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1.
Adv Healthc Mater ; : e2401305, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767216

RESUMO

Combining the detection of tumor protein markers with the capture of circulating tumor cells (CTCs) represents an ultra-promising approach for early tumor detection. However, current methodologies have not yet achieved the necessary low detection limits and efficient capture. Here, we introduced a novel polypyrrole nanotentacles sensing platform featuring anemone-like structures capable of simultaneously detecting protein biomarkers and capturing CTCs. The incorporation of nanotentacles significantly enhanced the electrode surface area, providing abundant active sites for antibody binding. This enhancement allowed detecting nucleus matrix protein22 (NMP22) and bladder tumor antigen (BTA) with 2.39 and 3.12 pg/mL detection limit, respectively. Furthermore, our developed sensing platform effectively captured MCF-7 cells in blood samples with a detection limit of fewer than 10 cells/mL, attributed to the synergistic multivalent binding facilitated by the specific recognition antibodies and the positive charge on the nanotentacles surface. This sensing platform demonstrated excellent detection capabilities and outstanding capture efficiency, offering a simple, accurate, and efficient strategy for early tumor detection. This article is protected by copyright. All rights reserved.

2.
Adv Healthc Mater ; : e2303836, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507269

RESUMO

Chronic diabetic wounds pose significant challenges due to uncontrolled bacterial infections, prolonged inflammation, and impaired angiogenesis. The rapid advancement of photo-responsive antibacterial therapy showed promise in addressing these complex issues, particularly utilizing 2D heterojunction materials, which offer unique properties. Herein, we designed an in situ sprayed Bi/BiOCl 0D/2D heterojunction composite fibrin gel with the characteristics of rapid formation and effective near-infrared activation for the treatment of non-healing diabetes-infected wounds. The sprayed composite gel can provide protective shielding for skin tissues and promote endothelial cell proliferation, vascularization, and angiogenesis. The Bi/BiOCl 0D/2D heterojunction, with its localized surface plasmon resonance (LSPR), can overcome the wide bandgap limitation of BiOCl, enhancing the generation of local heat and reactive oxygen species under near-infrared irradiation. This facilitated bacterial elimination and reduced inflammation, supporting the accelerated healing of diabetes-infected wounds. Our study underscores the potential of LSPR-enhanced heterojunctions as advanced wound therapies for chronic diabetic wounds. This article is protected by copyright. All rights reserved.

3.
J Nanobiotechnology ; 22(1): 54, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326903

RESUMO

The treatment of critical-size bone defects with irregular shapes remains a major challenge in the field of orthopedics. Bone implants with adaptability to complex morphological bone defects, bone-adhesive properties, and potent osteogenic capacity are necessary. Here, a shape-adaptive, highly bone-adhesive, and ultrasound-powered injectable nanocomposite hydrogel is developed via dynamic covalent crosslinking of amine-modified piezoelectric nanoparticles and biopolymer hydrogel networks for electrically accelerated bone healing. Depending on the inorganic-organic interaction between the amino-modified piezoelectric nanoparticles and the bio-adhesive hydrogel network, the bone adhesive strength of the prepared hydrogel exhibited an approximately 3-fold increase. In response to ultrasound radiation, the nanocomposite hydrogel could generate a controllable electrical output (-41.16 to 61.82 mV) to enhance the osteogenic effect in vitro and in vivo significantly. Rat critical-size calvarial defect repair validates accelerated bone healing. In addition, bioinformatics analysis reveals that the ultrasound-responsive nanocomposite hydrogel enhanced the osteogenic differentiation of bone mesenchymal stem cells by increasing calcium ion influx and up-regulating the PI3K/AKT and MEK/ERK signaling pathways. Overall, the present work reveals a novel wireless ultrasound-powered bone-adhesive nanocomposite hydrogel that broadens the therapeutic horizons for irregular bone defects.


