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1.
Ophthalmic Res ; 67(1): 85-95, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38109862

RESUMO

INTRODUCTION: The aims of the study were to investigate whether first-dose efficacy can predict third-dose anatomical response and analyze the risk factors for first-dose response of polypoidal choroidal vasculopathy (PCV) patients. METHODS: We retrospectively reviewed patients' medical records from 27 centers of China PCV Research Alliance. PCV patients treated with intravitreal injections of conbercept (IVC) based on the 3+ pro re nata regimen (three initial monthly injections, followed by injections as needed) with complete 3-month injection data were included. Response correlations, risk factor associations, changes in central macular thickness (CMT) or best-corrected visual acuity (BCVA), and number of injections in the first year of follow-up were evaluated separately in the pachy-PCV and non-pachy-PCV phenotypes. RESULTS: Overall, 165 eligible patients were included. There was a significant correlation between first-dose and third-dose anatomical response in pachy-PCV or non-pachy-PCV patients (rs = 0.611, p < 0.001; rs = 0.638, p < 0.001). Multivariate analysis revealed associations of good first-dose anatomical response in pachy-PCV patients with baseline CMT with a predicted area under the curve (AUC) of 0.847, while a good response in non-pachy-PCV patients was associated with baseline BCVA, baseline CMT, pigment epithelial detachment (PED) height, higher proportion of intraretinal fluid, and lower PED minimum diameter with a predicted AUC of 0.940. CMT in the good first-dose response group was significantly decreased from baseline at all first-year follow-up visits in both groups (p < 0.001), and mean BCVA was improved in the good versus poor first-dose anatomical response group (5.4 vs. 1.6 ETDRS letters in pachy-PCV, 10.6 vs. 7.4 letters in non-pachy-PCV) after the third injection. No significant difference was observed in the number of injections in the first year of follow-up between different response groups. CONCLUSION: In PCV patients receiving IVC, the first- and third-dose responses are significantly correlated, and different factors influence the first-dose response in different subtypes of PCV.


Assuntos
Resinas Acrílicas , Hidrazinas , Pólipos , Descolamento Retiniano , Humanos , Inibidores da Angiogênese/uso terapêutico , Vasculopatia Polipoidal da Coroide , Estudos Retrospectivos , Resultado do Tratamento , Descolamento Retiniano/etiologia , Fatores de Risco , Injeções Intravítreas , Tomografia de Coerência Óptica , Angiofluoresceinografia , Seguimentos , Pólipos/diagnóstico , Pólipos/tratamento farmacológico , Pólipos/complicações
2.
BMC Oral Health ; 24(1): 656, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38835024

RESUMO

INTRODUCTION: The efficacy of root canal treatment is greatly impacted by a thorough understanding of root canal anatomy. This systematic review and meta-analysis aim to thoroughly investigate the root morphology and canal configuration (RMCC) of permanent premolars (PMs). METHODOLOGY: A comprehensive analysis was conducted following the PRISMA guidelines. Literature exploration was carried out across four electronic databases (PubMed, Embase, Cochrane, and Web of Science). The risk of bias assessment was conducted for the included studies utilizing the Anatomical Quality Assessment (AQUA) tool. Data analysis was performed utilizing SPSS and RevMAN5.3.3. The meta-analysis was applied with a 95% confidence interval to calculate odds ratios (OR). RESULTS: Among the 82 selected studies, 59 studies exhibited potential bias in domain one (objective(s) and subject characteristics), followed by domain three (methodology characterization). The majority of maxillary PM1s had either single root (46.7%) or double roots (51.9%), while three-rooted variants were uncommon (1.4%). Conversely, most other PMs exhibited a single root. In terms of canal configuration, maxillary PM1s predominantly featured double distinct canals (87.2%), with the majority of maxillary PM2s displaying either a single canal (51.4%) or double canals (48.3%). Mandibular PMs were primarily characterized by single canals, accounting for 78.3% of mandibular PM1s and 90.3% of mandibular PM2s. Subgroup analyses revealed higher incidences of single-rooted and single-canalled PMs among Asians compared to Caucasians. Additionally, women exhibited a higher incidence of single-rooted PMs, while men showed a greater frequency of double-rooted PMs. CONCLUSIONS: The comprehensive analysis indicated that maxillary PM1s predominantly possess double roots and double canals, whereas maxillary PM2s and mandibular PMs were primarily characterized by single-rooted with a single canal. Notably, single root and single canal were more prevalent among women and Asian samples.


