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1.
Macromol Rapid Commun ; 44(20): e2300336, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37571924

RESUMEN

Heterogeneous photocatalysts have attracted extensive attention in photo-induced electron transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization due to their remarkable advantages such as easy preparation, tunable photoelectric properties, and recyclability. In this study, zinc (II) 5,10,15,20-tetrakis(4-aminophenyl)porphyrin (ZnTAPP)-based poly-porphyrin nanoparticles (PTAPP-Zn) are constructed by an emulsion-directed approach. It is investigated as a heterogeneous photocatalyst for PET-RAFT polymerization of various methacrylate monomers under visible light exposure, and the reactions show refined polymerization control with high monomer conversions. Furthermore, it is demonstrated that the PTAPP-Zn nanoparticles with the larger pore size enhance photocatalytic activity in PET-RAFT polymerization. In addition, the capabilities of oxygen tolerance and temporal control are demonstrated and PTAPP-Zn particles can be easily recycled and reused without an obvious decrease in catalytic efficiency.


Asunto(s)
Nanopartículas , Porfirinas , Emulsiones , Polimerizacion , Tomografía de Emisión de Positrones
2.
J Environ Manage ; 334: 117486, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36774898

RESUMEN

Wheat straw is rich in organic matter and nutrients and has the potential to replace peat as the primary raw material in organic nurseries. Using straw as a peat substitute can also aid in reducing the CO2 emissions that result from peat mining. Furthermore, this can avoid resource wastage and eliminate the practice of burning wheat straw, thereby causing pollution. The conventional composting treatment has a long cycle and inability to control substrate properties in a targeted manner. Thus, this study analyzed the physicochemical properties, material science properties, and biological toxicity of straw substrate at the end of fermentation to achieve rapid and targeted regulations of the substrate's overall performance. Wheat straw treated with two types of fermentation (aerobic/anaerobic) and five chemical conditioners (1% CH3COOH, 1% H2SO4, 1% NaOH, 1% K2CO3, and H2O) under different temperature conditions was used. Adjusting the pH of straw substrate to acidic levels (4.47-6.51) reduced the organic matter consumption by 0.27-5.82% under anaerobic digestion than under aerobic composting. Meanwhile, aerobic composting retained more nitrogen (0.12-8.23 mg/g) than anaerobic digestion. The co-fermentation of wheat straw pretreated with 1% H2SO4 resulted in 14.18-46.12% hemicellulose degradation. Co-aerobic straw composting with H2SO4 and K2CO3 at 35 °C reduced the crystallinity of the straw substrate by 6.66 and 7.33%, respectively, as compared to other conditioning agents. CH3COOH lowered the electrical conductivity values of the straw substrate at the end of fermentation (2.33-3.49 mS/cm). Overall, the findings revealed that CH3COOH-cooperative aerobic composting pretreatment at 35 °C is a suitable replacement for the traditional composting process as a method of utilizing straw substrate.


Asunto(s)
Compostaje , Triticum , Triticum/metabolismo , Fermentación , Suelo/química , Nitrógeno/análisis
3.
Macromol Rapid Commun ; 43(11): e2200122, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35394103

RESUMEN

Near-infrared (NIR) light plays an increasingly important role in the field of photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization due to its unique properties. Yet, the NIR photocatalyst with good stability for PET-RAFT polymerization remains promising. Here, a strategy of NIR PET-RAFT polymerization of semifluorinated monomers using fluorophenyl bacteriochlorin as a photocatalyst with strong absorption at the NIR light region (710-780 nm) is reported. In which, the F atoms are used to modify reduced tetraphenylporphyrin structure with enhanced photostability of photocatalyst. Under the irradiation of NIR light (λmax = 740 nm), the PET-RAFT polymerization of semifluorinated methylacrylic monomers presents living/control characteristics and temporal modulation. By the PET-RAFT polymerization-induced self-assembly (PISA) strategy, stable fluorine-containing micelles are constructed in various solvents. In addition, the fluorinated hydrophobic surface is fabricated via a surface-initiated PET-RAFT (SI-PET-RAFT) polymerization using silicon wafer bearing RAFT agents with tunable surface hydrophobicity. This strategy not only enlightens the application of further modified compounds based on porphyrin structure in photopolymerization, but also shows promising potential for the construction of well-defined functional fluoropolymers.