Assuntos
Osteogênese , Fosfatidilinositol 3-Quinases , Ratos , Animais , Nanogéis , Osso e Ossos/diagnóstico por imagem , Hidrogéis/farmacologia
4.
Bioact Mater ; 34: 381-400, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38269309

RESUMO

Preventing local tumor recurrence while promoting bone tissue regeneration is an urgent need for osteosarcoma treatment. However, the therapeutic efficacy of traditional photosensitizers is limited, and they lack the ability to regenerate bone. Here, a piezo-photo nanoheterostructure is developed based on ultrasmall bismuth/strontium titanate nanocubes (denoted as Bi/SrTiO3), which achieve piezoelectric field-driven fast charge separation coupling with surface plasmon resonance to efficiently generate reactive oxygen species. These hybrid nanotherapeutics are integrated into injectable biopolymer hydrogels, which exhibit outstanding anticancer effects under the combined irradiation of NIR and ultrasound. In vivo studies using patient-derived xenograft models and tibial osteosarcoma models demonstrate that the hydrogels achieve tumor suppression with efficacy rates of 98.6 % and 67.6 % in the respective models. Furthermore, the hydrogel had good filling and retention capabilities in the bone defect region, which exerted bone repair therapeutic efficacy by polarizing and conveying electrical stimuli to the cells under mild ultrasound radiation. This study provides a comprehensive and clinically feasible strategy for the overall treatment and tissue regeneration of osteosarcoma.

5.
Mater Horiz ; 10(11): 4903-4913, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37750251

RESUMO

Conversion between mechanical and electrical cues is usually considered unidirectional in cells with cardiomyocytes being an exception. Here, we discover a material-induced external electric field (Eex) triggers an electro-mechanical coupling feedback loop in cells other than cardiomyocytes, human umbilical vein endothelial cells (HUVECs), by opening their mechanosensitive Piezo1 channels. When HUVECs are cultured on patterned piezoelectric materials, the materials generate Eex (confined at the cellular scale) to polarize intracellular calcium ions ([Ca2+]i), forming a built-in electric field (Ein) opposing Eex. Furthermore, the [Ca2+]i polarization stimulates HUVECs to shrink their cytoskeletons, activating Piezo1 channels to induce influx of extracellular Ca2+ that gradually increases Ein to balance Eex. Such an electro-mechanical coupling feedback loop directs pre-angiogenic activities such as alignment, elongation, and migration of HUVECs. Activated calcium dynamics during the coupling further modulate the downstream angiogenesis-inducing eNOS/NO pathway. These findings lay a foundation for developing new ways of electrical stimulation-based disease treatment.


Assuntos
Cálcio , Humanos , Cálcio/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Cultivadas , Íons/metabolismo
6.
Nanoscale Adv ; 5(12): 3304-3315, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37325540

RESUMO

Carbon dots (CDs), as new carbon nanomaterials, have potential applications in multiple fields due to their superior optical properties, good biocompatibility, and easy preparation. However, CDs are typically an aggregation-caused quenching (ACQ) material, which has a huge limitation on the practical application of CDs. To solve this problem, in this paper, CDs were prepared by the solvothermal method using citric acid and o-phenylenediamine as precursors and dimethylformamide as solvent. Then using CDs as nucleating agents, solid-state green fluorescent CDs were synthesized by in situ growth of nano-hydroxyapatite (HA) crystals on the surface of CDs. The results show that CDs are stably dispersed single-particlely in the form of bulk defects in the nano-HA lattice matrices with a dispersion concentration of 3.10%, and solid-state green fluorescence of CDs is achieved with a stable emission wavelength peak position near 503 nm, which provides a new solution to the ACQ problem. CDs-HA nanopowders were further used as LED phosphors to obtain bright green LEDs. In addition, CDs-HA nanopowders showed excellent performance in cell imaging (mBMSCs and 143B) applications, which provides a new scheme for further applications of CDs in the field of cell imaging and even in vivo imaging.

