , Método de Monte Carlo
12.
Biomacromolecules ; 14(9): 3294-303, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-23937610

RESUMO

Multicomponent poly(ethylene glycol) (PEG) brushes (i.e., ≥ 2 adjacent PEG brushes) can be used to engineer culture substrates with microscale, nonfouling regions decorated with covalently immobilized ligands that mediate biospecific interactions. However, synthesizing such brushes with orthogonal immobilization chemistries to permit differential biofunctionalization is nontrivial and often requires synthesis of PEG-co-polymers. To simplify synthesis and enhance the versatility of such substrates, we developed a protocol for generating orthogonal click-functionalized multicomponent PEG brushes using sequential nucleophilic substitutions by sodium azide, ethanolamine, and propargylamine. The novel application of propargylamine-mediated substitution functionalizes PEG brushes with acetylene groups, and for the first time, ethanolamine-mediated substitution is shown to be sufficient for passivating the "living" polymer chain ends between brush synthesis steps. Thus, our multicomponent PEG brushes present dual orthogonal chemistries (i.e., azido and acetylene groups) for ligand immobilization via versatile copper-free click reactions, which are useful for in situ surface modifications during cell culture.


Assuntos
Polietilenoglicóis/síntese química , Ácidos Polimetacrílicos/síntese química , Adesão Celular , Técnicas de Cultura de Células , Células Cultivadas , Química Click , Células-Tronco Embrionárias/fisiologia , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Cinética , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Propriedades de Superfície
13.
Anal Chim Acta ; 1280: 341850, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37858547

RESUMO

The residues of pesticides and antibiotics have always been a major concern in agriculture and food safety. In order to provide a new method for the rapid detection of organophosphorus pesticides and antibiotics, a novel Cd(II) chain-based zwitterionic metal-organic framework MOF 1 with high sensitivity fluorescence sensing performance was successfully synthesized. A series of researches showed that the water- and pH-stable bifunctional MOF 1 has a great ability to detect phosmet (PSM) and chlortetracycline (CTC) in water through fluorescence quenching effect, with high detection sensitivity, low detection limits (0.0124 µM and 0.0131 µM), short response time (40 s) and reusability. Practical application results revealed that MOF 1 could detect PSM and CTC in milk, beef, chicken and egg samples, with satisfactory recoveries (95.2%-103.7%). As a novel fluorescence probe, MOF 1, is known the first case that can detect PSM in animal-derived samples, and the first dual-function material capable of detecting PSM and CTC. Mechanism studies displayed that competitive absorption and photoinduced electron transfer clearly authenticate the high quenching performance of the material.


Assuntos
Clortetraciclina , Estruturas Metalorgânicas , Praguicidas , Fosmet , Animais , Bovinos , Estruturas Metalorgânicas/química , Cádmio , Água , Compostos Organofosforados , Antibacterianos/análise
14.
Polymers (Basel) ; 14(5)2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35267863

RESUMO

An optimized thermal conductivity model of spherical particle-filled polymer composites considering the influence of interface layer was established based on the classic series and parallel models. ANSYS software was used to simulate the thermal transfer process. Meanwhile, linear low-density polyethylene/alumina (LLDPE/Al2O3) composites with different volume fractions and Al2O3 particle sizes were prepared with the continuous mixer, and the effects of Al2O3 particle size and volume fraction on the thermal conductivity of the composites were discussed. Finally, the test result of the thermal conductivity was analyzed and compared with ANSYS simulations and the model prediction. The results proved that the thermal conductivity model considering the influence of the interface layer could predict the thermal conductivity of LLDPE/Al2O3 composites more precisely.

15.
Biomater Adv ; 141: 213092, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36191539

RESUMO

Functional surfaces that enable both spatial and temporal control of biomolecules immobilization have attracted enormous attention for various fields including smart biointerface materials, high-throughput bioarrays, and fundamental research in the biosciences. Here, a flexible and promising method was presented for regulating the spatiotemporal arrangement of multiple biomolecules by constructing the topographically and chemically diverse polymer brushes patterned surfaces. A series of polymer brushes patterned surfaces, including antifouling brushes patterned surface, epoxy-presenting brushes patterned surface without and with antifouling background layer, were fabricated to control the spatial distribution of protein and cell adhesion through specific and nonspecific means. The fluorescence measurements demonstrated the effectiveness of spatially regulating the density of surface-immobilized protein through controlling the areal thickness of the poly (glycidyl methacrylate) (PGMA) brush patterns, leading to various complex patterns featuring well-defined biomolecule concentration gradients. Furthermore, a multiplexed surface bearing epoxy groups and azido groups with various areal densities was fabricated for regulating the spatiotemporal arrangement of different proteins, enabling binary biomolecules patterns with higher degrees of functionality and complexity. The presented strategy for the spatiotemporal control of biomolecules immobilization would boost the development of dynamic and multifunctional biosystems.


Assuntos
Proteínas Imobilizadas , Polímeros , Adesão Celular , Polímeros/química
16.
Polymers (Basel) ; 13(6)2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33801032

RESUMO

In this work, carbon black (CB)/polyamide 6 (PA6)/polypropylene (PP) microfibrillar composites (MFCs) were fabricated through an extrusion (hot stretching) heat treatment process. The CB-coated conductive PA6 microfibrils with high aspect ratio were in situ generated as a result of the selective accumulation of CB at the interface. At the proper temperature, a 3D entangled conductive structure was constructed in the PP matrix, due to topological entanglement between these conductive microfibrils. This unique conductive structure provided the PP composites with a low electrical conductivity percolation threshold. Moreover, the electromechanical properties of conductive MFCs were investigated for the first time. A great stability, a high sensitivity and a nice reproducibility were achieved simultaneously for CB/PA6/PP MFCs. This work provides a universal and low-cost method for the conductive polymer composites' (CPCs) fabrication as sensing materials.