Asunto(s)
Micelas , Polimerizacion
4.
Biomacromolecules ; 20(6): 2338-2349, 2019 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-31017765

RESUMEN

Premature and incomplete drug release is the typical bottleneck of drug release in traditional chemotherapy. Synergistic therapies are highly desirable in medicine and biology because they can compensate for the drawbacks of single therapy and significantly enhance the therapeutic efficacy. Herein, a novel near infrared (NIR)-activated polymeric nanoplatform with upper critical solution temperature (UCST) was constructed for image-guided synergistic photothermal therapy (PTT) and chemotherapy. UCST-responsive amphiphilic block copolymers were synthesized by reversible addition-fragmentation chain-transfer (RAFT) polymerization and then co-assembled with IR780 and cabazitaxel (Cab) to form spherical nanoparticles (NPs). IR780/Cab dual-loaded UCST polymeric NPs can produce local heating upon NIR laser irradiation and further lead to the dissociation of cargo-loaded NPs and controlled release of Cab. IR780 plays the role of both a heating generator and an activator for "on-demand" drug release. The investigation of in vivo fluorescence and photothermal imaging clearly demonstrated tumor targeting. Notably, both in vitro and in vivo studies illustrated that the synergistic PTT and chemotherapy presented better anticancer efficacy than that of PTT and chemotherapy simplely combined. Thus, the well-defined polymeric nanoplatform opens a versatile and effective path to develop image-guided synergistic therapies for tumor treatment.


Asunto(s)
Hipertermia Inducida , Indoles , Rayos Infrarrojos , Neoplasias Mamarias Experimentales/terapia , Nanopartículas , Fototerapia , Animales , Línea Celular Tumoral , Femenino , Indoles/química , Indoles/farmacología , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Endogámicos BALB C , Nanopartículas/química , Nanopartículas/uso terapéutico
5.
Macromol Rapid Commun ; 40(18): e1900240, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31298785

RESUMEN

A pH and thermo dual-responsive supramolecular diblock copolymer is constructed by host-guest recognition of pillar[5]arene and viologen salt. The host polymer, poly(N,N-dimethylaminoethyl methacrylate) bearing pillar[5]arene as the terminal group (P[5]A-PDMAEMA) is synthesized by atom transfer radical polymerization (ATRP). Guest polymer, ethyl viologen-ended poly(N-isopropylacrylamide) (EV-PNIPAM) is prepared by reversible addition-fragmentation chain transfer polymerization. The supramolecular diblock copolymer can be self-assembled into stable supramolecular nanoparticles in aqueous solution at 40 °C, which show excellent pH and thermo responsiveness. The nanoparticles are further applied in the encapsulation of photosensitizers (pyropheophorbide-a, PhA) for photodynamic therapy (PDT). The dual-responsive nanoparticles can efficiently release PhA in acidic environment at 25 °C. Based on the result of cell experiments, PhA-loaded nanomicelles exhibit excellent PDT efficacy and low dark toxicity toward A549 cells. Thus, this supramolecular diblock copolymer enriches the methodology of constructing stimuli-responsive drug carriers and presents a great potential in PDT.


Asunto(s)
Calixarenos/química , Metacrilatos/química , Nanopartículas/química , Nylons/química , Fotoquimioterapia , Fármacos Fotosensibilizantes/administración & dosificación , Células A549 , Acrilamidas/química , Resinas Acrílicas/síntesis química , Resinas Acrílicas/química , Clorofila/administración & dosificación , Clorofila/análogos & derivados , Clorofila/química , Clorofila/uso terapéutico , Portadores de Fármacos , Humanos , Metacrilatos/síntesis química , Micelas , Nylons/síntesis química , Fármacos Fotosensibilizantes/uso terapéutico , Polimerizacion , Polímeros/química
7.
J Cancer ; 15(1): 204-217, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38164282

