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1.
Drug Dev Ind Pharm ; 50(1): 23-35, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38079333

RESUMEN

OBJECTIVE: This study aimed to develop a mixed polymeric micelle formulation incorporating candesartan cilexetil (CAND) drug to enhance its oral bioavailability for the better treatment of hypertension. METHODS: A Box-Behnken design was utilized to optimize the CAND-incorporated mixed polymeric micelles formulation (CAND-PFLC) consisting of Pluronics (P123 and F68) and lecithin (LC). The optimized CAND-PFLC micelles formulation was characterized for size, shape, zeta potential, polydispersity index (PDI), and entrapment efficiency (%EE). An in vitro release study, ex vivo permeability investigation, and an in vivo pharmacokinetic analysis were carried out to evaluate the performance of the formulation. RESULTS: The optimized CAND-PFLC micelles formulation demonstrated a spherical shape, a particle size of 44 ± 2.03 nm, a zeta potential of -7.07 ± 1.39 mV, a PDI of 0.326 ± 0.06, and an entrapment efficiency of 87 ± 3.12%. The formulation exhibited excellent compatibility, better stability, and a noncrystalline nature. An in vitro release study revealed a faster drug release of 7.98% at gastric pH in 2 hrs and 94.45% at intestinal pH within 24 hrs. The ex vivo investigation demonstrated a significantly enhanced permeability of CAND, with 94.86% in the micelle formulation compared to 9.03% of the pure drug. In vivo pharmacokinetic analysis showed a 4.11-fold increase in oral bioavailability of CAND compared to the marketed formulation. CONCLUSION: The CAND-PFLC mixed micelle formulation demonstrated improved performance compared to pure CAND, indicating its potential as a promising oral drug delivery system for the effective treatment of hypertension.


Asunto(s)
Bencimidazoles , Compuestos de Bifenilo , Hipertensión , Micelas , Tetrazoles , Humanos , Poloxámero/química , Lecitinas , Disponibilidad Biológica , Antihipertensivos , Administración Oral , Liberación de Fármacos , Polímeros/química , Portadores de Fármacos/química , Tamaño de la Partícula
2.
Mol Pharm ; 20(9): 4344-4353, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37523273

RESUMEN

Optimization of the in vivo performance of dosage forms in humans is essential in developing not only conventional formulations but also drug delivery system (DDS) formulations. Although animal experiments are still useful for these formulations, in silico approaches have become increasingly important for DDS formulations with regard to species-specific differences in physiology that can affect the in vivo performance of dosage forms between animals and humans. Furthermore, it is also important to couple in vitro characterizations with in silico models to predict in vivo performance in humans precisely. In this review article, I summarized in vitro-in silico approaches to predicting the in vivo performance of oral DDS formulations (amorphous solid dispersions, lipid-based formulations, nanosized formulations, cyclodextrins-based formulations, sustained release products, enteric coat products, and orally disintegrating tablets) and parenteral DDS formulations (cyclodextrins-based formulations, liposomes, and inhaled formulations).


Asunto(s)
Química Farmacéutica , Ciclodextrinas , Animales , Humanos , Administración Oral , Solubilidad , Sistemas de Liberación de Medicamentos , Simulación por Computador , Comprimidos
3.
J Cell Mol Med ; 26(5): 1501-1514, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35076984

RESUMEN

The importance of the biophysical characterization of mesenchymal stem cells (MSCs) was recently pointed out for supporting the development of MSC-based therapies. Among others, tracking MSCs in vivo and a quantitative characterization of their regenerative impact by nuclear magnetic resonance (NMR) demands a full description of MSCs' MR properties. In the work, Wharton Jelly MSCs are characterized in a low magnetic field (LF) in vitro by using different approaches. They encompass various settings: MSCs cultured in a Petri dish and cell suspensions; experiments- 1D-T 1 , 1D-T 2 , 1D diffusion, 2D T 1 -T 2 and D-T 2 ; devices- with a bore aperture and single-sided one. Complex NMR analysis with the aid of random walk simulations allows the determination of MSCs T 1 and T 2 relaxation times, cells and nuclei sizes, self-diffusion coefficients of the nucleus and cytoplasm. In addition, the influence of a single layer of cells on the effective diffusion coefficient of water is detected with the application of a single-sided NMR device. It also enables the identification of apoptotic and necrotic cell death and changed diffusional properties of cells suspension caused by compressing forces induced by the subsequent cell layers. The study delivers MSCs-specific MR parameters that may help tracking MSCs in vivo.


