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1.
Heliyon ; 10(5): e26456, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38455554

RESUMEN

Nowadays, the demand for processed food items is surging. To fulfil the enhanced demand, a significant impact is laid on the environment, which enhances the carbon footprint being generated. Hence, to overcome this, the avenues of decarbonisation need to be explored. The presented work is aimed at promoting the decarbonisation of the existing practices within the processed food supply chains. It finds strong compliance with the sustainable development goal (SDG-12), focusing on responsible production-consumption mechanisms. For the same, key enactors of decarbonisation are identified and mapped with the practices at various stages of food supply chains, i.e. upstream, downstream, and other allied practices. Based upon these enactors, a relational, hierarchical framework is developed to provide a comprehensive perspective on complex intricacies. This framework is analysed with an innovative approach which comprises the fundamentals of Interval-Valued Intuitionistic Hesitant Fuzzy Set with the Entropy measures. It results in the outranking of the enactors relative to its importance in the decarbonisation of processed food supply chains. Furthermore, the empirical findings are validated by the sensitivity analysis to felicitate robust decision-making. The outcomes of the presented work provide a roadmap and stepped approach to achieve the decarbonisation goals and make production-consumption mechanisms sustainable. It finds implications in the development of the framework, policy formulation, and decisional attributes for the decarbonisation of food supply chains. It focuses on the adoption of strategies that align with global efforts to mitigate climate change and promote a sustainable future.

2.
Radiat Prot Dosimetry ; 200(1): 1-11, 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-37712439

RESUMEN

In this paper, the details of the development and performance characterisation of a compact, low-power gamma spectrometer for environmental gamma radiation monitoring networks are presented. To reduce the power consumption and the size of the spectrometer, a gamma detector comprising a silicon photomultiplier coupled to a Gd3Ga3Al2O12:Ce,B (GGAG:Ce,B) scintillator has been used for gamma spectrometry. Initially, a Monte Carlo simulation study was carried out to verify the suitability of the 5 mm × 5 mm × 5 mm GGAG:Ce,B crystal for spectrometry of gamma sources in the energy range 60-1332 keV. For minimising the power consumption, the signal processing electronics has been custom designed. This electronics was realised using standard off-the-shelf components to reduce the cost. The developed spectrometer is of size 16 cm × 10 cm × 6 cm, weighs 600 g and consumes 600 mW power. The spectrometer is developed such that it could be directly interfaced with GSM/Xbee for wireless communication with the radiation monitoring networks. The lower-level discriminator threshold of the system is 40 keV and the total electronic noise is <20 keV. The experimentally measured sensitivity of the spectrometer for 137Cs (662 keV) is 2.4 cps/µGy/h at 3.5 V overvoltage. The spectrometer offers excellent linearity over the measured energy range of 60-1332 keV and an energy resolution of ~10% for 662 keV gamma-ray at room temperature.


Asunto(s)
Radioisótopos de Cesio , Monitoreo de Radiación , Rayos gamma , Simulación por Computador
3.
J Chem Inf Model ; 63(1): 138-146, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36563083

RESUMEN

Conformational analysis is central to the design of bioactive molecules. It is particularly challenging for macrocycles due to noncovalent transannular interactions, steric interactions, and ring strain that are often coupled. Herein, we simulated the conformations of five macrocycles designed to express a progression of increasing complexity in environment-dependent intramolecular interactions and verified the results against NMR measurements in chloroform and dimethyl sulfoxide. Molecular dynamics using an explicit solvent model, but not the Monte Carlo method with implicit solvation, handled both solvents correctly. Refinement of conformations at the ab initio level was fundamental to reproducing the experimental observations─standard state-of-the-art molecular mechanics force fields were insufficient. Our simulations correctly predicted the intramolecular interactions between side chains and the macrocycle and revealed an unprecedented solvent-induced conformational switch of the macrocyclic ring. Our results provide a platform for the rational, prospective design of molecular chameleons that adapt to the properties of the environment.


Asunto(s)
Dimetilsulfóxido , Simulación de Dinámica Molecular , Solventes/química , Dimetilsulfóxido/química , Conformación Molecular , Cloroformo
4.
Phys Chem Chem Phys ; 24(38): 23790-23801, 2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36156002