17.
Polymers (Basel) ; 12(4)2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32290221

RESUMO

During the "slit die extrusion-hot stretching" process, highly oriented polyamide 6 (PA6) dispersed phase was produced and retained in the polypropylene (PP) matrix directly. By adjusting the stretching forces, the PA6 spherical phase evolved into the ellipsoid, rod-like microfibril with a decreasing average diameter; then, the PA6 microfibrils broke. Moreover, the effects of the PA6 phases formed in the process of the microfibrillation on PP's crystallization behaviors were studied systematically. As the stretching forces increased, the crystallization ability and orientation degree of PP crystals improved significantly. Differential scanning calorimetry and polarizing optical microscopy confirmed the formation of PP spherulite, fan-shaped lamellae and a transcrystalline layer under the induction of the PA6 phases with different morphology. In the PP/PA6 microfibrilar composites (MFCs), PP crystals showed smaller average size, more crystals and stronger interface adhesion due to more excellent heterogeneous nucleation ability of the PA6 microfibrils, which made contributions to the improvement of the melt elasticity responses and oxygen barrier properties of the PP/PA6 polymer blends.

18.
Polymers (Basel) ; 12(6)2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32486274

RESUMO

The deformation-induced crystallization of an isotactic polypropylene (iPP) sheet containing a ß-nucleating agent was evaluated. The phase transformation of the ß-modifications was investigated and the crystal morphology was observed at room temperature after stretching at different temperatures. The results showed that the crystallinity increased after solid-state stretching. When the stretching temperature was below the initial crystallization temperature, stretching deformation promoted the orientation of amorphous molecular chains. When the deformation temperature exceeded the crystallization temperature, part of the ß-modifications underwent a phase transformation process and was stretched into a shish-kebab structure. However, once the stretching temperature was close to the melting point, the ß-modifications melted and recrystallized, and the shish-kebab structure underwent stress relaxation due to poor thermal stability, transforming into α-modifications. It was revealed that the crystal phase transformation mechanism of the ß-modifications was based on the orientation of the molecular chains between the adjacent lamellae. In addition, the shish-kebab cylindrite structure played an important role in modifying the tensile and impact properties of the iPP sheet. The tensile and impact strengths increased by as much as 34% and 126%, respectively.

19.
Polymers (Basel) ; 11(4)2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30960603

RESUMO

The microstructure evolution of an isotactic polypropylene (iPP) sheet during solid-state stretching was studied. The transition of the spherulites-cylindrites was evaluated using in-situ two-dimensional wide-angle and small-angle X-ray scattering methods. The crystallinity of stretched iPP sheets was characterized by differential scanning calorimetry. The crystal morphology was observed by means of scanning electron microscopy. It was found that the differences of crystal microstructure of the iPP sheet depended on the stretching strain, which promoted the orientation of molecular chains. Amorphous molecular chains in the spherulites oriented and formed into a mesophase near the yield point, and the partially ordered mesophase was further stretched to form an oriented cylindrite structure after the yield point. The highest relative content of cylindrites appeared at 15% strain. Notably, as the amorphous phase embedded into the lamellae layer, the crystal size decreased with the increase of strain, which indicated that the crystallinity of the stretched iPP sheet was much higher than that of unstretched iPP sheet. The induced cylindrites structure played a more important role in improving the mechanical properties and heat resistance of iPP sheets. Compared with the unstretched iPP sheets, the tensile strength increased by 28%, the notch impact toughness significantly increased by 78%, and the vicat softening point increased from 104 to 112 °C.

20.
Mini Rev Med Chem ; 19(5): 424-436, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30058485

RESUMO

INTRODUCTION: Resveratrol and chalcones are lead compounds with good biological activities. METHOD: In this study, a series of novel derivatives (6-38) between resveratrol and chalcone possessing piperazine moiety have been synthesized, and in vitro anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW-264.7 macrophages and anti-proliferative effect on a panel of human tumor cell lines (Hela, A549 and SGC7901) by MTT assay were evaluated. RESULT: The results demonstrated that the substituents of the NH group of piperazine ring had an obvious influence on biological activities. Especially, compounds 13, 17, 30, 31 and 36 showed good inhibitory effect on the generation of NO compared to dexamethasone. Furthermore, analogs 20, 21, 22 and 25 were found to be the better anti-proliferative effect on 3 human tumor cell lines, which were found to be a better cytotoxic activity to positive control 5-FU. Many compounds displayed low cytotoxic effect on normal cells L02. CONCLUSION: Further FACs analysis showed that compounds 20 and 25 significantly induced apoptosis in A549 cell. These derivatives were considered as the potential anti-inflammatory and anti-tumor agents.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Chalconas/química , Chalconas/farmacologia , Resveratrol/análogos & derivados , Resveratrol/farmacologia , Animais , Anti-Inflamatórios/síntese química , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Chalconas/síntese química , Humanos , Inflamação/tratamento farmacológico , Camundongos , Neoplasias/tratamento farmacológico , Células RAW 264.7 , Resveratrol/síntese química
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