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1.
J Prosthet Dent ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38991886

RESUMO

STATEMENT OF PROBLEM: Conventional impression techniques for complete arch implant-supported fixed dental prostheses (CIFDPs) are technique sensitive. Stereophotogrammetry (SPG) and intraoral scanning (IOS) may offer alternatives to conventional impression making. PURPOSE: The purpose of this in vitro study was to assess the accuracy and passive fit of IOS with prefabricated aids, SPG, and open tray impression (OI) for CIFDPs with different implant distributions. MATERIAL AND METHODS: Three definitive casts with 4 parallel implants (4-PARA), 4 inclined implants (4-INCL), and 6 parallel implants (6-PARA) were fabricated. Three recording techniques were tested: IOS with prefabricated aids, SPG, and OI. The best and the worst scans were selected to fabricate 18 milled aluminum alloy frameworks. The trueness and precision of distance deviation (∆td and ∆pd), angular deviation (∆tθand ∆pθ), root mean square errors (∆tRMS for ∆pRMS), and passive fit score of frameworks were recorded. Two-way ANOVA was applied. RESULTS: SPG showed the best trueness and precision (95%CI of ∆td/∆tθ/∆tRMS, 31 to 39 µm, 0.22 to 0.28 degrees, 20 to 23 µm; 95%CI of ∆pd/∆pθ/∆pRMS, 9 to 11 µm, 0.06 to 0.08 degrees, 8 to 10 µm), followed by OI (61 to 83 µm, 0.33 to 0.48 degrees, 28 to 48 µm; 66 to 81 µm, 0.29 to 0.38 degrees, 32 to 41 µm) and IOS (143 to 193 µm, 0.37 to 0.50 degrees, 81 to 96 µm; 89 to 111 µm, 0.27 to 0.31 degrees, 51 to 62 µm). Tilted implants were associated with increased distance deviation. Increased implant number was associated with improved recording precision. The passive fit of frameworks was negatively correlated with the RMS error, and the correlation coefficient was -0.65 (P=.003). CONCLUSIONS: SPG had the best accuracy. Implant distributions affected implant precision. The RMS error can be used to evaluate the passive fit of frameworks.

2.
Artigo em Inglês | MEDLINE | ID: mdl-37746813

RESUMO

OBJECTIVES: The aim of this clinical study was to compare the accuracy of intraoral scan system (IOS) with prefabricated aids and stereophotogrammetry (SPG) compared with open tray implant impression (OI) for complete-arch implant-supported fixed dental prostheses (CIFDP). MATERIALS AND METHODS: Patients needing CIFDP were enrolled in this study. OI, reference standard, IOS with prefabricated aids, and SPG were performed for each patient. Distance and angle deviations between all pairs of abutment analogs, root mean square (RMS) errors between the aligned test and reference model, and chairside time were measured. The effect of inter-abutment distance, jaw (maxilla or mandible), number of implants, and arch length on deviations was analyzed. The mixed effect model was applied to analyze deviations and RMS errors. RESULTS: Fifteen consecutive individuals (6 females and 9 males, 47-77 years old) with 22 arches (9 upper and 13 lower jaws) and 115 implants were included. There was no significant difference in distance deviation comparing SPG and IOS with OI (p > .05). IOS showed a significantly greater angle deviation and RMS errors than SPG (median 0.40° vs. 0.31°, 69 µm vs. 45 µm, p < .01). The inter-abutment distance was negatively correlated with the accuracy of SPG and IOS (p < .05). The chairside time for IOS, SPG, and OI was 10.49 ± 3.50, 14.71 ± 2.86, and 20.20 ± 3.01 min, respectively (p < .01). CONCLUSIONS: The accuracy of SPG and IOS with prefabricated aids was comparable. IOS was the most efficient workflow.