RESUMEN

Prostate cancer (PCa) is the most common tumor of the male genitourinary system. It will eventually progress to fatal metastatic castration-resistant prostate cancer, for which treatment options are limited. Adipose tissues are distributed in various parts of the body. They have different morphological structures and functional characteristics and are associated with the development of various tumors. Periprostatic adipose tissue (PPAT) is the closest white visceral adipose tissue to the prostate and is part of the PCa tumor microenvironment. Studies have shown that PPAT is involved in PCa development, progression, invasion, and metastasis through the secretion of multiple active molecules. Factors such as obesity, diet, exercise, and organochlorine pesticides can affect the development of PCa indirectly or directly through PPAT. Based on the mechanism of PPAT's involvement in regulating PCa, this review summarized various diagnostic and therapeutic approaches for PCa with potential applications to assess the progression of patients' disease and improve clinical outcomes.

8.
PLoS One ; 19(7): e0306860, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38980876

RESUMEN

BACKGROUND: Benign prostatic hyperplasia (BPH) is a common health disorder of the male genitourinary system with a high prevalence, especially among middle-aged and older adults, which seriously affects men's quality of life. Inflammatory markers derived from complete blood cell count (CBC) have previously been considered a prognostic indicator for various diseases, but little is known about their relationship with BPH. This study evaluated the relationship between complete blood cell count (CBC)-derived inflammatory biomarkers and BPH. METHODS: Data for this cross-sectional study were gathered from the National Health and Nutrition Examination Survey (NHANES) between 2001 and 2008. Using multiple logistic regressions, the study examined the association between benign prostatic hyperplasia(BPH) and Inflammatory biomarkers derived from blood cell counts such as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), Systemic Inflammatory Response Index (SIRI) and Systemic Immunoinflammatory Index (SII). RESULTS: 3,919 participants were included, with a median age of 61.00 (52.00-71.00) years old. Among them, 609 participants had benign prostatic hyperplasia, with a prevalence of 15.54%. Upon accounting for confounding factors, the study revealed a positive correlation between the plurality of BPH PLR and SII. However, MLR, NLR, and SIRI did not significantly correlate with the prevalence of BPH (p>0.05). In contrast to the lowest quartile, higher quartiles of PLR (OR = 1.93[1.38-2.69]) and SII (OR = 1.71[1.22-2.40]) were linked to an elevated risk of BPH. Interaction tests showed that age, body mass index, hypertension, diabetes, smoking, and drinking had no significant effect on this positive correlation (p for interaction>0.05). In addition, we found a roughly linear association between SII, PLR, and BPH using smoothed curve fitting. CONCLUSIONS: According to our research, high levels of PLR and SII are positively linked with an increased risk of BPH in middle-aged and elderly individuals in the United States. The results compensate for previous studies that still need to be validated with larger prospective cohorts.


Asunto(s)
Biomarcadores , Encuestas Nutricionales , Hiperplasia Prostática , Humanos , Masculino , Hiperplasia Prostática/sangre , Hiperplasia Prostática/epidemiología , Persona de Mediana Edad , Anciano , Biomarcadores/sangre , Estados Unidos/epidemiología , Estudios Transversales , Recuento de Células Sanguíneas , Inflamación/sangre , Monocitos/metabolismo , Linfocitos , Neutrófilos , Prevalencia
9.
Water Res ; 254: 121405, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38447376

