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1.
J Environ Sci (China) ; 139: 170-181, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38105045

RESUMEN

The nanoscale zinc oxide (n-ZnO) was used in food packages due to its superior antibacterial activity, resulting in potential intake of n-ZnO through the digestive system, wherein n-ZnO interacted with saliva. In recent, facet engineering, a technique for controlling the exposed facets, was applied to n-ZnO, whereas risk of n-ZnO with specific exposed facets in saliva was ignored. ZnO nanoflakes (ZnO-0001) and nanoneedles (ZnO-1010) with the primary exposed facets of {0001} and {1010} respectively were prepared in this study, investigating stability and toxicity of ZnO-0001 and ZnO-1010 in synthetic saliva. Both ZnO-0001 and ZnO-1010 partially transformed into amorphous Zn3(PO4)2 within 1 hr in the saliva even containing orgnaic components, forming a ZnO-Zn3(PO4)2 core-shell structure. Nevertheless, ZnO-1010 relative to ZnO-0001 would likely transform into Zn3(PO4)2, being attributed to superior dissolution of {1010} facet due to its lower vacancy formation energy (1.15 eV) than {0001} facet (3.90 eV). The toxicity of n-ZnO to Caco-2 cells was also dependent on the primary exposed facet; ZnO-0001 caused cell toxicity through oxidative stress, whereas ZnO-1010 resulted in lower cells viability than ZnO-0001 through oxidative stress and membrane damage. Density functional theory calculations illustrated that ·O2- was formed and released on {1010} facet, yet O22- instead of ·O2- was generated on {0001} facet, leading to low oxidative stress from ZnO-0001. All findings demonstrated that stability and toxicity of n-ZnO were dependent on the primary exposed facet, improving our understanding of health risk of nanomaterials.


Asunto(s)
Óxido de Zinc , Humanos , Óxido de Zinc/toxicidad , Óxido de Zinc/química , Células CACO-2 , Saliva , Estrés Oxidativo
2.
Eur J Epidemiol ; 35(9): 821-833, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32533373

RESUMEN

Periodontal disease (PD) is common and increases cardiovascular diseases. However, it is unclear whether PD is associated with increased risk of dementia. We carried out a systematic review and meta-analysis to investigate the influence of PD on dementia. We projected the number of dementia cases to be saved by reducing PD prevalence in the world. We searched cohort and case-control studies reporting the association of PD with all dementia (or any specific type of dementia) through PubMed, MEDLINE, PsycINFO, SocINDEX, CINHAL, and CNKI until 7th November 2018. Five cohorts and seven case-control studies were identified for review. We pooled eligible data to calculate relative risk (RR) of dementia in relation to PD and computed the number of dementia cases saved through reducing PD prevalence. Of 12 studies, six were undertaken in Asia, four in Europe and two in America. Eleven studies showed a positive association between PD and the risk of dementia, of which 10 were significant, and one reported a non-significant inverse association. Overall their quality was good. Pooled RR of dementia in relation to PD from all high quality studies was 1.38 (95%CI 1.01-1.90); in the five cohorts was 1.18 (1.06-1.31) and in the two case-control studies 2.25 (1.48-3.42). A 50% reduction in the current prevalence of 20% of PD in the population could save 850,000 (630,000-1,420,000) patients with dementia in the world. PD could increase the risk of incident dementia. Preventing and treating PD could contribute to controlling the global epidemic of dementia.


Asunto(s)
Enfermedad de Alzheimer/epidemiología , Demencia/epidemiología , Salud Bucal/estadística & datos numéricos , Enfermedades Periodontales/complicaciones , Enfermedad de Alzheimer/complicaciones , Demencia/complicaciones , Humanos , Enfermedades Periodontales/epidemiología , Periodontitis/complicaciones , Periodontitis/epidemiología , Prevalencia
3.
Mol Pharm ; 15(1): 83-96, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29141139

