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3.
J Dent (Shiraz) ; 23(3): 272-277, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36506884

RESUMEN

Statement of the Problem: The success of root canal therapy depends on root canal irrigation, disinfection, and sealing of root canal. Wettability and roughness of root dentine surface are important factors in root canal disinfection and sealing. Purpose: This study aimed to assess the effect of chloroform application on roughness and wettability of the root canal walls in endodontic retreatment. Materials and Method: This in vitro experimental study evaluated 70 sound extracted human anterior teeth. The specimens were then randomly assigned to 7 groups as follows: Chloroform (group 1), 1g gutta percha+chloroform (group 2), 2g gutta percha+ chloroform (group 3), 1g gutta percha+ 1g sealer+ chloroform (group 4), 2g gutta perch+ 2g sealer+chloroform (group 5), 1g sealer + chloroform (group 6) and 2g sealer + chloroform (group 7). One drop of distilled water was placed on each tooth to measure the contact angle and wettability. Photographs were obtained of an area measuring 50×50 µm2 in three directions under an atomic force microscope to measure the roughness. The tooth blocks were exposed to the abovementioned mixtures for 10 min, and then rinsed with saline. The roughness and wettability of each sample were measured before and after treatment. Data was analyzed using one-way ANOVA and Tukey's test. Results: The roughness of all groups significantly decreased following treatment, except for groups 1 and 4. The contact angle increased in all groups after treatment (except for the chloroform group), which indicated decreased wettability. The roughness and the contact angle have shown no correlation. Conclusion: Application of chloroform for removal of gutta-percha and sealer in endodontic retreatment decreases the roughness and wettability of dentine.

4.
Artículo en Inglés | MEDLINE | ID: mdl-36176584

RESUMEN

Low surface energy and hydrophobicity of polymethyl methactylate (PMMA) are the main disadvantages of this biomaterial. The aim of this study was to investigate the effects of a new coating process on the surface characteristics and properties of PMMA. A combination of temperature and pressure was used for deposition of titanium dioxide (TiO2) on the surface of PMMA. The PMMA coated with TiO2 thin films and prepared by sputtering and non-coated PMMA were considered as control groups. The surface wettability, functional group, and roughness were determined by contact angle measurement, Fourier transform Infrared spectroscopy (FTIR), and 3D laser scanning digital microscopy, respectively. The flexural strength of coated and non-coated samples was measured using three-point bending test. The cell proliferation, attachment, and viability were determined using 3-(4,5-dimethyldiazol-2-yl)-2,5-diphenyl tetrazolium bromide, live and dead assay, scanning electron microscope (SEM), and DAPI (4',6-diamidino-2-phenylindole) staining. The antifungal activity of TiO2 was also determined by examining the biofilm attachment of Candida albicans. The obtained results showed that TiO2 was successfully coated on PMMA. The contact angle measurement shows a significant increase of hydrophilicity in TiO2-coated PMMA. FTIR and roughness analysis revealed no loss of TiO2 from coated specimens following sonication. The cell viability after 7 days culturing on TiO2-coated specimens was more than the cell viability on the control groups. SEM images and DAPI staining showed that the total number of the cells increased after 7 days of seeding on TiO2-coated group, whereas it decreased gradually in both control groups. C. albicans attachment also decreased by 63% to 77% on the coated PMMA surface. Overall, this research suggested a new way for developing surface energy of PMMAs for biomedical applications.

5.
Crit Rev Food Sci Nutr ; 62(13): 3658-3697, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33399020

RESUMEN

The therapeutic effects of carotenoids as dietary supplements to control or even treat some specific diseases including diabetic retinopathy, cardiovascular diseases, bacterial infections, as well as breast, prostate, and skin cancer are discussed in this review and also thoughts on future research for their widespread use are emphasized. From the stability standpoint, carotenoids have low bioavailability and bioaccessibility owing to their poor water solubility, deterioration in the presence of environmental stresses such as oxygen, light, and high heat as well as rapid degradation during digestion. Nanoencapsulation technologies as wall or encapsulation materials have been increasingly used for improving food product functionality. Nanoencapsulation is a versatile process employed for the protection, entrapment, and the delivery of food bioactive products including carotenoids from diverse environmental conditions for extended shelf lives and for providing controlled release. Therefore, we present here, recent (mostly during the last five years) nanoencapsulation methods of carotenoids with various nanocarriers. To us, this review can be considered as the first highlighting not only the potential therapeutic effects of carotenoids on various diseases but also their most effective nanodelivery systems.HighlightsBioactive compounds are of deep interest to improve food properties.Carotenoids (such as ß-carotene and xanthophylls) play indispensable roles in maintaining human health and well-being.A substantial research effort has been carried out on developing beneficial nanodelivery systems for various carotenoids.Nanoencapsulation of carotenoids can enhance their functional properties.Stable nanoencapsulated carotenoids could be utilized in food products.