Assuntos
Dente Pré-Molar , Tomografia Computadorizada de Feixe Cônico , Cavidade Pulpar , Raiz Dentária , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Pré-Molar/diagnóstico por imagem , Dente Pré-Molar/anatomia & histologia , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/anatomia & histologia , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/anatomia & histologia
3.
Vascular ; 30(1): 52-62, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33568006

RESUMO

OBJECTIVES: Restenosis after stenting for superficial femoral artery atherosclerotic disease remains a significant clinical problem, especially for long-segment lesions. We assessed predictors of in-stent restenosis in patients with long-segment superficial femoral artery disease and hypothesized that pre-procedural ultrasound assessment would predict in-stent restenosis. METHODS: This single-center study retrospectively analyzed 283 limbs in 243 patients who treated with superficial femoral artery nitinol stent placement for long-segment (≥15 cm) lesions between 2015 and 2018. Color duplex ultrasound was performed pre-procedure and post-procedure at 3, 6, 12, 24, and 36 months. The endpoint was ≥50% in-stent restenosis in the superficial femoral artery. Primary patency rates were analyzed with Kaplan-Meier survival analysis and compared using the log-rank test. A multivariable Cox proportional hazards model was used to evaluate the risk factors for in-stent restenosis. RESULTS: The median length of lesions was 25.8 ± 8.1 cm. The cumulative freedom from ≥50% in-stent restenosis at 3, 6, 12, 24, and 36 months was 95.3%, 78.3%, 56.0%, 30.6%, and 15.9%, respectively. Univariate and multivariate Cox regression analysis showed that cumulative lesion length ≥ 25 cm (hazard ratio 1.681; p = 0.003), calcified plaque (hazard ratio 1.549, p = 0.006), poor runoff scores >10 (hazard ratio 1.870, p = 0.003), and chronic renal failure (hazard ratio 2.075, p = 0.009) were independent risk factors for in-stent restenosis. The agreement rate between ultrasound and angiography was 92.6% for cumulative lesion length (κ 0.851) and 91.9% for runoff score (κ 0.872). CONCLUSIONS: The results indicate that pre-procedural color duplex ultrasound evaluation is helpful for the selection of appropriate candidates for superficial femoral artery stent placement. Cumulative lesion length ≥25 cm, plaque calcification, poor distal runoff, and chronic renal failure independently predicted in-stent restenosis.


Assuntos
Artéria Femoral , Doença Arterial Periférica , Ligas , Artéria Femoral/diagnóstico por imagem , Humanos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Desenho de Prótese , Estudos Retrospectivos , Stents , Resultado do Tratamento , Grau de Desobstrução Vascular
4.
J Periodontal Res ; 54(2): 180-189, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30298589

RESUMO

BACKGROUND AND OBJECTIVE: Periodontal ligament-associated protein-1 (PLAP-1) is an important regulator of osteogenic differentiation of periodontal ligament cells and plays important role in the homeostasis of periodontal tissues. But the role of PLAP-1 in periodontitis is poorly understood. Expressions of PLAP-1 in experimental periodontitis are observed to elucidate whether PLAP-1 gets involved in the pathogenesis of periodontitis. MATERIAL AND METHODS: Wistar rats were randomly allocated to two groups (n = 6/group): Ligation group and Control group. PLAP-1 expression in experimental periodontitis was assessed by immunohistochemistry and collagen fibers in periodontal ligament were observed using picrosirius red staining. Expressions of PLAP-1 and CD68 in periodontitis were colocalized by double-labelled immunofluorescence. To further examine the relationship between PLAP-1 and osteoclastogenesis in experimental periodontitis, acute periodontal inflammatory infiltration and alveolar bone destruction were induced by administering ligated rats with 10 ng/mL tumor necrosis factor alpha (TNF-α; ligation + TNF-α group, n = 6). Alveolar bone loss was observed by micro-computed tomography (Micro-CT), and osteoclasts were identified by tartrate-resistant acid phosphatase staining (TRAP). Expressions of PLAP-1 in TNF-α stimulated human periodontal ligament cells were also detected at 24 and 48 hours by western blotting. RESULTS: PLAP-1 expression levels in periodontal ligament cells and collagen fibers were lower in the ligation group,compared with the control group. Similarly, TNF-α decreased PLAP-1 expression in human periodontal ligament cells in vitro. Degradation or destruction of collagen fibers accompanied the reduced PLAP-1 expression in the periodontal ligament in the ligation group. Colocalization of PLAP-1 and CD68 revealed the positive relationship between PLAP-1 and CD68+ infiltrating cells in periodontitis. More PLAP-1-positive inflammatory cells were found in the ligation + TNF-α group, compared with the ligation + saline group. CONCLUSION: PLAP-1-positive inflammatory cells are involved in the pathogenesis of periodontitis. An increase in PLAP-1-positive inflammatory cell number contributes periodontal inflammation and alveolar bone loss.