7.
Adv Healthc Mater ; 12(17): e2300064, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36854114

RESUMO

Insufficient angiogenesis frequently occurs after the implantation of orthopedic materials, which greatly increases the risk of bone defect reconstruction failure. Therefore, the development of bone implant with improved angiogenic properties is of great importance. Mimicking the extracellular matrix clues provides a more direct and effective strategy to modulate angiogenesis. Herein, inspired by the bioelectrical characteristics of the bone microenvironment, a piezoelectric bioactive glasses composite (P-KNN/BG) based on the incorporation of polarized potassium sodium niobate is constructed, which could effectively promote angiogenesis. It is found that P-KNN/BG has exceptional wireless electrical stimulation performance and sustained active ions release. In vitro cell experiments reveal that P-KNN/BG enhances endothelial cell adhesion, migration, and differentiation via activating the eNOS/NO signaling pathway, which might be contributed to cell membrane hyperpolarization induced by wireless electrical stimulation increase the influx of active ions into the cells. In vivo chick chorioallantoic membrane experiment demonstrates that P-KNN/BG shows excellent pro-angiogenic capacity and biocompatibility. This work broadens the current understanding of bioactive materials with bionic electrical properties, which brings new insights into the clinical treatment of bone defect repair.


Assuntos
Osso e Ossos , Neovascularização Fisiológica , Células Endoteliais , Adesão Celular , Íons/farmacologia , Osteogênese , Vidro
8.
Adv Healthc Mater ; 12(13): e2203306, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36708290

RESUMO

Photothermal hydrogel adhesives have yielded promising results for wound closure and infected wound treatment in recent years. However, photothermal hydrogel bioadhesives with on-demand removability without additional nanomaterials-based photothermal agents have rarely been reported in the literature. In this work, an injectable intrinsic photothermal hydrogel bioadhesive with an on-demand removal trait is developed through dynamic cross-linking of gelatin (Gel), tannic acid (TA) quinone, and borax for closing skin incisions and accelerating methicillin-resistant Staphylococcus aureus (MRSA) infected wound healing. The TA quinone containing polyphenol and quinone groups with multifunctional adhesiveness and intrinsic photothermal performance confer the hydrogel adhesive with near-infrared (NIR) responsive antibacterial activity. The cross-linking of pH-sensitive boronic ester (polyphenol-B) and Schiff base bonds endow the hydrogel with great self-healing capacity and on-demand removability. Moreover, the hydrogel possesses good biocompatibility, injectability, and hemostasis. The in vivo experiment in a rat cutaneous incision model and full-thickness MRSA-infected wound model indicate that the smart hydrogel can close wounds efficiently and treat infected ones, demonstrating its superiority in noninvasive treatment of cutaneous incisions and enhancing infected full-thickness wound healing.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Animais , Ratos , Hidrogéis/farmacologia , Antibacterianos/farmacologia , Polifenóis , Quinonas , Cicatrização
9.
ACS Nano ; 16(12): 20770-20785, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36412574

RESUMO

Preventing local tumor recurrence and simultaneously improving bone-tissue regeneration are in great demand for osteosarcoma therapy. However, the current therapeutic implants fail to selectively suppress tumor growth and enhance osteogenesis, and antitumor therapy may compromise osseointegration of the bone implant. Here, based on the different responses of bone tumor cells and osteoblasts to different electric stimulations, we constructed ferroelectric BaTiO3 nanorod arrays (NBTO) on the surface of titanium implants with switchable dynamic and static electrical stimulation for selective bone-tumor therapy and bone tissue regeneration. Polarized NBTO (PNBTO) generated a sustained dynamic electrical stimulus in response to wireless ultrasonic irradiation ("switch-on"), which disrupted the orientation of the spindle filaments of the tumor cell, blocked the G2/M phase of mitosis, and ultimately led to tumor cell death, whereas it had almost no cytotoxic effect on normal bone cells. Under the switch-off state, PNBTO with a high surface potential provided static electrical stimulation, accelerating osteogenic differentiation of mesenchymal stem cells and enhancing the quality of bone regeneration both in vitro and in vivo. This study broadens the biomedical potential of electrical stimulation therapy and provides a comprehensive and clinically feasible strategy for the overall treatment and tissue regeneration in osteosarcoma.


