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1.
Environ Sci Technol ; 58(2): 1010-1021, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-37934921

RESUMEN

Despite the increasing prevalence of atmospheric nanoplastics (NPs), there remains limited research on their phytotoxicity, foliar absorption, and translocation in plants. In this study, we aimed to fill this knowledge gap by investigating the physiological effects of tomato leaves exposed to differently charged NPs and foliar absorption and translocation of NPs. We found that positively charged NPs caused more pronounced physiological effects, including growth inhibition, increased antioxidant enzyme activity, and altered gene expression and metabolite composition and even significantly changed the structure and composition of the phyllosphere microbial community. Also, differently charged NPs exhibited differential foliar absorption and translocation, with the positively charged NPs penetrating more into the leaves and dispersing uniformly within the mesophyll cells. Additionally, NPs absorbed by the leaves were able to translocate to the roots. These findings provide important insights into the interactions between atmospheric NPs and crop plants and demonstrate that NPs' accumulation in crops could negatively impact agricultural production and food safety.


Asunto(s)
Antioxidantes , Microplásticos
2.
Macromol Rapid Commun ; 45(13): e2400022, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38704741

RESUMEN

The preparation of self-healing polyurethane elastomers (PUEs) incorporating dynamic bonds is of considerable practical significance. However, developing a PUE with outstanding mechanical properties and high self-healing efficiency poses a significant challenge. Herein, this work has successfully developed a series of self-healing PUEs with various outstanding properties through rational molecular design. These PUEs incorporate m-xylylene diisocyanate and reversible dimethylglyoxime as hard segment, along with polytetramethylene ether glycol as soft segment. A significant amount of dynamic oxime-carbamate and hydrogen bonds are formed in hard segment. The microphase separated structure of the PUEs enables them to be colorless with a transparency of >90%. Owing to the chemical composition and multiple dynamic interactions, the PUEs are endowed with ultra-high tensile strength of 34.5 MPa, satisfactory toughness of 53.9 MJ m-3, and great elastic recovery both at low and high strains. The movement of polymer molecular chains and the dynamic reversible interactions render a self-healing efficiency of 101% at 70 °C. In addition, this self-healing polyurethane could still maintain high mechanical properties after recycling. This study provides a design strategy for the preparation of a comprehensive polyurethane with superior overall performance, which holds wide application prospects in the fields of flexible displays and solar cells.


Asunto(s)
Carbamatos , Elastómeros , Enlace de Hidrógeno , Oximas , Poliuretanos , Resistencia a la Tracción , Poliuretanos/química , Oximas/química , Elastómeros/química , Carbamatos/química , Estructura Molecular , Elasticidad
3.
Small ; 19(29): e2301693, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37093550

RESUMEN

Endogenous electric field is ubiquitous in a multitude of important living activities such as bone repair, cell signal transduction, and nerve regeneration, signifying that regulating the electric field in organisms is highly beneficial to maintain organism health. As an emerging and promising research direction, piezoelectric nanomedicine and materdicine precisely activated by ultrasound with synergetic advantages of deep tissue penetration, remote spatiotemporal selectivity, and mechanical-electrical energy interconversion, have been progressively utilized for disease treatment and tissue repair by participating in the modulation of endogenous electric field. This specific nanomedicine utilizing piezoelectric effect activated by ultrasound is typically regarded as "sonopiezoelectric nanomedicine". This comprehensive review summarizes and discusses the substantially employed sonopiezoelectric nanomaterials and nanotherapies to provide an insight into the internal mechanism of the corresponding biological behavior/effect of sonopiezoelectric biomaterials in versatile disease treatments. This review primarily focuses on the sonopiezoelectric biomaterials for biosensing, drug delivery, tumor therapy, tissue regeneration, antimicrobia, and further illuminates the underlying sonopiezoelectric mechanism. In addition, the challenges and developments/prospects of sonopiezoelectric nanomedicine are analyzed for promoting the further clinical translation. It is earnestly expected that this kind of nanomedicine/biomaterials-enabled sonopiezoelectric technology will provoke the comprehensive investigation and promote the clinical development of the next-generation multifunctional materdicine.


