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1.
J Am Chem Soc ; 146(25): 17066-17074, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38865160

RESUMEN

The rapid decline in DNA sequencing costs has fueled the demand for nucleic acid collection to unravel genomic information, develop treatments for genetic diseases, and track emerging biological threats. Current approaches to maintaining these nucleic acid collections hinge on continuous electricity for maintaining low-temperature and intricate cold-chain logistics. Inspired by the millennia-long preservation of fossilized biological specimens in calcified minerals or glassy amber, we present Thermoset-REinforced Xeropreservation (T-REX): a method for storing DNA in deconstructable glassy polymer networks. Key to T-REX is the development of polyplexes for nucleic acid encapsulation, streamlining the transfer of DNA from aqueous to organic phases, replete with initiators, monomers, cross-linkers, and thionolactone-based cleavable comonomers required to form the polymer networks. This process successfully encapsulates DNA that spans different length scales, from tens of bases to gigabases, in a matter of hours compared to days with traditional silica-based encapsulation. Further, T-REX permits the extraction of DNA using comparatively benign reagents, unlike the hazardous hydrofluoric acid required for recovery from silica. T-REX provides a path toward low-cost, time-efficient, and long-term nucleic acid preservation for synthetic biology, genomics, and digital information storage, potentially overcoming traditional low-temperature storage challenges.


Asunto(s)
ADN , Polímeros , Polímeros/química , ADN/química , Vidrio/química
2.
J Mater Sci Mater Med ; 35(1): 33, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38900208

RESUMEN

Phosphate bioactive glass has been studied for its advanced biodegradability and active ion release capability. Our previous research found that phosphate glass containing (P2O5)-(Na2O)-(TiO2)-(CaO)-(SrO) or (ZnO) showed good biocompatibility with MG63 and hMSCs. This study further investigated the application of 5 mol% zinc oxide or 17.5 mol% strontium oxide in titanium-doped phosphate glass for bone tissue engineering. Ti-Ca-Na-Phosphate glasses, incorporating 5% zinc oxide or 17.5% strontium oxide, were made with melting quenching technology. The pre-osteoblast cell line MC3T3-E1 was cultured for indirect contact tests with graded diluted phosphate glass extractions and for direct contact tests by seeding cells on glass disks. The cell viability and cytotoxicity were analysed in vitro over 7 days. In vivo studies utilized the tibial defect model with or without glass implants. The micro-CT analysis was performed after surgery and then at 2, 6, and 12 weeks. Extractions from both zinc and strontium phosphate glasses showed no negative impact on MC3T3-E1 cell viability. Notably, non-diluted Zn-Ti-Ca-Na-phosphate glass extracts significantly increased cell viability by 116.8% (P < 0.01). Furthermore, MC3T3-E1 cells cultured with phosphate glass disks exhibited no increase in LDH release compared with the control group. Micro-CT images revealed that, over 12 weeks, both zinc-doped and strontium-doped phosphate glasses demonstrated good bone incorporation and longevity compared to the no-implant control. Titanium-doped phosphate glasses containing 5 mol% zinc oxide, or 17.5 mol% strontium oxide have promising application potential for bone regeneration research.


Asunto(s)
Regeneración Ósea , Supervivencia Celular , Vidrio , Fosfatos , Estroncio , Titanio , Estroncio/química , Estroncio/farmacología , Regeneración Ósea/efectos de los fármacos , Animales , Ratones , Fosfatos/química , Fosfatos/farmacología , Vidrio/química , Titanio/química , Supervivencia Celular/efectos de los fármacos , Ensayo de Materiales , Zinc/química , Línea Celular , Osteoblastos/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Ingeniería de Tejidos/métodos , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Microtomografía por Rayos X
3.
Clin Oral Investig ; 28(7): 386, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38890207