Asunto(s)
Carotenoides , Sistema de Administración de Fármacos con Nanopartículas , Disponibilidad Biológica , Suplementos Dietéticos , Excipientes , Humanos
6.
J Nanostructure Chem ; 12(5): 919-932, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34580605

RESUMEN

There have been numerous advancements in the early diagnosis, detection, and treatment of genetic diseases. In this regard, CRISPR technology is promising to treat some types of genetic issues. In this study, the relationship between calcium (due to its considerable physicochemical properties) and chitosan (as a natural linear polysaccharide) was investigated and optimized for pCRISPR delivery. To achieve this, different forms of calcium, such as calcium nanoparticles (CaNPs), calcium phosphate (CaP), a binary blend of calcium and chitosan including CaNPs/Chitosan and CaP/Chitosan, as well as their tertiary blend including CaNPs-CaP/Chitosan, were prepared via both routine and green procedures using Salvia hispanica to reduce toxicity and increase nanoparticle stability (with a yield of 85%). Such materials were also applied to the human embryonic kidney (HEK-293) cell line for pCRISPR delivery. The results were optimized using different characterization techniques demonstrating acceptable binding with DNA (for both CaNPs/Chitosan and CaNPs-CaP/Chitosan) significantly enhancing green fluorescent protein (EGFP) (about 25% for CaP/Chitosan and more than 14% for CaNPs-CaP/Chitosan). Supplementary Information: The online version contains supplementary material available at 10.1007/s40097-021-00446-1.

7.
Antibiotics (Basel) ; 10(4)2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-33924304

RESUMEN

Biofilms play a crucial role in the development of Candida-associated denture stomatitis. Inhibition of microbial adhesion to poly(methyl methacrylate) (PMMA) and phosphate containing PMMA has been examined in this work. C. albicans and mixed salivary microbial biofilms were compared on naked and salivary pre-conditioned PMMA surfaces in the presence or absence of antimicrobials (Cetylpyridinium chloride [CPC], KSL-W, Histatin 5 [His 5]). Polymers with varying amounts of phosphate (0-25%) were tested using four C. albicans oral isolates as well as mixed salivary bacteria and 24 h biofilms were assessed for metabolic activity and confirmed using Live/Dead staining and confocal microscopy. Biofilm metabolism was reduced as phosphate density increased (15%: p = 0.004; 25%: p = 0.001). Loading of CPC on 15% phosphated disks showed a substantial decrease (p = 0.001) in biofilm metabolism in the presence or absence of a salivary pellicle. Salivary pellicle on uncharged PMMA enhanced the antimicrobial activity of CPC only. CPC also demonstrated remarkable antimicrobial activity on mixed salivary bacterial biofilms under different conditions displaying the potent efficacy of CPC (350 µg/mL) when combined with an artificial protein pellicle (Biotene half strength).

8.
Biology (Basel) ; 10(3)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652630

RESUMEN

Cancer is one of the most common causes of mortality, and its various treatment methods can have many challenges for patients. As one of the most widely used cancer treatments, chemotherapy may result in diverse side effects. The lack of targeted drug delivery to tumor tissues can raise the possibility of damage to healthy tissues, with attendant dysfunction. In the present study, an optimum formulation of curcumin-loaded niosomes with a calcium alginate shell (AL-NioC) was developed and optimized by a three-level Box-Behnken design-in terms of dimension and drug loading efficiency. The niosomes were characterized by transmission electron microscopy, Fourier-transform infrared spectroscopy, and dynamic light scattering. The as-formulated niosomes showed excellent stability for up to 1 month at 4 °C. Additionally, the niosomal formulation demonstrated a pH-dependent release; a slow-release profile in physiological pH (7.4), and a more significant release rate at acidic conditions (pH = 3). Cytotoxicity studies showed high compatibility of AL-NioC toward normal MCF10A cells, while significant toxicity was observed in MDA-MB-231 and SKBR3 breast cancer cells. Gene expression studies of the cancer cells showed downregulation of Bcl2, cyclin D, and cyclin E genes, as well as upregulation of P53, Bax, caspase-3, and caspase-9 genes expression following the designed treatment. Flow cytometry studies confirmed a significant enhancement in the apoptosis rate in the presence of AL-NioC in both MDA-MB-231 and SKBR3 cells as compared to other samples. In general, the results of this study demonstrated that-thanks to its biocompatibility toward normal cells-the AL-NioC formulation can efficiently deliver hydrophobic drugs to target cancer cells while reducing side effects.