Asunto(s)
Nanomedicina , Nanoestructuras , Sistemas de Liberación de Medicamentos , Materiales Biocompatibles , Ultrasonografía
4.
J Nanobiotechnology ; 21(1): 300, 2023 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-37633883

RESUMEN

Bacterial infections, especially those caused by drug-resistant bacteria, have seriously threatened human life and health. There is urgent to develop new antibacterial agents to reduce the problem of antibiotics. Biomedical materials with good antimicrobial properties have been widely used in antibacterial applications. Among them, hydrogels have become the focus of research in the field of biomedical materials due to their unique three-dimensional network structure, high hydrophilicity, and good biocompatibility. In this review, the latest research progresses about hydrogels in recent years were summarized, mainly including the preparation methods of hydrogels and their antibacterial applications. According to their different antibacterial mechanisms, several representative antibacterial hydrogels were introduced, such as antibiotics loaded hydrogels, antibiotic-free hydrogels including metal-based hydrogels, antibacterial peptide and antibacterial polymers, stimuli-responsive smart hydrogels, and light-mediated hydrogels. In addition, we also discussed the applications and challenges of antibacterial hydrogels in biomedicine, which are expected to provide new directions and ideas for the application of hydrogels in clinical antibacterial therapy.


Asunto(s)
Antibacterianos , Materiales Biocompatibles , Humanos , Antibacterianos/farmacología , Materiales Biocompatibles/farmacología , Hidrogeles/farmacología , Polímeros/farmacología
5.
Oral Dis ; 2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37103670

RESUMEN

OBJECTIVE: The temporomandibular joint (TMJ) disc cushions intraarticular stress during mandibular movements. While mechanical overloading is related to cartilage degeneration, the pathogenesis of TMJ disc degeneration is unclear. Here, we determined the regulatory role of mechanoinductive transient receptor potential vanilloid 4 (TRPV4) in mechanical overload-induced TMJ disc degeneration. METHODS: We explored the effect of mechanical overload on the TMJ discs in a rat occlusal interference model in vivo, and by applying sustained compressive force in vitro. TRPV4 inhibition was delivered by small interfering RNA or GSK2193874; TRPV4 activation was delivered by GSK1016790A. The protective effect of TRPV4 inhibition was validated in the rat occlusal interference model. RESULTS: Occlusal interference induced TMJ disc degeneration with enhanced extracellular matrix degradation in vivo and mechanical overload promoted inflammatory responses in the TMJ disc cells via Ca2+ influx with significantly upregulated TRPV4. TRPV4 inhibition reversed mechanical overload-induced inflammatory responses; TRPV4 activation simulated mechanical overload-induced inflammatory responses. Moreover, TRPV4 inhibition alleviated TMJ disc degeneration in the rat occlusal interference model. CONCLUSION: Our findings suggest TRPV4 plays a pivotal role in the pathogenesis of mechanical overload-induced TMJ disc degeneration and may be a promising target for the treatment of degenerative changes of the TMJ disc.

6.
J Liposome Res ; 33(4): 338-352, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36974767

RESUMEN

Co-loading doxorubicin (DOX) and Schizandrin A (SchA) long-circulating liposome (SchA-DOX-Lip) have been confirmed to have good antitumor activity in vitro. However, in vivo pharmacodynamics, targeting, safety, and mechanism of action of SchA-DOX-Lip still need to be further verified. We investigated the tumor inhibition effect, targeting, safety evaluation, and regulation of tumor apoptosis-related proteins of the SchA-DOX-Lip. MTT assay was used to investigate the inhibitory effect of SchA-DOX-Lip on CBRH7919 cells. The drug uptake of CBRH7919 cells was observed by inverted fluorescence microscope. The tumor-bearing nude mice models of CBRH7919 were established, and the anti-tumor effect of SchA-DOX-Lip in vivo was evaluated by tumor biological observation, H&E staining, and TUNEL staining. The distribution and targeting of SchA-DOX-Lip in nude mice models were investigated by small animal imaging and tissue distribution experiment of CBRH7919. The biosafety of SchA-DOX-Lip was evaluated by blood routine parameters, biochemical indexes, and H&E staining. The expression of tumor-associated apoptotic proteins (Bcl-2, Bax, and Caspase-3) was detected by immunohistochemistry anvd western blotting. The results showed that SchA-DOX-Lip had cytotoxicity to CBRH7919 cells which effectively inhibited the proliferation of CBRH7919 cells, improved the uptake of drugs by CBRH7919 cells and the targeting effect of drugs on tumor site. H&E staining and biochemical detection results showed that SchA-DOX-Lip had high biosafety and did not cause serious damage to normal tissues. Western-blotting and TUNEL staining results showed that SchA-DOX-Lip could improve the regulatory effect of drugs on tumor apoptosis proteins. It was demonstrated that SchA-DOX-Lip had high safety and strong tumor inhibition effects, providing a new method for the clinical treatment of hepatocellular carcinoma (HCC).