Asunto(s)
Células Madre Mesenquimatosas , Gelatina de Wharton , Diferenciación Celular , Proliferación Celular/fisiología , Células Cultivadas , Espectroscopía de Resonancia Magnética , Células Madre Mesenquimatosas/metabolismo , Gelatina de Wharton/metabolismo
4.
Nutr Health ; : 2601060221122213, 2022 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-36065597

RESUMEN

Background: Whey proteins and their peptide derivatives have attracted a great attention of researchers in the pharmaceutical and nutritional fields, due to their numerous bio-functionalities. Aim: In the present research study, enzymatic protein hydrolysates (CWPHs) from camel whey proteins (CWPs) were produced and investigated for their antioxidant and antimicrobial potentials. Methods: Herein, Pepsin (gastric), and Trypsin and Chymotrypsin (pancreatic) enzymes were used to produce CWPHs. The obtained hydrolysates were characterize to ascertain the level of protein degradation and studies on their antimicrobial and antioxidant potential were conducted. Results: Among all CWPHs, a complete degradation of all different protein bands was perceived with Chymotrypsin-derived CWPHs, whereas, light bands of serum albumin and α-lactalbumin were observed with Trypsin and Pepsin-derived CWPHs. After enzymatic degradation, both CWPHs antioxidant and antimicrobial activities were improved. Chymotrypsin-derived CWPHs demonstrated higher DPPH and ABTS radical scavenging activities, anent the increase in proteolysis time. Compared to unhydrolyzed CWPs, higher metal chelating activities were displayed by Trypsin-derived CWPHs. No significant increase in the FRAP activities was noticed after CWPs hydrolysis using Trypsin and Chymotrypsin, while Pepsin-derived CWPHs showed higher reducing power. In terms of antimicrobial activity, significantly higher bacterial growth inhibition rates were exhibited by CWPHs compared to the unhydrolyzed CWP. Conclusion: Overall, CWPHs displayed enhanced antioxidative and antimicrobial properties.

5.
Molecules ; 27(13)2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35807252

RESUMEN

Mirtazapine is a tetracyclic anti-depressant with poor water solubility. The aim of this study was to improve the dissolution rate of mirtazapine by delivering the drug as a liquisolid compact. Central composite design (CCD) was employed for the preparation of mirtazapine liquisolid compacts. In this, the impacts of two independent factors, i.e., excipient ratio (carrier:coating) and different drug concentration on the response of liquisolid system were optimized. Liquisolid compacts were prepared using propylene glycol as a solvent, microcrystalline cellulose as a carrier, and silicon dioxide (Aerosil) as the coating material. The crystallinity of the formulated drug and the interactions between the excipients were examined using X-ray powder diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR), respectively. The dissolution study for the liquisolid compact was carried out as per FDA guidelines. The results showed loss of crystallinity of the mirtazapine in the formulation and was completely solubilized in non-volatile solvent and equally dispersed throughout the powder system. Moreover, drug dissolution was found to be higher in liquisolid compacts than the direct compressed conventional tablets (of mirtazapine). The liquisolid technique appears to be a promising approach for improving the dissolution of poorly soluble drugs like mirtazapine.


Asunto(s)
Excipientes , Dióxido de Silicio , Excipientes/química , Mirtazapina , Polvos , Dióxido de Silicio/química , Solubilidad , Solventes/química , Comprimidos/química
6.
AAPS PharmSciTech ; 24(1): 19, 2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36526920

RESUMEN

This study aims to design and characterize berberine-loaded wafers for the treatment of chemotherapy-induced oral mucositis. Wafers were prepared by lyophilization of hydrogels of various ratios of chitosan (CS)/sodium alginate (SA) as well as CS/hydroxypropyl methylcellulose (HPMC). In vitro release, in vitro mucoadhesion, porosity, and swelling studies were conducted to select the optimized formulations. Moreover, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and mechanical properties studies were also performed for further characterization. The efficacy of optimized berberine-loaded wafers in the treatment of oral mucositis was investigated in a 5FU-induced oral mucositis rat model. F2-CS-SA and F6-CS-HPMC wafers exhibited sustained release profile and excellent mucoadhesion strength. Therefore, these wafers were selected as the optimized formulations. SEM confirmed the porous structure of these wafers and is in agreement with the results of porosity and swelling studies. XRD and FTIR studies indicated that berberine was incorporated into the wafer matrix in the amorphous form. In vivo studies demonstrated that topical application of berberine-loaded optimized wafers reduced significantly the severity of 5FU-induced oral mucositis and decreased the expression of inflammatory markers (TNF-α and IL-1ß). The results of in vitro and in vivo studies revealed that berberine-loaded F2-CS-SA and F6-CS-HPMC wafers can be effective in the treatment of chemotherapy-related oral mucositis.