RESUMEN

Synthetic high density lipoprotein nanoparticles (sHDLs) capable of mobilizing excess cholesterol from atherosclerotic arteries and delivering it to the liver for elimination have been shown to reduce plaque burden in patients. Unfortunately, sHDLs have a narrow therapeutic index and relative to the endogenous HDL shorter circulation half-life. Surface modification with polyethylene glycol (PEG) was investigated for its potential to extend sHDL circulation in vivo. Various amounts (2.5, 5, and 10%) and different chain lengths (2 and 5 kDa) of PEG-modified lipids were incorporated in sHDL's lipid membrane. Incorporating PEG did not reduce the ability of sHDL to facilitate cholesterol efflux, nor did it inhibit cholesterol uptake by the liver cells. By either adding more PEG or using PEG of longer chain lengths, the circulation half-life was extended. Addition of PEG also increased the area under the curve for the phospholipid component of sHDL (p < 0.05), but not for the apolipoprotein A-I peptide component of sHDL, suggesting sHDL is remodeled by endogenous lipoproteins in vivo. The extended phospholipid circulation led to a higher mobilization of plasma free cholesterol, a biomarker for facilitation of reverse cholesterol transport. The area under the cholesterol mobilization increased about 2-4-fold (p < 0.05), with greater increases observed for longer PEG chains and higher molar percentages of incorporated PEGylated lipids. Mobilized cholesterol was associated primarily with the HDL fraction, led to a transient increase in VLDL cholesterol, and returned to baseline 24 h postdose. Overall, PEGylation of sHDL led to beneficial changes in sHDL particle pharmacokinetic and pharmacodynamic behaviors.


Asunto(s)
Lipoproteínas HDL/química , Nanopartículas/química , Polietilenglicoles/química , Apolipoproteína A-I/química , Colesterol/química
4.
Nanomedicine ; 13(6): 1869-1878, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28434931

RESUMEN

Synthetic high-density lipoprotein nanoparticles (sHDL) are a valuable class of nanomedicines with established animal safety profile, clinical tolerability and therapeutic efficacy for cardiovascular applications. In this study we examined how the scavenger receptor B-I-mediated (SR-BI) tumor-targeting ability of sHDL, long plasma circulation half-life, and small particle size (9.6±0.2nm) impacted sHDL accumulation in SR-BI positive colorectal carcinoma cells, 3D tumor spheroids, and in vivo xenografts. We compared tumor accumulation of sHDL with that of liposomes (LIP, 130.7±0.8nm), pegylated liposomes (PEG-LIP, 101±2nm), and pegylated sHDL (12.1±0.1nm), all prepared with the same lipid components. sHDL penetrated deep (210µm) into tumor spheroids and exhibited 12- and 3-fold higher in vivo solid tumor accumulation, compared with LIP (p<0.01) and PEG-LIP (p<0.05), respectively. These results suggest that sHDL with established human safety possess promising intrinsic tumor-targeted properties.


Asunto(s)
Neoplasias Colorrectales/tratamiento farmacológico , Sistemas de Liberación de Medicamentos , Lipoproteínas HDL/metabolismo , Liposomas/química , Nanopartículas/química , Polietilenglicoles/química , Antineoplásicos/farmacología , Neoplasias Colorrectales/metabolismo , Humanos , Tamaño de la Partícula , Receptores Depuradores de Clase B/metabolismo , Esferoides Celulares , Células Tumorales Cultivadas
5.
J Fluoresc ; 26(1): 121-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26511954

RESUMEN

It was recently reported that, besides UV irradiated polymerization, polymerization of diacetylene compounds could also been initiated by radicals generated from enzyme catalyzed hydrogen peroxide (H2O2) decomposition. A new optical sensing method for H2O2 was proposed based on this phenomenon. However, the sensitivity of this method is relatively lower than existed ones. In the present work, phenylboronic acid (PBA) functionalized 10, 12-pentacosadiynoic acid (PDA-PBA) was synthesized and its vesicles were formed successfully as colorimetric sensor for H2O2 detection. It was found that color change during the polymerization of vesicles composed of the PBA modified monomer is much stronger than that of the non-modified one. The response of PDA-PBA vesicles to H2O2 is 16 times more sensitive than that of the PDA. The absorption of PDA-PBA at 650 nm is linearly related to the concentration of H2O2 and a detection limit of ~5 µM could be achieved.