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Ratones , Liposomas/farmacología , Ratones Desnudos , Neoplasias Hepáticas/tratamiento farmacológico , Carcinoma Hepatocelular/tratamiento farmacológico , Doxorrubicina/farmacología , Apoptosis , Línea Celular Tumoral
7.
Sensors (Basel) ; 23(7)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37050777

RESUMEN

Recent advances in flexible pressure sensors have fueled increasing attention as promising technologies with which to realize human epidermal pulse wave monitoring for the early diagnosis and prevention of cardiovascular diseases. However, strict requirements of a single sensor on the arterial position make it difficult to meet the practical application scenarios. Herein, based on three single-electrode sensors with small area, a 3 × 1 flexible pressure sensor array was developed to enable measurement of epidermal pulse waves at different local positions of radial artery. The designed single sensor holds an area of 6 × 6 mm2, which mainly consists of frosted microstructured Ecoflex film and thermoplastic polyurethane (TPU) nanofibers. The Ecoflex film was formed by spinning Ecoflex solution onto a sandpaper surface. Micropatterned TPU nanofibers were prepared on a fluorinated ethylene propylene (FEP) film surface using the electrospinning method. The combination of frosted microstructure and nanofibers provides an increase in the contact separation of the tribopair, which is of great benefit for improving sensor performance. Due to this structure design, the single small-area sensor was characterized by pressure sensitivity of 0.14 V/kPa, a response time of 22 ms, a wide frequency band ranging from 1 to 23 Hz, and stability up to 7000 cycles. Given this output performance, the fabricated sensor can detect subtle physiological signals (e.g., respiration, ballistocardiogram, and heartbeat) and body movement. More importantly, the sensor can be utilized in capturing human epidermal pulse waves with rich details, and the consistency of each cycle in the same measurement is as high as 0.9987. The 3 × 1 flexible sensor array is employed to acquire pulse waves at different local positions of the radial artery. In addition, the time domain parameters including pulse wave transmission time (PTT) and pulse wave velocity (PWV) can be obtained successfully, which holds promising potential in pulse-based cardiovascular system status monitoring.


Asunto(s)
Nanofibras , Poliuretanos , Humanos , Nanofibras/química , Análisis de la Onda del Pulso , Arteria Radial/fisiología
8.
Int J Mol Sci ; 24(14)2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37511385

RESUMEN

Polyurethane (PU) refers to the polymer containing carbamate groups in its molecular structure, generally obtained by the reaction of isocyanate and alcohol. Because of its flexible formulation, diverse product forms, and excellent performance, it has been widely used in mechanical engineering, electronic equipment, biomedical applications, etc. Through physical or chemical methods, ionic groups are introduced into PU, which gives PU electrical conductivity, flame-retardant, and antistatic properties, thus expanding the application fields of PU, especially in flexible devices such as sensors, actuators, and functional membranes for batteries and gas absorption. In this review, we firstly introduced the characteristics of PU in chemical and microphase structures and their related physical and chemical performance. To improve the performance of PU, ionic liquids (ILs) were applied in the processing or synthesis of PU, resulting in a new type of PU called ionic PU. In the following part of this review, we mainly summarized the fabrication methods of IL-modified PUs via physical blending and the chemical copolymerization method. Then, we summarized the research progress of the applications for IL-modified PUs in different fields, including sensors, actuators, transistors, antistatic films, etc. Finally, we discussed the future development trends and challenges faced by IL-modified PUs.


Asunto(s)
Líquidos Iónicos , Poliuretanos , Humanos , Poliuretanos/química , Polímeros , Estructura Molecular , Supuración
9.
Molecules ; 28(12)2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37375125

RESUMEN

Titanium (Ti) and its alloys are widely used in medical treatment, engineering, and other fields because of their excellent properties including biological activity, an elastic modulus similar to that of human bones, and corrosion resistance. However, there are still many defects in the surface properties of Ti in practical applications. For example, the biocompatibility of Ti with bone tissue can be greatly reduced in implants due to a lack of osseointegration as well as antibacterial properties, which may lead to osseointegration failure. To address these problems and to take advantage of the amphoteric polyelectrolyte properties of gelatin, a thin layer of gelatin was prepared by electrostatic self-assembly technology. Diepoxide quaternary ammonium salt (DEQAS) and maleopimaric acid quaternary ammonium salt (MPA-N+) were then synthesized and grafted onto the thin layer. The cell adhesion and migration experiments demonstrated that the coating has excellent biocompatibility, and those grafted with MPA-N+ promoted cell migration. The bacteriostatic experiment showed that the mixed grafting with two ammonium salts had excellent bacteriostatic performance against Escherichia coli and Staphylococcus aureus, with bacteriostasis rates of 98.1 ± 1.0% and 99.2 ± 0.5%, respectively.


