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1.
Plant Cell ; 36(7): 2652-2667, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38573521

RESUMO

Temperature shapes the geographical distribution and behavior of plants. Understanding the regulatory mechanisms underlying the plant heat stress response is important for developing climate-resilient crops, including maize (Zea mays). To identify transcription factors (TFs) that may contribute to the maize heat stress response, we generated a dataset of short- and long-term transcriptome changes following a heat treatment time course in the inbred line B73. Co-expression network analysis highlighted several TFs, including the class B2a heat shock factor (HSF) ZmHSF20. Zmhsf20 mutant seedlings exhibited enhanced tolerance to heat stress. Furthermore, DNA affinity purification sequencing and Cleavage Under Targets and Tagmentation assays demonstrated that ZmHSF20 binds to the promoters of Cellulose synthase A2 (ZmCesA2) and three class A Hsf genes, including ZmHsf4, repressing their transcription. We showed that ZmCesA2 and ZmHSF4 promote the heat stress response, with ZmHSF4 directly activating ZmCesA2 transcription. In agreement with the transcriptome analysis, ZmHSF20 inhibited cellulose accumulation and repressed the expression of cell wall-related genes. Importantly, the Zmhsf20 Zmhsf4 double mutant exhibited decreased thermotolerance, placing ZmHsf4 downstream of ZmHsf20. We proposed an expanded model of the heat stress response in maize, whereby ZmHSF20 lowers seedling heat tolerance by repressing ZmHsf4 and ZmCesA2, thus balancing seedling growth and defense.


Assuntos
Regulação da Expressão Gênica de Plantas , Glucosiltransferases , Fatores de Transcrição de Choque Térmico , Resposta ao Choque Térmico , Proteínas de Plantas , Zea mays , Zea mays/genética , Zea mays/fisiologia , Zea mays/metabolismo , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Resposta ao Choque Térmico/genética , Fatores de Transcrição de Choque Térmico/genética , Fatores de Transcrição de Choque Térmico/metabolismo , Termotolerância/genética , Celulose/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
2.
Anal Chem ; 96(24): 9780-9789, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38848497

RESUMO

Dental caries is one of the most common diseases affecting more than 2 billion people's health worldwide. In a clinical setting, it is challenging to predict and proactively guard against dental cavities prior to receiving a confirmed diagnosis. Streptococcus mutans (S. mutans) in saliva has been recognized as the main causative bacterial agent that causes dental caries. High sensitivity, good selectivity, and a wide detection range are incredibly important factors to affect S. mutans detection in practical applications. In this study, we present a portable saliva biosensor designed for the early detection of S. mutans with the potential to predict the occurrence of dental cavities. The biosensor was fabricated using a S. mutans-specific DNA aptamer and S. mutans-imprinted polymers. Methylene blue was utilized as a redox probe in the sensor to generate current signals for analysis. When S. mutans enters complementarily S. mutans cavities, it blocks electron transfer between methylene blue and the electrode, resulting in decreases in the reduction current signal. The signal variations are associated with S. mutans concentrations that are useful for quantitative analysis. The linear detection range of S. mutans is 102-109 cfu mL-1, which covers the critical concentration of high caries risk. The biosensor exhibited excellent selectivity toward S. mutans in the presence of other common oral bacteria. The biosensor's wide detection range, excellent selectivity, and low limit of detection (2.6 cfu mL-1) are attributed to the synergistic effect of aptamer and S. mutans-imprinted polymers. The sensor demonstrates the potential to prevent dental caries.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Cárie Dentária , Saliva , Streptococcus mutans , Saliva/microbiologia , Saliva/química , Streptococcus mutans/isolamento & purificação , Técnicas Biossensoriais/instrumentação , Cárie Dentária/diagnóstico , Cárie Dentária/microbiologia , Aptâmeros de Nucleotídeos/química , Humanos , Azul de Metileno/química , Técnicas Eletroquímicas/instrumentação
3.
BMC Plant Biol ; 24(1): 453, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789944