RESUMEN

The accumulation and transformation of lead (Pb) and arsenic (As) during the digestion of sewage sludge (SS) by black soldier fly larvae (BSFL) remain unclear. In this study, we used 16 s rRNA and metagenomic sequencing techniques to investigate the correlation between the microbial community, metalloregulatory proteins (MRPs), and Pb and As migration and transformation. During the 15-day test period, BSFL were able to absorb 34-48 % of Pb and 32-45 % of As into their body. Changes in bacterial community abundance, upregulation of MRPs, and redundancy analysis (RDA) results confirmed that ZntA, EfeO, CadC, ArsR, ArsB, ArsD, and ArsA play major roles in the adsorption and stabilization of Pb and As, which is mainly due to the high contribution rates of Lactobacillus (48-59 %) and Enterococcus (21-23 %). Owing to the redox reaction, the regulation of the MRPs, and the change in pH, the Pb and As in the BSFL residue were mainly the residual fraction (F4). The RDA results showed that Lactobacillus and L.koreensis could significantly (P < 0.01) reduce the reducible fraction (F2) and F4 of Pb, whereas Firmicutes and L.fermentum can significantly (P < 0.05) promote the transformation of As to F4, thus realizing the passivation Pb and As. This study contributes to the understanding of Pb and As in SS adsorbed by BSFL and provides important insights into the factors that arise during the BSFL-mediated migration of Pb and As.


Asunto(s)
Arsénico , Dípteros , Eliminación de Residuos , Animales , Larva/metabolismo , Aguas del Alcantarillado , Alimento Perdido y Desperdiciado , Plomo/metabolismo , Alimentos , Biotransformación , Bacterias , Lactobacillus
10.
Bioresour Technol ; 406: 131031, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38925402

RESUMEN

The sustainable management of agricultural waste is essential for curtailing environmental contamination. To address the shortcomings of single treatment methods, this study evaluated the feasibility of combining membrane-covered composting (MC) with vermicomposting. Based on this, the integrated effects of different biochar addition strategies on the combined process were investigated. The aim was to improve the efficiency of vermicomposting while eliminating the negative effects of biochar on earthworms. Addition of biochar before membrane-covered composting increased total earthworm biomass by 25.6 - 31.4 % and reproduction rate by 13.4 - 23.9 %. Specifically, the electrical conductivity (EC) (1061.0 - 1112.0 uS/cm) of the vermicompost was significantly reduced, while the total nutrient content (42.3 - 42.6 mg/g) and germination index (GI) (103.9 - 108.4 %) were maximized. Additionally, reductions in the carbon-to-nitrogen ratio and volatile content were observed. Overall, combination process is a promising approach to improve the quality of vermicomposting. The study's results offer a novel perspective on the value-added treatment of agricultural waste.


Asunto(s)
Carbón Orgánico , Compostaje , Lignina , Oligoquetos , Suelo , Oligoquetos/metabolismo , Animales , Carbón Orgánico/farmacología , Carbón Orgánico/química , Compostaje/métodos , Suelo/química , Biomasa , Nitrógeno , Conductividad Eléctrica , Biodegradación Ambiental , Carbono
11.
Waste Manag ; 176: 64-73, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38266476

RESUMEN

During the conversion of pig manure by black soldier fly larvae (BSFL), the accumulation and speciation changes of heavy metals (HMs) have adverse effects on the environment. In this study, corn straw, rice straw, bamboo chips (BC), wood chips, and rice husk char were added to a bioconversion system to study the accumulation, migration, speciation changes, and microbial correlations of HMs. The results indicated that the addition of BC was most beneficial for the accumulation of HMs (47-72 %) in the BSFL body. In the BC group, the accumulation effect of the BSFL body on zinc (Zn) and arsenic (As) was the most evident (72 and 71 %, respectively). The results of linear fitting (R2 > 0.90) and redundancy analysis (RDA; 90 %) indicated that the bacterium Bacillaceae (Bacillus) was beneficial for increasing the larval weight (LW) of BSFL, and a higher LW accumulated HMs. The addition of BC helped reduce the total amount (6-51 %) of available states (weak acid extraction and reducible states) in the BSFL residue. The RDA results indicated that bacteria (55-92 %) affected the transformation of HM speciation. For example, Zn and cadmium were mainly affected by Firmicutes, whereas copper and chromium were affected by Bacteroidetes. Proteobacteria and Pseudomonas formosensis affected the conversion of lead and As. This study provides important insights into the adsorption of HMs from pig manure by BSFL.