Assuntos
Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Periodontite/genética , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Modelos Animais de Doenças , Expressão Gênica , Humanos , Masculino , Osteogênese/genética , Ligamento Periodontal/citologia , Ligamento Periodontal/metabolismo , Ratos Wistar , Fator de Necrose Tumoral alfa
5.
Phys Chem Chem Phys ; 21(31): 17163-17169, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31342023

RESUMO

Two-dimensional (2D) heteromaterials with large interface contact and intimate interfacial charge transition have been considered to be an ideal model for constructing highly efficient photocatalysts. However, few studies have reported on these 2D heterojunctions. Herein, we report a series of new 2D heterojunctions comprising polyimide (PI) and perylene-3,4,9,10-tetracarboxylic dianhydride (TD). These heterojunctions, denoted as PI-TDx (where x represents the amount of TD added, i.e., x = 0.13, 0.18, 0.27, 0.54, and 1.08 g), were prepared by the solid thermal copolymerization of melamine (MA), pyromellitic dianhydride (PD), and different amounts of TD. FT-IR spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy analyses were used to verify the 2D heterojunction structure. Photocatalytic experiments reveal that PI-TDx exhibit excellent and stable photocatalytic performance for the degradation of the organic dyes rhodamine B (RhB) and methyl violet (MV), as well as for the photoreduction of Cr(vi), under visible-light irradiation. Among the samples, PI-TD0.18 exhibits the best photocatalytic performance. Its activity is about 2.7 times and 7.5 times higher than that of individual PIMP (formed by MA and PD) and PIMT (formed by MA and TD) for RhB degradation, respectively. Notably, PI-TD0.18 retains a certain photocatalytic activity under light irradiation at 600 nm. The photocatalytic-mechanism study demonstrates that PI-TD0.18 has a classic type-II heterojunction. Its 2D heterojunction greatly enhances the visible-light absorption of the composites and effectively suppresses the radiation recombination of photogenerated carriers, thereby improving its charge transfer and separation abilities and providing excellent photocatalytic performance. This work may serve as an important reference for the design and construction of new highly efficient 2D organic conjugated-polymer photocatalysts.


Assuntos
Poluentes Ambientais/química , Perileno/análogos & derivados , Perileno/química , Resinas Sintéticas/química , Catálise , Cromo/química , Corantes/química , Violeta Genciana/química , Luz , Oxirredução , Processos Fotoquímicos , Rodaminas/química , Propriedades de Superfície
6.
Exp Cell Res ; 371(1): 50-62, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30055135

RESUMO

DESI2 is a novel pro-apoptotic gene. We previously reported that DESI2 overexpression induces S phase arrest and apoptosis by activating checkpoint kinases. This work was to test whether the combination of endostatin, an endogenous antiangiogenic inhibitor, with DESI2 could improve the therapy efficacy in vitro and in vivo. The recombinant plasmid co-expressing DESI2 and endostatin was encapsulated with DOTAP/Cholesterol cationic liposome. Mice bearing CT26 colon carcinoma and LL2 lung cancer were treated with the DNA-liposome complex. We found that, in vitro, the combination of DESI2 and endostatin more efficiently inhibited proliferation of CT26, LL2, HCT116 and A549 cancer cells via apoptosis, as assessed by MTT assay, colony-formation assays, flow cytometric analysis, hoechst staining and activation of caspase-3, respectively. In addition, DESI2 overexpression caused up-regulation of RPS7, a substrate of DESI2 deubiquitination. Furthermore, siRNA targeting RPS7 partially abrogated, whereas RPS7 overexpression enhanced DESI2-induced inhibition of cell proliferation. Importantly, the combination also caused DNA lesions accumulation, which further promotes apoptosis. Mechanistic rationale suggested that endostatin first inhibits DNA-PKcs kinase, and partly abrogated DESI2-induced phosphorylation of DNA-PKcs, leading to increase of DNA damage, then contributes to DESI2-induced apoptosis. In vivo, the combined gene therapy more significantly inhibited tumor growth and efficiently prolonged the survival of tumor bearing mice than mono therapy. The improved antitumor effect was associated with inhibition of cell proliferation via apoptosis, as analyzed by TUNEL assay and PCNA immunostaining. The combination also inhibited angiogenesis, as assessed by alginate-encapsulated tumor cell assay and CD31 staining. Our data suggest that the combined gene therapy of DESI2 and endostatin can significantly enhance the antitumor activity as a DNA lesions accumulator, apoptosis inducer and angiogenesis inhibitor. The present study may provide a novel method for the treatment of cancer.