Asunto(s)
Ácidos Borónicos/química , Peróxido de Hidrógeno/análisis , Polímeros/química , Poliinos/química , Estructura Molecular , Polímero Poliacetilénico , Espectrofotometría Ultravioleta
6.
Sci Total Environ ; 930: 172511, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38641106

RESUMEN

The co-occurrence of nanoplastics (NPs) and antibiotics in the environment is a growing concern for ecological safety. As NPs age in natural environments, their surface properties and morphology may change, potentially affecting their interactions with co-contaminants such as antibiotics. It is crucial to understand the effect of aging on NPs adsorption of antibiotics, but detailed studies on this topic are still scarce. The study utilized the photo-Fenton-like reaction to hasten the aging of polystyrene nanoplastics (PS-NPs). The impact of aging on the adsorption behavior of norfloxacin (NOR) was then systematically examined. The results showed a time-dependent rise in surface oxygen content and functional groups in aged PS-NPs. These modifications led to noticeable physical changes, including increased surface roughness, decreased particle size, and improved specific surface area. The physicochemical changes significantly increased the adsorption capacity of aged PS-NPs for norfloxacin. Aged PS-NPs showed 5.03 times higher adsorption compared to virgin PS-NPs. The adsorption mechanism analysis revealed that in addition to the electrostatic interactions, van der Waals force, hydrogen bonding, π-π* interactions and hydrophobic interactions observed with virgin PS-NPs, aged PS-NPs played a significant role in polar interactions and pore-filling mechanisms. The study highlights the potential for aging to worsen antibiotic risk in contaminated environments. This study not only enhances the comprehension of the environmental behavior of aged NPs but also provides a valuable basis for developing risk management strategies for contaminated areas.


Asunto(s)
Norfloxacino , Poliestirenos , Norfloxacino/química , Adsorción , Poliestirenos/química , Antibacterianos/química , Nanopartículas/química , Contaminantes Químicos del Agua/química , Procesos Fotoquímicos , Modelos Químicos
7.
Int J Biol Macromol ; 266(Pt 2): 131370, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38580027

RESUMEN

Garlic essential oil (GEO) is a potential natural antioxidant and antimicrobial agent for food preservation, but its intrinsic low water-solubility, high volatility and poor stability severely limit its application and promotion. In this work, we investigated the synergistic stabilization of the GEO-in-water nanoemulsion using carboxymethyl chitosan (CCS) and Tween 80 (TW 80). Additionally, the nanoemulsion was fabricated through high-pressure microfluidization and utilized for the coating-mediated preservation of chilled pork. The garlic essential oil nanoemulsion (GEON) with 3.0 % CCS and 3.0 % TW 80 exhibited more homogeneous droplet size (around 150 nm) and narrower size distribution, while maintained long-term stability with no significant change in size during 30 d storage. Compared with free GEO, the GEONs exhibited a higher scavenging capacity to DPPH and ABTS free radicals as well as higher inhibitory effects against Escherichia coli and Staphylococcus aureus, suggesting that the encapsulation of GEO in nanoemulsion considerably improved its antioxidant and antibacterial activities. Furthermore, the results of coating preservation experiments showed that the GEON coating effectively expanded the shelf-life of chilled fresh pork for approximately one week. Altogether, this study would guide the development of GEO-loaded nanoemulsions, and promote GEON as a promising alternative for coating preservation of chilled fresh meat.


Asunto(s)
Antioxidantes , Quitosano , Quitosano/análogos & derivados , Emulsiones , Conservación de Alimentos , Ajo , Aceites Volátiles , Polisorbatos , Quitosano/química , Quitosano/farmacología , Aceites Volátiles/química , Aceites Volátiles/farmacología , Emulsiones/química , Conservación de Alimentos/métodos , Animales , Polisorbatos/química , Antioxidantes/farmacología , Antioxidantes/química , Porcinos , Ajo/química , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Carne de Cerdo
8.
Adv Healthc Mater ; 13(12): e2304156, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38271691

RESUMEN

Despite considerable interest in medical and pharmaceutical fields, there remains a notable absence of functional textiles that concurrently exhibit antibacterial and antioxidant properties. Herein, a new composite fabric constructed using nanostructured bacterial cellulose (BC) covalently-linked with cerium oxide nanoparticles (BC@CeO2NPs) is introduced. The synthesis of CeO2NPs on the BC is performed via a microwave-assisted, in situ chemical deposition technique, resulting in the formation of mixed valence Ce3+/Ce4+ CeO2NPs. This approach ensures the durability of the composite fabric subjected to multiple washing cycles. The Reactive oxygen species (ROS) scavenging activity of CeO2NPs and their rapid and efficient eradication of >99% model microbes, such as Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus remain unaltered in the composite. To demonstrate the feasibility of incorporating the fabric in marketable products, antimicrobial face masks are fabricated with filter layers made of BC@CeO2NPs cross-linked with propylene or cotton fibers. These masks exhibit complete inhibition of bacterial growth in the three bacterial strains, improved breathability compared to respirator masks and enhanced filtration efficiency compared to single-use surgical face masks. This study provides valuable insights into the development of functional BC@CeO2NPs biotextiles in which design can be extended to the fabrication of medical dressings and cosmetic products with combined antibiotic, antioxidant and anti-inflammatory activities.