RESUMEN

OBJECTIVE: This study aimed to evaluate the effect of ultrasonic activation of etch-and-rinse and self-etch adhesive systems on the bond strength of resin cement to irradiated root dentin. MATERIALS AND METHODS: Eighty human maxillary anterior teeth were distributed into 8 groups (n = 10), according to the type of adhesive system used (etch-and-rinse and self-etch), the ultrasonic activation of the adhesive systems, and the dentin condition (irradiated or non-irradiated - 70 Gy). Endodontic treatment was performed followed by fiberglass post-space preparation. After fiberglass posts' luting, the roots were transversely sectioned on dentin discs and submitted to the push-out bond strength test (0.5 mm/min). The fractured specimens were analyzed under a stereomicroscope and Scanning Electron Microscope (SEM) for failure mode classification. One of the dentin discs was analyzed under SEM to evaluate the characteristics of the adhesive interface. RESULTS: Irradiated specimens had lower bond strength than non-irradiated specimens (P < 0.0001). Ultrasonic activation of both adhesive systems increased the bond strength of the resin cement to irradiated dentin (P < 0.0001). Radiotherapy significantly affected the failure mode in the middle (P = 0.024) and apical thirds (P = 0.032) (adhesive failure). CONCLUSION: Non-irradiated specimens had a more homogeneous adhesive interface. When ultrasonically activated, both adhesive systems showed a greater number of resinous tags, regardless of the dentin condition. CLINICAL RELEVANCE: Ultrasonic activation of adhesive systems is a feasible strategy to enhance fiberglass posts retention in oncological patients.


Asunto(s)
Recubrimiento Dental Adhesivo , Dentina , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Técnica de Perno Muñón , Cementos de Resina , Humanos , Cementos de Resina/química , Recubrimiento Dental Adhesivo/métodos , Dentina/efectos de la radiación , Técnicas In Vitro , Recubrimientos Dentinarios/química , Análisis del Estrés Dental , Propiedades de Superficie , Raíz del Diente/efectos de la radiación , Ultrasonido , Grabado Ácido Dental , Incisivo , Vidrio/química
4.
Methods Mol Biol ; 2817: 45-56, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38907146

RESUMEN

Single-cell proteomic analyses are of fundamental importance in order to capture biological heterogeneity within complex cell systems' heterogeneous populations. Mass spectrometry (MS)-based proteomics is a promising alternative for quantitative single-cell proteomics. Various techniques are continually evolving to address the challenges of limited sample material, detection sensitivity, and throughput constraints. In this chapter, we describe a nanoliter-scale glass-oil-air-droplet (gOAD) chip engineered for heat tolerance, which combines droplet-based microfluidics and shotgun proteomic analysis techniques to enable multistep sample pretreatment.


Asunto(s)
Vidrio , Proteómica , Análisis de la Célula Individual , Proteómica/métodos , Análisis de la Célula Individual/métodos , Análisis de la Célula Individual/instrumentación , Vidrio/química , Humanos , Aceites/química , Espectrometría de Masas/métodos , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos , Dispositivos Laboratorio en un Chip , Aire , Proteoma/análisis , Nanotecnología/métodos , Nanotecnología/instrumentación , Microfluídica/métodos , Microfluídica/instrumentación
5.
Nature ; 630(8016): 308-309, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38867126
6.
Ann Agric Environ Med ; 31(2): 287-293, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38940114

RESUMEN

INTRODUCTION AND OBJECTIVE: Ultraviolet light in the UV-C band is known as germicidal radiation and was widely used for both sterilization of the equipment and creation of a sterile environment. The aim of the study is to assess the effectiveness of inactivation of microorganisms deposited on surfaces with various textures by UV-C radiation disinfection devices. MATERIAL AND METHODS: Five microorganisms (3 bacteria, virus, and fungus) deposited on metal, plastic, and glass surfaces with smooth and rough textures were irradiated with UV-C light emitted by low-pressure mercury lamp and ultraviolet emitting diodes (LEDs), from a distance of 0.5 m, 1 m, and 1.5 m to check their survivability after 20-minute exposure. RESULTS AND CONCLUSIONS: Both tested UV-C sources were effective in inactivation of microorganisms; however, LED emitter was more efficient in this respect than the mercury lamp. The survival rate of microorganisms depended on the UV-C dose, conditioned by the distance from UV-C source being the highest at 0.5 m and the lowest at 1.5 m. For the tested microorganisms, the highest survival rate after UV-C irradiation was usually visible on glass and plastic surfaces. This observation should be considered in all environments where the type of material (from which the elements of technical equipment are manufactured and may be contaminated by specific activities) is important for maintaining the proper level of hygiene and avoiding the unwanted and uncontrolled spread of microbiological pollution.