9.
Restor Dent Endod ; 45(4): e45, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33294410

RESUMEN

OBJECTIVE: The aim of this study was to introduce a gelatin/bovine serum albumin (BSA) tissue standard, which provides dissolution properties identical to those of biological tissues. Further, the study evaluated whether the utilization of endodontic activating devices led to enhanced phantom dissolution rates. MATERIALS AND METHODS: Bovine pulp tissue was obtained to determine a benchmark of tissue dissolution. The surface area and mass of samples were held constant while the ratio of gelatin and BSA were varied, ranging from 7.5% to 10% gelatin and 5% BSA. Each sample was placed in an individual test tube that was filled with an appropriate sodium hypochlorite solution for 1, 3, and 5 minutes, and then removed from the solution, blotted dry, and weighed again. The remaining tissue was calculated as the percent of initial tissue to determine the tissue dissolution rate. A radiopaque agent (sodium diatrizoate) and a fluorescent dye (methylene blue) were added to the phantom to allow easy quantification of phantom dissolution in a canal block model when activated using ultrasonic (EndoUltra) or sonic (EndoActivator) energy. RESULTS: The 9% gelatin + 5% BSA phantom showed statistically equivalent dissolution to bovine pulp tissue at all time intervals. Furthermore, the EndoUltra yielded significantly more phantom dissolution in the canal block than the EndoActivator or syringe irrigation. CONCLUSIONS: Our phantom is comparable to biological tissue in terms of tissue dissolution and could be utilized for in vitro tests due to its injectability and detectability.

10.
J Biomed Nanotechnol ; 16(4): 456-466, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32970978

RESUMEN

Among different forms of metallic nanoparticles (NPs), zinc oxide (ZnO) NPs with a very special bandgap of 3.37 eV and considerable binding energy of excitation (60 meV at room temperature), have been classified as high-tech nanoparticles. This study aimed to synthesize ZnO NPs using the extract from Salvia hispanica leaves. The synthesized nanoparticles were fully characterized and the photocatalytic activity was evaluated through the degradation of methylene blue. Additionally, the potential in vitro biological activities of such ZnO NPs in terms of their antibacterial activity were determined, as well as their antioxidant (30 minutes), antiviral (48 hours) and mammalian cell viability properties (48 and 72 hours). This study is the first investigation into the synthesis of such green ZnO NPs mediated by this plant extract, in which both photocatalytic and biomedical properties were found to be promising. The IC50 values for the antibacterial activities were found to be around 17.4 µg mL-1 and 28.5 µg mL-1 for S. aureus and E. coli, respectively, and the antioxidant activity was comparable with the standard BHT. However, the H1N1 inhibition rate using the present green ZnO NPs was lower than oseltamivir (up to about 40% for ZnO NPs and above 90% for oseltamivir) which was expected since it is a drug, but was higher than many synthetic nanoparticles reported in the literature. In addition, the mammalian cell viability assay showed a higher than 80% cellular viability in the presence of 5, 10 and 20 µg mL-1 nanoparticles, and showed a higher than 50% cellular viability in the presence of 50 and 75 µg mL-1 nanoparticles. In this manner, this study showed that these green ZnO NPs should be studied for a wide range of medical applications.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Nanopartículas del Metal , Salvia , Animales , Antibacterianos/farmacología , Antioxidantes/farmacología , Supervivencia Celular , Escherichia coli , Tecnología Química Verde , Mamíferos , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Difracción de Rayos X , Óxido de Zinc/farmacología
11.
Int J Nanomedicine ; 15: 4237-4256, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32606675

RESUMEN

With the passage of time and more advanced societies, there is a greater emergence and incidence of disease and necessity for improved treatments. In this respect, nowadays, aptamers, with their better efficiency at diagnosing and treating diseases than antibodies, are at the center of attention. Here, in this review, we first investigate aptamer function in various fields (such as the detection and remedy of pathogens, modification of nanoparticles, antibiotic delivery and gene delivery). Then, we present aptamer-conjugated nanocomplexes as the main and efficient factor in gene delivery. Finally, we focus on the targeted co-delivery of genes and drugs by nanocomplexes, as a new exciting approach for cancer treatment in the decades ahead to meet our growing societal needs.