3.
Ecotoxicol Environ Saf ; 251: 114521, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36641864

RESUMO

Microplastics (MPs) has shown adsorption of hydrophilic organic matters (HOMs) in aqueous environments. However, it is still difficult to predict the adsorption behaviors of HOMs by different MPs, especially in authentic water systems. In this study, the adsorption behaviors and mechanisms of norfloxacin (NOR) onto polyamide (PA) MPs were investigated in both simulated and real surface water. The results showed that the adsorption equilibrium of NOR by PA in simulated surface water could be achieved within 15 h, while the adsorption rate of NOR in real surface was slowed down, with the equilibrium time of 25 h. Pseudo-second-order model could well describe the adsorption kinetics data. The experimental maximum adsorption capacity of NOR on PA in real surface water (e. g. 132.54 ug/g) was dramatically reduced by 37.5 % compared with that in simulated surface water (e. g. 212.25 ug/g), and the adsorption isotherm would obey Freundlich model. Besides, the leaching of NOR from the surface of PA could occur obviously at acidic environment. Furthermore, the salinity and natural organic matter exhibited significantly adverse effects on the NOR adsorption. Finally, the results of 2D Fourier transform infrared correlation spectroscopy and X-ray photoelectron spectroscopy indicated that the electrostatic, H-bond and van der Waals interactions were involved in the adsorption. More importantly, the sequential functional groups in the adsorption process followed the orders: 1638 (CO) > 1542 amide II (-NH-CO) > 717 (CH2) > 1445 (CO) > 973 amide IV (CONH). This study could provide an insight into the interactions between PA and NOR in different water environments.


Assuntos
Poluentes Químicos da Água , Água , Microplásticos , Norfloxacino , Plásticos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia Fotoeletrônica , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Nylons , Adsorção , Cinética
4.
Dent Traumatol ; 38(5): 367-373, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35605156

RESUMO

BACKGROUND/AIMS: Pediatric oral and maxillofacial surgeons have faced severe challenges in ward management due to their high risk of exposure during the COVID-19 epidemic. The aim of this study was to analyze and summarize the treatment methods and infection prevention and control measures applied in emergency cases in the Department of Pediatric Oral and Maxillofacial Surgery, Children's Hospital of Chongqing Medical University, during the COVID-19 epidemic. METHODS: In this retrospective study, information was collected from 256 pediatric emergency patients who were treated from January 23, 2020 to August 9, 2021. The patients' data were statistically analyzed according to age, gender, disease and pathogenesis, operation time, and the main treatment applied in pediatric oral and maxillofacial emergency cases during the COVID-19 epidemic. RESULTS: During the epidemic period, 256 pediatric emergency patients were successfully treated. Among them, there were 170 boys and 86 girls. In all, 182 patients were diagnosed with oral or facial lacerations; 43 had jaw fractures; 26 had maxillofacial infections; and five had dento-alveolar fractures. A total of 246 patients underwent surgery under negative pressure with level 3 protection standards. No doctors or patients infected with COVID-19 were found throughout the stury period. CONCLUSIONS: Pediatric oral and maxillofacial emergency in-patients mainly experienced maxillofacial trauma during the COVID-19 epidemic, followed by infection. Effective diagnosis and treatment, and avoidance of COVID-19 infection can be achieved by strictly following epidemic prevention and treatment procedures.


Assuntos
COVID-19 , Traumatismos Maxilofaciais , Fraturas Cranianas , Criança , Surtos de Doenças , Feminino , Humanos , Masculino , Traumatismos Maxilofaciais/epidemiologia , Traumatismos Maxilofaciais/terapia , Estudos Retrospectivos , Fraturas Cranianas/epidemiologia
5.
J Esthet Restor Dent ; 32(3): 265-271, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32064786

RESUMO

OBJECTIVE: To describe a method to fabricate donor tooth replica to assist surgeons in preparation of recipient socket during tooth autotransplantation. MATERIALS AND METHODS: A total of 28 compromised molars in 27 patients were transplanted with third molars using computer-aided rapid prototyping (CARP) technique. Surgery time and extra-alveolar time were documented. Postoperatively, the distance between cervix of transplanted tooth and the alveolar wall was measured. The degree of postoperative pain experienced was assessed with visual analog scale at day 1, 3, and 7. RESULTS: From 28 clinical cases, the average extra-alveolar time and surgery time were 2.5 minutes (±1.3) and 44 minutes (±6.8), respectively. Postoperatively, the average distance between cervix of transplanted tooth and the alveolar wall was 0.87 mm (±0.15) at the mesial-cervix, 0.95 mm (±0.17) at the distal-cervix, 0.88 mm (±0.18) at the buccal-cervix, and 0.95 mm (±0.13) at the lingual-cervix. The value of visual analog scale score significantly decreased from day 1 to day 3. CONCLUSIONS: CARP is a reliable technique for fabrication of tooth like surgical replicas in conventional autotransplantation. CLINICAL SIGNIFICANCE: CARP technique minimized extra-oral time, reduced iatrogenic damage, and consequently increased the survival rate of tooth autotransplantation.