Asunto(s)
Bacterias , Desinfección , Hongos , Rayos Ultravioleta , Desinfección/métodos , Desinfección/instrumentación , Hongos/efectos de la radiación , Bacterias/efectos de la radiación , Bacterias/aislamiento & purificación , Virus/efectos de la radiación , Propiedades de Superficie , Viabilidad Microbiana/efectos de la radiación , Plásticos/efectos de la radiación , Plásticos/química , Vidrio/química
7.
Anal Chem ; 96(19): 7470-7478, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38696229

RESUMEN

MicroRNAs (miRNAs) are endogenous and noncoding single-stranded RNA molecules with a length of approximately 18-25 nucleotides, which play an undeniable role in early cancer screening. Therefore, it is very important to develop an ultrasensitive and highly specific method for detecting miRNAs. Here, we present a bottom-up assembly approach for modifying glass microtubes with silica nanowires (SiNWs) and develop a label-free sensing platform for miRNA-21 detection. The three-dimensional (3D) networks formed by SiNWs make them abundant and highly accessible sites for binding with peptide nucleic acid (PNA). As a receptor, PNA has no phosphate groups and exhibits an overall electrically neutral state, resulting in a relatively small repulsion between PNA and RNA, which can improve the hybridization efficiency. The SiNWs-filled glass microtube (SiNWs@GMT) sensor enables ultrasensitive, label-free detection of miRNA-21 with a detection limit as low as 1 aM at a detection range of 1 aM-100 nM. Noteworthy, the sensor can still detect miRNA-21 in the range of 102-108 fM in complex solutions containing 1000-fold homologous interference of miRNAs. The high anti-interference performance of the sensor enables it to specifically recognize target miRNA-21 in the presence of other miRNAs and distinguish 1-, 3-mismatch nucleotide sequences. Significantly, the sensor platform is able to detect miRNA-21 in the lysate of breast cancer cell lines (e.g., MCF-7 cells and MDA-MB-231 cells), indicating that it has good potential in the screening of early breast cancers.


Asunto(s)
Vidrio , MicroARNs , Nanocables , Ácidos Nucleicos de Péptidos , Dióxido de Silicio , MicroARNs/análisis , Ácidos Nucleicos de Péptidos/química , Dióxido de Silicio/química , Humanos , Nanocables/química , Vidrio/química , Técnicas Biosensibles/métodos , Límite de Detección
8.
Mol Pharm ; 21(7): 3591-3602, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38818946

RESUMEN

Coamorphous and cocrystal drug delivery systems provide attractive crystal engineering strategies for improving the solubilities, dissolution rates, and oral bioavailabilities of poorly water-soluble drugs. Polymeric additives have often been used to inhibit the unwanted crystallization of amorphous drugs. However, the transformation of a coamorphous phase to a cocrystal phase in the presence of polymers has not been fully elucidated. Herein, we investigated the effects of low concentrations of the polymeric excipients poly(ethylene oxide) (PEO) and poly(vinylpyrrolidone) (PVP) on the growth of carbamazepine-celecoxib (CBZ-CEL) cocrystals from the corresponding coamorphous phase. PEO accelerated the growth rate of the cocrystals by increasing the molecular mobility of the coamorphous system, while PVP had the opposite effect. The coamorphous CBZ-CEL system exhibited two anomalously fast crystal growth modes: glass-to-crystal (GC) growth in the bulk and accelerated crystal growth at the free surface. These two fast growth modes both disappeared after doping with PEO (1-3% w/w) but were retained in the presence of PVP, indicating a potential correlation between the two fast crystal growth modes. We propose that the different effects of PEO and PVP on the crystal growth modes arose from weaker effects of the polymers on cocrystallization at the surface than in the bulk. This work provides a deep understanding of the mechanisms by which polymers influence the cocrystallization kinetics of a multicomponent amorphous phase and highlights the importance of polymer selection in stabilizing coamorphous systems or preparing cocrystals via solid-based methods.