Asunto(s)
Arsénico , Dípteros , Metales Pesados , Animales , Porcinos , Larva , Estiércol , Disponibilidad Biológica , Bacterias
12.
Front Endocrinol (Lausanne) ; 15: 1348310, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38904040

RESUMEN

Objectives: The relationship between cathepsins and prostate cancer (PCa) has been reported. However, there is a lack of research on cathepsins and benign prostate diseases (BPDs). This study investigated the potential genetic link between cathepsins and BPDs through the utilization of Mendelian randomization (MR) analysis to determine if a causal relationship exists. Methods: Publicly accessible summary statistics on BPDs were obtained from FinnGen Biobank. The data comprised 149,363 individuals, with 30,066 cases and 119,297 controls for BPH, and 123,057 individuals, with 3,760 cases and 119,297 controls for prostatitis. The IEU OpenGWAS provided the Genome-wide association data on ten cathepsins. To evaluate the causal relationship between BPDs and cathepsins, five distinct MR analyses were employed, with the primary method being the inverse variance weighted (IVW) approach. Additionally, sensitivity analyses were conducted to examine the horizontal pleiotropy and heterogeneity of the findings. Results: The examination of IVW MR findings showed that cathepsin O had a beneficial effect on BPH (IVW OR=0.94, 95% CI 0.89-0.98, P=0.0055), while cathepsin X posed a threat to prostatitis (IVW OR=1.08, 95% CI 1.00-1.16, P=0.047). Through reverse MR analysis, it was revealed that prostatitis had an adverse impact on cathepsin V (IVW OR=0.89, 95% CI 0.80-0.99, P=0.035), while no favorable association was observed between BPH and cathepsins. The results obtained from MR-Egger, weighted median, simple mode, and weighted mode methods were consistent with the findings of the IVW approach. Based on sensitivity analyses, heterogeneity, and horizontal pleiotropy are unlikely to distort the results. Conclusion: This study offers the initial evidence of a genetic causal link between cathepsins and BPDs. Our findings revealed that cathepsin O was beneficial in preventing BPH, whereas cathepsin X posed a potential threat to prostatitis. Additionally, prostatitis negatively affected cathepsin V level. These three cathepsins could be targets of diagnosis and treatment for BPDs, which need further research.


Asunto(s)
Catepsinas , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Hiperplasia Prostática , Humanos , Masculino , Catepsinas/genética , Hiperplasia Prostática/genética , Hiperplasia Prostática/epidemiología , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/epidemiología , Prostatitis/genética , Prostatitis/epidemiología , Enfermedades de la Próstata/genética , Enfermedades de la Próstata/epidemiología
13.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 30(2): 403-8, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23858770

RESUMEN

This paper is aimed to fulfill a prototype system used to classify and retrieve retinal image automatically. With the content-based image retrieval (CBIR) technology, a method to represent the retinal characteristics mixing the fundus image color (gray) histogram with bright, dark region features and other local comprehensive information was proposed. The method uses kernel principal component analysis (KPCA) to further extract nonlinear features and dimensionality reduced. It also puts forward a measurement method using support vector machine (SVM) on KPCA weighted distance in similarity measure aspect. Testing 300 samples with this prototype system randomly, we obtained the total image number of wrong retrieved 32, and the retrieval rate 89.33%. It showed that the identification rate of the system for retinal image was high.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Almacenamiento y Recuperación de la Información/métodos , Oftalmoscopía/normas , Reconocimiento de Normas Patrones Automatizadas/métodos , Retina/patología , Algoritmos , Fondo de Ojo , Humanos , Análisis Numérico Asistido por Computador , Vasos Retinianos/patología
14.
J Am Chem Soc ; 134(10): 4782-9, 2012 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-22353186

RESUMEN

The large research effort focused on enhancing nonviral transfection vectors has clearly demonstrated that their macromolecular structure has a significant effect on their transfection efficacy. The 3D branched polymeric structures, such as dendrimers, have proved to be a very effective structure for polymeric transfection vectors; however, so far the dendritic polymers have not delivered on their promise. This is largely because a wide range of dendritic polymer materials with tailored multifunctional properties and biocompatibility required for such applications are not yet accessible by current routes. Herein, we report the design and synthesis of new 3D "Single Cyclized" polymeric gene vectors with well-defined compositions and functionalities via a one-step synthesis from readily available vinyl monomers. We observe that this polymer structure of a single chain linked to itself interacts differently with plasmid DNA compared to conventional vectors and when tested over a range of cell types, has a superior transfection profile in terms of both luciferase transfection capability and preservation of cell viability. This new knotted structure shows high potential for gene delivery applications through a combination of simplicity in synthesis, scalability, and high performance.