Asunto(s)
Antibacterianos , Antioxidantes , Celulosa , Cerio , Escherichia coli , Pseudomonas aeruginosa , Staphylococcus aureus , Celulosa/química , Cerio/química , Cerio/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antioxidantes/química , Antioxidantes/farmacología , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Máscaras , Textiles , Humanos , Especies Reactivas de Oxígeno/metabolismo , Nanopartículas/química , Pruebas de Sensibilidad Microbiana
9.
Virol Sin ; 39(2): 290-300, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38331038

RESUMEN

Coxsackievirus B3 (CVB3) is the pathogen causing hand, foot and mouth disease (HFMD), which manifests across a spectrum of clinical severity from mild to severe. However, CVB3-infected mouse models mainly demonstrate viral myocarditis and pancreatitis, failing to replicate human HFMD symptoms. Although several enteroviruses have been evaluated in Syrian hamsters and rhesus monkeys, there is no comprehensive data on CVB3. In this study, we have first tested the susceptibility of Syrian hamsters to CVB3 infection via different routes. The results showed that Syrian hamsters were successfully infected with CVB3 by intraperitoneal injection or nasal drip, leading to nasopharyngeal colonization, acute severe pathological injury, and typical HFMD symptoms. Notably, the nasal drip group exhibited a longer viral excretion cycle and more severe pathological damage. In the subsequent study, rhesus monkeys infected with CVB3 through nasal drips also presented signs of HFMD symptoms, viral excretion, serum antibody conversion, viral nucleic acids and antigens, and the specific organ damages, particularly in the heart. Surprisingly, there were no significant differences in myocardial enzyme levels, and the clinical symptoms resembled those often associated with common, mild infections. In summary, the study successfully developed severe Syrian hamsters and mild rhesus monkey models for CVB3-induced HFMD. These models could serve as a basis for understanding the disease pathogenesis, conducting pre-trial prevention and evaluation, and implementing post-exposure intervention.


Asunto(s)
Modelos Animales de Enfermedad , Enterovirus Humano B , Enfermedad de Boca, Mano y Pie , Macaca mulatta , Mesocricetus , Animales , Enfermedad de Boca, Mano y Pie/virología , Enfermedad de Boca, Mano y Pie/patología , Enterovirus Humano B/patogenicidad , Anticuerpos Antivirales/sangre , Cricetinae , Femenino , Esparcimiento de Virus , Nasofaringe/virología , Masculino
10.
Yao Xue Xue Bao ; 48(2): 298-304, 2013 Feb.
Artículo en Zh | MEDLINE | ID: mdl-23672030

RESUMEN

To develop a core-shell structure pDNA-CaPi-PLGA nanoparticles (CS-pDNA-CaPi-PLGA-NPs), calcium phosphate-pDNA nano complexes (CaPi-pDNA) were encapsulated inside of PLGA shells. The characteristics of the nanoparticles, including morphology, average particle size, zeta potential, entrapment efficiency, loading efficiency, stability in medium, pDNA protection ability from nuclease degradation, in vitro release, cytotoxicity and cell transfection were investigated and compared with the embedded structured CaPi modified PLGA nanoparticles (embedded-pDNA-CaPi-PLGA-NPs). The results showed that the obtained CS-pDNA-CaPi-PLGA-NPs were spherical in shape with an average particle size of (155 +/- 4.5) nm, zeta potentials of (-0.38 +/- 0.1) mV, entrapment efficiency of (80.56 +/- 2.5)% and loading efficiency of (1.16 +/- 0.04)%. The CS-pDNA-CaPi-PLGA-NPs were stable in the release media and could protect pDNA against nuclease degradation. And they also exhibited sustained release of pDNA in vitro. The highest gene transfection efficiency of the CS-pDNA-CaPi-PLGA-NPs in vitro reached (24.66 +/- 0.46)% (after 72 h transfection), which was significantly higher than that of free pDNA [(0.33 +/- 0.04)%, P < 0.01] and the pDNA-PLGA-NPs [(1.5 +/- 0.07)%, P < 0.01]. Besides, the transfection lasted for longer time than that of embedded-pDNA-CaPi-PLGA-NPs and the cytotoxicity of it was significantly lower than that of PEI (P < 0.01). These results indicate that CS-pDNA-CaPi-PLGA-NPs are a promising non-viral gene vector. Key words: gene delivery system; polylactic-co-glycolic acid; calcium phosphate; nanoparticle