Assuntos
Carbono-Nitrogênio Liases/genética , Neoplasias do Colo/genética , Endostatinas/genética , Regulação Neoplásica da Expressão Gênica , Terapia Genética/métodos , Neoplasias Pulmonares/genética , Plasmídeos/metabolismo , Células A549 , Inibidores da Angiogênese/química , Inibidores da Angiogênese/metabolismo , Animais , Apoptose/genética , Carbono-Nitrogênio Liases/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Proliferação de Células , Colesterol/química , Colesterol/metabolismo , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Fragmentação do DNA , Endostatinas/metabolismo , Ácidos Graxos Monoinsaturados/química , Ácidos Graxos Monoinsaturados/metabolismo , Feminino , Células HCT116 , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Camundongos , Camundongos Endogâmicos C57BL , Plasmídeos/administração & dosagem , Plasmídeos/química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas Ribossômicas/antagonistas & inibidores , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Transdução de Sinais , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Molecules ; 24(17)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480234

RESUMO

This work presents the first example of utilization of amphiphilic block copolymer PCL-PEG-PCL as a stationary phase for capillary gas chromatographic (GC) separations. The PCL-PEG-PCL capillary column fabricated by static coating provides a high column efficiency of 3951 plates/m for n-dodecane at 120 °C. McReynolds constants and Abraham system constants were also determined in order to evaluate the polarity and possible molecular interactions of the PCL-PEG-PCL stationary phase. Its selectivity and resolving capability were investigated by using a complex mixture covering analytes of diverse types and positional, structural, and cis-/trans-isomers. Impressively, it exhibits high resolution performance for aliphatic and aromatic isomers with diverse polarity, including those critical isomers such as butanol, dichlorobenzene, dimethylnaphthalene, xylenol, dichlorobenzaldehyde, and toluidine. Moreover, it was applied for the determination of isomer impurities in real samples, suggesting its potential for practical use. The superior separation performance demonstrates the potential of PCL-PEG-PCL and related block copolymers as stationary phases in GC and other separation technologies.


Assuntos
Cromatografia Gasosa/métodos , Poliésteres/química , Polietilenoglicóis/química , Tensoativos/química , Varredura Diferencial de Calorimetria , Isomerismo , Temperatura , Termogravimetria
8.
Chemistry ; 20(23): 7116-21, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24753212

RESUMO

Hydroxyapatite (HAP), a well-known member of the calcium phosphate family, is the major inorganic component of bones and teeth in vertebrates. The highly ordered arrays of HAP structures are of great significance for hard tissue repair and for understanding the formation mechanisms of bones and teeth. However, the synthesis of highly ordered HAP structure arrays remains a great challenge. In this work, inspired by the ordered structure of tooth enamel, we have successfully synthesized three-dimensional bulk materials with large sizes (millimeter scale) that are made of highly ordered arrays of ultralong HAP microtubes (HOAUHMs) by solvothermal transformation of calcium oleate precursor. The core-shell-structured oblate sphere consists of a core that is composed of HAP nanorods and a shell that consists of highly ordered HAP microtube arrays. The prepared HOAUHMs are large: 6.0 mm in diameter and up to 1.4 mm in thickness. With increasing solvothermal reaction time, the HOAUHMs grow larger; the microtubes become more uniform and more ordered. This work provides a new synthetic method for synthesizing highly ordered arrays of uniform HAP ultralong microtubes that are promising for biomedical applications.


Assuntos
Cálcio/química , Durapatita/química , Ácido Oleico/química , Solventes/química , Microscopia Eletrônica de Varredura , Temperatura , Difração de Raios X
9.
J Mater Chem B ; 12(29): 7090-7102, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38984662

RESUMO

Magnetic resonance imaging (MRI) has emerged as a pivotal tool in contemporary medical diagnostics, offering non-invasive and high-resolution visualization of internal structures. Contrast agents are essential for enhancing MRI resolution, accurate lesion detection, and early pathology identification. While gadolinium-based contrast agents are widely used in clinics, safety concerns have prompted exploration of metal-free alternatives, including fluorine and nitroxide radical-based MRI contrast agents. Fluorine-containing compounds exhibit excellent MRI capabilities, with 19F MRI providing enhanced resolution and quantitative assessment. Nitroxide radicals, such as PROXYL and TEMPO, offer paramagnetic properties for MRI contrast. Despite their versatility, nitroxide radicals suffer from lower relaxivity values (r1) compared to gadolinium. Dual-modal imaging, combining 1H and 19F MRI, has gained prominence for its comprehensive insights into biological processes and disease states. However, existing dual-modal agents predominantly utilize gadolinium-organic ligands without incorporating nitroxide radicals. Here, we introduce a novel dual-modal MRI contrast agent (J-CA) featuring a Janus asymmetric nanostructure synthesized via seeded emulsion polymerization and post-modification. J-CA demonstrates excellent in vitro and in vivo performance in both 19F and 1H MRI, with a T2 relaxation time of 5 ms and an r1 value of 0.31 mM-1 s-1, ensuring dual-modal imaging capability. Moreover, J-CA exhibits superior biocompatibility and organ targeting, making it a promising candidate for precise lesion imaging and disease diagnosis. This work introduces a new avenue for metal-free dual-modal MRI, addressing safety concerns associated with traditional contrast agents.