Asunto(s)
Compuestos de Amonio , Titanio , Humanos , Titanio/farmacología , Gelatina/farmacología , Antibacterianos/farmacología , Osteogénesis , Oseointegración , Propiedades de Superficie , Compuestos de Amonio/farmacología , Materiales Biocompatibles Revestidos/farmacología
10.
Molecules ; 28(10)2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37241863

RESUMEN

Thin oxide layers form easily on the surfaces of titanium (Ti) components, with thicknesses of <100 nm. These layers have excellent corrosion resistance and good biocompatibility. Ti is susceptible to bacterial development on its surface when used as an implant material, which reduces the biocompatibility between the implant and the bone tissue, resulting in reduced osseointegration. In the present study, Ti specimens were surface-negatively ionized using a hot alkali activation method, after which polylysine and polydopamine layers were deposited on them using a layer-by-layer self-assembly method, then a quaternary ammonium salt (QAS) (EPTAC, DEQAS, MPA-N+) was grafted onto the surface of the coating. In all, 17 such composite coatings were prepared. Against Escherichia coli and Staphylococcus aureus, the bacteriostatic rates of the coated specimens were 97.6 ± 2.0% and 98.4 ± 1.0%, respectively. Thus, this composite coating has the potential to increase the osseointegration and antibacterial performance of implantable Ti devices.


Asunto(s)
Compuestos de Amonio , Titanio , Titanio/farmacología , Polilisina/farmacología , Materiales Biocompatibles Revestidos/farmacología , Antibacterianos/farmacología , Escherichia coli , Propiedades de Superficie
11.
BMC Oral Health ; 23(1): 834, 2023 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-37932699

RESUMEN

BACKGROUND: To assess the impact of coronavirus disease-2019 (COVID-19) in its outbreak stage (Spring Festival in 2020) on oral emergency services. METHODS: Oral emergency cases in Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, during the Spring Festival after the outbreak of the COVID-19 epidemic in 2020 were collected and compared with those in 2018 and 2019. Electronic medical records including the visited department, age, sex, time, date, region, and diagnosis were collected and analyzed. The results were statistically analyzed using Pearson's Chi-square test and one-way analysis of variance (ANOVA). RESULTS: Compared with that in 2018 and 2019, the total number of patients decreased during the Spring Festival in 2020 (p < 0.001), but the proportions of patients visiting Oral Surgery and Oral, Head, and Neck Oncology Emergency departments increased. The average age of patients increased, and the number of night visits decreased. Toothache diseases involving endodontic and periodontal diseases increased, while the proportion of maxillofacial trauma decreased. The wasn't a linear association between diagnosis or genders (P > 0.001) across years. However, a linear-by-linear association between age groups and years, visited departments and years were observed (P < 0.001). CONCLUSIONS: The study revealed that the transmission of COVID-19 affected the patient population and structure of disease types and oral services in 2020 during the Spring Festival, compared with those in the previous two years. The visits to oral emergency departments and the proportions of patients who were children and adolescents reduced; meanwhile, the percentage of the elderly people increased during the outbreak of COVID-19. The clear trend of age groups and visiting divisions could be used as a marker to reflect the severity of the COVID-19 pandemic. These results may serve as a reference for dental practitioners involved in oral emergency services and to allocate the limited emergency health resources.


Asunto(s)
COVID-19 , Niño , Adolescente , Humanos , Masculino , Femenino , Anciano , Estudios Retrospectivos , Pandemias , Odontólogos , China/epidemiología , Rol Profesional
12.
Molecules ; 27(18)2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36144588

RESUMEN

Phycocyanin is a blue fluorescent protein with multi-bioactive functions. However, the multi-bioactivities and spectral stability of phycocyanin are susceptible to external environmental conditions, which limit its wide application. Here, the structure, properties, and biological activity of phycocyanin were discussed. This review highlights the significance of the microcapsules' wall materials which commonly protect phycocyanin from environmental interference and summarizes the current preparation principles and characteristics of microcapsules in food and pharma industries, including spray drying, electrospinning, electrospraying, liposome delivery, sharp-hole coagulation baths, and ion gelation. Moreover, the major technical challenge and corresponding countermeasures of phycocyanin microencapsulation are also appraised, providing insights for the broader application of phycocyanin.