Asunto(s)
Antineoplásicos , Berberina , Quitosano , Estomatitis , Ratas , Animales , Alginatos/química , Quitosano/química , Derivados de la Hipromelosa/química , Estomatitis/inducido químicamente , Estomatitis/tratamiento farmacológico , Espectroscopía Infrarroja por Transformada de Fourier , Fluorouracilo
7.
Int J Mol Sci ; 22(24)2021 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-34948399

RESUMEN

BACKGROUND: Gain of function (GOF) mutations of PCSK9 cause autosomal dominant familial hypercholesterolemia as they reduce the abundance of LDL receptor (LDLR) more efficiently than wild-type PCSK9. In contrast, PCSK9 loss of function (LOF) variants are associated with a hypocholesterolemic phenotype. Dozens of PCSK9 variants have been reported, but most remain of unknown significance since their characterization has not been conducted. OBJECTIVE: Our aim was to make the most comprehensive assessment of PCSK9 variants and to determine the simplest approach for the classification of these variants. METHODS: The expression, maturation, secretion, and activity of nine well-established PCSK9 variants were assessed in transiently transfected HEK293 cells by Western blot and flow cytometry. Their extracellular activities were determined in HepG2 cells incubated with the purified recombinant PCSK9 variants. Their binding affinities toward the LDLR were determined by solid-phase immunoassay. RESULTS: LDLR expression increased when cells were transfected with LOF variants and reduced when cells were transfected with GOF variants compared with wild-type PCSK9. Extracellular activities measurements yielded exactly similar results. GOF and LOF variants had increased, respectively reduced, affinities for the LDLR compared with wild-type PCSK9 with the exception of one GOF variant (R218S) that showed complete resistance to inactivation by furin. All variants were expressed at similar levels and underwent normal maturation and secretion patterns except for two LOF and two GOF mutants. CONCLUSIONS: We propose that transient transfections of HEK293 cells with a plasmid encoding a PCSK9 variant followed by LDLR expression assessment by flow cytometry is sufficient to reliably determine its GOF or LOF status. More refined experiments should only be used to determine the underlying mechanism(s) at hand.


Asunto(s)
Proproteína Convertasa 9/genética , Mutación con Ganancia de Función , Células HEK293 , Células Hep G2 , Humanos , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/metabolismo , Mutagénesis Sitio-Dirigida , Mutación , Proproteína Convertasa 9/metabolismo , Receptores de LDL/metabolismo
8.
AAPS PharmSciTech ; 22(3): 77, 2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33595740

RESUMEN

Currently, periodontitis is treated by oral dosage forms (antibiotics) which shows systemic side effects and failed to reach the therapeutic concentration (above minimum inhibitory concentration, MIC) in the periodontal pocket. The present study aimed to overcome the above issues, by designing tailored doxycycline hyclate laden in situ gel by Poloxamer 407, chitosan, and polyethylene glycol 600. The in situ gel-forming system has attracted attention owing to its ability of sustained drug release above MIC, easy administration (syringeability), and high drug retention (localization) in the periodontal cavity. The Box-Behnken design (BBD) was used to tailor and optimize the concentration of Poloxamer 407 (X1 = 14.3%), chitosan (X2 = 0.58%), and polyethylene glycol 600 (X3 = 1.14%) to achieve sufficient syringeability (149 N), t90% (1105 min), and viscosity at non-physiological condition (512 cps) and physiological condition (5415 cps). The optimized in situ gel was clear and isotonic (RBCs test). The gelation temperature of the optimized in situ was 34 ± 1°C with sufficient mucoadhesive strength (26 ± 2 dyn/cm2), gel strength (29 ± 2 sec), and texture profile for periodontal application. The in vitro drug release studies showed sustain release from optimized in situ gel (24h) in comparison to marketed gel (7h). The antimicrobial activity (cup plate technique) of the in situ gel was equivalent to the marketed doxycycline gel, which suggests that the doxycycline hyclate retained its antimicrobial efficacy when formulated as in situ gelling system. In conclusion, BBD was effectively utilized to optimize in situ gel with minimum level of polymers to achieve the required characteristics of the in situ gel for sustaining drug delivery to treat periodontitis.