Assuntos
Meios de Contraste , Imageamento por Ressonância Magnética , Nanoestruturas , Polímeros , Meios de Contraste/química , Meios de Contraste/síntese química , Imageamento por Ressonância Magnética/métodos , Animais , Camundongos , Nanoestruturas/química , Polímeros/química , Humanos , Flúor/química , Tamanho da Partícula
10.
Food Chem ; 453: 139673, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38772308

RESUMO

Herein, the nanolignin-containing cellulose nanofibrils (LCNF)-enabled ratiometric fluorescent bio-nanocomposite film is developed. Interestingly, the inclusion of LCNF in the cellulose-based film enhances the detecting performance of food freshness, such as high sensitivity to biogenic amines (BAs) (limit of detection (LOD) of up to 1.83 ppm) and ultrahigh discernible fluorescence color difference (ΔE = 113.11). The underlying mechanisms are the fluorescence resonance energy transfer (FRET), π - π interaction, and cation - π interaction between LCNF and fluorescein isothiocyanate (FITC), as well as the increased hydrophobicity due to lignin, which increases the interactions of amines with FITC. Its color stability (up to 28 days) and mechanical property (49.4 Mpa) are simultaneously improved. Furthermore, a smartphone based detecting platform is developed to achieve access to food safety. This work presents a novel technology, which can have a great potential in the field of food packaging and safety.


Assuntos
Celulose , Embalagem de Alimentos , Nanocompostos , Nanofibras , Celulose/química , Embalagem de Alimentos/instrumentação , Nanofibras/química , Nanocompostos/química , Transferência Ressonante de Energia de Fluorescência , Aminas Biogênicas/análise , Aminas Biogênicas/química , Fluorescência
11.
J Hazard Mater ; 470: 134195, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38581872

RESUMO

This study leveraged synthesis gas (syngas), a renewable resource attainable through the gasification of biowaste, to achieve efficient chromate removal from water. To enhance syngas transfer efficiency, a membrane biofilm reactor (MBfR) was employed. Long-term reactor operation showed a stable and high-level chromate removal efficiency > 95%, yielding harmless Cr(III) precipitates, as visualised by scanning electron microscopy and energy dispersive X-ray analysis. Corresponding to the short hydraulic retention time of 0.25 days, a high chromate removal rate of 80 µmol/L/d was attained. In addition to chromate reduction, in situ production of volatile fatty acids (VFAs) by gas fermentation was observed. Three sets of in situ batch tests and two groups of ex situ batch tests jointly unravelled the mechanisms, showing that biological chromate reduction was primarily driven by VFAs produced from in situ syngas fermentation, whereas hydrogen originally present in the syngas played a minor role. 16 S rRNA gene amplicon sequencing has confirmed the enrichment of syngas-fermenting bacteria (such as Sporomusa), who performed in situ gas fermentation leading to the synthesis of VFAs, and organics-utilising bacteria (such as Aquitalea), who utilised VFAs to drive chromate reduction. These findings, combined with batch assays, elucidate the pathways orchestrating synergistic interactions between fermentative microbial cohorts and chromate-reducing microorganisms. The findings facilitate the development of cost-effective strategies for groundwater and drinking water remediation and present an alternative application scenario for syngas.


Assuntos
Biofilmes , Reatores Biológicos , Cromatos , Membranas Artificiais , Cromatos/metabolismo , Fermentação , Poluentes Químicos da Água/metabolismo , Oxirredução , Ácidos Graxos Voláteis/metabolismo , Bactérias/metabolismo , Bactérias/genética , Hidrogênio/metabolismo , Gases/metabolismo , Biodegradação Ambiental
12.
Adv Healthc Mater ; 13(15): e2304158, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319101

RESUMO

The limited regulation strategies of the regeneration microenvironment significantly hinder bone defect repair effectiveness. One potential solution is using biomaterials capable of releasing bioactive ions and biomolecules. However, most existing biomaterials lack real-time control features, failing to meet high regulation requirements. Herein, a new Strontium (Sr) and epigallocatechin-3-gallate (EGCG) based metal-phenolic network with polydopamine (PMPNs) modification is prepared. This material reinforces a biomimetic scaffold made of extracellular matrix (ECM) and hydroxyapatite nanowires (nHAW). The PMPNs@ECM/nHAW scaffold demonstrates exceptional scavenging of free radicals and reactive oxygen species (ROS), promoting HUVECs cell migration and angiogenesis, inducing stem cell osteogenic differentiation, and displaying high biocompatibility. Additionally, the PMPNs exhibit excellent photothermal properties, further enhancing the scaffold's bioactivities. In vivo studies confirm that PMPNs@ECM/nHAW with near-infrared (NIR) stimulation significantly promotes angiogenesis and osteogenesis, effectively regulating the microenvironment and facilitating bone tissue repair. This research not only provides a biomimetic scaffold for bone regeneration but also introduces a novel strategy for designing advanced biomaterials. The combination of real-time photothermal intervention and long-term chemical intervention, achieved through the release of bioactive molecules/ions, represents a promising direction for future biomaterial development.