RESUMO

BACKGROUND: Impatiens is an important genus with rich species of garden plants, and its distribution is extremely extensive, which is reflected in its diverse ecological environment. However, the specific mechanisms of Impatiens' adaptation to various environments and the mechanism related to lignin remain unclear. RESULTS: Three representative Impatiens species,Impatiens chlorosepala (wet, low degree of lignification), Impatiens uliginosa (aquatic, moderate degree of lignification) and Impatiens rubrostriata (terrestrial, high degree of lignification), were selected and analyzed for their anatomical structures, lignin content and composition, and lignin-related gene expression. There are significant differences in anatomical parameters among the stems of three Impatiens species, and the anatomical structure is consistent with the determination results of lignin content. Furthermore, the thickness of the xylem and cell walls, as well as the ratio of cell wall thickness to stem diameter have a strong correlation with lignin content. The anatomical structure and degree of lignification in Impatiens can be attributed to the plant's growth environment, morphology, and growth rate. Our analysis of lignin-related genes revealed a negative correlation between the MYB4 gene and lignin content. The MYB4 gene may control the lignin synthesis in Impatiens by controlling the structural genes involved in the lignin synthesis pathway, such as HCT, C3H, and COMT. Nonetheless, the regulation pathway differs between species of Impatiens. CONCLUSIONS: This study demonstrated consistency between the stem anatomy of Impatiens and the results obtained from lignin content and composition analyses. It is speculated that MYB4 negatively regulates the lignin synthesis in the stems of three Impatiens species by regulating the expression of structural genes, and its regulation mechanism appears to vary across different Impatiens species. This study analyses the variations among different Impatiens plants in diverse habitats, and can guide further molecular investigations of lignin biosynthesis in Impatiens.


Assuntos
Impatiens , Lignina , Caules de Planta , Lignina/metabolismo , Caules de Planta/genética , Caules de Planta/anatomia & histologia , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Impatiens/genética , Impatiens/metabolismo , Impatiens/crescimento & desenvolvimento , Ecossistema , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Adaptação Fisiológica/genética , Regulação da Expressão Gênica de Plantas , Especificidade da Espécie , Genes de Plantas , Parede Celular/metabolismo , Parede Celular/genética
4.
Environ Sci Technol ; 57(7): 2804-2812, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36749610

RESUMO

Nanoplastics (NPs, <1 µm) are of great concern worldwide because of their high potential risk toward organisms in aquatic systems, while very little work has been focused on their tissue-specific toxicokinetics due to the limitations of NP quantification for such a purpose. In this study, NPs with two different sizes (86 and 185 nm) were doped with palladium (Pd) to accurately determine the uptake and depuration kinetics in various tissues (intestine, stomach, liver, gill, and muscle) of tilapia (Oreochromis niloticus) in water, and subsequently, the corresponding toxic effects in the intestine were explored. Our results revealed uptake and depuration constants of 2.70-378 L kg-1 day-1 and 0.138-0.407 day-1 for NPs in tilapia for the first time, and the NPs in tissues were found to be highly dependent on the particle size. The intestine exhibited the greatest relative accumulation of both sizes of NPs; the smaller NPs caused more severe damage than the larger NPs to the intestinal mucosal layer, while the larger NPs induced a greater impact on microbiota composition. The findings of this work explicitly indicate the size-dependent toxicokinetics and intestinal toxicity pathways of NPs, providing new insights into the ecological effects of NPs on aquatic organisms.


Assuntos
Ciclídeos , Tilápia , Poluentes Químicos da Água , Animais , Tilápia/metabolismo , Ciclídeos/metabolismo , Microplásticos , Intestinos , Fígado/metabolismo , Poluentes Químicos da Água/metabolismo
5.
Molecules ; 27(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36296500

RESUMO

Osthol (osthole), known as a neuroprotective drug, has shown potent anticancer activity. However, the potential clinical application of osthol is limited due to its low water solubility and low bioavailability. Polybutyl cyanoacrylate (PBCA) has been widely used to improve the solubility of drugs with poor water solubility. In this study, an orthogonal experimental design (OED) was applied to design the preparation process of PBCA nanoparticles (NPs). Then, nanoparticles were prepared and evaluated in terms of physicochemical properties, in vitro release, and cellular uptake, etc. Further, the anti-cancer activity of osthol-PBCA NPs was demonstrated in SH-SY5Y cells. The pharmacokinetics and area under the curve (AUC) were investigated. The obtained osthol-NPs presented a spherical shape with a particle size of 110 ± 6.7 nm, a polydispersity index (PDI) of 0.126, and a zeta potential of −13 ± 0.32 mV. Compared with the free osthol, the drugs in osthol-NPs presented better stability and sustained release pattern activity. In vitro analysis using SH-SY5Y neuroblastoma cells showed that osthol-loaded nanoparticles displayed a significantly enhanced intracellular absorption process (three times) and cytotoxicity compared with free osthol (p < 0.05, increased 10−20%). The in vivo pharmacokinetic study revealed that the AUC of osthol-NPs was 3.3-fold higher than that of free osthol. In conclusion, osthol-PBCA NPs can enhance the bioactivity of osthol, being proposed as a novel, promising vehicle for drug delivery.