Asunto(s)
Antibacterianos/administración & dosificación , Doxiciclina/administración & dosificación , Sistemas de Liberación de Medicamentos , Periodontitis/tratamiento farmacológico , Quitosano/química , Doxiciclina/química , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Geles/administración & dosificación , Humanos , Poloxámero/química , Polímeros/química
9.
Mol Pharm ; 17(11): 4189-4200, 2020 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-32885978

RESUMEN

Nicotine replacement therapy (NRT) formulations for oromucosal administration induce a delayed rise in nicotine blood levels as opposed to the immediate nicotine increase obtained from cigarette smoking, this being a shortcoming of the therapy. Here, we demonstrate that α-lactalbumin/polyethylene oxide (ALA/PEO) electrospun nanofibers constitute an efficient oromucosal delivery system for fast-onset nicotine delivery of high relevance for acute dosing NRT applications. In vitro, nicotine-loaded nanofibers showed fast disintegration in water, with a weight loss up to 40% within minutes, and a faster nicotine release (26.1 ± 4.6% after 1 min of incubation) of the loaded nicotine compared to two relevant marketed NRT formulations with a comparable nicotine dose (i.e., 7.9 ± 5.1 and 2.2 ± 0.3% nicotine was released from a lozenge and a sublingual tablet, respectively). Model-fitting of the release data indicated that the release mechanism of nicotine from the hydrophilic nanofibers was possibly governed by more than one type of release phenomena. Remarkably, ex vivo studies using porcine buccal mucosa demonstrated a more efficient permeation of the nicotine released from the nanofibers [flux of 1.06 ± 0.22 nmol/(cm2·min)] compared to when dosing even a ten-fold concentrated nicotine solution [flux of 0.17 ± 0.14 nmol/(cm2·min)]. Moreover, matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI MS) imaging of ex vivo porcine buccal mucosa exposed to nicotine-loaded nanofibers clearly revealed higher amounts of nicotine throughout the epithelium, as well as in the lamina propria and submucosa of the tissue. Our findings suggest that nicotine-loaded ALA/PEO nanofibers have potential as a mucosal, fast-releasing, and biocompatible delivery system for nicotine, which can overcome the limitations of the currently marketed NRTs.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Lactalbúmina/química , Boca/efectos de los fármacos , Nanofibras/química , Nicotina/administración & dosificación , Nicotina/farmacocinética , Cese del Hábito de Fumar/métodos , Administración Bucal , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Composición de Medicamentos , Liberación de Fármacos , Células Epiteliales/efectos de los fármacos , Epitelio/efectos de los fármacos , Humanos , Mucosa Bucal/efectos de los fármacos , Porcinos , Distribución Tisular , Dispositivos para Dejar de Fumar Tabaco
10.
Int J Mol Sci ; 21(13)2020 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-32645954

RESUMEN

Tissue-resident macrophages are key players in inflammatory processes, and their activation and functionality are crucial in health and disease. Numerous diseases are associated with alterations in homeostasis or dysregulation of the innate immune system, including allergic reactions, autoimmune diseases, and cancer. Macrophages are a prime target for drug discovery due to their major regulatory role in health and disease. Currently, the main sources of macrophages used for therapeutic compound screening are primary cells isolated from blood or tissue or immortalized or neoplastic cell lines (e.g., THP-1). Here, we describe an improved method to employ induced pluripotent stem cells (iPSCs) for the high-yield, large-scale production of cells resembling tissue-resident macrophages. For this, iPSC-derived macrophage-like cells are thoroughly characterized to confirm their cell identity and thus their suitability for drug screening purposes. These iPSC-derived macrophages show strong cellular identity with primary macrophages and recapitulate key functional characteristics, including cytokine release, phagocytosis, and chemotaxis. Furthermore, we demonstrate that genetic modifications can be readily introduced at the macrophage-like progenitor stage in order to interrogate drug target-relevant pathways. In summary, this novel method overcomes previous shortcomings with primary and leukemic cells and facilitates large-scale production of genetically modified iPSC-derived macrophages for drug screening applications.