Asunto(s)
Fosfatos de Calcio/administración & dosificación , ADN/administración & dosificación , Ácido Láctico/administración & dosificación , Ácido Poliglicólico/administración & dosificación , Fosfatos de Calcio/química , Fosfatos de Calcio/toxicidad , Supervivencia Celular/efectos de los fármacos , ADN/química , ADN/toxicidad , Portadores de Fármacos , Vectores Genéticos , Células HEK293 , Humanos , Ácido Láctico/química , Nanopartículas , Tamaño de la Partícula , Plásmidos/genética , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Transfección
11.
Int J Nanomedicine ; 18: 4683-4703, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37608819

RESUMEN

Purpose: Dental pulp stem cell-derived exosomes (DPSC-EXO), which have biological characteristics similar to those of metrocytes, have been found to be closely associated with tissue regeneration. Periodontitis is an immune inflammation and tissue destructive disease caused by plaque, resulting in alveolar bone loss and periodontal epithelial destruction. It is not clear whether DPSC-EXO can be used as an effective therapy for periodontal regeneration. The purpose of this study was not only to verify the effect of DPSC-EXO on reducing periodontitis and promoting periodontal tissue regeneration, but also to reveal the possible mechanism. Methods: DPSC-EXO was isolated by ultracentrifugation. Then it characterized by transmission electron microscope (TEM), nanoparticle tracking analysis (NTA) and Western Blot. In vitro, periodontal ligament stem cells (PDLSCs) were treated with DPSC-EXO, the abilities of cell proliferation, migration and osteogenic potential were evaluated. Furthermore, we detected the expression of IL-1ß, TNF-αand key proteins in the IL-6/JAK2/STAT3 signaling pathway after simulating the inflammatory environment by LPS. In addition, the effect of DPSC-EXO on the polarization phenotype of macrophages was detected. In vivo, the experimental periodontitis in rats was established and treated with DPSC-EXO or PBS. After 4 weeks, the maxillae were collected and detected by micro-CT and histological staining. Results: DPSC-EXO promoted the proliferation, migration and osteogenesis of PDLSCs in vitro. DPSC-EXO also regulated inflammation by inhibiting the IL-6/JAK2/STAT3 signaling pathway during acute inflammatory stress. In addition, the results showed that DPSC-EXO could polarize macrophages from the M1 phenotype to the M2 phenotype. In vivo, we found that DPSC-EXO could effectively reduce alveolar bone loss and promote the healing of the periodontal epithelium in rats with experimental periodontitis. Conclusion: DPSC-EXO plays an important role in inhibiting periodontitis and promoting tissue regeneration. This study provides a promising acellular therapy for periodontitis.


Asunto(s)
Pérdida de Hueso Alveolar , Exosomas , Periodontitis , Animales , Ratas , Ligamento Periodontal , Pérdida de Hueso Alveolar/terapia , Pulpa Dental , Interleucina-6 , Osteogénesis , Periodontitis/terapia , Antiinflamatorios , Inflamación
12.
Adv Healthc Mater ; 12(1): e2200807, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36177664

RESUMEN

Since the first surgery 50 years ago, cochlear implantation (CI) is the major treatment for patients with severe sensorineural hearing loss. However, unexpected foreign body reactions (FBRs) after surgery are reported in 90% of CI recipients, resulting in the formation of fibrosis in the cochlea and progressive residual hearing loss. Zwitterion modification is universally used to reduce bio-fouling and suppress FBRs but never for CI. In the present study, a zwitterionic coating is developed, which is composed of poly sulfobetaine methacrylate (PSB) and polydopamine (PDA) for cochlear implants. The PSB-PDA coating shows a series of characters for an ideal anti-FBRs material, including super-hydrophilicity, low protein and cell adsorption, long-term stability, and high biocompatibility. Compared to the uncoated controls, PSB-PDA coating inhibits the activation of macrophages and reduces the release of inflammatory factors (TNF-α, IL-1ß, NO) and fibrosis-related factors (TGF-ß1, α-SMA, collagen I). PSB-PDA coated electrode arrays suppress fibrosis completely and preserve residual hearing significantly in rat CI models. These results suggest that PSB-PDA coating is a novel strategy for anti-fibrosis to improve the outcomes of CI.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Pérdida Auditiva , Ratas , Animales , Implantación Coclear/efectos adversos , Pérdida Auditiva/etiología , Implantes Cocleares/efectos adversos , Polímeros/farmacología
13.
Sci Total Environ ; 886: 164033, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37169191