Assuntos
Regeneração Óssea , Catequina , Matriz Extracelular , Células Endoteliais da Veia Umbilical Humana , Indóis , Osteogênese , Alicerces Teciduais , Regeneração Óssea/efeitos dos fármacos , Humanos , Alicerces Teciduais/química , Matriz Extracelular/metabolismo , Matriz Extracelular/química , Células Endoteliais da Veia Umbilical Humana/metabolismo , Osteogênese/efeitos dos fármacos , Indóis/química , Indóis/farmacologia , Animais , Catequina/análogos & derivados , Catequina/química , Catequina/farmacologia , Polímeros/química , Durapatita/química , Durapatita/farmacologia , Estrôncio/química , Estrôncio/farmacologia , Nanofios/química , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/química , Diferenciação Celular/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Movimento Celular/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
13.
Chemistry ; 19(17): 5332-41, 2013 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-23460360

RESUMO

Hierarchically nanostructured porous hollow microspheres of hydroxyapatite (HAP) are a promising biomaterial, owing to their excellent biocompatibility and porous hollow structure. Traditionally, synthetic hydroxyapatite is prepared by using an inorganic phosphorus source. Herein, we report a new strategy for the rapid, sustainable synthesis of HAP hierarchically nanostructured porous hollow microspheres by using creatine phosphate disodium salt as an organic phosphorus source in aqueous solution through a microwave-assisted hydrothermal method. The as-obtained products are characterized by powder X-ray diffraction (XRD), Fourier-transform IR (FTIR) spectroscopy, SEM, TEM, Brunauer-Emmett-Teller (BET) nitrogen sorptometry, dynamic light scattering (DLS), and thermogravimetric analysis (TGA). SEM and TEM micrographs show that HAP hierarchically nanostructured porous hollow microspheres consist of HAP nanosheets or nanorods as the building blocks and DLS measurements show that the diameters of HAP hollow microspheres are within the range 0.8-1.5 µm. The specific surface area and average pore size of the HAP porous hollow microspheres are 87.3 m(2) g(-1) and 20.6 nm, respectively. The important role of creatine phosphate disodium salt and the influence of the experimental conditions on the products were systematically investigated. This method is facile, rapid, surfactant-free and environmentally friendly. The as-prepared HAP porous hollow microspheres show a relatively high drug-loading capacity and protein-adsorption ability, as well as sustained drug and protein release, by using ibuprofen as a model drug and hemoglobin (Hb) as a model protein, respectively. These experiments indicate that the as-prepared HAP porous hollow microspheres are promising for applications in biomedical fields, such as drug delivery and protein adsorption.


Assuntos
Materiais Biocompatíveis/síntese química , Durapatita/química , Nanoestruturas , Fosfocreatina/química , Adsorção , Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos/métodos , Hemoglobinas/análise , Ibuprofeno/análise , Microesferas , Micro-Ondas , Nanotubos , Nitrogênio , Fósforo/química , Porosidade , Difração de Raios X
14.
Medicine (Baltimore) ; 102(43): e35546, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37904471

RESUMO

The effectiveness of filtered air tamponade for superior retinal breaks was well established. This study was performed to compare the treatment efficacy of pars plana vitrectomies (PPV) with filtered air and silicone oil (SO) for patients with rhegmatogenous retinal detachment (RRD) caused by superior breaks with no or mild proliferative vitreoretinopathy. Patients of RRD with superior breaks who underwent PPV with filtered air (Group A) and SO (Group S) tamponade were reviewed retrospectively. Age, gender, laterality, lens status, duration of symptoms, macular status, proliferative vitreoretinopathy grade, use of perfluorocarbon liquid, early and late postoperative complications, follow-up duration were acquired. The primary anatomic reattachment after the first surgery and the final rate of successful reattachment was compared as the main outcome. Secondary outcomes were long-term postoperative best-corrected visual acuity (BCVA), rate of deferred cataract removal, surgical complications and total surgery number. The primary anatomic success rate was 88% (14/16 eyes) in Group A and 100% (16/16 eyes) in group S, which was not significantly different (P = .484). Both groups achieved 100% final anatomic success. The rate of cataract removal was 57.1% and 100% (P = .016), and the duration from first surgery to cataract surgery was 231.38 ±â€…241.23 and 156.36 ±â€…110.09 days (P = .428) for group A and group S, respectively. The rate of postoperative epiretinal membrane was 21.4% vs 25.0% (P = 1.000). Postoperative BCVA was associated with preoperative BCVA after multiple linear analysis. The primary and final anatomic success rate for PPV with air tamponade and SO in treating RRD with superior breaks were not statistically different. The rate of deferred cataract removal was higher in patients with SO as tamponade.