Asunto(s)
Técnicas de Transferencia de Gen , Polímeros/química , Materiales Biocompatibles , Ciclización , Vectores Genéticos , Microscopía Fluorescente
15.
J Mater Sci Mater Med ; 23(1): 25-35, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22143908

RESUMEN

Thermoresponsive polymers have been widely used for in situ formed hydrogels in drug delivery and tissue engineering as they are easy to handle and their shape can easily conform to tissue defects. However, non-covalent bonding and mechanical weakness of these hydrogels limit their applications. In this study, a physically and chemically in situ cross-linkable hydrogel system was developed from a novel thermoresponsive hyperbranched PEG based copolymer with multi acrylate functionality, which was synthesized via an 'one pot and one step' in situ deactivation enhanced atom transfer radical co-polymerization of poly(ethylene glycol) diacrylate (PEGDA, M(n) = 258 g mol(-1)), poly(ethylene glycol) methyl ether methacrylate (PEGMEMA, M(n )= 475 g mol(-1)) and (2-methoxyethoxy) ethyl methacrylate (MEO(2)MA). This hyperbranched copolymer was tailored to have the lower critical solution temperature to form physical gelation around 37°C. Meanwhile, with high level of acrylate functionalities, a chemically cross-linked gel was formed from this copolymer using thiol functional cross-linker of pentaerythritol tetrakis (3-mercaptopropionate) (QT) via thiol-ene Michael addition reaction. Furthermore, a semi-interpenetrated polymer networks (semi-IPN) structure was developed by combining this polymer with hyaluronic acid (HA), leading to an in situ cross-linkable hydrogel with significantly increased porosity, enhanced swelling behavior and improved cell adhesion and viability both in 2D and 3D cell culture models.


Asunto(s)
Ácido Hialurónico/química , Hidrogeles , Polímeros/química , Animales , Células Cultivadas , Reactivos de Enlaces Cruzados/química , Calor , Conejos
16.
Chem Commun (Camb) ; 58(18): 2991-2994, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35147152

RESUMEN

A pH-triggering supramolecular antibacterial photosensitizer was constructed by host-guest interaction between a water-soluble porphyrin photosensitizer and carboxylatopillar[5]arene (P[5]). The formation of the supramolecular complex not only improves the biocompatibility of the photosensitizer, but also enhances antibacterial efficacy by pH-triggering dissociation under the low pH bacterial microenvironment.


Asunto(s)
Antibacterianos/farmacología , Hidrocarburos Aromáticos/farmacología , Fármacos Fotosensibilizantes/farmacología , Antibacterianos/química , Escherichia coli/efectos de los fármacos , Hidrocarburos Aromáticos/química , Pruebas de Sensibilidad Microbiana , Fármacos Fotosensibilizantes/química , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Staphylococcus aureus/efectos de los fármacos
17.
Trends Biotechnol ; 40(12): 1503-1518, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36270903

RESUMEN

Modern agriculture has evolved technological innovations to sustain crop productivity. Recent advances in biorefinery technology use crop residue as feedstock, but this raises carbon sequestration concerns as biorefining utilizes carbon that would otherwise be returned to the soil, thus causing a decline in crop productivity. Furthermore, biorefining generates abundant lignin waste that significantly impedes the efficiency of biorefineries. Valorizing lignin into advanced nanobiotechnologies for agriculture provides a unique opportunity to balance bioeconomy and soil carbon sequestration. Integration of agricultural practices such as utilization of agrochemicals, fertilizers, soil modifiers, and mulching with lignin nanobiotechnologies promotes crop productivity and also enables advanced manufacturing of high-value bioproducts from lignin. Lignin nanobiotechnologies thus represent state-of-the-art innovations to transform both the bioeconomy and sustainable agriculture.