Asunto(s)
Liposomas , Ficocianina , Cápsulas/química
13.
Langmuir ; 37(28): 8474-8485, 2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-34236863

RESUMEN

Protein stability and performance in various natural and artificial systems incorporating many other macromolecules for therapeutic, diagnostic, sensor, and biotechnological applications attract increasing interest with the expansion of these technologies. Here we address the catalytic activity of lysozyme protein (LYZ) in the presence of a polyethylene glycol (PEG) crowder in a broad range of concentrations and temperatures in aqueous solutions of two different molecular mass PEG samples (Mw = 3350 and 10000 g/mol). The phase behavior of PEG-protein solutions is examined by using dynamic light scattering (DLS) and small-angle X-ray scattering (SAXS), while the enzyme denaturing is monitored by using an activity assay (AS) and circular dichroism (CD) spectroscopy. Molecular dynamic (MD) simulations are used to illustrate the effect of PEG concentration on protein stability at high temperatures. The results demonstrate that LYZ residual activity after 1 h incubation at 80 °C is improved from 15% up to 55% with the addition of PEG. The improvement is attributed to two underlying mechanisms. (i) Primarily, the stabilizing effect is due to the suppression of the enzyme aggregation because of the stronger PEG-protein interactions caused by the increased hydrophobicity of PEG and lysozyme at elevated temperatures. (ii) The MD simulations showed that the addition of PEG to some degree stabilizes the secondary structures of the enzyme by delaying unfolding at elevated temperatures. The more pronounced effect is observed with an increase in PEG concentration. This trend is consistent with CD and AS experimental results, where the thermal stability is strengthened with increasing of PEG concentration and molecular mass. The results show that the highest stabilizing effect is approached at the critical overlap concentration of PEG.


Asunto(s)
Polietilenglicoles , Estabilidad de Enzimas , Peso Molecular , Estabilidad Proteica , Dispersión del Ángulo Pequeño , Difracción de Rayos X
14.
BMC Public Health ; 21(1): 374, 2021 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-33596869

RESUMEN

BACKGROUND: Hand, foot and mouth disease (HFMD) is one of the common intestinal infectious diseases worldwide and has caused huge economic and disease burdens in many countries. The average annual incidence rate of HFMD was 11.66% in Shaanxi during the time span from 2009 to 2018. There are distinct differences within Shaanxi, as it is a special region that crosses three temperature zones. Hence, in this study, a spatiotemporal analysis of Shaanxi was performed to reveal the characteristics of the distribution of HFMD and to explore the meteorological determinants of HFMD. METHODS: The county-level and municipal data from Shaanxi Province from 2009 to 2018 were applied to research the spatiotemporal characteristics of HFMD and its meteorological determinants. Time series and spatial autocorrelation analyses were applied to assess the spatiotemporal characteristics of HFMD. This study used spatial econometric panel models to explore the relationship between HFMD and meteorological factors based on the data of 107 counties and 10 municipalities. RESULTS: The incidence rate of HFMD displayed no variable trend throughout the whole research period. A high incidence rate of HFMD was observed from June to September, corresponding to a time when the climate is characterized by heavy rain, high temperature, and high humidity. The high-incidence areas were mainly located in the central region in Shaanxi, whereas the low-incidence spots were mainly found in Northern Shaanxi. Regarding the meteorological factors analysed in this study, in general, the incidence rate of HFMD in specific regions was positively associated with the rainfall, temperature and humidity. CONCLUSION: These results could be applied by the government and the general public to take effective measures to prevent disease. Region-targeted policies could be enacted and implemented in the future according to specific situations in different areas and the relevant meteorological determinants. Additionally, meteorological conditions normally extend to a wide-ranging region; thus, cooperation among surrounding regions is necessary.