Assuntos
Osteogênese , Osteossarcoma , Humanos , Osso e Ossos , Próteses e Implantes , Diferenciação Celular , Osteossarcoma/terapia , Estimulação Elétrica , Titânio/farmacologia
10.
ACS Appl Mater Interfaces ; 14(39): 45032-45041, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36153948

RESUMO

Triple-negative breast cancer (TNBC) is an aggressive BC subtype with a higher metastatic rate and a worse 5-year survival ratio than the other BC. It is an urgent need to develop a noninvasive treatment with high efficiency to resist TNBC cell proliferation and invasion. Internal wireless electric stimulation (ES) based on piezoelectric materials is an emerging noninvasive strategy, with adjustable ES intensity and excellent biosafety. In this study, three different barium titanate nanoparticles (BTNPs) with different crystal phases and piezoelectric properties were studied. Varying intensities of internal ES were generated from the three BTNPs (i.e., BTO, U-BTO, P-BTO). In vitro tests revealed that the internal ES from BTNPs was efficient at reducing the proliferative potential of cancer cells, particularly BC cells. In vitro experiments on MDA-MB-231, a typical TNBC cell line, further revealed that the internal wireless ES from BTNPs significantly inhibited cell growth and migration up to about 82% and 60%, respectively. In vivo evaluation of MDA-MB-231 tumor-bearing mice indicated that internal ES not only resisted almost 70% tumor growth but also significantly inhibited lung metastasis. More importantly, in vitro and in vivo studies demonstrated a favorable correlation between the anticancer impact and the intensities of ES. The underlying mechanism of MDA-MB-231 cell proliferation and metastasis inhibition caused by internal ES was also investigated. In summary, our results revealed the effect and mechanism of internal ES from piezoelectric nanoparticles on TNBC cell proliferation and migration regulation and proposed a promising noninvasive therapeutic strategy for TNBC with minimal side effects while exhibiting good therapeutic efficiency.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Animais , Bário/farmacologia , Bário/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Estimulação Elétrica , Humanos , Camundongos , Nanopartículas/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
11.
ACS Biomater Sci Eng ; 8(6): 2419-2427, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35642535

RESUMO

Postsurgical infection of orthopedic fixation materials is considered to be the main cause of fixation failure. To address the problem, clinical treatment often relies on long-term antibiotics, secondary surgery, and so forth, which cause pain and suffering to patients. Constructing a light-responsive surface structure on the implant has attracted widespread attention for the management of postsurgical infections because of its noninvasiveness and controllability. Nevertheless, the application of light-responsive structures on implants is still limited by their unsafety and instability. In this work, a black titanium oxide layer with a multilevel structure and lattice defects was in situ constructed on a titanium alloy through pulsed laser ablation treatment. Under the synergistic effect of the multilevel structure and crystal defects, the surface of the titanium alloy exhibited good near-infrared light-responsive photothermal ability. The black titanium oxide multilevel structure reached high antibacterial efficiencies of about 99.37 and 99.29% against Staphylococcus aureus and Escherichia coli under 10 min near-infrared light irradiation. Furthermore, the black titanium oxide layer possessed similar biocompatibility compared with the titanium alloy. This near-infrared light-responsive photothermal therapy based on the construction of a multilevel structure and introduction of lattice defects provides an effective strategy for clinical postsurgical infections of orthopedic fixation.


Assuntos
Ligas , Titânio , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli , Humanos , Terapia Fototérmica , Titânio/química , Titânio/farmacologia
12.
ACS Biomater Sci Eng ; 8(7): 3078-3086, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35767822