Asunto(s)
Antibacterianos/farmacología , Aptámeros de Nucleótidos/química , Técnicas de Transferencia de Gen , Nanopartículas/química , Sistemas de Liberación de Medicamentos , Humanos , Nanopartículas/ultraestructura , Polietileneimina/química
12.
Int J Nanomedicine ; 15: 4363-4392, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32606683

RESUMEN

With continual rapid developments in the biomedical field and understanding of the important mechanisms and pharmacokinetics of biological molecules, controlled drug delivery systems (CDDSs) have been at the forefront over conventional drug delivery systems. Over the past several years, scientists have placed boundless energy and time into exploiting a wide variety of excipients, particularly diverse polymers, both natural and synthetic. More recently, the development of nano polymer blends has achieved noteworthy attention due to their amazing properties, such as biocompatibility, biodegradability and more importantly, their pivotal role in controlled and sustained drug release in vitro and in vivo. These compounds come with a number of effective benefits for improving problems of targeted or controlled drug and gene delivery systems; thus, they have been extensively used in medical and pharmaceutical applications. Additionally, they are quite attractive for wound dressings, textiles, tissue engineering, and biomedical prostheses. In this sense, some important and workable natural polymers (namely, chitosan (CS), starch and cellulose) and some applicable synthetic ones (such as poly-lactic-co-glycolic acid (PLGA), poly(lactic acid) (PLA) and poly-glycolic acid (PGA)) have played an indispensable role over the last two decades for their therapeutic effects owing to their appealing and renewable biological properties. According to our data, this is the first review article highlighting CDDSs composed of diverse natural and synthetic nano biopolymers, blended for biological purposes, mostly over the past five years; other reviews have just briefly mentioned the use of such blended polymers. We, additionally, try to make comparisons between various nano blending systems in terms of improved sustained and controlled drug release behavior.


Asunto(s)
Preparaciones de Acción Retardada/farmacología , Nanopartículas/química , Polímeros/química , Sistemas de Liberación de Medicamentos , Hidrogeles/química
13.
Dent Mater ; 36(2): e47-e58, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31791734

RESUMEN

OBJECTIVES: The purpose of this review is to describe recent developments in pulp tissue engineering using scaffolds and/or stem cells. It is crucial to understand how this approach can revitalize damaged dentin-pulp tissue. Widespread scaffold materials, both natural and synthetic, and their fabrication methods, and stem-progenitor cells with the potential of pulp regeneration will be discussed. DATA AND SOURCES: A review of literature was conducted through online databases, including MEDLINE by using the PubMed search engine, Scopus, and the Cochrane Library. STUDY SELECTION: Studies were selected based on relevance, with a preference given to recent research, particularly from the past decade. CONCLUSIONS: The use of biomaterial scaffolds and stem cells can be safe and potent for the regeneration of pulp tissue and re-establishment of tooth vitality. Natural and synthetic polymers have distinct advantages and limitations and in vitro and in vivo testing have produced positive results for cell attachment, proliferation, and angiogenesis. The type of biomaterial used for scaffold fabrication also facilitates stem cell differentiation into odontoblasts and the resulting biochemistry of tissue repair for each polymer and cell type was discussed. Multiple methods of scaffold design exist for pulp tissue engineering, which demonstrates the variability in tissue engineering applications in endodontics. This review explains the potential of evidence-based tissue engineering strategies and outcomes in pulp regeneration.


Asunto(s)
Pulpa Dental , Ingeniería de Tejidos , Odontoblastos , Polímeros , Regeneración , Andamios del Tejido
14.
Biomaterials ; 232: 119707, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31874428

RESUMEN

Porphyrins are organic compounds that continue to attract much theoretical interest, and have been called the "pigments of life". They have a wide role in photodynamic and sonodynamic therapy, along with uses in magnetic resonance, fluorescence and photoacoustic imaging. There is a vast range of porphyrins that have been isolated or designed, but few of them have real clinical applications. Due to the hydrophobic properties of porphyrins, and their tendency to aggregate by stacking of the planar molecules they are difficult to work with in aqueous media. Therefore encapsulating them in nanoparticles (NPs) or attachment to various delivery vehicles have been used to improve delivery characteristics. Porphyrins can be used in a composite designed material with properties that allow specific targeting, immune tolerance, extended tissue lifetime and improved hydrophilicity. Drug delivery, healing and repairing of damaged organs, and cancer theranostics are some of the medical uses of porphyrin-based nanocomposites covered in this review.