RESUMEN

Concerns regarding the environmental hazards and health risks of nanoplastics (NPs) are increasing. However, quantifying of NPs in vivo remains challenging. In this study, we propose a strategy for using magnetic resonance imaging (MRI) to quantify NPs internalized by mouse macrophages. Model NPs (Fe3O4@PS) with more homogeneous sizes and morphologies were obtained by encapsulating Fe3O4 in polystyrene. A standard curve was generated by linearly fitting the intensity and concentration charts to the Fe3O4@PS MRI data. The mass of Fe3O4@PS captured by the mouse macrophages was estimated using a standard curve. An explanation of how the standard curves were created and used is provided in the text. The accuracy of the MRI results was demonstrated using, inductively coupled plasma (ICP). Quantitative results from MRI and ICP revealed that the mouse macrophage uptake increased as NPs concentrations decreased. According to the ICP results, when the NPs exposure concentration was 10 µg/mL, the uptake rate by mouse macrophages was 63.0 %. The quantitative MRI results were slightly lower than those for ICP, with an uptake rate of 57.7 % in mouse macrophages at the same concentration. Therefore, MRI provides a new perspective for quantitative NPs analysis.


Asunto(s)
Nanopartículas , Contaminantes Químicos del Agua , Animales , Ratones , Microplásticos , Imagen por Resonancia Magnética/métodos , Poliestirenos/toxicidad , Transporte Biológico
14.
Nat Commun ; 14(1): 6401, 2023 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-37828020

RESUMEN

Pesticides are widely used to increase agricultural productivity, however, weak adhesion and deposition lead to low efficient utilization. Herein, we prepare a nanopesticide formulation (tebuconazole nanopesticides) which is leaf-adhesive, and water-dispersed via a rapid nanoparticle precipitation method, flash nanoprecipitation, using temperature-responsive copolymers poly-(2-(dimethylamino)ethylmethylacrylate)-b-poly(ε-caprolactone) as the carrier. Compared with commercial suspensions, the encapsulation by the polymer improves the deposition of TEB, and the contact angle on foliage is lowered by 40.0°. Due to the small size and strong van der Waals interactions, the anti-washing efficiency of TEB NPs is increased by 37% in contrast to commercial ones. Finally, the acute toxicity of TEB NPs to zebrafish shows a more than 25-fold reduction as compared to commercial formulation indicating good biocompatibility of the nanopesticides. This work is expected to enhance pesticide droplet deposition and adhesion, maximize the use of pesticides, tackling one of the application challenges of pesticides.


Asunto(s)
Plaguicidas , Agua , Animales , Temperatura , Pez Cebra , Polímeros , Hojas de la Planta
15.
Nanoscale ; 15(35): 14365-14379, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37609757

RESUMEN

Cerium oxide nanozymes (CeO2NZs) are attracting vast attention due to their antioxidant and catalytic properties and mimic the activities of multiple endogenous enzymes. However, as is the case for nanomedicines in general, the success in showing their unique medical applications has not been matched by an understanding of their pharmacokinetics, which is delaying their implementation in clinical settings. Furthermore, the data of their modifications in body fluids and the impact on their activity are scarce. Herein, two types of widely used CeO2NZs, electrostatically stabilized and coated with a mesoporous silica shell, were exposed to simulated saliva and lung, gastric and intestinal fluids, and cell culture media. Their physicochemical modifications and bioactivity were tracked over time up to 15 days combining the data of different characterization techniques and biological assays. The results show that the biocompatibility and antioxidant activity are retained in all cases despite the different evolution behaviors in different fluids, including agglomeration. This work provides an experimental basis from a pharmacokinetic perspective that supports the therapeutic effectiveness of CeO2NZs observed in vivo for the treatment of many conditions related to chronic inflammation and cancer, and suggests that they can be safely administered through different portals of entry including intravenous injection, oral ingestion or inhalation.