Asunto(s)
Células Madre Pluripotentes Inducidas/citología , Macrófagos/citología , Técnicas de Cultivo de Célula/métodos , Línea Celular , Quimiotaxis/fisiología , Citocinas/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Macrófagos/metabolismo , Fagocitosis/fisiología
11.
AAPS PharmSciTech ; 21(5): 141, 2020 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-32419084

RESUMEN

Current study is focused to enhance the solubility of poorly soluble drug olanzapine (OLZ) by nanogels drug delivery system, as improved solubility is one of the most important applications of nanosystems. Poor solubility is a major issue, and 40% of marketed and about 75% of new active pharmaceutical ingredients are poorly water soluble which significantly affect the bioavailability and therapeutic effects of these drugs. In this study, nanogels, a promising system for solubility enhancement, were developed by free-radical polymerization technique. Different formulations were synthesized in which poloxamer-407 was cross-linked with 2-acrylamido-2-methylpropane sulfonic acid (AMPS) with the help of cross-linker methylene bisacrylamide (MBA). The chemically cross-linked nanogels were characterized by Fourier transform infrared spectroscopy (FT-IR), thermos gravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), zeta size, swelling, sol-gel analysis, drug loading, solubility, and in vitro drug release studies. In order to determine the biocompatibility and cytotoxicity of nanogels to biological system, toxicity study on rabbits was also carried out. It was confirmed that the developed nanogels was thermally stable, safe, effective, and compatible to biological system, and the solubility of olanzapine (OLZ) was enhanced up to 38 folds as compared with reference product.


Asunto(s)
Antipsicóticos/administración & dosificación , Reactivos de Enlaces Cruzados , Nanogeles , Olanzapina/administración & dosificación , Poloxámero/química , Acrilamidas , Animales , Antipsicóticos/química , Antipsicóticos/toxicidad , Disponibilidad Biológica , Liberación de Fármacos , Excipientes , Radicales Libres , Olanzapina/química , Olanzapina/toxicidad , Tamaño de la Partícula , Conejos , Solubilidad
12.
Exp Cell Res ; 347(1): 1-13, 2016 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-26500109

RESUMEN

The mechanisms by which macrophages control the inflammatory response, wound healing, biomaterial-interactions, and tissue regeneration appear to be related to their activation/differentiation states. Studies of macrophage behavior in vitro can be useful for elucidating their mechanisms of action, but it is not clear to what extent the source of macrophages affects their apparent behavior, potentially affecting interpretation of results. Although comparative studies of macrophage behavior with respect to cell source have been conducted, there has been no direct comparison of the three most commonly used cell sources: murine bone marrow, human monocytes from peripheral blood (PB), and the human leukemic monocytic cell line THP-1, across multiple macrophage phenotypes. In this study, we used multivariate discriminant analysis to compare the in vitro expression of genes commonly chosen to assess macrophage phenotype across all three sources of macrophages, as well as those derived from induced pluripotent stem cells (iPSCs), that were polarized towards four distinct phenotypes using the same differentiation protocols: M(LPS,IFN) (aka M1), M(IL4,IL13) (aka M2a), M(IL10) (aka M2c), and M(-) (aka M0) used as control. Several differences in gene expression trends were found among the sources of macrophages, especially between murine bone marrow-derived and human blood-derived M(LPS,IFN) and M(IL4,IL13) macrophages with respect to commonly used phenotype markers like CCR7 and genes associated with angiogenesis and tissue regeneration like FGF2 and MMP9. We found that the genes with the most similar patterns of expression among all sources were CXCL-10 and CXCL-11 for M(LPS,IFN) and CCL17 and CCL22 for M(IL4,IL13). Human PB-derived macrophages and human iPSC-derived macrophages showed similar gene expression patterns among the groups and genes studied here, suggesting that iPSC-derived monocytes have the potential to be used as a reliable cell source of human macrophages for in vitro studies. These findings could help select appropriate markers when testing macrophage behavior in vitro and highlight those markers that may confuse interpretation of results from experiments employing macrophages from different sources.


Asunto(s)
Polaridad Celular/genética , Perfilación de la Expresión Génica , Macrófagos/citología , Macrófagos/metabolismo , Animales , Materiales Biocompatibles/farmacología , Diferenciación Celular/efectos de los fármacos , Línea Celular , Polaridad Celular/efectos de los fármacos , Análisis Discriminante , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Interferón gamma/farmacología , Análisis de los Mínimos Cuadrados , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Ratones Endogámicos BALB C , Fenotipo
13.
Methods Enzymol ; 699: 343-371, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38942510