RESUMO

Pressure injuries/pressure ulcers (PIs/PUs) are a critical global healthcare issue and represent a considerable burden on healthcare resources. Prevention of PIs/PUs is the least costly approach and minimizes the patient suffering compared with treatment. Besides, sustained tissue load alleviation and microenvironment management are the most crucial properties for dressings in PI/PU prevention. Hydrogel dressings have attracted a lot of attention to prevent PIs/PUs because of their unique mechanical properties and ability to manage the microenvironment of skin. However, auxiliary prophylaxis and early treatment of PIs/PUs remain a challenge and an acute clinical demand. Here, we report on an electroactive hydrogel with large stretchability (∼380%) and skinlike ductility, and Young's modulus (0.48 ± 0.03 MPa) matches that of human skin (0.5-1.95 MPa). The hydrogel displayed piezoelectric properties and mechanical-electric response stability and sensitivity. Our results indicated that the hydrogel was able to promote in vitro angiogenesis under piezoelectric stimulation and exhibited biocompatibility, which has the potential for forming fine vessels at the damaged sites of PIs/PUs. Furthermore, finite element analysis and pressure dispersion experiments demonstrated that the hydrogel was suitable for preventing PIs/PUs by redistributing force, reducing tissue distortion, and maintaining the microenvironment for skin. This work offers a new strategy for designing and evaluating the dressing for prophylaxis and the early treatment of PIs/PUs.


Assuntos
Úlcera por Pressão , Bandagens , Humanos , Hidrogéis/uso terapêutico , Úlcera por Pressão/tratamento farmacológico , Úlcera por Pressão/prevenção & controle , Supuração/tratamento farmacológico
13.
Bioact Mater ; 18: 399-408, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35415302

RESUMO

Pathological angiogenesis frequently occurs in tumor tissue, limiting the efficiency of chemotherapeutic drug delivery and accelerating tumor progression. However, traditional vascular normalization strategies are not fully effective and limited by the development of resistance. Herein, inspired by the intervention of endogenous bioelectricity in vessel formation, we propose a wireless electrical stimulation therapeutic strategy, capable of breaking bioelectric homeostasis within cells, to achieve tumor vascular normalization. Polarized barium titanate nanoparticles with high mechano-electrical conversion performance were developed, which could generate pulsed open-circuit voltage under low-intensity pulsed ultrasound. We demonstrated that wireless electrical stimulation significantly inhibited endothelial cell migration and differentiation in vitro. Interestingly, we found that the angiogenesis-related eNOS/NO pathway was inhibited, which could be attributed to the destruction of the intracellular calcium ion gradient by wireless electrical stimulation. In vivo tumor-bearing mouse model indicated that wireless electrical stimulation normalized tumor vasculature by optimizing vascular structure, enhancing blood perfusion, reducing vascular leakage, and restoring local oxygenation. Ultimately, the anti-tumor efficacy of combination treatment was 1.8 times that of the single chemotherapeutic drug doxorubicin group. This work provides a wireless electrical stimulation strategy based on the mechano-electrical conversion performance of piezoelectric nanoparticles, which is expected to achieve safe and effective clinical adjuvant treatment of malignant tumors.

14.
Small Methods ; 6(5): e2101513, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35246966

RESUMO

The vulnerability of hydrogel electronic materials to mechanical damage due to their soft nature has necessitated the development of self-repairing hydrogel electronics. However, the development of such material with underwater self-repairing capability as well as excellent mechanical properties for application in aquatic environments is highly challenging and has not yet been fully realized. This study designs a tough and highly efficient underwater self-repairing supramolecular hydrogel by synergistically combining weak hydrogen bonds (H-bonds) and strong dipole-dipole interactions. The resultant hydrogel has high stretchability (up to 700%) and toughness (4.45 MJ m-3 ), and an almost 100% fast strain self-recovery (10 min). The underwater healing process is rapid and autonomous (98% self-repair efficiency after 1 h of healing). Supramolecular hydrogels can be developed as soft electronic sensors for physiological signal detection (gestures, breathing, microexpression, and vocalization) and real-time underwater communication (Morse code). Importantly, the hydrogel sensor can function underwater after mechanical damage because of its highly efficient underwater self-repairing capability.