Asunto(s)
Nanopartículas del Metal , Nanocompuestos , Nanopartículas , Fotoquimioterapia , Porfirinas , Animales , Oro , Ratones , Ratones Desnudos , Nanomedicina Teranóstica , Distribución Tisular
15.
Biomed Microdevices ; 21(4): 93, 2019 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-31686232

RESUMEN

Microfluidic systems (MFS) provide a range of advantages in biomedical applications, including improved controllability of material characteristics and lower consumption of reagents, energy, time and money. Fabrication of MFS employs various materials, such as glass, silicon, ceramics, paper, and metals such as gold, copper, aluminum, chromium and titanium. In this review, gold thin film microfluidic channels (GTFMFC) are discussed with reference to fabrication methods and their diverse use in chemical and biomedical applications. The advantages of gold thin films (GTF) include flexibility, ease of manufacture, adhesion to polymer surfaces, chemical stability, good electrical conductivity, surface plasmon resonance effects, ability to be chemically functionalized, etc. Various electroactuators and electroanalytical devices can incorporate GTF. GTF-based MFS have been used in environmental monitoring, assays of biomarkers, immunoassays, cell culture studies and pathogen identification.


Asunto(s)
Investigación Biomédica/instrumentación , Oro/química , Dispositivos Laboratorio en un Chip
16.
Acta Biomater ; 92: 1-18, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31096042

RESUMEN

Nanogels are three-dimensional nanoscale networks formed by physically or chemically cross-linking polymers. Nanogels have been explored as drug delivery systems due to their advantageous properties, such as biocompatibility, high stability, tunable particle size, drug loading capacity, and possible modification of the surface for active targeting by attaching ligands that recognize cognate receptors on the target cells or tissues. Nanogels can be designed to be stimulus responsive, and react to internal or external stimuli such as pH, temperature, light and redox, thus resulting in the controlled release of loaded drugs. This "smart" targeting ability prevents drug accumulation in non-target tissues and minimizes the side effects of the drug. This review aims to provide an introduction to nanogels, their preparation methods, and to discuss the design of various stimulus-responsive nanogels that are able to provide controlled drug release in response to particular stimuli. STATEMENT OF SIGNIFICANCE: Smart and stimulus-responsive drug delivery is a rapidly growing area of biomaterial research. The explosive rise in nanotechnology and nanomedicine, has provided a host of nanoparticles and nanovehicles which may bewilder the uninitiated reader. This review will lay out the evidence that polymeric nanogels have an important role to play in the design of innovative drug delivery vehicles that respond to internal and external stimuli such as temperature, pH, redox, and light.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanogeles/química , Polímeros de Estímulo Receptivo/química , Animales , Liberación de Fármacos , Humanos , Nanogeles/toxicidad , Oxidación-Reducción , Polímeros de Estímulo Receptivo/síntesis química , Temperatura
17.
J Adv Prosthodont ; 10(6): 430-439, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30584472

RESUMEN

The treatment of craniofacial anomalies has been challenging as a result of technological shortcomings that could not provide a consistent protocol to perfectly restore patient-specific anatomy. In the past, wax-up and impression-based maneuvers were implemented to achieve this clinical end. However, with the advent of computer-aided design and computer-aided manufacturing (CAD/CAM) technology, a rapid and cost-effective workflow in prosthetic rehabilitation has taken the place of the outdated procedures. Because the use of implants is so profound in different facets of restorative dentistry, their placement for craniofacial prosthesis retention has also been widely popular and advantageous in a variety of clinical settings. This review aims to effectively describe the well-rounded and interdisciplinary practice of craniofacial prosthesis fabrication and retention by outlining fabrication, osseointegrated implant placement for prosthesis retention, a myriad of clinical examples in the craniofacial complex, and a glimpse of the future of bioengineering principles to restore bioactivity and physiology to the previously defected tissue.