Assuntos
Cirurgia Assistida por Computador , Dente , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Dente Molar , Dente Serotino , Transplante Autólogo
6.
Small ; 15(16): e1900691, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30913380

RESUMO

Activatable imaging probes are promising to achieve increased signal-to-noise ratio for accurate tumor diagnosis and treatment monitoring. Magnetic resonance imaging (MRI) is a noninvasive imaging technique with excellent anatomic spatial resolution and unlimited tissue penetration depth. However, most of the activatable MRI contrast agents suffer from metal ion-associated potential long-term toxicity, which may limit their bioapplications and clinical translation. Herein, an activatable MRI agent with efficient MRI performance and high safety is developed for drug (doxorubicin) loading and tumor signal amplification. The agent is based on pH-responsive polymer and gadolinium metallofullerene (GMF). This GMF-based contrast agent shows high relaxivity and low risk of gadolinium ion release. At physiological pH, both GMF and drug molecules are encapsulated into the hydrophobic core of nanoparticles formed by the pH-responsive polymer and shielded from the aqueous environment, resulting in relatively low longitudinal relativity and slow drug release. However, in acidic tumor microenvironment, the hydrophobic-to-hydrophilic conversion of the pH-responsive polymer leads to amplified MR signal and rapid drug release simultaneously. These results suggest that the prepared activatable MRI contrast agent holds great promise for tumor detection and monitoring of drug release.


Assuntos
Portadores de Fármacos , Fulerenos/química , Gadolínio/química , Imageamento por Ressonância Magnética , Animais , Meios de Contraste/química , Preparações de Ação Retardada/uso terapêutico , Doxorrubicina/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Polímeros/química , Microambiente Tumoral
7.
J Mater Sci Mater Med ; 29(5): 66, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29744595

RESUMO

Anticoagulation therapy plays a vital role in the prevention of blood clot formation during hemodialysis and hemofiltration, especially for critical care patients. Here, we synthesized a novel argatroban (Arg)-modified polysulfone (PSf) membrane for anticoagulation. Arg was grafted onto the PSF membrane via chemical modification to increase membrane hydrophilicity. Protein adsorption, coagulation, as well as activation of platelets and complement systems were greatly reduced on the Arg-modified PSf membrane. Thus, the recalcification time and the activated partial thrombin time (APTT) were increased after the modification. In comparison with the pristine PSf membrane, the Arg-modified PSf membrane showed better hemocompatibility and anticoagulation properties, indicating its potential for applications in hemodialysis and hemofiltration. Modification of the PSf membrane has been investigated in attempts to further enhance the anticoagulation properties of the hemodialysis membranes, including a heparin-modified PSf membrane. However, heparin can inhibit plasma-free thrombin, and cause the occurrence of heparin-induced thrombocytopenia (HIT), which increases the risk of bleeding during dialysis in critical care patients. To address this problem, we modified PSf membrane with as a novel direct thrombin inhibitors, argatroban (Arg). It can reversibly bind to thrombin, inhibiting not only the plasma-free thrombin in the blood, but also clot-bound thrombin.


Assuntos
Anticoagulantes/síntese química , Membranas Artificiais , Ácidos Pipecólicos/química , Polímeros/química , Diálise Renal/instrumentação , Sulfonas/química , Trombose/prevenção & controle , Adsorção , Adulto , Anticoagulantes/química , Arginina/análogos & derivados , Coagulação Sanguínea/efeitos dos fármacos , Testes de Coagulação Sanguínea , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Teste de Materiais , Adesividade Plaquetária/efeitos dos fármacos , Sulfonamidas
8.
Metab Eng ; 23: 78-91, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24566041