Assuntos
Eletrônica , Hidrogéis , Hidrogéis/química , Ligação de Hidrogênio
15.
Adv Healthc Mater ; 11(1): e2101556, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34648694

RESUMO

The critical effects that impair diabetic wound healing are characterized by poor vascularization and severe peripheral neuropathy. Current management strategies for diabetic wound healing are unsatisfactory, due to the paucity of neurovascular regeneration at the wound site. Importantly, conductivity in skin tissue is reported to be essential for modulating myriad biological processes especially vascular and nerve regeneration. Herein, an extracellular matrix (ECM)-based conductive dressing is synthesized from an interpenetrating polymer network hydrogel composed of gelatin methacryloyl, oxidized chondroitin sulfate (OCS), and OCS-polypyrrole conductive nanoparticles that can promote diabetic wound repairing by enhancing local neurovascular regeneration. The conductive hydrogels combine the advantageous features of water-swollen hydrogels with conductive polymers (CPs) to provide tissue-matching electrical conductivity and mechanical properties for neurovascular regeneration. In vitro and in vivo studies show that the conductive hydrogel can promote neurovascular regeneration by increasing intracellular Ca2+ concentration, which subsequently promotes phosphorylation of proteins in the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) and mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathways. Furthermore, the conductive hydrogel stimulates full-thickness diabetic wound repair on day 14 by promoting local neurovascular regeneration and collagen deposition. These findings corroborate that the ECM-based conductive interpenetrating network hydrogel dressing significantly promotes wound repairing due to its neurovascular regeneration properties, suggesting that they are suitable candidates for diabetic wound repair.


Assuntos
Diabetes Mellitus , Hidrogéis , Condutividade Elétrica , Matriz Extracelular , Gelatina , Humanos , Metacrilatos , Fosfatidilinositol 3-Quinases , Polímeros , Pirróis
16.
Bioact Mater ; 6(9): 2754-2766, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33665507

RESUMO

The host immune response effecting on biomaterials is critical to determine implant fates and bone regeneration property. Bone marrow stem cells (BMSCs) derived exosomes (Exos) contain multiple biosignal molecules and have been demonstrated to exhibit immunomodulatory functions. Herein, we develop a BMSC-derived Exos-functionalized implant to accelerate bone integration by immunoregulation. BMSC-derived Exos were reversibly incorporated on tannic acid (TA) modified sulfonated polyetheretherketone (SPEEK) via the strong interaction of TA with biomacromolecules. The slowly released Exos from SPEEK can be phagocytosed by co-cultured cells, which could efficiently improve the biocompatibilities of SPEEK. In vitro results showed the Exos loaded SPEEK promoted macrophage M2 polarization via the NF-κB pathway to enhance BMSCs osteogenic differentiation. Further in vivo rat air-pouch model and rat femoral drilling model assessment of Exos loaded SPEEK revealed efficient macrophage M2 polarization, desirable new bone formation, and satisfactory osseointegration. Thus, BMSC-derived Exos-functionalized implant exerted osteoimmunomodulation effect to promote osteogenesis.

17.
Environ Sci Pollut Res Int ; 27(31): 38849-38860, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32632688

RESUMO

Well-defined targets for nitrogen (N) release into the local environment are essential for water management in creeks, but difficulties often arise from working with data that are too sparse to achieve reliable evaluations. Here, a simulation-optimization approach based on the QUAL2K model was developed to put forward strategies for nitrogen pollution control in a creek with sparse data in Shixi Creek, southeast China. The model showed good agreement with field observations from 22 sampling sites sampled over the period from March 2017 to February 2019, with normalized objective function (NOF) less than 0.360. Based on this model, the water pollutant sources in the creek were distinguished and analyzed. Rural sewage discharge in Shixi Creek was the major factor threatening water quality in the stream. Seasonal variations may influence the transformation of riverine N. To make more than 80% of the area in Shixi Creek meet the water quality standard of grade III, an optimized approach is to reduce more than 55% of the N pollution from point source pollution and 10% from nonpoint source pollution. This study proposed an approach that can effectively evaluate strategies for water management in a creek watershed with sparse data.