Asunto(s)
Enfermedad de Boca, Mano y Pie , China/epidemiología , Ciudades , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Incidencia , Conceptos Meteorológicos , Análisis Espacio-Temporal , Temperatura
15.
Molecules ; 26(2)2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33451119

RESUMEN

Subcritical water treatment has received considerable attention due to its cost effectiveness and environmentally friendly properties. In this investigation, Chinese quince fruits were submitted to subcritical water treatment (130, 150, and 170 °C), and the influence of treatments on the structure of milled wood lignin (MWL) was evaluated. Structural properties of these lignin samples (UL, L130, L150, and L170) were investigated by high-performance anion exchange chromatography (HPAEC), FT-IR, gel permeation chromatography (GPC), TGA, pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), 2D-Heteronculear Single Quantum Coherence (HSQC) -NMR, and 31P-NMR. The carbohydrate analysis showed that xylose in the samples increased significantly with higher temperature, and according to molecular weight and thermal analysis, the MWLs of the pretreated residues have higher thermal stability with increased molecular weight. The spectra of 2D-NMR and 31P-NMR demonstrated that the chemical linkages in the MWLs were mainly ß-O-4' ether bonds, ß-5' and ß-ß', and the units were principally G- S- H- type with small amounts of ferulic acids; these results are consistent with the results of Py-GC/MS analysis. It is believed that understanding the structural changes in MWL caused by subcritical water treatment will contribute to understanding the mechanism of subcritical water extraction, which in turn will provide a theoretical basis for developing the technology of subcritical water extraction.


Asunto(s)
Frutas/química , Lignina/química , Rosaceae/química , Purificación del Agua , Madera/química , China , Estructura Molecular , Tamaño de la Partícula
16.
AAPS PharmSciTech ; 23(1): 6, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34851496

RESUMEN

Currently, bacterial conjunctivitis is managed by multiple antibiotic eye-drop solution, which is highly inefficient due to low ocular bioavailability and frequent dosing. Therapeutic soft contact lenses can be used to sustain the release of ocular drugs. However, the conventional soaking method (economic and widely used) showed low drug uptake and high burst release, and the optophysical properties of the contact lens were altered for clinical application. In this paper, novel ofloxacin-loaded niosomes were developed to increase the drug loading capacity of contact lenses while also sustaining ocular drug delivery. Ofloxacin-loaded niosomes were prepared by the thin film hydration technique with three levels of cholesterol. The niosome-laden contact lenses (OFL-Nio-L) led to improved optophysical properties (swelling, transmittance, oxygen permeability) and lysozyme adherence compared to the conventional soaked contact lens (CV-OFL-L). The in vitro drug release data of CV-OFL-L showed high burst release, while OFL-Nio-L lenses showed sustained release up to 48-96 h. In a rabbit tear fluid model, the OFL-Nio-100-L lens showed a high drug concentration at all-time points compared to the CV-OFL-L and eye-drop solution. The efficacy study in the rabbit model showed improved healing effect with OFL-Nio-100-L lens compared to frequent eye-drop therapy. In conclusion, the paper demonstrated the successful application of niosomes to deliver ofloxacin using contact lens without affecting the critical lens properties to substitute eye-drop therapy.


Asunto(s)
Lentes de Contacto Hidrofílicos , Liposomas , Animales , Materiales Biocompatibles , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Ofloxacino , Conejos
17.
AAPS PharmSciTech ; 22(1): 46, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33442785

RESUMEN

Combination therapy is one of the most common clinical practices in the treatment of malignancies. Synergistic effects, however, are produced only when optimal ratios of combined drugs were delivered to tumor cells. Thus, carriers co-encapsulating of multiple drugs are widely utilized for coordinated delivery. Herein, co-encapsulated pegylated liposomal formulation of mitoxantrone (MIT) and berberine (BER) at an optimal ratio has been developed (MBL) with high encapsulation efficiency (EE) and drug loading in order to achieve the purpose of ratiometric loading and delivery. MBL can not only extend blood circulation but also enhance tumor accumulation for both MIT and BER. More importantly, MBL can maintain the originally desired drug ratio in tumors within 48 h of intravenous injection for synergistic therapy. Compared with the liposomal formulation of MIT-treated group (ML), the progression of tumor growth was inhibited significantly in murine 4T1 breast tumor model after the treatment of MBL, as well as a lower cardiac toxicity. In addition, MBL evidently prolonged the survival of mice with L1210 ascitic tumor model. In summary, such a strategy of co-encapsulated liposomes could improve the clinical applications against multiple cancers.