RESUMEN

Octocorals are the most prolific source of terpenoids in the marine environment, with more than 4000 different compounds known from the phylum to date. However, the biochemical and genetic origin of their production remained elusive until recent studies showed that octocorals encode genes responsible for the biosynthesis of terpenoids in their own chromosomal DNA rather than from microbial symbionts as originally proposed. The identified coral genes include those encoding a new group of class I terpene cyclases (TCs) clustered among other candidate classes of tailoring enzymes. Phylogenetic analyses established octocoral TCs as a monophyletic clade, distinct from TCs of plants, bacteria, and other organisms. The newly discovered group of TCs appears to be ubiquitous in octocorals and is evolutionarily ancient. Given the recent discovery of octocoral terpenoid biochemistry and only limited genomic data presently available, there is substantial potential for discovering new biosynthetic pathways from octocorals for terpene production. The following chapter outlines practical experimental procedures for octocoral DNA and RNA extraction, genome and transcriptome assembly and mining, TC cloning and gene expression, protein purification, and in vitro analyses.


Asunto(s)
Antozoos , Terpenos , Antozoos/enzimología , Antozoos/genética , Antozoos/metabolismo , Terpenos/metabolismo , Animales , Filogenia , Clonación Molecular/métodos , Transferasas Alquil y Aril/genética , Transferasas Alquil y Aril/metabolismo
14.
ACS Appl Bio Mater ; 6(2): 445-457, 2023 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-36633203

RESUMEN

Recently, injectable hydrogels have attracted much interest in tissue engineering (TE) applications because of their controlled flowability, adaptability, and easy handling properties. This work emphasizes the synthesis and characterizations of bioactive glass (BAG) nanoparticle-reinforced poly(ethylene glycol) (PEG)- and poly(N-vinylcarbazole) (pNVC)-based minimally invasive composite injectable hydrogel suitable for bone regeneration. First, the copolymer was synthesized from a combination of PEG and pNVC through reversible addition-fragmentation chain-transfer (RAFT) polymerization and nanocomposite hydrogel constructs were subsequently prepared by conjugating BAG particles at varying loading concentrations. Gel permeation chromatography (GPC) analysis confirmed the controlled nature of the polymer. Various physicochemical characterization results confirmed the successful synthesis of copolymer and nanocomposite hydrogels that showed good gelling and injectability properties. Our optimal nanocomposite hydrogel formulation showed excellent swelling properties in comparison to the copolymeric hydrogel due to the presence of hydrophilic BAG particles. The bone cell proliferation rate was found to be evidently higher in the nanocomposite hydrogel than in the copolymeric hydrogel. Moreover, the enhanced level of ALP activity and apatite mineralization for the nanocomposite in comparison to that for the copolymeric hydrogel indicates accelerated in vitro osteogenesis. Overall, our study findings indicate BAG particle-conjugated nanocomposite hydrogels can be used as promising grafting materials in orthopedic reconstructive surgeries complementary to conventional bone graft substitutes in cancellous bone defects due to their 3D porous framework, minimal invasiveness, and ability to form any desired shape to match irregular bone defects.


Asunto(s)
Sustitutos de Huesos , Vidrio , Nanogeles , Ingeniería de Tejidos , Sustitutos de Huesos/síntesis química , Hidrogeles/administración & dosificación , Hidrogeles/química , Nanogeles/administración & dosificación , Nanogeles/química , Osteogénesis , Polietilenglicoles/química , Ingeniería de Tejidos/métodos
15.
Front Plant Sci ; 14: 1297090, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38078116

RESUMEN

Introduction: Food crops are increasingly susceptible to the challenging impacts of climate change, encompassing both abiotic and biotic stresses, that cause yield losses. Root-associated microorganisms, including plant growth-promoting bacteria (PGPB), can improve plant growth as well as plant tolerance to environmental stresses. The aims of this work were to characterize bacteria isolated from soil and roots of tomato plants grown in open field. Methods: Biochemical and molecular analyses were used to evaluate the PGP potential of the considered strains on tomato plants in controlled conditions, also assessing their effects under a water deficit condition. The isolated strains were classified by 16S gene sequencing and exhibited typical features of PGPB, such as the release of siderophores, the production of proteases, and phosphorous solubilization. Inoculating tomato plants with eleven selected strains led to the identification of potentially interesting strains that increased shoot height and dry weight. Three strains were then selected for the experiment under water deficit in controlled conditions. The tomato plants were monitored from biometric and physiological point of view, and the effect of inoculation at molecular level was verified with a targeted RT-qPCR based approach on genes that play a role under water deficit condition. Results: Results revealed the PGP potential of different bacterial isolates in tomato plants, both in well-watered and stressed conditions. The used integrated approach allowed to obtain a broader picture of the plant status, from biometric, eco-physiological and molecular point of view. Gene expression analysis showed a different regulation of genes involved in pathways related to abscisic acid, osmoprotectant compounds and heat shock proteins, depending on the treatments. Discussion: Overall, results showed significant changes in tomato plants due to the bacterial inoculation, also under water deficit, that hold promise for future field applications of these bacterial strains, suggesting that a synergistic and complementary interaction between diverse PGPB is an important point to be considered for their exploitation.