Assuntos
Catarata , Descolamento Retiniano , Vitreorretinopatia Proliferativa , Humanos , Descolamento Retiniano/etiologia , Vitreorretinopatia Proliferativa/complicações , Vitreorretinopatia Proliferativa/cirurgia , Vitrectomia/efeitos adversos , Estudos Retrospectivos , Acuidade Visual , Resultado do Tratamento , Óleos de Silicone , Catarata/complicações
15.
Int J Biol Macromol ; 231: 123233, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36642363

RESUMO

Hydrophobically modified sodium alginate stabilizes benzene in water emulsions. The stability of the emulsion is related to the interface properties at the mesoscopic scale, but the details of the polymer adsorption, conformation and organization at oil/water interfaces at the microscopic scale remain largely elusive. In this study, hydrophobically modified sodium alginate was used as a representative of amphiphilic polymers for prediction of distribution of HMSA at the oil/water interface by coarse-grained molecular dynamics simulation. The result showed that driven by the interaction energy between the hydrophobic segment and benzene, HMSA will actively accumulate at the oil/water interface. The HMSA molecules parallel to the oil/water interface prevent the hydrophobic segments in the micelles from approaching the oil/water interface, so that the micelles can exist stably by steric hindrance. This study would be helpful to understand the aggregation behavior of amphiphilic polymers at the oil/water interface, these results can have applications in diverse sectors such as drug, food industry, where polymers are used to stabilize emulsions.


Assuntos
Micelas , Simulação de Dinâmica Molecular , Emulsões/química , Benzeno , Polímeros/química
16.
Int J Pharm ; 644: 123296, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37553058

RESUMO

Bacterial vaginosis (BV) is a common dysbiosis of the human vaginal microbiota characterized by depletion of hydrogen peroxide and lactic acid-producing Lactobacillus bacteria and an overgrowth of certain facultative anaerobic bacteria. Although short-term cure rates following treatment with frontline antibiotics (most notably oral metronidazole (MNZ), clindamycin vaginal cream, and MNZ vaginal gel) are generally high, longer-term recurrence rates are an issue. The development of vaginal formulations offering continuous/sustained administration of antibiotic drugs over one or more weeks might prove useful in reducing recurrence. Here, we report the manufacture and preclinical testing of matrix-type vaginal rings offering sustained release of four 5-nitroimidazole antimicrobial drugs either being used clinically or having potential in treatment of BV - MNZ, tinidazole (TNZ), secnidazole (SNZ) and ornidazole (ONZ). All four drugs showed good compatibility with a medical-grade addition-cure silicone elastomer based upon thermal analysis experiments, and matrix-type rings containing 250 mg (3.125 %w/w) of each drug were successfully manufactured by reaction injection molding. 28-day in vitro drug release studies demonstrated root-time kinetics, with daily release rates of 25, 22, 9 and 6 mg/day½ for SNZ, ONZ, MNZ and TNZ, respectively. The rank order of drug release from rings correlated with the simple molecular permeability parameter S/V, where S is the measured drug solubility in silicone fluid and V is the drug molecular volume. The relative merits of SNZ and ONZ over MNZ (the current reference treatment) are discussed. The data support development of vaginal rings for sustained release of 5-nitroimidazole compounds for treatment of BV.


Assuntos
Dispositivos Anticoncepcionais Femininos , Ornidazol , Vaginose Bacteriana , Feminino , Humanos , Vaginose Bacteriana/tratamento farmacológico , Elastômeros de Silicone , Preparações de Ação Retardada/uso terapêutico , Administração Intravaginal , Metronidazol , Antibacterianos , Tinidazol , Ornidazol/uso terapêutico
17.
Bioresour Technol ; 384: 129339, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37343797

RESUMO

The aim of this study was to assess the effect of polylactic acid (PLA) on microbial community composition and core metabolism pathways in food waste (FW) composting. The presence of PLA negatively influenced microbial community richness and decreased respectively the abundance of Bacillus, Halocella and Cellvibrio at mesophilic, thermophilic and mature phases. Analysis of microbial metabolism at the gene level help to understand the mechanism in co-composting with FW and PLA. The expression of core functional genes related to lactide metabolism was stimulated by PLA degradation at thermophilic and mature phases. The sum of absolute abundance of functional genes that involved in first and second carbon oxidation of tricarboxylic acid cycle was decreased due to the existence of PLA. The transformation between 2-Oxoglutarate and Succinyl-CoA were interfered in thermophilic phase, which might result in the lower germination index in PLA group (115%) than that in control (186%).