Assuntos
Embucrilato , Nanopartículas , Neuroblastoma , Fármacos Neuroprotetores , Humanos , Embucrilato/química , Portadores de Fármacos/química , Preparações de Ação Retardada , Neuroblastoma/tratamento farmacológico , Nanopartículas/química , Tamanho da Partícula , Água
6.
Anal Chem ; 93(17): 6698-6705, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33871972

RESUMO

There is a growing concern about the effects of nanoplastics on biological safety and human health because of their global ubiquity in the environment. Methodologies for quantitative analysis of nanoplastics are important for the critical evaluation of their possible risks. Herein, a sensitive yet simple and environmentally friendly extraction approach mediated by protein corona is developed and coupled to pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) for nanoplastic determination in environmental waters. The developed methodology involved the formation of protein corona by addition of bovine serum albumin (BSA) to samples and protein precipitation via salting out. Then, the resulting extract was directly introduced to Py-GC/MS for nanoplastic mass quantification. Taking 50 nm polystyrene (PS) particles as a model, the highest extraction efficiency for nanoplastics was achieved under the extraction conditions of BSA concentration of 20 mg/L, equilibration time of 5 min, pH 3.0, 10% (w/v) NaCl, incubation temperature of 80 °C, and incubation period of 15 min. The extraction was confirmed to be mediated by the protein corona by transmission electron microscopy (TEM) analysis of the extracted nanoplastics. In total, 1.92 and 2.82 µg/L PS nanoplastics were detected in river water and the influent of wastewater treatment plant (WWTP), respectively. Furthermore, the feasibility of the present methodology was demonstrated by applying to extract PS and poly(methyl methacrylate) (PMMA) nanoplastics from real waters with recoveries of 72.1-98.9% at 14.2-50.4 µg/L spiked levels. Consequently, our method has provided new insights and possibilities for the investigation of nanoplastic pollution and its risk assessment in the environment.


Assuntos
Coroa de Proteína , Poluentes Químicos da Água , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Microplásticos , Poliestirenos/análise , Pirólise , Poluentes Químicos da Água/análise
7.
Environ Sci Technol ; 55(5): 3032-3040, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33600167

RESUMO

Micro- and nanoplastics unavoidably enter into organisms and humans as a result of widespread exposures through drinking waters, foods, and even inhalation. However, owing to the limited availability of quantitative analytical methods, the effect of nanoplastics inside animal bodies is poorly understood. Herein, we report a sensitive and robust method to determine the chemical composition, mass concentration, and size distribution of nanoplastics in biological matrices. This breakthrough is based on a novel procedure including alkaline digestion and protein precipitation to extract nanoplastics from tissues of aquatic animals, followed by quantitative analysis with pyrolysis gas chromatography-mass spectrometry. The optimized procedure exhibited good reproducibility and high sensitivity with the respective detection limits of 0.03 µg/g for polystyrene (PS) nanoplastics and 0.09 µg/g poly(methyl methacrylate) (PMMA) nanoplastics. This method also preserved the original morphology and size of nanoplastics. Furthermore, to demonstrate the feasibility of the proposed method, 14 species of aquatic animals were collected, and PS nanoplastics in a concentration range of 0.093-0.785 µg/g were detected in three of these animals. Recovery rates of 73.0-89.1% were further obtained for PS and PMMA nanospheres when they were spiked into the tissues of Zebra snail and Corbicula fluminea at levels of 1.84-2.12 µg/g. Consequently, this method provides a powerful tool for tracking nanoplastics in animals.


Assuntos
Poliestirenos , Poluentes Químicos da Água , Animais , Microplásticos , Polimetil Metacrilato , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise
8.
Molecules ; 25(12)2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32560428

RESUMO

With the rapid development of portable and wearable electronic devices, self-supporting flexible supercapacitors have attracted much attention, and higher requirements have been put forward for the electrode of the device, that is, it is necessary to have good mechanical properties while satisfying excellent electrochemical performance. In this work, a facile method was invented to obtain excellent self-supported flexible electrode materials with high mechanical properties and outstanding electrochemical performance by combining cellulose nanofibrils (CNFs) and reduced graphene oxide (RGO). We focused on the effect of the ratio of the addition of CNFs and the formation process of the film on the electrochemical and mechanical properties. The results show that the CNFs/RGO12 (where the ratio of CNFs to GO is 1:2) film displayed outstanding comprehensive properties; its tensile strength and conductivity were up to 83 MPa and 202.94 S/m, respectively, and its CA value was as high as 146 mF cm-2 under the current density of 5 mA cm-2. Furthermore, the initial retention rate of the specific capacitance was about 83.7% when recycled 2000 times; moreover, its capacitance did not change much after perpendicular bending 200 times. Therefore, the films prepared by this study have great potential in the field of flexible supercapacitors.