Asunto(s)
Líquidos Corporales , Saliva , Antioxidantes/farmacología , Bioensayo , Catálisis
16.
Comput Methods Biomech Biomed Engin ; 26(13): 1523-1531, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36382359

RESUMEN

Saliva blood mixed liquid (SBML) appears in oral surgery, such as scaling and root planning, and it affects surgical vision and causes discomfort to the patient. However, removing SBML, i.e. frequent aspiration of the mixed liquid, is a routine task involving heavy workload and interruption of oral surgery. Therefore, it is valuable to alternate the manual mode by autonomous robotic technique. The robotic system is designed consisting of an RGB-D camera, a manipulator, a disposable oral aspirator. An algorithm is developed for detection of SBML. Path planning method is also addressed for the distal end of the aspirator. A workflow for removing SBML is presented. 95% of the area of the SBML in the oral cavity was removed after liquid aspiration among a group of ten SBML aspiration experiments. This study provides the first result of the autonomous aspirating robot (AAR) for removing SBML in oral surgery, demonstrating that SBML can be removed by the autonomous robot, freeing stomatology surgeon from tedious work.


Asunto(s)
Procedimientos Quirúrgicos Orales , Robótica , Humanos , Saliva
17.
J Control Release ; 361: 297-313, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37343723

RESUMEN

Spray-dried poly(lactic-co-glycolic acid) (PLGA) peptide-loaded microspheres have demonstrated similar long-term in vitro release kinetics compared to those produced by the solvent evaporation method and commercial products. However, the difficult-to-control initial burst release over the first 24 h after administration presents an obstacle to product development and establishing bioequivalence. Currently, detailed information about underlying mechanisms of the initial burst release from microspheres is limited. We investigated the mechanism and extent of initial burst release using 16 previously developed spray-dried microsphere formulations of the hormone drug, leuprolide acetate, with similar composition to the commercial 1-month Lupron Depot® (LD). The burst release kinetics was measured with a previously validated continuous monitoring system as well as traditional sample-and-separate methods. The changes in pore structure and polymer permeability were investigated by SEM imaging and the uptake of a bodipy-dextran probe. In vitro results were compared to pharmacokinetics in rats over the same interval. High-burst, spray-dried microspheres were differentiated in the well-mixed continuous monitoring system but reached an upper limit when measured by the sample-and-separate method. Pore-like occlusions observed by confocal microscopy in some formulations indicated that particle swelling may have contributed to probe diffusion through the polymer phase and showed the extensive internal pore structure of spray-dried particles. Continuous monitoring revealed a rapid primary (1°) phase followed by a constant-rate secondary (2°) release phase, which comprised ∼80% and 20% of the 24-hr release, respectively. The ratio of 1° phase duration (t1°) and the characteristic probe diffusion time (τ) was highly correlated to 1° phase release for spray dried particles. Of the four spray-dried formulations administered in vivo, three spray-dried microspheres with similar polymer density showed nearly ideal linear correlation between in vivo absorption and well-mixed in vitro release kinetics over the first 24 h. By contrast, the more structurally dense LD and a more-dense in-house formulation showed a slight lag phase in vivo relative to in vitro. Furthermore, in vitro dimensionless times (tburst/τ) were highly correlated with pharmacokinetic parameters for spray-dried microspheres but not for LD. While the correlation of increases in effective probe diffusion and 1° phase release strongly suggests diffusion through the polymer matrix as a major release mechanism both in vitro and in vivo, a fixed lower limit for this release fraction implies an alternative release mechanism. Overall, continuous monitoring release and probe diffusion appears to have potential in differentiating between leuprolide formulations and establishing relationships between in vitro release and in vivo absorption during the initial burst period.


Asunto(s)
Leuprolida , Polímeros , Ratas , Animales , Leuprolida/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Microesferas , Polímeros/química , Solventes , Tamaño de la Partícula
18.
J Oral Maxillofac Surg ; 70(5): 1192-8, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21783300