Assuntos
Compostagem , Eliminação de Resíduos , Alimentos , Poliésteres , Solo
18.
Environ Pollut ; 310: 119859, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35944782

RESUMO

The environmental risks of microplastics (MPs) have raised an increasing concern. However, the effects of MPs in anaerobic digestion (AD) systems of waste activated sludge (WAS), especially on the fate of antibiotic resistance genes (ARGs), have not been clearly understood. Herein, the variation and interaction of digestion performance, microbial communities and ARGs during AD process of WAS in the presence of polyethylene (PE) MPs with two sizes, PE MPs-180µm and PE MPs-1mm, were investigated. The results showed that the presence of PE MPs, especially PE MPs-1mm, led to the increased hydrolysis of soluble polysaccharides and proteins and the accumulation of volatile fatty acids. The methane production decreased by 6.1% and 13.8% in the presence of PE MPs-180µm and PE MPs-1mm, respectively. Together with this process, hydrolytic bacteria and acidogens were enriched, and methanogens participating in acetoclastic methanogenesis were reduced. Meanwhile, ARGs were enriched obviously by the presence of PE MPs, the abundances of which in PE MPs-180µm and PE MPs-1mm groups were 1.2-3.0 times and 1.5-4.0 times higher than that in the control by the end of AD. That was associated with different co-occurrence patterns between ARGs and bacterial taxa and the enrichment of ARG-hosting bacteria caused by the presence of PE MPs. Together these results suggested the adverse effects of PE MPs on performance and ARGs removal during AD process of WAS through inducing the changes of microbial populations.


Assuntos
Microbiota , Esgotos , Anaerobiose , Antibacterianos , Bactérias , Digestão , Resistência Microbiana a Medicamentos , Genes Bacterianos , Microplásticos , Plásticos , Polietileno
19.
ACS Appl Mater Interfaces ; 14(32): 36315-36330, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35929013

RESUMO

The formation and metabolic balance of bone tissue is a controllable process of biomineralization, which is regulated by various cells, biomolecules, and ions. Enzyme molecules play an important role in this process, and alkaline phosphatase (ALP) is one of the most critical factors. In this study, inspired by the process of bone biomineralization, a biomimetic strategy is achieved for the preparation of mineralized ALP nanoparticles (MALPNs), by taking advantages of the unique reaction between ALP and calcium ions in Dulbecco's modified Eagle's medium. Benefiting from the mild biomineralization reaction, the MALPN system highly maintains the activity of ALP. Furthermore, the in vitro studies show that the MALPN system significantly enhances the proliferation of bone marrow mesenchymal stem cells and upregulates their osteogenic differentiation. When evaluated as synthetic graft materials for bone regeneration, the MALPN-incorporated gelatin methacryloyl graft shows excellent mechanical properties, a sustained release profile of ALP, and high biocompatibility and efficacy in guiding bone regeneration and vascularization for critical-sized rat calvarial defect. Moreover, we also demonstrate that the biomimetic mineralization strategy can be adopted for other proteins such as acid phosphatase, bovine serum albumin, fibrinogen, and gelatin, suggesting its universality for constructing mineralized protein-/enzyme-based bioactive materials for the application of tissue regeneration.


Assuntos
Materiais Biocompatíveis , Osteogênese , Fosfatase Alcalina/metabolismo , Animais , Materiais Biocompatíveis/farmacologia , Regeneração Óssea , Diferenciação Celular/fisiologia , Gelatina , Íons , Metacrilatos , Osteogênese/fisiologia , Ratos , Alicerces Teciduais
20.
Int J Biol Macromol ; 190: 11-18, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34478791

RESUMO

The development of advanced energy storage systems, such as rechargeable batteries and supercapacitors (SCs), is one of the great challenges related to energy demand with the rapid development of world economy. Herein, a three-dimensional hierarchical porous lignin-derived carbon/WO3 (HPC/WO3) was prepared by carbonization and solvothermal process. This electrode material for supercapacitor can be operated at a wide voltage window range of -0.4 V to 1.0 V. More importantly, 3HPC/WO3 with ultrahigh mass loading (~3.56 mg cm-2) has excellent specific capacitance of 432 F g-1 at 0.5 A g-1 and cycling stability of 86.6% after 10,000 cycles at 10 A g-1. The as-assembled asymmetrical supercapacitor shows an energy density of 34.2 W h kg-1 at a power density of 237 W kg-1 and energy density of 16 W h kg-1 at a power density is 14,300 W kg-1. A solid-state planar micro-supercapacitor (MSC) was fabricated using HPC/WO3 nanocomposites. Moreover, the calculated specific capacity of MSC was 20 mF cm-2 in polyvinyl alcohol-sulfuric acid gel electrolyte. Overall, through the reasonable design of HPC/WO3 nanocomposite materials and the efficient assembly of MSCs, the performance of the device was greatly improved, thus providing a clear strategy for the development of energy storage devices.


Assuntos
Carbono/química , Capacitância Elétrica , Lignina/química , Óxidos/química , Tungstênio/química , Adsorção , Eletroquímica , Nitrogênio/química , Porosidade , Difração de Raios X
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