Assuntos
Celulose/química , Capacitância Elétrica , Condutividade Elétrica , Grafite/química , Membranas Artificiais , Nanofibras/química
9.
Beijing Da Xue Xue Bao Yi Xue Ban ; 47(1): 98-103, 2015 Feb 18.
Artigo em Zh | MEDLINE | ID: mdl-25686337

RESUMO

OBJECTIVE: To evaluate facial soft tissue 3-deminsion changes of skeletal Class III malocclusion patients after orthognathic surgery using structure light scanning technique. METHODS: Eight patients [3 males and 5 females, aged (27.08 ± 4.42) years] with Class III dentoskeletal relationship who underwent a bimaxillary orthognathic surgical procedure involving advancement of the maxilla by Le Fort I osteotomy and mandibular setback by bilateral sagittal split ramus osteotomy (BSSO) and genioplasty to correct deformity were included. 3D facial images were obtained by structure light scanner for all the patients 2 weeks preoperatively and 6 months postoperatively. The facial soft tissue changes were evaluated in 3-dimension. The linear distances and angulation changes for facial soft tissue landmarks were analyzed. The soft tissue volumetric changes were assessed too. RESULTS: There were significant differences in the sagittal and vertical changes of soft tissue landmarks. The greatest amount of soft tissue change was close to lips. There were more volumetric changes in the chin than in the maxilla, and fewer in the forehead. CONCLUSION: After biomaxillary surgery, there were significant facial soft tissue differences mainly in the sagittal and vertical dimension for skeletal Class III patients. The structure light 3D scanning technique can be accurately used to estimate the soft tissue changes in patients who undergo orthognathic surgery.


Assuntos
Cefalometria , Face/anatomia & histologia , Imageamento Tridimensional , Cirurgia Ortognática , Adulto , Queixo , Ossos Faciais , Feminino , Humanos , Lábio , Masculino , Má Oclusão Classe III de Angle , Mandíbula , Maxila , Procedimentos Cirúrgicos Ortognáticos , Osteotomia Sagital do Ramo Mandibular , Dimensão Vertical , Adulto Jovem
10.
Anal Chem ; 86(10): 4739-47, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24745793

RESUMO

Online coupling of in-tube solid phase microextraction (IT-SPME) with direct analysis in real time mass spectrometry (DART-MS) was realized for the first time and applied in the analysis of triazine herbicides in lake water and orange juice. We incorporated single-wall carbon nanotubes (SWNTs) into a polymer monolith containing methacrylic acid (MAA) and ethylene dimethacrylate (EDMA) to form a novel poly(methacrylic acid-co-ethylene dimethacrylate-co-single wall carbon nanotubes) (poly(MAA-EDMA-SWNT)) monolith, which was then used in IT-SPME for enrichment of six triazine herbicides from water samples. With the online combination of IT-SPME with DART-MS, the analytes desorbed from the monolith were directly ionized by DART and transferred into MS for detection, thus rapid determination was achieved. Compared with regular DART-MS method, this online IT-SPME-DART-MS method was more sensitive and reproducible, because of the IT-SPME procedures and the isotope-labeled internal standard used in the experiment. Six triazine herbicides were determined simultaneously using this method with good linearity (R(2) > 0.998). The limit of quantification (signal-to-noise ratio of S/N = 10) of the six herbicides were only 0.06-0.46 ng/mL. The proposed method has been applied to determine triazine herbicides in lake water and orange juice, showing satisfactory recovery (85%-106%) and reproducibility (relative standard deviation of RSD = 3.1%-10.9%).


Assuntos
Herbicidas/análise , Resíduos de Praguicidas/análise , Triazinas/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Espectrometria de Massas , Nanotubos de Carbono , Polímeros , Microextração em Fase Sólida
11.
Talanta ; 269: 125394, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37980173

RESUMO

Saliva has significantly evolved as a diagnostic fluid in recent years, giving a non-invasive alternative to blood analysis. A high protein concentration in saliva is delivered directly from the bloodstream, making it a "human mirror" that reflects the body's physiological state. It plays an essential role in detecting diseases in biomedical and fitness monitoring. Molecularly imprinted polymers (MIPs) are biomimetic materials with custom-designed synthetic recognition sites that imitate biological counterparts renowned for sensitive analyte detection. This paper reviews the progress made in research about MIP biosensors for detecting saliva biomarkers. Specifically, we investigate the link between saliva biomarkers and various diseases, providing detailed insights into the corresponding biosensors. Furthermore, we discuss the principles of molecular imprinting for disease diagnostics and application analysis, including recent advances in integrated MIP-sensor technologies for high-affinity analyte detection in saliva. Notably, these biosensors exhibit high discrimination, allowing for the detection of saliva biomarkers linked explicitly to chronic stress disorders, diabetes, cancer, bacterial or viral-induced illnesses, and exposure to illicit toxic substances or tobacco smoke. Our findings indicate that MIP-based biosensors match and perhaps surpass their counterparts featuring integrated natural antibodies in terms of stability, signal-to-noise ratios, and detection limits. Additionally, we highlight the design of MIP coatings, strategies for synthesizing polymers, and the integration of advanced biodevices. These tailored biodevices, designed to assess various salivary biomarkers, are emerging as promising screening or diagnostic tools for real-time monitoring and self-health management, improving quality of life.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Humanos , Saliva/química , Qualidade de Vida , Polímeros , Biomarcadores/análise
12.
Phytomedicine ; 129: 155604, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38614042