Asunto(s)
Carbamazepina , Cristalización , Polietilenglicoles , Polímeros , Povidona , Solubilidad , Polímeros/química , Polietilenglicoles/química , Carbamazepina/química , Povidona/química , Excipientes/química , Vidrio/química
9.
Biomed Mater ; 19(4)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38740053

RESUMEN

This study aimed to investigate the effects of magnesium-doped bioactive glass (Mg-BG) on the mineralization, odontogenesis, and anti-inflammatory abilities of human dental pulp stem cells (hDPSCs). Mg-BG powders with different Mg concentrations were successfully synthesized via the sol-gel method and evaluated using x-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. Apatite formation was observed on the surfaces of the materials after soaking in simulated body fluid. hDPSCs were cultured with Mg-BG powder extracts in vitro, and no evident cytotoxicity was observed. Mg-BG induced alkaline phosphatase (ALP) expression and mineralization of hDPSCs and upregulated the expression of odontogenic genes, including those encoding dentin sialophosphoprotein, dentin matrix protein 1, ALP, osteocalcin, and runt-related transcription factor 2. Moreover, Mg-BG substantially suppressed the secretion of inflammatory cytokines (interleukin [IL]-4, IL-6, IL-8, and tumor necrosis factor-alpha). Collectively, the results of this study suggest that Mg-BG has excellent in vitro bioactivity and is a potential material for vital pulp therapy of inflamed pulps.


Asunto(s)
Antiinflamatorios , Pulpa Dental , Vidrio , Magnesio , Células Madre , Humanos , Pulpa Dental/citología , Pulpa Dental/metabolismo , Magnesio/química , Antiinflamatorios/farmacología , Antiinflamatorios/química , Células Madre/citología , Células Madre/metabolismo , Vidrio/química , Odontogénesis/efectos de los fármacos , Citocinas/metabolismo , Células Cultivadas , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Fosfatasa Alcalina/metabolismo , Cerámica/química , Cerámica/farmacología , Ensayo de Materiales , Polvos , Microscopía Electrónica de Rastreo
10.
Mikrochim Acta ; 191(6): 341, 2024 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-38795199

RESUMEN

The construction of gating system in artificial channels is a cutting-edge research direction in understanding biological process and application sensing. Here, by mimicking the gating system, we report a device that easily synthesized single-glass micropipettes functionalized by three-dimensional (3D) DNA network, which triggers the gating mechanism for the detection of biomolecules. Based on this strategy, the gating mechanism shows that single-glass micropipette assembled 3D DNA network is in the "OFF" state, and after collapsing in the presence of ATP, they are in the "ON" state, at which point they exhibit asymmetric response times. In the "ON" process of the gating mechanism, the ascorbic acid phosphate (AAP) can be encapsulated by a 3D DNA network and released in the presence of adenosine triphosphate (ATP), which initiates a catalyzed cascade reaction under the influence of alkaline phosphatase (ALP). Ultimately, the detection of ALP can be responded to form the fluorescence signal generated by terephthalic acid that has captured hydroxyl radicals, which has a detection range of 0-250 mU/mL and a limit of detection of 50 mU/mL. This work provides a brand-new way and application direction for research of gating mechanism.


Asunto(s)
Adenosina Trifosfato , Fosfatasa Alcalina , ADN , Adenosina Trifosfato/análisis , Adenosina Trifosfato/química , Adenosina Trifosfato/metabolismo , Fosfatasa Alcalina/metabolismo , Fosfatasa Alcalina/química , ADN/química , Vidrio/química , Técnicas Biosensibles/métodos , Límite de Detección , Ácido Ascórbico/química , Ácido Ascórbico/análogos & derivados
11.
ACS Biomater Sci Eng ; 10(6): 3923-3934, 2024 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-38766805

RESUMEN

The repair of critical-sized bone defects continues to pose a challenge in clinics. Strontium (Sr), recognized for its function in bone metabolism regulation, has shown potential in bone repair. However, the underlying mechanism through which Sr2+ guided favorable osteogenesis by modulating macrophages remains unclear, limiting their application in the design of bone biomaterials. Herein, Sr-incorporated bioactive glass (SrBG) was synthesized for further investigation. The release of Sr ions enhanced the immunomodulatory properties and osteogenic potential by modulating the polarization of macrophages toward the M2 phenotype. In vivo, a 3D-printed SrBG scaffold was fabricated and showed consistently improved bone regeneration by creating a prohealing immunological microenvironment. RNA sequencing was performed to explore the underlying mechanisms. It was found that Sr ions might enhance the mitochondrial function of macrophage by activating PI3K/AKT/mTOR signaling, thereby favoring osteogenesis. Our findings demonstrate the relationship between the immunomodulatory role of Sr ions and the mitochondrial function of macrophages. By focusing on the mitochondrial function of macrophages, Sr2+-mediated immunomodulation sheds light on the future design of biomaterials for tissue regenerative engineering.