18.
Biomed Microdevices ; 20(3): 66, 2018 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-30088103

RESUMEN

In recent years, there has been growing interest in optically-encoded or tagged functionalized microbeads as a solid support platform to capture proteins or nucleotides which may serve as biomarkers of various diseases. Multiplexing technologies (suspension array or planar array) based on optically encoded microspheres have made possible the observation of relatively minor changes in biomarkers related to specific diseases. The ability to identify these changes at an early stage may allow the diagnosis of serious diseases (e.g. cancer) at a time-point when curative treatment may still be possible. As the overall accuracy of current diagnostic methods for some diseases is often disappointing, multiplexed assays based on optically encoded microbeads could play an important role to detect biomarkers of diseases in a non-invasive and accurate manner. However, detection systems based on functionalized encoded microbeads are still an emerging technology, and more research needs to be done in the future. This review paper is a preliminary attempt to summarize the state-of-the-art concerning diagnostic microbeads; including microsphere composition, synthesis, encoding technology, detection systems, and applications.


Asunto(s)
Análisis por Micromatrices , Microesferas , Línea Celular Tumoral , Simulación por Computador , Citometría de Flujo , Colorantes Fluorescentes , Humanos , Nanopartículas/química , Neoplasias/diagnóstico , Fenómenos Ópticos , Polimerizacion , Proteínas/química , Propiedades de Superficie
19.
Anal Chim Acta ; 1032: 1-17, 2018 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-30143206

RESUMEN

Early diagnosis of diseases (before they become advanced and incurable) is essential to reduce morbidity and mortality rates. With the advent of novel technologies in clinical laboratory diagnosis, microbead-based arrays have come to be recognized as an efficient approach, that demonstrates useful advantages over traditional assay methods for multiple disease-related biomarkers. Multiplexed microbead assays provide a robust, rapid, specific, and cost-effective approach for high-throughput and simultaneous screening of many different targets. Biomolecular binding interactions occur after applying a biological sample (such as blood plasma, saliva, cerebrospinal fluid etc.) containing the target analyte(s) to a set of microbeads with different ligand-specificities that have been coded in planar or suspension arrays. The ligand-receptor binding activity is tracked by optical signals generated by means of flow cytometry analysis in the case of suspension arrays, or by image processing devices in the case of planar arrays. In this review paper, we discuss diagnosis of cancer, neurological and infectious diseases by using optically-encoded microbead-based arrays (both multiplexed and single-analyte assays) as a reliable tool for detection and quantification of various analytes.


Asunto(s)
Detección Precoz del Cáncer , Citometría de Flujo , Neoplasias/diagnóstico , Humanos , Microesferas
20.
Mater Sci Eng C Mater Biol Appl ; 91: 349-360, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30033264

RESUMEN

Lithium and strontium up to 10 mol% have been substituted for calcium in 58S bioactive glasses in order to enhance specific biological properties such as proliferation, alkaline phosphatase (ALP) activity of cells as well as antibacterial activity. In-vitro formation of hydroxyapatite was studied using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), inductively coupled plasma atomic emission spectrometry (ICP-AES) and scanning electron microscopy (SEM). Substitution of either Li or Sr for Ca in the composition had a retarding effect on the bioactivity while Li decreased and Sr increased the rate of ion release in the simulated body fluid solution. The dissolution rate showed to be inversely proportional to oxygen density of the bioactive glasses. The proposed mechanisms for the lowered bioactivity are a lower supersaturation degree for nucleation of apatite in Li substituted bioactive glasses and blocking of the active growth sites of calcium phosphate by Sr2+ in Sr substituted bioactive glasses. The proliferation rate and alkaline phosphate activity of osteoblast cell line MC3T3-E1 treated with Li and Sr bioactive glasses were studied. 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and alkaline phosphate assay showed that all synthesized bioactive glasses with exception of 58S with 10 mol% SrO, exhibited statistically significant increase in both cell proliferation and alkaline phosphatase activity. Finally, 58S bioactive glass with 5 mol% Li2O substitution for CaO was considered as a potential biomaterial in bone repair/regeneration therapies with enhanced biocompatibility, and alkaline phosphate activity, with a negligible loss in the bioactivity compared to the 58S bioglass. At the same time this composition had the highest antibacterial activity against methicillin-resistant Staphylococcus aureus bacteria among all synthesized Li and Sr substituted bioactive glasses.


Asunto(s)
Antibacterianos , Durapatita/metabolismo , Vidrio/química , Litio/química , Osteoblastos/metabolismo , Staphylococcus aureus/crecimiento & desarrollo , Estroncio/química , Animales , Antibacterianos/efectos adversos , Antibacterianos/química , Antibacterianos/farmacología , Calcificación Fisiológica/efectos de los fármacos , Línea Celular , Ratones , Osteoblastos/citología
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