RESUMO

Genetic engineering of Halomonas spp. was seldom reported due to the difficulty of genetic manipulation and lack of molecular biology tools. Halomonas TD01 can grow in a continuous and unsterile process without other microbial contaminations. It can be therefore exploited for economic production of chemicals. Here, Halomonas TD01 was metabolically engineered using the gene knockout procedure based on markerless gene replacement stimulated by double-strand breaks in the chromosome. When gene encoding 2-methylcitrate synthase in Halomonas TD01 was deleted, the conversion efficiency of propionic acid to 3-hydroxyvalerate (3HV) monomer fraction in random PHBV copolymers of 3-hydroxybutyrate (3HB) and 3HV was increased from around 10% to almost 100%, as a result, cells were grown to accumulate 70% PHBV in dry weight (CDW) consisting of 12mol% 3HV from 0.5g/L propionic acid in glucose mineral medium. Furthermore, successful deletions on three PHA depolymerases eliminate the possible influence of PHA depolymerases on PHA degradation in the complicated industrial fermentation process even though significant enhanced PHA content was not observed. In two 500L pilot-scale fermentor studies lasting 70h, the above engineered Halomonas TD01 grew to 112g/L CDW containing 70wt% P3HB, and to 80g/L CDW with 70wt% P(3HB-co-8mol% 3HV) in the presence of propionic acid. The cells grown in shake flasks even accumulated close to 92% PHB in CDW with a significant increase of glucose to PHB conversion efficiency from around 30% to 42% after 48h cultivation when pyridine nucleotide transhydrogenase was overexpressed. Halomonas TD01 was also engineered for producing a PHA regulatory protein PhaR which is a robust biosurfactant.


Assuntos
Halomonas , Engenharia Metabólica/métodos , Poliésteres/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Técnicas de Silenciamento de Genes , Halomonas/genética , Halomonas/metabolismo
9.
Macromol Biosci ; 24(6): e2300496, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38359399

RESUMO

The contact between the dialysis membrane and blood can induce oxidative stress and thrombosis, causing oxidative organ damage and impaired toxin clearance. To date, the selection of anticoagulants has focused on mechanisms inhibiting white, but not red (erythrocytes) thrombus formation. In the present study, polyethersulfone (PES) membranes are modified with the antioxidant drug tiopronin; the physicochemical properties and dialysis performance of the Tio-PES membranes are evaluated. The effects on erythrocyte thrombosis are evaluated in terms of erythrocyte morphology, prothrombotic properties (adhesion, aggregation, viscosity, sedimentation, and hemolysis), and fibrinogen (FIB)-erythrocyte interactions. The regular anticoagulant and antiplatelet properties are also assessed. Superoxide dismutase, malondialdehyde, plasma protein, and complement C3a are further determined. Finally, the biosafety of the Tio-PES membranes is evaluated both in vitro and in vivo. The Tio-PES membranes exhibit excellent physicochemical properties and improved dialysis performance. It is found that the Tio-PES membranes stabilize erythrocyte morphology, reduce erythrocyte prothrombotic properties, decrease FIB adsorption, and prevent red thrombus formation. In addition, the Tio-PES membranes exhibit excellent antioxidant properties and show biosafety in primary toxicity studies. Thus, Tio-PES membranes hold promise as novel, safe, and effective dialysis materials for potential clinical application.


Assuntos
Antioxidantes , Eritrócitos , Teste de Materiais , Membranas Artificiais , Polímeros , Sulfonas , Trombose , Sulfonas/química , Sulfonas/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Polímeros/química , Polímeros/farmacologia , Trombose/prevenção & controle , Humanos , Animais , Hemólise/efeitos dos fármacos , Anticoagulantes/farmacologia , Anticoagulantes/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Fibrinogênio/química , Fibrinogênio/metabolismo
10.
Mil Med Res ; 11(1): 13, 2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38369464