RESUMO

BACKGROUND: Bone deficiency-related diseases caused by various factors have disrupted the normal function of the skeleton and imposed a heavy burden globally, urgently requiring potential new treatments. The multi-faceted role of compounds like ginsenosides and their interaction with the bone microenvironment, particularly osteoblasts can promote bone formation and exhibit anti-inflammatory, vascular remodeling, and antibacterial properties, holding potential value in the treatment of bone deficiency-related diseases and bone tissue engineering. PURPOSE: This review summarizes the interaction between ginsenosides and osteoblasts and the bone microenvironment in bone formation, including vascular remodeling and immune regulation, as well as their therapeutic potential and toxicity in the broad treatment applications of bone deficiency-related diseases and bone tissue engineering, to provide novel insights and treatment strategies. METHODS: The literature focusing on the mechanisms and applications of ginsenosides in promoting bone formation before March 2024 was searched in PubMed, Web of Science, Google Scholar, Scopus, and Science Direct databases. Keywords such as "phytochemicals", "ginsenosides", "biomaterials", "bone", "diseases", "bone formation", "microenvironment", "bone tissue engineering", "rheumatoid arthritis", "periodontitis", "osteoarthritis", "osteoporosis", "fracture", "toxicology", "pharmacology", and combinations of these keywords were used. RESULTS: Ginsenoside monomers regulate signaling pathways such as WNT/ß-catenin, FGF, and BMP/TGF-ß, stimulating osteoblast generation and differentiation. It exerts angiogenic and anti-inflammatory effects by regulating the bone surrounding microenvironment through signaling such as WNT/ß-catenin, NF-κB, MAPK, PI3K/Akt, and Notch. It shows therapeutic effects and biological safety in the treatment of bone deficiency-related diseases, including rheumatoid arthritis, osteoarthritis, periodontitis, osteoporosis, and fractures, and bone tissue engineering by promoting osteogenesis and improving the microenvironment of bone formation. CONCLUSION: The functions of ginsenosides are diverse and promising in treating bone deficiency-related diseases and bone tissue engineering. Moreover, potential exists in regulating the bone microenvironment, modifying biomaterials, and treating inflammatory-related bone diseases and dental material applications. However, the mechanisms and effects of some ginsenoside monomers are still unclear, and the lack of clinical research limits their clinical application. Further exploration and evaluation of the potential of ginsenosides in these areas are expected to provide more effective methods for treating bone defects.


Assuntos
Ginsenosídeos , Osteoblastos , Osteogênese , Ginsenosídeos/farmacologia , Humanos , Osteogênese/efeitos dos fármacos , Animais , Osteoblastos/efeitos dos fármacos , Engenharia Tecidual/métodos , Osso e Ossos/efeitos dos fármacos
13.
J Photochem Photobiol B ; 258: 112999, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39126752

RESUMO

5-Aminolevulinic acid (5-ALA) is a prodrug of porphyrin IX (PpIX). Disadvantages of 5-ALA include poor stability, rapid elimination, poor bioavailability, and weak cell penetration, which greatly reduce the clinical effect of 5-ALA based photodynamic therapy (PDT). Presently, a novel targeting nanosystem was constructed using gold nanoparticles (AuNPs) as carriers loaded with a CSNIDARAC (CC9)-targeting peptide and 5-ALA via Au-sulphur and ionic bonds, respectively, and then wrapped in polylactic glycolic acid (PLGA) NPs via self-assembly to improve the antitumor effects and reduce the side effect. The successful preparation of ALA/CC9@ AuNPs-PLGA NPs was verified using ultraviolet-visible, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The analyses revealed good sphericity with a particle size of approximately140 nm, Zeta potential of 10.11 mV, and slow-controlled release characteristic in a weak acid environment. Confocal microscopy revealed targeting of NCL-H460 cells by NPs by actively internalising CC9 and avoiding the phagocytic action of RAW264.7 cells, and live fluorescence imaging revealed targeting of tumours in tumour-bearing mice. Compared to free 5-ALA, the nanosystem displayed amplified anticancer activity by increasing production of PpIX and reactive oxygen species to induce mitochondrial pathway apoptosis. Antitumor efficacy was consistently observed in three-dimensionally cultured cells as the loss of integrity of tumour balls. More potent anti-tumour efficacy was demonstrated in xenograft tumour models by decreased growth rate and increased tumour apoptosis. Histological analysis showed that this system was not toxic, with lowered liver toxicity of 5-ALA. Thus, ALA/CC9@AuNPs-PLGA NPs deliver 5-ALA via a carrier cascade, with excellent effects on tumour accumulation and PDT through passive enhanced permeability and retention action and active targeting. This innovative strategy for cancer therapy requires more clinical trials before being implemented.