Asunto(s)
Vidrio , Macrófagos , Mitocondrias , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Estroncio , Serina-Treonina Quinasas TOR , Serina-Treonina Quinasas TOR/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/inmunología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Estroncio/farmacología , Estroncio/química , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Células RAW 264.7 , Vidrio/química , Osteogénesis/efectos de los fármacos , Regeneración Ósea/efectos de los fármacos , Andamios del Tejido/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/química , Microambiente Celular/efectos de los fármacos
12.
J Mech Behav Biomed Mater ; 156: 106581, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38776740

RESUMEN

Patient-specific fabrication of scaffold/implant requires an engineering approach to manufacture the ideal scaffold. Herein, we design and 3D print scaffolds comprised of polyether-ether-ketone (PEEK) and sodium-carboxymethyl cellulose (Na-CMC). The fabricated scaffold was dip coated with Zn and Mn doped bioactive glass nanoparticles (Zn-Mn MBGNs). The synthesized ink exhibit suitable shear-thinning behavior for direct ink write (DIW) 3D printing. The scaffolds were crafted with precision, featuring 85% porosity, 0.3 mm layer height, and 1.5 mm/s printing speed at room temperature. Scanning electron microscopy images reveal a well-defined scaffold with an average pore size of 600 ± 30 µm. The energy dispersive X-ray spectroscopy analysis confirmed a well dispersed/uniform coating of Zn-Mn MBGNs on the PEEK/Na-CMC scaffold. Fourier transform infrared spectroscopy approved the presence of PEEK, CMC, and Zn-Mn MBGNs. The tensile test revealed a Young's modulus of 2.05 GPa. Antibacterial assays demonstrate inhibition zone against Staphylococcus aureus and Escherichia Coli strains. Chick Chorioallantoic Membrane assays also present significant angiogenesis potential, owing to the antigenic nature of Zn-Mn MBGNs. WST-8 cell viability assays depicted cell proliferation, with a 103% viability after 7 days of culture. This study suggests that the PEEK/Na-CMC scaffolds coated with Zn-Mn MBGNs are an excellent candidate for osteoporotic fracture treatment. Thus, the fabricated scaffold can offer multifaceted properties for enhanced patient outcomes in the bone tissue regeneration.


Asunto(s)
Benzofenonas , Carboximetilcelulosa de Sodio , Vidrio , Cetonas , Manganeso , Nanopartículas , Polietilenglicoles , Polímeros , Impresión Tridimensional , Staphylococcus aureus , Andamios del Tejido , Zinc , Porosidad , Benzofenonas/química , Vidrio/química , Cetonas/química , Cetonas/farmacología , Andamios del Tejido/química , Staphylococcus aureus/efectos de los fármacos , Carboximetilcelulosa de Sodio/química , Nanopartículas/química , Zinc/química , Zinc/farmacología , Polímeros/química , Manganeso/química , Polietilenglicoles/química , Antibacterianos/química , Antibacterianos/farmacología , Animales , Escherichia coli/efectos de los fármacos , Ensayo de Materiales , Humanos
13.
Int J Biol Macromol ; 270(Pt 1): 132361, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38750857

RESUMEN

Critical-sized bone defects are a major challenge in reconstructive bone surgery and usually fail to be treated due to limited remaining bone quality and extensive healing time. The combination of 3D-printed scaffolds and bioactive materials is a promising approach for bone tissue regeneration. In this study, 3D-printed alkaline-treated polycaprolactone scaffolds (M-PCL) were fabricated and integrated with tragacanth gum- 45S5 bioactive glass (TG-BG) to treat critical-sized calvarial bone defects in female adult Wistar rats. After a healing period of four and eight weeks, the new bone of blank, M-PCL, and M-PCL/TG-BG groups were harvested and assessed. Micro-computed tomography, histological, biochemical, and biomechanical analyses, gene expression, and bone matrix formation were used to assess bone regeneration. The micro-computed tomography results showed that the M-PCL/TG-BG scaffolds not only induced bone tissue formation within the bone defect but also increased BMD and BV/TV compared to blank and M-PCL groups. According to the histological analysis, there was no evidence of bony union in the calvarial defect regions of blank groups, while in M-PCL/TG-BG groups bony integration and repair were observed. The M-PCL/TG-BG scaffolds promoted the Runx2 and collagen type I expression as compared with blank and M-PCL groups. Besides, the bone regeneration in M-PCL/TG-BG groups correlated with TG-BG incorporation. Moreover, the use of M-PCL/TG-BG scaffolds promoted the biomechanical properties in the bone remodeling process. These data demonstrated that the M-PCL/TG-BG scaffolds serve as a highly promising platform for the development of bone grafts, supporting bone regeneration with bone matrix formation, and osteogenic features. Our results exhibited that the 3D-printed M-PCL/TG-BG scaffolds are a promising strategy for successful bone regeneration.