Asunto(s)
Antineoplásicos/administración & dosificación , Berberina/administración & dosificación , Cardiotoxicidad/prevención & control , Corazón/efectos de los fármacos , Liposomas , Mitoxantrona/administración & dosificación , Animales , Antineoplásicos/toxicidad , Berberina/farmacología , Línea Celular Tumoral , Femenino , Humanos , Ratones , Mitoxantrona/toxicidad
18.
Bioconjug Chem ; 31(1): 37-42, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31815437

RESUMEN

Nucleic acid aptamers, also known as "chemical antibodies", have been widely employed in targeted cancer therapy and diagnosis. For example, aptamer-drug conjugates (ApDCs), through covalent conjugation of cytotoxic warheads to aptamers, have demonstrated anticancer efficacy both in vitro and in vivo. However, a general strategy to endow ApDCs with enhanced biostability, prolonged circulation half-life, and high drug loading content remained elusive. Herein, we present a polymeric approach to engineer ApDCs via conjugation of cell-targeting aptamers with water-soluble polyprodrugs containing a reductive environmentally sensitive prodrug and biocompatible brush-like backbone. The resultant high-drug loading Aptamer-PolyproDrug Conjugates (ApPDCs) exhibited high nuclease resistance, extended in vivo circulation time, specific recognition, and cellular uptake to target cells, reduction-triggered and fluorescent-reporting drug release, and effective cytotoxicity. We could also further expand this design principle toward combination therapy by using two kinds of therapeutic drugs with distinct pharmacological mechanisms.


Asunto(s)
Antineoplásicos/administración & dosificación , Aptámeros de Nucleótidos/química , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Neoplasias/tratamiento farmacológico , Polímeros/química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Línea Celular Tumoral , Liberación de Fármacos , Humanos
19.
Cochrane Database Syst Rev ; 5: CD006126, 2020 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-32408387

RESUMEN

BACKGROUND: Retinal detachment (RD) with proliferative vitreoretinopathy (PVR) often requires surgery to restore normal anatomy and to stabilize or improve vision. PVR usually occurs in association with recurrent RD (that is, after initial retinal re-attachment surgery), but occasionally may be associated with primary RD. Either way, for both circumstances a tamponade agent (gas or silicone oil) is needed during surgery to reduce the rate of postoperative recurrent RD. OBJECTIVES: The objective of this review was to assess the relative safety and effectiveness of various tamponade agents used with surgery for RD complicated by PVR. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (the Cochrane Library 2019, Issue 1), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to January 2019), Embase (January 1980 to January 2019), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to January 2019), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 2 January 2019. SELECTION CRITERIA: We included randomized controlled trials (RCTs) on participants undergoing surgery for RD associated with PVR that compared various tamponade agents. DATA COLLECTION AND ANALYSIS: Two review authors screened the search results independently. We used the standard methodological procedures expected by Cochrane. MAIN RESULTS: We identified four RCTs (601 participants) that provided data for the primary and secondary outcomes. Three RCTs provided data on visual acuity, two reported on macular attachment, one on retinal reattachment and another two on adverse events such as RD, worsening visual acuity and intraocular pressure. Study Characteristics Participants' characteristics varied across studies and across intervention groups, with an age range between 21 to 89 years, and were predominantly men. The Silicone Study was conducted in the USA and consisted of two RCTs: (silicone oil versus sulfur hexafluoride (SF6) gas tamponades; 151 participants) and (silicone oil versus perfluropropane (C3F8) gas tamponades; 271 participants). The third RCT compared heavy silicone oil (a mixture of perfluorohexyloctane (F6H8) and silicone oil) with standard silicone oil (either 1000 centistokes or 5000 centistokes; 94 participants). The fourth RCT compared 1000 centistokes with 5000 centistokes silicone oil in 85 participants. We assessed most RCTs at low or unclear risk of bias for most 'Risk of bias' domains. Findings Although SF6 gas was reported to be associated with worse anatomic and visual outcomes than was silicone oil at one year (quantitative data not reported), at two years, silicone oil compared to SF6 gas showed no evidence of a difference in visual acuity (33% versus 51%; risk ratio (RR) 1.57; 95% confidence interval (CI) 0.93 to 2.66; 1 RCT, 87 participants; low-certainty evidence). At one year, another RCT comparing silicone oil and C3F8 gas found no evidence of a difference in visual acuity between the two groups (41% versus 39%; RR 0.97; 95% CI 0.73 to 1.31; 1 RCT, 264 participants; low-certainty evidence). In a third RCT, participants treated with standard silicone oil compared to those receiving heavy silicone oil also showed no evidence of a difference in the change in visual acuity at one year, measured on logMAR scale ( mean difference -0.03 logMAR; 95% CI -0.35 to 0.29; 1 RCT; 93 participants; low-certainty evidence). The fourth RCT with 5000-centistoke and 1000-centistoke comparisons did not report data on visual acuity. For macular attachment, participants treated with silicone oil may probably experience more favorable outcomes than did participants who received SF6 at both one year (quantitative data not reported) and two years (58% versus 79%; RR 1.37; 95% CI 1.01 to 1.86; 1 RCT; 87 participants; low-certainty evidence). In another RCT, silicone oil compared to C3F8 at one year found no evidence of difference in macular attachment (RR 1.00; 95% CI 0.86 to 1.15; 1 RCT, 264 participants; low-certainty evidence). One RCT that compared 5000 centistokes to 1000 centistoke reported that retinal reattachment was successful in 67 participants (78.8%) with first surgery and 79 participants (92.9%) with the second surgery, and no evidence of between-group difference (1 RCT; 85 participants; low-certainty evidence). The fourth RCT that compared standard silicone oil with heavy silicone oil did not report on macular attachment. Adverse events In one RCT (86 participants), those receiving standard 1000 centistoke silicone oil compared with those of the 5000 centistoke silicone oil showed no evidence of a difference in intraocular pressure elevation at 18 months (24% versus 22%; RR 0.90; 95% CI 0.41 to 1.94; low-certainty evidence), visually significant cataract (49% versus 64%; RR 1.30; 95% CI 0.89 to 1.89; low-certainty evidence), and incidence of retina detachment after the removal of silicone oil (RR 0.36 95% CI 0.08 to 1.67; low-certainty evidence). Another RCT that compared standard silicone oil with heavy silicone oil suggests no difference in retinal detachment at one year (25% versus 22%; RR 0.89; 95% CI 0.54 to 1.48; 1 RCT; 186 participants; low-certainty evidence). Retinal detachment was not reported in the RCTs that compared silicone oil versus SF6 and silicone oil versus to C3F8. AUTHORS' CONCLUSIONS: There do not appear to be any major differences in outcomes between C3F8 and silicone oil. Silicone oil may be better than SF6 for macular attachment and other short-term outcomes. The choice of a tamponade agent should be individualized for each patient. The use of either C3F8 or standard silicone oil appears reasonable for most patients with RD associated with PVR. Heavy silicone oil, which is not available for routine clinical use in the USA, may not demonstrate evidence of superiority over standard silicone oil.