Asunto(s)
Agricultura , Lignina , Secuestro de Carbono , Suelo/química , Carbono , Fertilizantes
18.
Adv Healthc Mater ; 11(4): e2102015, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34787954

RESUMEN

The treatment of pathogenic bacterial infection has long been the most serious threat to human life and attracted widespread attention. Herein, a supramolecular photosensitizer platform based on carboxylatopillar[5]arene (CP5) and tetrafluorophenyl porphyrin functionalized with a quaternary ammonium group (TFPP-QA) for combating bacteria and dispersing biofilm via photodynamic treatment is constructed. By introducing the host macrocycle CP5 and host-guest interaction, the supramolecular photosensitizer has great biocompatibility and acid responsiveness. On the one hand, the acid-triggered dissociation of TFPP-QA/CP5 could induce the porphyrin photosensitizer to target bacterial cells and disrupt the charge balance of bacterial membranes, enhance the permeability of the bacterial membrane. On the other hand, the TFPP-QA/CP5 antibacterial platform possesses superb reactive oxygen species (ROS) generation capability under light irradiation, leading to enhanced photodynamic antibacterial efficacy. The in vitro and in vivo studies show that the supramolecular photosensitizers exhibit high antibacterial efficiency and biofilm dissipation effect under 660 nm light irradiation. Therefore, it is anticipated that the rational design and integration of photosensitizers and quaternary ammonium compounds through the supramolecular strategy would provide a promising prospect for clinical photodynamic antimicrobial therapy.


Asunto(s)
Infecciones Bacterianas , Fotoquimioterapia , Porfirinas , Infecciones Bacterianas/tratamiento farmacológico , Biopelículas , Calixarenos , Humanos , Fármacos Fotosensibilizantes/farmacología , Porfirinas/farmacología , Compuestos de Amonio Cuaternario
19.
J Am Chem Soc ; 133(33): 13130-7, 2011 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-21744868

RESUMEN

Controlled/living radical polymerization (CRP) is a widely used technique that allows the synthesis of defined polymer architectures through precise control of molecular weights and distributions. However, the architectures of polymers prepared by the CRP techniques are limited to linear, cross-linked, and branched/dendritic structures. Here, we report the preparation of a new 3D single cyclized polymer chain structure from an in situ deactivation enhanced atom transfer radical polymerization of multivinyl monomers (MVMs), which are conventionally used for the production of branched/cross-linked polymeric materials as defined by P. Flory and W. Stockmayer nearly 70 years ago. We provide new evidence to demonstrate that it is possible to kinetically control both the macromolecular architecture and the critical gelling point in the polymerization of MVMs, suggesting the classical Flory-Stockmayer mean field theory should be supplemented with a new kinetic theory based on the space and instantaneous growth boundary concept.


Asunto(s)
Polimerizacion , Polímeros/química , Polivinilos/química , Ciclización , Cinética , Estructura Molecular , Temperatura de Transición
20.
Nanotechnology ; 22(6): 065604, 2011 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-21212483

RESUMEN

The synthesis of a new PEG based hyperbranched copolymer of poly(ethylene glycol) methyl ether methacrylate-co-ethylene glycol dimethacrylate (PEGMEMA-co-EGDMA) was achieved via a one-step in situ deactivation enhanced atom transfer radical polymerization (DE-ATRP). Then, hollow PEG based nanospheres were fabricated from this polymer using a solvent evaporation method and post-stabilisation strategy. Furthermore, the analysis using a cellular metabolic activity assay proved that the copolymer did not affect cellular metabolism, indicating that this PEG based polymeric nanosphere has potential for use in drug delivery applications.


Asunto(s)
Nanosferas/química , Polietilenglicoles/química , Ácidos Polimetacrílicos/química , Células 3T3 , Animales , Supervivencia Celular/efectos de los fármacos , Ratones , Microscopía Electrónica de Rastreo , Resonancia Magnética Nuclear Biomolecular , Polietilenglicoles/farmacología , Polimerizacion
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