Assuntos
Ácido Aminolevulínico , Ouro , Neoplasias Pulmonares , Nanopartículas Metálicas , Fotoquimioterapia , Ácido Aminolevulínico/química , Ácido Aminolevulínico/farmacologia , Ácido Aminolevulínico/uso terapêutico , Animais , Ouro/química , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Camundongos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Linhagem Celular Tumoral , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Portadores de Fármacos/química , Apoptose/efeitos dos fármacos , Ácido Láctico/química , Ácido Poliglicólico/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
14.
ACS Appl Mater Interfaces ; 16(22): 28147-28161, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38783481

RESUMO

Nonhealing infectious wounds, characterized by bacterial colonization, wound microenvironment destruction, and shape complexity, present an intractable problem in clinical practice. Inspired by LEGOs, building-block toys that can be assembled into desired shapes, we proposed the use of electrospray nano-micro composite sodium alginate (SA) microspheres with antibacterial and angiogenic properties to fill irregularly shaped wounds instantly. Specifically, porous poly(lactic-co-glycolic acid) (PLGA) microspheres (MSs) encapsulating basic fibroblast growth factor (bFGF) were produced by a water-in-oil-in-water double-emulsion method. Then, bFGF@MSs were blended with the SA solution containing ZIF-8 nanoparticles. The resultant solution was electrosprayed to obtain nano-micro composite microspheres (bFGF@MS/ZIF-8@SAMSs). The composite MSs' size could be regulated by PLGA MS mass proportion and electrospray voltage. Moreover, bFGF, a potent angiogenic agent, and ZIF-8, bactericidal nanoparticles, were found to release from bFGF@MS/ZIF-8@SAMSs in a controlled and sustainable manner, which promoted cell proliferation, migration, and tube formation and killed bacteria. Through experimentation on rat models, bFGF@MS/ZIF-8@SAMSs were revealed to adapt to wound shapes and accelerate infected wound healing because of the synergistic effects of antibacterial and angiogenic abilities. In summation, this study developed a feasible approach to prepare bioactive nano-micro MSs as building blocks that can fill irregularly shaped infected wounds and improve healing.


Assuntos
Alginatos , Antibacterianos , Fator 2 de Crescimento de Fibroblastos , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Cicatrização , Alginatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Ratos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Fator 2 de Crescimento de Fibroblastos/química , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos , Masculino , Escherichia coli/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Células Endoteliais da Veia Umbilical Humana , Testes de Sensibilidade Microbiana , Proliferação de Células/efeitos dos fármacos , Ácido Glucurônico/química , Ácido Glucurônico/farmacologia
15.
Animal Model Exp Med ; 7(4): 562-569, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38158631

RESUMO

INTRODUCTION: This study aimed to establish an animal model of open abdomen (OA) through temporary abdominal closure via different techniques. METHODS: Adult male Sprague-Dawley rats were randomly divided into three groups: group A (OA with polypropylene mesh alone); group B (OA with polypropylene mesh combined with a patch); and group C (OA with polypropylene mesh and a sutured patch). Vital signs, pathophysiological changes, and survival rates were closely monitored in the rats for 7 days after surgery. Abdominal X-rays and histopathological examinations were performed to assess abdominal organ changes and wound healing. RESULTS: The results showed no significant difference in mortality rates among the three groups (p > 0.05). However, rats in group B exhibited superior overall condition, cleaner wounds, and a higher rate of wound healing compared to the other groups (p < 0.05). Abdominal X-rays indicated that varying degrees of distal intestinal obstruction in all groups. Histopathological examinations revealed fibrous hyperplasia, inflammatory cell infiltration, neovascularization, and collagen deposition in all groups. Group B demonstrated enhanced granulation tissue generation, neovascularization, and collagen deposition compared to the other groups (p < 0.05). CONCLUSIONS: Polypropylene mesh combined with patches is the most suitable method for establishing an animal model of OA. This model successfully replicated the pathological and physiological changes in postoperative patients with OA, specifically the progress of abdominal skin wound healing. It provides a practical and reliable animal model for OA research.