16.
Brain Commun ; 5(1): fcad007, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36865673

RESUMEN

Friedreich ataxia is an autosomal recessive multisystem disorder with prominent neurological manifestations and cardiac involvement. The disease is caused by large GAA expansions in the first intron of the FXN gene, encoding the mitochondrial protein frataxin, resulting in downregulation of gene expression and reduced synthesis of frataxin. The selective loss of proprioceptive neurons is a hallmark of Friedreich ataxia, but the cause of the specific vulnerability of these cells is still unknown. We herein perform an in vitro characterization of human induced pluripotent stem cell-derived sensory neuronal cultures highly enriched for primary proprioceptive neurons. We employ neurons differentiated from healthy donors, Friedreich ataxia patients and Friedreich ataxia sibling isogenic control lines. The analysis of the transcriptomic and proteomic profile suggests an impairment of cytoskeleton organization at the growth cone, neurite extension and, at later stages of maturation, synaptic plasticity. Alterations in the spiking profile of tonic neurons are also observed at the electrophysiological analysis of mature neurons. Despite the reversal of the repressive epigenetic state at the FXN locus and the restoration of FXN expression, isogenic control neurons retain many features of Friedreich ataxia neurons. Our study suggests the existence of abnormalities affecting proprioceptors in Friedreich ataxia, particularly their ability to extend towards their targets and transmit proper synaptic signals. It also highlights the need for further investigations to better understand the mechanistic link between FXN silencing and proprioceptive degeneration in Friedreich ataxia.

17.
Eur J Cardiothorac Surg ; 63(5)2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-37137229

RESUMEN

OBJECTIVES: For patients with isolated aortic regurgitation, a double sub- and supravalvular annuloplasty has been shown to reduce recurrent aortic regurgitation after aortic valve repair compared with a single subvalvular annuloplasty. The objective of this study was to compare the geometrical and dynamic properties of single- and double-ring annuloplasties in an in vitro model. METHODS: Eighteen aortic roots from 80 kg pigs were randomized into a control, single-ring and double-ring group. Experiments were conducted in a pulsatile in vitro model. Hydrodynamics, radial force measurements at annular and sinotubular level and 2D echographic imaging were obtained. RESULTS: Both the single- and double-ring annuloplasties downsized the aortic annulus and sinotubular junction (STJ) significantly and increased the coaptation height. The double-ring annuloplasty showed an additional significant increase in coaptation height compared with the single ring [8.5 (0.9)-9.8 (0.8) mm, P < 0.01]. The single-ring annuloplasty reduced radial forces at both levels, whereas the double-ring annuloplasty showed the greatest force reduction of the STJ. CONCLUSIONS: By treating the whole functional aortic annulus, encompassing both the aortic annulus and the STJ, a greater force reduction is observed. A subvalvular annuloplasty alone is efficient in reducing aortic annulus diameter and increasing coaptation height, however, by treating the STJ as well, an additional effect is observed on coaptation height, creating a more efficient stabilization. Reduction of annular force-distensibility ratio with the double-ring annuloplasty compared with the native controls indicates a sustained stabilizing effect.


Asunto(s)
Insuficiencia de la Válvula Aórtica , Procedimientos Quirúrgicos Cardíacos , Anuloplastia de la Válvula Cardíaca , Prótesis Valvulares Cardíacas , Animales , Aorta/cirugía , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/cirugía , Anuloplastia de la Válvula Cardíaca/métodos , Porcinos
18.
Int J Pharm ; 642: 123111, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37302668