RESUMO

Scar formation resulting from burns or severe trauma can significantly compromise the structural integrity of skin and lead to permanent loss of skin appendages, ultimately impairing its normal physiological function. Accumulating evidence underscores the potential of targeted modulation of mechanical cues to enhance skin regeneration, promoting scarless repair by influencing the extracellular microenvironment and driving the phenotypic transitions. The field of skin repair and skin appendage regeneration has witnessed remarkable advancements in the utilization of biomaterials with distinct physical properties. However, a comprehensive understanding of the underlying mechanisms remains somewhat elusive, limiting the broader application of these innovations. In this review, we present two promising biomaterial-based mechanical approaches aimed at bolstering the regenerative capacity of compromised skin. The first approach involves leveraging biomaterials with specific biophysical properties to create an optimal scarless environment that supports cellular activities essential for regeneration. The second approach centers on harnessing mechanical forces exerted by biomaterials to enhance cellular plasticity, facilitating efficient cellular reprogramming and, consequently, promoting the regeneration of skin appendages. In summary, the manipulation of mechanical cues using biomaterial-based strategies holds significant promise as a supplementary approach for achieving scarless wound healing, coupled with the restoration of multiple skin appendage functions.


Assuntos
Materiais Biocompatíveis , Cicatrização , Humanos , Cicatrização/fisiologia , Materiais Biocompatíveis/uso terapêutico , Materiais Biocompatíveis/química , Pele/lesões , Cicatriz/patologia
11.
ACS Appl Bio Mater ; 7(5): 3154-3163, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38695332

RESUMO

ß-Galactosidase (ß-Gala) is an essential biomarker enzyme for early detection of breast tumors and cellular senescence. Creating an accurate way to monitor ß-Gala activity is critical for biological research and early cancer detection. This work used fluorometric, colorimetric, and paper-based color sensing approaches to determine ß-Gala activity effectively. Via the sensing performance, the catalytic activity of ß-Gala resulted in silicon nanoparticles (SiNPs), fluorescent indicators obtained via a one-pot hydrothermal process. As a standard enzymatic hydrolysis product of the substrate, kaempferol 3-O-ß-d-galactopyranoside (KOßDG) caused the fluorometric signal to be attenuated on kaempferol-silicon nanoparticles (K-SiNPs). The sensing methods demonstrated a satisfactory linear response in sensing ß-Gala and a low detection limit. The findings showed the low limit of detection (LOD) as 0.00057 and 0.098 U/mL for fluorometric and colorimetric, respectively. The designed probe was then used to evaluate the catalytic activity of ß-Gala in yogurt and human serum, with recoveries ranging from 98.33 to 107.9%. The designed sensing approach was also applied to biological sample analysis. In contrast, breast cancer cells (MCF-7) were used as a model to test the in vitro toxicity and molecular fluorescence imaging potential of K-SiNPs. Hence, our fluorescent K-SiNPs can be used in the clinic to diagnose breast cellular carcinoma, since they can accurately measure the presence of invasive ductal carcinoma in serologic tests.


Assuntos
Neoplasias da Mama , Quempferóis , Nanopartículas , Silício , beta-Galactosidase , Feminino , Humanos , beta-Galactosidase/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/síntese química , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Colorimetria , Quempferóis/química , Quempferóis/farmacologia , Células MCF-7 , Estrutura Molecular , Nanopartículas/química , Tamanho da Partícula , Silício/química
12.
Arch Med Sci ; 20(2): 506-516, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38757038

RESUMO

Primary Sjögren's syndrome (pSS) is a chronic, systemic autoimmune disease characterized by dryness of the eyes and mouth. The histological feature is mononuclear cell infiltration in exocrine glands, primarily salivary and lachrymal glands. As the disease progresses, some other tissues and organs may be involved and extraglandular manifestations ensue. The major current treatments are palliative and empirical, and in most cases the outcomes are not satisfactory. Emerging data indicate a critical role of lymphocytes in its development and progression. While pioneering work targeting B cells has demonstrated some encouraging results, more trials are warranted to validate the safety and efficacy. In addition, modulation of T cell function with abatacept ameliorates the severity of pSS. Furthermore, clinical trials to inhibit important cytokines involved in its formation have been carried out. In this article, we summarize and compare current biological therapies in order to find new and effective treatments for pSS.