Asunto(s)
Regeneración Ósea , Vidrio , Osteogénesis , Poliésteres , Impresión Tridimensional , Ratas Wistar , Cráneo , Andamios del Tejido , Animales , Poliésteres/química , Andamios del Tejido/química , Ratas , Regeneración Ósea/efectos de los fármacos , Cráneo/efectos de los fármacos , Cráneo/patología , Cráneo/lesiones , Cráneo/diagnóstico por imagen , Osteogénesis/efectos de los fármacos , Femenino , Vidrio/química , Tragacanto/química , Microtomografía por Rayos X , Ingeniería de Tejidos/métodos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología
14.
AAPS PharmSciTech ; 25(5): 103, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714634

RESUMEN

Crystallization of amorphous pharmaceutical solids are widely reported to be affected by the addition of polymer, while the underlying mechanism require deep study. Herein, crystal growth behaviors of glassy griseofulvin (GSF) doped with various 1% w/w polymer were systematically studied. From the molecular structure, GSF cannot form the hydrogen bonding interactions with the selected polymer poly(vinyl acetate), polyvinyl pyrrolidone (PVP), 60:40 vinyl pyrrolidone-vinyl acetate copolymer (PVP/VA 64), and poly(ethylene oxide) (PEO). 1% w/w polymer exhibited weak or no detectable effects on the glass transition temperature (Tg) of GSF. However, crystal growth rates of GSF was altered from 4.27-fold increase to 2.57-fold decrease at 8 ℃ below Tg of GSF. Interestingly, the ability to accelerate and inhibit the growth rates of GSF crystals correlated well with Tg of polymer, indicating the controlling role of segmental mobility of polymer. Moreover, ring-banded growth of GSF was observed in the polymer-doped systems. Normal compact bulk and ring-banded crystals of GSF were both characterized as the thermodynamically stable form I. More importantly, formation of ring-banded crystals of GSF can significantly weaken the inhibitory effects of polymer on the crystallization of glassy GSF.


Asunto(s)
Cristalización , Griseofulvina , Polímeros , Temperatura de Transición , Griseofulvina/química , Cristalización/métodos , Polímeros/química , Estabilidad de Medicamentos , Enlace de Hidrógeno , Polivinilos/química , Polietilenglicoles/química , Povidona/química , Vidrio/química
15.
Sci Rep ; 14(1): 10269, 2024 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-38704450

RESUMEN

Thiamine (vitamin B1) is an essential vitamin serving in its diphosphate form as a cofactor for enzymes in the citric acid cycle and pentose-phosphate pathways. Its concentration reported in the pM and nM range in environmental and clinical analyses prompted our consideration of the components used in pre-analytical processing, including the selection of filters, filter apparatuses, and sample vials. The seemingly innocuous use of glass fiber filters, glass filter flasks, and glass vials, ubiquitous in laboratory analysis of clinical and environmental samples, led to marked thiamine losses. 19.3 nM thiamine was recovered from a 100 nM standard following storage in glass autosampler vials and only 1 nM of thiamine was obtained in the filtrate of a 100 nM thiamine stock passed through a borosilicate glass fiber filter. We further observed a significant shift towards phosphorylated derivatives of thiamine when an equimolar mixture of thiamine, thiamine monophosphate, and thiamine diphosphate was stored in glass (most notably non-silanized glass, where a reduction of 54% of the thiamine peak area was observed) versus polypropylene autosampler vials. The selective losses of thiamine could lead to errors in interpreting the distribution of phosphorylated species in samples. Further, some loss of phosphorylated thiamine derivatives selectively to amber glass vials was observed relative to other glass vials. Our results suggest the use of polymeric filters (including nylon and cellulose acetate) and storage container materials (including polycarbonate and polypropylene) for thiamine handling. Losses to cellulose nitrate and polyethersulfone filters were far less substantial than to glass fiber filters, but were still notable given the low concentrations expected in samples. Thiamine losses were negated when thiamine was stored diluted in trichloroacetic acid or as thiochrome formed in situ, both of which are common practices, but not ubiquitous, in thiamine sample preparation.