Assuntos
Modelos Animais de Doenças , Ratos Sprague-Dawley , Telas Cirúrgicas , Cicatrização , Animais , Masculino , Ratos , Polipropilenos , Técnicas de Abdome Aberto , Abdome/cirurgia , Abdome/diagnóstico por imagem
16.
ACS Appl Mater Interfaces ; 16(23): 30430-30442, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38814614

RESUMO

Patients with open abdominal (OA) wounds have a mortality risk of up to 30%, and the resulting disabilities would have profound effects on patients. Here, we present a novel double-sided adhesive tape developed for the management of OA wounds. The tape features an asymmetrical structure and employs an acellular dermal matrix (ADM) with asymmetric wettability as a scaffold. It is constructed by integrating a tissue-adhesive hydrogel composed of polydopamine (pDA), quaternary ammonium chitosan (QCS), and acrylic acid cross-linking onto the bottom side of the ADM. Following surface modification with pDA, the ADM would exhibit characteristics resistant to bacterial adhesion. Furthermore, the presence of a developed hydrogel ensures that the tape not only possesses tissue adhesiveness and noninvasive peelability but also effectively mitigates damage caused by oxidative stress. Besides, the ADM inherits the strength of the skin, imparting high burst pressure tolerance to the tape. Based on these remarkable attributes, we demonstrate that this double-sided (D-S) tape facilitates the repair of OA wounds, mitigates damage to exposed intestinal tubes, and reduces the risk of intestinal fistulae and complications. Additionally, the D-S tape is equally applicable to treating other abdominal injuries, such as gastric perforations. It effectively seals the perforation, promotes injury repair, and prevents the formation of postoperative adhesions. These notable features indicate that the presented double-sided tape holds significant potential value in the biomedical field.


Assuntos
Traumatismos Abdominais , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Adesivos Teciduais/química , Adesivos Teciduais/farmacologia , Quitosana/química , Quitosana/farmacologia , Camundongos , Polímeros/química , Polímeros/farmacologia , Humanos , Indóis/química , Indóis/farmacologia , Cicatrização/efeitos dos fármacos , Pressão , Masculino , Ratos
17.
Adv Healthc Mater ; 12(29): e2301313, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37220875

RESUMO

The problems of step effects, supporting material waste, and conflict between flexibility and toughness for 3D printed intestinal fistula stents are not yet resolved. Herein, the fabrication of a support-free segmental stent with two types of thermoplastic polyurethane (TPU) using a homemade multi-axis and multi-material conformal printer guided with advanced whole model path planning is demonstrated. One type of TPU segment is soft to increase elasticity, and the other is used to achieve toughness. Owing to advancements in stent design and printing, the obtained stents present three unprecedented properties compared to previous three-axis printed stents: i) Overcoming step effects; ii) Presenting comparable axial flexibility to a stent made of a single soft TPU 87A material, thus increasing the feasibility of implantation; and iii) Showing equivalent radial toughness to a stent made of a single hard TPU 95A material. Hence, the stent can resist the intestinal contractive force and maintain intestinal continuity and patency. Through implanting such stents to the rabbit intestinal fistula models, therapeutic mechanisms of reducing fistula output and improving nutritional states and intestinal flora abundance are revealed. Overall, this study develops a creative and versatile method to improve the poor quality and mechanical properties of medical stents.


Assuntos
Fístula Intestinal , Stents , Animais , Coelhos , Poliuretanos , Fenômenos Mecânicos , Impressão Tridimensional
18.
Genes (Basel) ; 13(11)2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36360321

RESUMO

Chinese cabbage, which is a cold season crop, can still be damaged at an overly low temperature. It is crucial to study the mechanism of the resistance to low temperature of Chinese cabbage. In this study, the Chinese cabbage 'XBJ' was used as the material, and nine different low temperatures and control samples were treated. Using RNA-seq and lignin content determination, we analyzed 27 samples, and the stained sections of them were observed. A total of 8845 genes were screened for the WGCNA analysis, yielding 17 modules. The GO and KEGG analyses of the modules was highly associated with a low-temperature treatment. The pathways such as 'starch and sucrose metabolism' and 'plant hormone signal transduction' were enriched in modules related to low temperature. Interestingly, L-15DAT-associated MEcoral2 was found to have 14 genes related to the 'lignin biosynthetic process' in the GO annotation. The combination of the determination of the lignin content and the treatment of the stained sections showed that the lignin content of the low-temperatures samples were indeed higher than that of the control. We further explored the expression changes of the lignin synthesis pathway and various genes and found that low temperature affects the expression changes of most genes in the lignin synthesis pathway, leading to the speculation that the lignin changes at low temperature are a defense mechanism against low temperatures. The 29 BrCOMT gene sequence derived from the RNA-seq was non-conserved, and eight BrCOMT genes were differentially expressed. This study provides a new insight into how lignin is affected by low temperature.