RESUMEN

Currently, the spread of antimicrobial resistance dissemination is expanding at an accelerated rate. Therefore, numerous researchers haveinvestigatedalternative treatments in an effort to combat this significant issue. This study evaluated the antibacterial properties of zinc-oxide nanoparticles (ZnO NPs) synthesised by Cycas circinalis against Proteus mirabilis clinical isolates. HPLC was utilised for the identification and quantification of C. circinalis metabolites. The green synthesis of ZnO NPs has been confirmed using UV-VIS spectrophotometry. The Fourier transform infrared spectrum of metal oxide bonds has been compared to the free C. circinalis extract spectrum. The crystalline structure and elemental composition were investigated using X-ray diffraction and Energy-dispersive X-ray techniques. The morphology of nanoparticles was assessed by scanning and transmission electron microscopies, which revealed an average particle size of 26.83 ± 5.87 nm with spherical outlines. The dynamic light scattering technique confirms the optimum stability of ZnO NPs with a zeta potential value equal to 26.4 ± 0.49 mV. Using agar well diffusion and broth microdilution methods, we elucidated the antibacterial activity of ZnO NPs in vitro. MIC values for ZnO NPs ranged from 32 to 128 µg/mL. In 50% of the tested isolates, the membrane integrity was compromised by ZnO nanoparticles. In addition, we assessed the in vivo antibacterial capacity of ZnO NPs by a systemic infection induction using P. mirabilis bacteria in mice. The bacterial count in the kidney tissues was determined, and a significant decrease in CFU/g tissues was observed. The survival rate was evaluated, and the ZnO NPs treated group had higher survival rates. The histopathological studies demonstrated that kidney tissues treated with ZnO NPs had normal structures and architecture. Moreover, the immunohistochemical examinations and ELISA revealed that ZnO NPs substantially decreased the proinflammatory mediators NF-kß, COX-2, TNF-α, IL-6, and IL-1ß in kidney tissues. In conclusion, the results of this study suggest that ZnO NPs are effective against bacterial infections caused by P. mirabilis.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Óxido de Zinc , Animales , Ratones , Óxido de Zinc/farmacología , Óxido de Zinc/química , Proteus mirabilis , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/química , Nanopartículas/química , Óxidos , Extractos Vegetales/química , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de Fourier
19.
Viruses ; 14(11)2022 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-36366481

RESUMEN

Wuxiang virus (WUXV) is a newly discovered Bunyavirales transmitted by sandflies. It is found to infect humans and chickens and can cause neurological symptoms and even death in mice. However, the susceptibility of different hosts and tissue-derived cells to this virus is unclear. In this study, we examined cells derived from murine (BHK-21, N2A), human (HEK-293T, SH-SY5Y), dog (MDCK), pig (PK-15), monkey (Vero), and chicken (DF1), which were inoculated with WUXV at 0.05 MOI, and monitored for monolayer cytopathic effect (CPE). Culture supernatants and cells were collected from 0 to 96 h post-infection, cell viability was determined by trypan blue staining, numbers of infectious virus particles were quantified using plaque tests, and viral nucleic acid contents were determined by RT-qPCR. The presence of WUXV N antigen in infected cells was detected by Western blotting (WB). In response to virus infection, BHK-21, MDCK, and PK-15 cells were characterized by a clear CPE, and we observed reductions in the proportion of viable cells after 96 h. By contrast, no significant CPEs were observed in the other cell lines. We detected increases in viral titers, viral nucleic acid content, and N antigen expression in BHK-21, MDCK, PK-15, HEK-293T, N2A, SH-SY5Y, and DF1 cells post-infection. Vero cells showed no CPE, and the findings for other tests were negative. In conclusion, we tested the susceptibility of different cell lines to WUXV, enhanced our current understanding of WUXV biology at the cellular level, and laid the foundations for further investigation of the underlying virus infection mechanisms.


Asunto(s)
Neuroblastoma , Ácidos Nucleicos , Phlebovirus , Chlorocebus aethiops , Humanos , Animales , Ratones , Porcinos , Perros , Células Vero , Pollos , Línea Celular , Replicación Viral
20.
Materials (Basel) ; 15(4)2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35208062

RESUMEN

Dental floss is an oral hygiene product used to remove food and plaque in places where toothbrushes cannot reach. Even though over the years since its introduction some research in suitable materials has been performed, thread cracking and wear can still compromise efficiency. The aim of this study was to examine the morphological properties of four different commercially available dental floss types before and after use. For that purpose, scanning electron microscopy and optical microscopy were used to assess the flosses before and after use, and tension testing was performed to determine any degradation in the floss performance after utilization. The analyzed floss samples verify the hypothesis that the properties of the floss need to be known in depth, before recommending a specific type to patients for daily use in all clinical indications.

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