Asunto(s)
Vidrio , Tiamina , Tiamina/análisis , Tiamina/química , Vidrio/química , Adsorción , Humanos , Filtración
16.
ACS Appl Mater Interfaces ; 16(19): 24261-24273, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709741

RESUMEN

In this work, bioactive glass (BG) particles obtained by three different methods (melt-quenching, sol-gel, and sol-gel-EISA) were used as modifiers of polyphenol-loaded PCL-based composites. The composites were loaded with polyphenolic compounds (PPh) extracted from sage (Salvia officinalis L.). It was hypothesized that BG particles, due to their different textural properties (porosity, surface area) and surface chemistry (content of silanol groups), would act as an agent to control the release of polyphenols from PCL/BG composite films and other significant properties associated with and affected by the presence of PPh. The polyphenols improved the hydrophilicity, apatite-forming ability, and mechanical properties of the composites and provided antioxidant and anticancer activity. As the BG particles had different polyphenol-binding capacities, they modulated the kinetics of polyphenol release from the composites and the aforementioned properties to a great extent. Importantly, the PPh-loaded materials exhibited multifaceted and selective anticancer activity, including ROS-mediated cell cycle arrest and apoptosis of osteosarcoma (OS) cells (Saos-2) via Cdk2-, GADD45G-, and caspase-3/7-dependent pathways. The materials showed a cytotoxic and antiproliferative effect on cancerous osteoblasts but not on normal human osteoblasts. These results suggest that the composites have great potential as biomaterials for treating bone defects, particularly following surgical removal of OS tumors.


Asunto(s)
Antineoplásicos , Vidrio , Polifenoles , Polifenoles/química , Polifenoles/farmacología , Humanos , Vidrio/química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Poliésteres/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Antioxidantes/química , Antioxidantes/farmacología
18.
Acta Biomater ; 180: 104-114, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38583750

RESUMEN

In the field of orthopedic surgery, there is an increasing need for the development of bone replacement materials for the treatment of bone defects. One of the main focuses of biomaterials engineering are advanced bioceramics like mesoporous bioactive glasses (MBG´s). The present study compared the new bone formation after 12 weeks of implantation of MBG scaffolds with composition 82,5SiO2-10CaO-5P2O5-x 2.5SrO alone (MBGA), enriched with osteostatin, an osteoinductive peptide, (MBGO) or enriched with bone marrow aspirate (MBGB) in a long bone critical defect in radius bone of adult New Zealand rabbits. New bone formation from the MBG scaffold groups was compared to the gold standard defect filled with iliac crest autograft and to the unfilled defect. Radiographic follow-up was performed at 2, 6, and 12 weeks, and microCT and histologic examination were performed at 12 weeks. X-Ray study showed the highest bone formation scores in the group with the defect filled with autograft, followed by the MBGB group, in addition, the microCT study showed that bone within defect scores (BV/TV) were higher in the MBGO group. This difference could be explained by the higher density of newly formed bone in the osteostatin enriched MBG scaffold group. Therefore, MBG scaffold alone and enriched with osteostatin or bone marrow aspirate increase bone formation compared to defect unfilled, being higher in the osteostatin group. The present results showed the potential to treat critical bone defects by combining MBGs with osteogenic peptides such as osteostatin, with good prospects for translation into clinical practice. STATEMENT OF SIGNIFICANCE: Treatment of bone defects without the capacity for self-repair is a global problem in the field of Orthopedic Surgery, as evidenced by the fact that in the U.S alone it affects approximately 100,000 patients per year. The gold standard of treatment in these cases is the autograft, but its use has limitations both in the amount of graft to be obtained and in the morbidity produced in the donor site. In the field of materials engineering, there is a growing interest in the development of a bone substitute equivalent. Mesoporous bioactive glass (MBG´s) scaffolds with three-dimensional architecture have shown great potential for use as a bone substitutes. The osteostatin-enriched Sr-MBG used in this long bone defect in rabbit radius bone in vivo study showed an increase in bone formation close to autograft, which makes us think that it may be an option to consider as bone substitute.