13.
Biol Trace Elem Res ; 202(5): 2100-2110, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37582921

RESUMO

The underlying mechanism of fluorosis has not been fully elucidated. The purpose of this study was to explore the mechanism of fluorosis induced by sodium fluoride (NaF) using proteomics. Six offspring rats exposed to fluoride without dental fluorosis were defined as group A, 8 offspring rats without fluoride exposure were defined as control group B, and 6 offspring rats exposed to fluoride with dental fluorosis were defined as group C. Total proteins from the peripheral blood were extracted and then separated using liquid chromatography-tandem mass spectrometry. The identified criteria for differentially expressed proteins were fold change > 1.2 or < 0.83 and P < 0.05. Gene Ontology function annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed using the oeCloud tool. The 177 upregulated and 22 downregulated proteins were identified in the A + C vs. B group. KEGG pathway enrichment analysis revealed that transforming growth factor-ß (TGF-ß) signaling pathway significantly enriched. PPI network constructed using Cytoscape confirmed RhoA may play a crucial role. The KEGG results of genes associated with fluoride and genes associated with both fluoride and inflammation in the GeneCards database also showed that TGF-ß signaling pathway was significantly enriched. The immunofluorescence in HPA database showed that the main expression sites of RhoA are plasma membrane and cytosol, while the main expression site of Fbn1 is the Golgi apparatus. In conclusion, long-term NaF intake may cause inflammatory response in the peripheral blood of rats by upregulating TGF-ß signaling pathway, in which RhoA may play a key role.


Assuntos
Intoxicação por Flúor , Fluorose Dentária , Ratos , Animais , Fluoretos/toxicidade , Proteômica/métodos , Fluoreto de Sódio/toxicidade , Biomarcadores , Transdução de Sinais , Fator de Crescimento Transformador beta/genética
14.
Sci Total Environ ; 861: 161090, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36586767

RESUMO

This study investigated poplar pretreatments by chemi-mechanical pulping (CMP) under different beating degrees and alkali concentrations. The enzyme-mediated hydrolysis of pretreated poplar was enhanced by deacetylation and delignification. Meanwhile, the remaining lignin residues were used to produce lignin/polyacrylonitrile (PAN) fiber mats by electrospinning. These mats exhibited excellent mechanical and UV-blocking performance when the lignin was obtained from pulps under milder alkali concentrations (5 g/L). 31P nuclear magnetic resonance (31P NMR) and two-dimensional heteronuclear single-quantum correlation nuclear magnetic resonance (2D HSQC NMR) data revealed that increasing the beating degree at low alkali concentration during the CMP process led to the cleavage of ß-O-4' interunit linkages and re-condensation in lignin, releasing several phenolic groups. Lignin with more linear ß-O-4' interunit linkages and lesser phenolic groups, obtained from treatment of CMP with lower alkali concentration (5 g/L) and beating degree (20°SR), resulted in the corresponding lignin/PAN fiber mats exhibiting better mechanical performance. Further, lignin, along with the increased phenolic-OH and COOH, and p-hydroxybenzoate (PB) units with a more extended conjugate structure, derived from CMP under lower alkali concentration (5 g/L) and higher beating degree (45°SR), led to a stronger ultraviolet (UV) absorption in the corresponding lignin/PAN mats. To summarize, this study reports a mild and low-pollution biomass pretreatment method (CMP) that can efficiently regulate the lignin structure and exhibit efficient anti-ultraviolet properties. The corresponding UV-blocking fiber mats can be potentially used as materials for wearable fabrics.


Assuntos
Lignina , Populus , Lignina/química , Açúcares , Resinas Acrílicas , Hidrólise , Populus/química , Álcalis
15.
Biomed Mater ; 19(1)2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-37972551

RESUMO

A multifunctional hydrogel dressing with hemostatic, antibacterial, and reactive oxygen species (ROS)-removing properties is highly desirable for the clinical treatment of open wounds. Although many wound dressings have been prepared, the modification of polymers is often involved in the preparation process, and the uncertainty of biological safety and stability of modified polymers hinders the clinical application of products. In this study, inspired by the composition and crosslinking pattern of extracellular matrix (ECM), a deeply ECM-mimicking multifunctional hydrogel dressing is created. Tannic acid (TA) and poly-ϵ-lysine (EPL) are added into a gelatin/hyaluronic acid (Gel/HA) matrix, and a stable hydrogel is formed due to the formation of the triple helix bundles of gelatin and hydrogen bonds between polymers. The introduction of TA and EPL endows the ECM-mimicking hydrogel with stable rheological properties, as well as antibacterial and hemostatic functions. The as-produced hydrogels have suitable swelling ratio, enzyme degradability, and good biocompatibility. In addition, it also shows a significant ability to eliminate ROS, which is confirmed by the elimination of 2,2-diphenyl-1-picrylhydrazyl free radical. Full-thickness skin wound repair experiment and histological analysis of the healing site in mice demonstrate that the developed ECM-mimicking Gel/HA hydrogels have a prominent effect on ECM formation and promotion of wound closure. Taken together, these findings suggest that the multifunctional hydrogels deeply mimicking the ECM are promising candidates for the clinical treatment of open wounds.