RESUMEN

PURPOSE: Oral mucosal melanoma (OMM) is a rare disease associated with a very poor prognosis. Because well-established treatment protocols for OMM are in short supply, prognostic information regarding recent treatment modalities for this disease were sought. PATIENTS AND METHODS: A retrospective chart review was performed of 61 patients who were treated for OMM from 1998 through 2005. The clinical features and treatment modalities were identified and correlated with the outcomes. RESULTS: There were 41 male and 20 female patients (ratio, 2.1:1) with a mean age of 54.1 years. The mean follow-up was 31.9 months, and the overall 2-year and 5-year survival rates were 51.1% and 30.3%, respectively. According to the seventh edition of the American Joint Committee on Cancer staging system, there were 31 patients (50.8%) with stage III tumors. A more advanced stage and a tumor of at least 2 cm were associated with worse survival (P < .001 and P = .036, respectively). Elective lymph node dissection and biochemotherapy were not associated with a higher total survival rate (P = .53 and P = .76, respectively). CONCLUSIONS: OMM has a male predilection. The seventh edition of the American Joint Committee on Cancer stage and tumor size are effective prognostic parameters for patients with OMM. The American Joint Committee on Cancer staging system provides useful information for predicting the ultimate outcome and should be used as the primary staging system. Elective node dissection and adjuvant biochemotherapy offer no additional advantage in increasing the patient survival rate. A wait-and-see policy is advocated for patients with clinical stage N0 cancer.


Asunto(s)
Melanoma/terapia , Mucosa Bucal/patología , Neoplasias de la Boca/terapia , Espera Vigilante , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Procedimientos Quirúrgicos Electivos , Femenino , Estudios de Seguimiento , Predicción , Neoplasias Gingivales/terapia , Humanos , Escisión del Ganglio Linfático , Masculino , Melanoma/secundario , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neoplasias Palatinas/terapia , Pronóstico , Estudios Retrospectivos , Factores Sexuales , Tasa de Supervivencia , Resultado del Tratamiento
19.
ACS Appl Mater Interfaces ; 14(26): 29577-29587, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35732055

RESUMEN

Microneedle (MN) patches enable simple self-administration of drugs via the skin. In this study, we sought to deliver drug-loaded microspheres (MSs) using MN patches and found that the poly(lactic-co-glycolic acid) (PLGA) MSs failed to localize in the MN tips during fabrication, thereby decreasing their delivered dose and delivery efficiency into skin. We determined that surface interactions between the hydrophobic MSs and the poly(dimethylsiloxane) (PDMS) mold caused MSs to adhere to the mold surface during casting in aqueous formulations, with hydrophobic interactions largely responsible for adhesion. Further studies with polystyrene MSs that similarly carry a negative charge like the PLGA MSs demonstrated both repulsive electrostatic interactions as well as adhesive hydrophobic interactions. Reducing hydrophobic interactions by addition of a surfactant or modifying mold surface properties increased MS loading into MN tips and delivery into porcine skin ex vivo by 3-fold. We conclude that surface interactions affect the loading of hydrophobic MSs into MN patches during aqueous fabrication procedures and that their modulation with the surfactant can increase loading and delivery efficiency.


Asunto(s)
Ácido Láctico , Ácido Poliglicólico , Animales , Sistemas de Liberación de Medicamentos , Ácido Láctico/química , Microesferas , Agujas , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Tensoactivos , Porcinos
20.
Oxid Med Cell Longev ; 2022: 2422618, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35186182

RESUMEN

The vermilion of the human lip, covered by a skinny epithelium with little melanin, is quite susceptible to damage from ultraviolet (UV) radiation exposure. However, commercial sunscreen filters and indelible dyes used in lipsticks can cause health hazards after percutaneous absorption or accidentally oral administration. Inspired by plant pigmentation as natural filters to protect themselves against overexposure to UV, safer bio-based sunscreens of cellulose enveloped with anthocyanin (AN) were developed using bionic design. Cellulose nanocrystals (CNC), derived from acid hydrolysis of cellulose, reinforced enhancement of UV absorption and shielding properties of AN. This innovation addresses the issue that naturally sourced UV filter application to sunscreen does not achieve a desired sun protection factor (SPF) value because of the low specific extinction value (E1,1). We also stated that the diverse formula of anthocyanin sunscreen lipsticks with CNC exhibited 10 times more SPF value than AN alone. Furthermore, they possess competitive benefits such as pleasing texture, superior adhesion, impermeable, nonphototoxicity, ease of application, and removal. This work provides a promising proof-of-concept for studying the features of natural sunscreens in the design of simple, safe, efficient, and green sunscreens.


Asunto(s)
Celulosa/metabolismo , Colorantes/efectos adversos , Labio/efectos de la radiación , Nanopartículas/metabolismo , Factor de Protección Solar/métodos , Animales , Humanos , Ratones
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