Assuntos
Brassica , Lignina , Lignina/genética , Temperatura , Regulação da Expressão Gênica de Plantas , Transcriptoma/genética , Perfilação da Expressão Gênica , Brassica/genética , China
19.
J Spinal Disord Tech ; 24(6): E49-56, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21685804

RESUMO

STUDY DESIGN: An in vitro biomechanical cadaver study. OBJECTIVES: To evaluate the pull-out strength after 5000 cyclic loading among 4 revision techniques for the loosened iliac screw using corticocancellous bone, longer screw, traditional cement augmentation, and boring cement augmentation. SUMMARY OF BACKGROUND DATA: Iliac screw loosening is still a clinical problem for lumbo-iliac fusion. Although many revision techniques using corticocancellous bone, larger screw, and polymethylmethacrylate (PMMA) augmentation were applied in repairing pedicle screw loosening, their biomechanical effects on the loosened iliac screw remain undetermined. METHODS: Eight fresh human cadaver pelvises with the bone mineral density values ranging from 0.83 to 0.97 g/cm were adopted in this study. After testing the primary screw of 7.5 mm diameter and 70 mm length, 4 revision techniques were sequentially established and tested on the same pelvis as follows: corticocancellous bone, longer screw with 100 mm length, traditional PMMA augmentation, and boring PMMA augmentation. The difference of the boring technique from traditional PMMA augmentation is that PMMA was injected into the screw tract through 3 boring holes of outer cortical shell without removing the screw. On an MTS machine, after 5000 cyclic compressive loading of -200∼-500 N to the screw head, axial maximum pull-out strengths of the 5 screws were measured and analyzed. RESULTS: The pull-out strengths of the primary screw and 4 revised screws with corticocancellous bone, longer screw and traditional and boring PMMA augmentation were 1167 N, 361 N, 854 N, 1954 N, and 1820 N, respectively. Although longer screw method obtained significantly higher pull-out strength than corticocancellous bone (P<0.05), the revised screws using these 2 techniques exhibited notably lower pull-out strength than the primary screw and 2 PMMA-augmented screws (P<0.05). Either traditional or boring PMMA screw showed obviously higher pull-out strength than the primary screw (P<0.05); however, no significant difference of pull-out strength was detected between the 2 PMMA screws (P>0.05). CONCLUSIONS: Wadding corticocancellous bone and increasing screw length failed to provide sufficient anchoring strength for a loosened iliac screw; however, both traditional and boring PMMA-augmented techniques could effectively increase the fixation strength. On the basis of the viewpoint of minimal invasion, the boring PMMA augmentation may serve as a suitable salvage technique for iliac screw loosening.


Assuntos
Cimentos Ósseos , Parafusos Ósseos , Ílio/cirurgia , Vértebras Lombares/cirurgia , Falha de Prótese , Idoso , Fenômenos Biomecânicos , Feminino , Humanos , Fixadores Internos , Masculino , Pessoa de Meia-Idade , Reoperação
20.
Nanomaterials (Basel) ; 11(10)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34684930

RESUMO

Titanium (Ti) and its alloys offer favorable biocompatibility, mechanical properties and corrosion resistance, which makes them an ideal material choice for dental implants. However, the long-term success of Ti-based dental implants may be challenged due to implant-related infections and inadequate osseointegration. With the development of nanotechnology, nanoscale modifications and the application of nanomaterials have become key areas of focus for research on dental implants. Surface modifications and the use of various coatings, as well as the development of the controlled release of antibiotics or proteins, have improved the osseointegration and soft-tissue integration of dental implants, as well as their antibacterial and immunomodulatory functions. This review introduces recent nano-engineering technologies and materials used in topographical modifications and surface coatings of Ti-based dental implants. These advances are discussed and detailed, including an evaluation of the evidence of their biocompatibility, toxicity, antimicrobial activities and in-vivo performances. The comparison between these attempts at nano-engineering reveals that there are still research gaps that must be addressed towards their clinical translation. For instance, customized three-dimensional printing technology and stimuli-responsive, multi-functional and time-programmable implant surfaces holds great promise to advance this field. Furthermore, long-term in vivo studies under physiological conditions are required to ensure the clinical application of nanomaterial-modified dental implants.

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