Assuntos
Gelatina , Hemostáticos , Animais , Camundongos , Hidrogéis , Ácido Hialurônico , Espécies Reativas de Oxigênio , Antibacterianos , Matriz Extracelular , Lisina , Polímeros , Cicatrização
16.
Drug Deliv ; 30(1): 2241664, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37545034

RESUMO

Gradual loss of neuronal structure and function due to impaired blood-brain barrier (BBB) and neuroinflammation are important factors in multiple sclerosis (MS) progression. Our previous studies demonstrated that the C16 peptide and angiopoietin 1 (Ang-1) compound (C + A) could modulate inflammation and vascular protection in many models of MS. In this study, nanotechnology and a novel nanovector of the leukocyte chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (fMLP) were used to examine the effects of C + A on MS. The acute experimental autoimmune encephalomyelitis (EAE) model of MS was established in Lewis rats. The C + A compounds were conjugated to control nano-carriers and fMLP-nano-carriers and administered to animals by intravenous injection. The neuropathological changes in the brain cortex and spinal cord were examined using multiple approaches. The stimulation of vascular injection sites was examined using rabbits. The results showed that all C + A compounds (C + A alone, nano-carrier C + A, and fMLP-nano-carrier C + A) reduced neuronal inflammation, axonal demyelination, gliosis, neuronal apoptosis, vascular leakage, and BBB impairment induced by EAE. In addition, the C + A compounds had minimal side effects on liver and kidney functions. Furthermore, the fMLP-nano-carrier C + A compound had better effects compared to C + A alone and the nano-carrier C + A. This study indicated that the fMLP-nano-carrier C + A could attenuate inflammation-related pathological changes in EAE and may be a potential therapeutic strategy for the treatment of MS and EAE.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Ratos , Animais , Coelhos , N-Formilmetionina Leucil-Fenilalanina/química , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Esclerose Múltipla/tratamento farmacológico , Lipossomos , Angiopoietina-1/uso terapêutico , Ratos Endogâmicos Lew , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/patologia , Inflamação/tratamento farmacológico
17.
Biomater Adv ; 139: 213012, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35882156

RESUMO

Blood purification therapy is widely used in the treatment of critically ill patients. However, most dialysis membranes are prone to thrombosis. Activated coagulation factor X (FXa) functions at the intersection of intrinsic, extrinsic, and common coagulation pathways and plays a central role in thrombogenesis. To date, few dialysis membranes that directly inhibit FXa have been reported. We modified a polyethersulfone(PES) membrane using apixaban as an FXa inhibitor and investigated the performance of this membrane (AMPES). The contact angle of the modified membrane was reduced. PWF and retention rates of BSA were increased, demonstrating good hydrophilicity and dialysis performance. Albumin adsorption was reduced from 141.8 ± 15.5 to 114.1 ± 6.9 µg cm-2. Reduced protein adsorption, especially targeted anti-FXa effect, inhibited the activation of intrinsic, extrinsic, and common coagulation pathways, as evidenced by significant prolongations of activated partial thromboplastin time, prothrombin time, and thrombin time by 145.04, 46.84 and 11.46 s, respectively. Furthermore, we determined the FXa concentration of each group, and found that the modified membrane had better anticoagulant performance through the inhibition of FXa. Favorable antiplatelet activity was also demonstrated. Thromboelastogram was used to comprehensively evaluate the anticoagulant and antithrombotic activities of the modified membrane. The R value was increased by 43.1 min, while the reduction in α angle was 42.5°. The coagulation comprehensive index reduction was 34.3. In addition, C3a and C5a were decreased by 15.3 % and 30.4 %, respectively. Furthermore, in vitro cytotoxicity and erythrocyte stability testing as well as in vivo murine experiments demonstrated the biosafety of the modified membrane. These results indicate that the AMPES dialysis membrane has an excellent potential for clinical applications.