Assuntos
Monitoramento Ambiental , Nitrogênio/análise , China , Rios , Poluição da Água/análise , Qualidade da Água
18.
ACS Appl Mater Interfaces ; 12(31): 34505-34513, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32508084

RESUMO

Cancer residues around the surgical site remain a significant cause of treatment failure with cancer recurrence. To prevent cancer recurrence and simultaneously repair surgery-caused defects, it is urgent to develop implantable biomaterials with anticancer ability and good biological activity. In this work, a functionalized implant is successfully fabricated by doping the effective anticancer element selenium (Se) into the potassium-sodium niobate piezoceramic, which realizes the wireless combination of electrotherapy and chemotherapy. Herein, we demonstrate that the Se-doped piezoelectric implant can cause mitochondrial damage by increasing intracellular reactive oxygen species levels and then trigger the caspase-3 pathway to significantly promote apoptosis of osteosarcoma cells in vitro. Meanwhile, its good biocompatibility has been verified. These results are of great importance for future deployment of wireless electro- and chemostimulation to modulate biological process around the defective tissue.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Técnicas Eletroquímicas , Selênio/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Ratos , Selênio/química , Comprimidos/síntese química , Comprimidos/química , Comprimidos/farmacologia
19.
Huan Jing Ke Xue ; 40(12): 5340-5347, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854605

RESUMO

In-situ monitoring, geographic information technology (GIS), watershed model, and statistical techniques were coupled in this study to explore the responses of riverine phosphorus exports to land use pattern and hydrological regime in the Jiulong River Watershed (JRW). We analyzed riverine phosphorus concentrations and exports from March 2015 to February 2017 across a land use gradient spanning 14 monitored sampling sites. Results showed that significantly spatial and seasonal variations of phosphorus concentrations and exports were observed in JRW. Mean phosphorus concentrations and exports were the highest in the agricultural watershed, followed by the urban watershed, whereas the West River reach had higher mean phosphorus concentration and export than the North River reach. Mean concentrations of phosphorus were higher in spring and winter, whereas lower concentrations were observed in autumn and summer. Phosphorus exports were higher in spring and summer, consistent with the seasonal trend of runoff. Phosphorus concentrations and exports had negative correlations with percentages of forest and bare land, and were positively correlated with cropland and orchard. The responses of riverine phosphorus to land use types and hydrological regime varied across seasons, whereas the relationships between phosphorus concentrations/exports and land use or runoff were the strongest in summer, suggesting that non-point source pollution associated with agricultural activities would be the critical source of riverine phosphorus and an increase in forest percentage could be useful for improving water quality. Overall, the spatiotemporal patterns of phosphorus exports were affected by land use pattern, as well as the characteristics of the hydrological regime.

20.
Biopolymers ; 110(12): e23328, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31454076

RESUMO

Blood vessels play an important role in bone defect repair and growth, and a critical challenge of bone defect repair is the promotion of blood vessel formation. Most of the current methods promote vascularization by adding specific growth factors, which are costly and easy to inactivate. In this study, we developed a covalently cross-linked aminated bioactive glass nanoparticle-chondroitin sulfate methacrylate (ABGN-CSMA) organic-inorganic composite hydrogel with angiogenic properties. The amino groups of the ABGNs form covalent bonds with the carboxyl groups on CSMA. Surface amination modification of BGNs not only improved the dispersion of BGNs in CSMA but also significantly improved the mechanical properties of the composite hydrogel. The largest storage modulus (1200 Pa), the largest loss modulus (560 Pa) and the strongest resistance to deformation of the hydrogel are seen at 10% concentration of ABGNs. Simultaneously, the local pH stability and sustained ion release of the composite hydrogel are conducive to cell adhesion, proliferation, and angiogenesis. This work provides evidence for the development of covalently cross-linked organic-inorganic composite hydrogels with angiogenic properties.


Assuntos
Sulfatos de Condroitina , Materiais Revestidos Biocompatíveis , Células Endoteliais da Veia Umbilical Humana/metabolismo , Hidrogéis , Nanopartículas/química , Neovascularização Fisiológica/efeitos dos fármacos , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Vidro , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Metacrilatos/química , Metacrilatos/farmacologia , Propriedades de Superfície
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