Asunto(s)
Fluorocarburos/administración & dosificación , Desprendimiento de Retina/terapia , Aceites de Silicona/administración & dosificación , Hexafluoruro de Azufre/administración & dosificación , Vitreorretinopatía Proliferativa/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Presión Intraocular , Mácula Lútea , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Desprendimiento de Retina/etiología , Desprendimiento de Retina/prevención & control , Prevención Secundaria , Agudeza Visual , Adulto Joven
20.
Ecotoxicol Environ Saf ; 188: 109858, 2020 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-31706236

RESUMEN

Cultivar-dependent cadmium (Cd) accumulation was principal in developing Cd-pollution safe cultivars (PSCs). Proteins related to different Cd accumulations of the low-Cd-accumulating (SJ19) and high-Cd-accumulating (CX4) cultivars were investigated by iTRAQ analysis. Higher Cd bioaccumulation factors and translocation factor in CX4 than in SJ19 were consistent with the cultivar-dependent Cd accumulations. The Cd uptake was promoted in CX4 due to its higher expression of Cd-binding proteins and the lower expression of Cd-efflux proteins in roots. What's more, significantly elevated thiol groups (PC2 and PC3) in CX4 under Cd stress might contribute to the high Cd accumulation in roots and the root-to-shoot translocation of Cd-PC complex. Up-regulated proteins involved in cellulose biosynthesis and pectin de-esterification in SJ19 enhanced the Cd sequestration of root cell walls, which was considered as the predominant strategy for reducing Cd accumulation in shoots. The present study provided novel insights in the cultivar-dependent Cd accumulation in shoots of B. parachinensis.


Asunto(s)
Brassica/metabolismo , Cadmio/metabolismo , Proteínas de Plantas/metabolismo , Contaminantes del Suelo/metabolismo , Transporte Biológico , Brassica/genética , Celulosa/metabolismo , Pectinas/metabolismo , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Proteómica , Reactivos de Sulfhidrilo/metabolismo
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