Asunto(s)
Sustitutos de Huesos , Vidrio , Andamios del Tejido , Animales , Conejos , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Andamios del Tejido/química , Vidrio/química , Porosidad , Diáfisis/patología , Diáfisis/diagnóstico por imagen , Diáfisis/efectos de los fármacos , Microtomografía por Rayos X , Osteogénesis/efectos de los fármacos , Cerámica/química , Cerámica/farmacología , Masculino , Proteína Relacionada con la Hormona Paratiroidea/farmacología , Regeneración Ósea/efectos de los fármacos , Fragmentos de Péptidos
19.
ACS Appl Bio Mater ; 7(5): 2966-2981, 2024 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-38652577

RESUMEN

This study presents a facile fabrication of 58S bioactive glass (BG)-polymer composite coatings on a 316L stainless steel (SS) substrate using the electrophoretic deposition technique. The suspension characteristics and deposition kinetics of BG, along with three different polymers, namely ethylcellulose (EC), poly(acrylic acid) (PAA), and polyvinylpyrrolidone (PVP), have been utilized to fabricate the coatings. Among all coatings, 58S BG and EC polymers are selected as the final composite coating (EC6) owing to their homogeneity and good adhesion. EC6 coating exhibits a thickness of ∼18 µm and an average roughness of ∼2.5 µm. Herein, EC6 demonstrates better hydroxyapatite formation compared to PAA and PVP coatings in simulated body fluid-based mineralization studies for a period of 28 days. Corrosion studies of EC6 in phosphate-buffered saline further confirm the higher corrosion resistance properties after 14 days. In vitro cytocompatibility studies using human placental mesenchymal stem cells demonstrate an increase in cellular viability, attachment, and higher proliferation compared to the bare SS substrate. EC6 coatings promote osteogenic differentiation, which is confirmed via the upregulation of the OPN and OCN genes. Moreover, the EC6 sample exhibits improved antibacterial properties against Escherichia coli and Staphylococcus aureus compared to the uncoated ones. The findings of this work emphasize the potential of electrophoretically fabricated BG-EC composite coatings on SS substrates for orthopedic applications.


Asunto(s)
Materiales Biocompatibles Revestidos , Vidrio , Ensayo de Materiales , Polímeros , Acero Inoxidable , Acero Inoxidable/química , Humanos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Vidrio/química , Polímeros/química , Polímeros/farmacología , Corrosión , Tamaño de la Partícula , Propiedades de Superficie , Antibacterianos/farmacología , Antibacterianos/química , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Electroforesis , Supervivencia Celular/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Pruebas de Sensibilidad Microbiana , Proliferación Celular/efectos de los fármacos
20.
J Biomed Mater Res B Appl Biomater ; 112(5): e35406, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38676957

RESUMEN

The field of tissue engineering has witnessed significant advancements in recent years, driven by the pursuit of innovative solutions to address the challenges of bone regeneration. In this study, we developed an electrospun composite scaffold for bone tissue engineering. The composite scaffold is made of a blend of poly(L-lactide-co-ε-caprolactone) (PLCL) and polyethylene glycol (PEG), with the incorporation of calcined and lyophilized silicate-chlorinated bioactive glass (BG) particles. Our investigation involved a comprehensive characterization of the scaffold's physical, chemical, and mechanical properties, alongside an evaluation of its biological efficacy employing alveolar bone-derived mesenchymal stem cells. The incorporation of PEG and BG resulted in elevated swelling ratios, consequently enhancing hydrophilicity. Thermal gravimetric analysis confirmed the efficient incorporation of BG, with the scaffolds demonstrating thermal stability up to 250°C. Mechanical testing revealed enhanced tensile strength and Young's modulus in the presence of BG; however, the elongation at break decreased. Cell viability assays demonstrated improved cytocompatibility, especially in the PLCL/PEG+BG group. Alizarin red staining indicated enhanced osteoinductive potential, and fluorescence analysis confirmed increased cell adhesion in the PLCL/PEG+BG group. Our findings suggest that the PLCL/PEG/BG composite scaffold holds promise as an advanced biomaterial for bone tissue engineering.


Asunto(s)
Células Madre Mesenquimatosas , Poliésteres , Polietilenglicoles , Ingeniería de Tejidos , Andamios del Tejido , Polietilenglicoles/química , Poliésteres/química , Andamios del Tejido/química , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Humanos , Vidrio/química , Ensayo de Materiales
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