Assuntos
Inibidores do Fator Xa , Membranas Artificiais , Polímeros , Diálise Renal , Sulfonas , Trombose , Animais , Anticoagulantes/farmacologia , Antitrombina III , Fator Xa/metabolismo , Inibidores do Fator Xa/farmacologia , Fibrinolíticos/farmacologia , Humanos , Camundongos , Pirazóis , Piridonas , Diálise Renal/instrumentação , Trombose/tratamento farmacológico
18.
Trends Biotechnol ; 40(12): 1503-1518, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36270903

RESUMO

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.


Assuntos
Agricultura , Lignina , Sequestro de Carbono , Solo/química , Carbono , Fertilizantes
19.
Water Res ; 224: 119024, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36099764

RESUMO

The interaction between microplastics (MPs) and hydrophilic organic contaminants (HOCs) in natural water environment has recently raised great public attentions due to the potential toxicity to humans. However, the quantitative assessment is less studied. In this study, the interaction between ciprofloxacin (CIP) and ofloxacin (OFL) (two important HOCs) and virgin and aged polystyrene (PS) was investigated. The aged PS showed higher adsorption rate and capacity than the virgin PS, due to its larger surface area and more O-containing groups. The pH-dependent adsorption of CIP was higher than OFL on both virgin and aged PS; the maximum adsorption for both HOCs occurred at pH 5. The sequential orders of functional groups for the adsorption were discovered according to the study by the 2D correlation Fourier transform infrared spectroscopy. Several mechanisms existed for the interaction: (1) at 3.0 < pH < 5.0, the electrostatic attraction (EA) was inhibited while H-bond (HB) was dominant, accounting for > 60% of the total uptake; (2) at 5.0 < pH < 8.0, the contribution of EA increased to around 50-60% while HB decreased to 30-40%; (3) at 8.0 < pH < 10.0, EA, HB and π-π conjugation caused 30-40%, 25-40% and 20-45% of the total uptake, respectively; (4) at 10.0 < pH < 12.0, π-π conjugation accounted for 90-100%. Notably, higher adsorption of CIP was mainly attributed to the presence of secondary amino groups and its higher pKa value, correspondingly leading to the additional ordinary HB and negative charge-assisted HB, and EA interactions with PS. This study further provides clear evidences on the risk of MPs and HOCs on humans and aqueous living organisms.


Assuntos
Microplásticos , Poluentes Químicos da Água , Adsorção , Idoso , Ciprofloxacina/química , Humanos , Ofloxacino/química , Plásticos , Poliestirenos , Água/química , Poluentes Químicos da Água/análise
20.
Mater Sci Eng C Mater Biol Appl ; 135: 112659, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35577688

RESUMO

Blood purification therapy is widely used in patients with renal insufficiency and severe infections, where membrane-associated thrombosis is a side effect. How to improve the hemocompatibility of dialysis membranes and reduce thrombosis is a focus of current research, in which platelets play a key role. However, few dialysis membranes that directly inhibit platelets have been developed to date. In this study, a polyethersulfone (PES) membrane was modified with ticagrelor, a platelet P2Y12 receptor inhibitor, and detailed characterization was performed. The ticagrelor modified PES membrane (TMPES) showed good hydrophilicity and anti-protein adsorption and significantly inhibited platelet adhesion, aggregation, and activation, which demonstrated good antithrombotic properties. In addition, the membrane had excellent red blood cell (RBC) compatibility, anticoagulant, and antiinflammatory effects, which demonstrated superior biosafety in cell and animal experiments. Therefore, the TMPES dialysis membrane could have potential in clinical applications.


Assuntos
Membranas Artificiais , Trombose , Animais , Plaquetas/metabolismo , Humanos , Inibidores da Agregação Plaquetária/farmacologia , Polímeros , Diálise Renal , Sulfonas , Trombose/tratamento farmacológico , Ticagrelor
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