RESUMEN

Materials that can depict persistent deep red light under both ultraviolet (UV) and X-ray illumination can be a boon to sustainable economy, particularly for optical imaging, solid state lighting, and anticounterfeiting applications. Herein, we have made a series of compounds starting from ZnGa2O4:Cr3+ to ZnAl2O4:Cr3+ (individual spinel) by substituting the varied concentration of Al3+ in place of Ga3+ in ZnGa2-xAlxO4:Cr3+ (solid solution). By virtue of the structural and defect engineering doping strategy, the photo and radioluminescence are expected to be improved. Both Cr and Al doping was found to be energetically favorable in ZnGa2O4, where the same does not hold true for Ga doping in ZnAl2O4, as indicated by the DFT-calculated defect formation energies. There seems to be ordering around the dopant ion in the solid solutions compared to either ZnGa2O4 or ZnAl2O4 and is also reflected to as lower persistent luminescence (PerL) lifetimes. PerL under UV, in general. was found to be lower with the enhancement in the Al3+ content endowed by the formation of Cr-Cr ion pair, lower probability of antisite formation, and widening band gap. On the other hand, X-ray excited emission enhances in the solid solution due to the decrease in cation inversion and associated defects. Confocal Microscopy showed that larger particles depicted much brighter deep red emission but failed to percolate to the human cells to a detectable limit; hence, future work is needed for the functionalization of the ZnGa2-xAlxO4:Cr3+ spinel. This work could be of great implication in designing need-based materials, where UV and X-ray excitation is required, for deep red emission with persistent characteristics from chromium-doped spinels.

5.
ACS Omega ; 7(6): 5311-5323, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35187346

RESUMEN

Materials with optical multifunctionality such as photoluminescence (PL), radioluminescence, and thermoluminescence (TL) are a boon for a sustainable society. BaHfO3 (barium hafnium oxide [BHO]) under UV irradiation demonstrated visible PL endowed by oxygen vacancies (OVs). Eu3+ doping in BHO (BHOE) introduces f-state impurity levels just below the conduction band for both Eu@Ba and Eu@Hf sites, causing efficient host-to-dopant energy transfer, generating intense 5D0 → 7F1 magnetic dipole transitions (MDT) with internal quantum yield of ∼70%. X-ray photoelectron spectroscopy and electron paramagnetic resonance showed the formation of OVs in both BHO and BHOE samples with more vacancies in the doped sample. The positron lifetime measurements suggested that Eu3+ ions are distributed at both Ba2+ and Hf4+ sites. The association of OVs with Hf4+ and Eu3+ ions due to high charge/radius ratio is considered to be responsible for lowering the symmetry around Eu3+ ions to C 4v in BHOE. Density functional theory studies of defect formation energy justified the same. Time-resolved emission spectroscopy showed distinct spectra for Eu@Ba and Eu@Hf sites corresponding to symmetric and asymmetric environments, respectively. This could be highly relevant in designing color tunable phosphor by forcing dopant ions at one specific site because Eu@Ba displayed orange emission whereas Eu@Hf displayed red emission. We could further harness BHOE for X-ray scintillator application by designing a thin film, which showed efficient conversion of high-energy X-ray into visible light. Under beta irradiation; both BHO and BHOE showed distinct TL glow curves as shallow traps were formed in the former and deep traps in the latter, which could have long-term implications in harnessing this material for persistent luminescence. We believe that BHO/BHOE demonstrated an extraordinary credential as a perovskite for multifunctional applications in the area of defect-induced light emission, UV phosphor, X-ray scintillator, and TL crystals.

6.
J Org Chem ; 86(23): 16582-16592, 2021 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-34767366

RESUMEN

Reaction of thiazoline fused 2-pyridones with alkyl halides in the presence of cesium carbonate opens the thiazoline ring via S-alkylation and generates N-alkenyl functionalized 2-pyridones. In the reaction with propargyl bromide, the thiazoline ring opens and subsequently closes via a [2 + 2] cycloaddition between an in situ generated allene and the α,ß-unsaturated methyl ester. This method enabled the synthesis of a variety of cyclobutane fused thiazolino-2-pyridones, of which a few analogues inhibit amyloid ß1-40 fibril formation. Furthermore, other analogues were able to bind mature α-synuclein and amyloid ß1-40 fibrils. Several thiazoline fused 2-pyridones with biological activity tolerate this transformation, which in addition provides an exocyclic alkene as a potential handle for tuning bioactivity.


Asunto(s)
Ciclobutanos , Alquenos , Péptidos beta-Amiloides , Reacción de Cicloadición , Piridonas
7.
Org Biomol Chem ; 19(44): 9758-9772, 2021 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-34730163

RESUMEN

We herein present the synthesis of diversely functionalized pyrimidine fused thiazolino-2-pyridones via K2S2O8-mediated oxidative coupling of 6-amino-7-(aminomethyl)-thiazolino-2-pyridones with aldehydes. The developed protocol is mild, has wide substrate scope, and does not require transition metal catalyst or base. Some of the synthesized compounds have an ability to inhibit the formation of Amyloid-ß fibrils associated with Alzheimer's disease, while others bind to mature amyloid-ß and α-synuclein fibrils.


Asunto(s)
Aldehídos
8.
Appl Radiat Isot ; 172: 109677, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33711586

RESUMEN

Inorganic scintillator-based gamma spectrometry is typically carried out under laboratory conditions by using systems that require AC mains supply and dedicated computers for their operation. In this study, an in-house grown CsI(Tl) single crystal scintillator is optically coupled to a bialkali photomultiplier tube (PMT). The output of the PMT is fed to a pulse processing chain consisting of a preamplifier followed by an in-house designed and developed field programmable gate array (FPGA) based multichannel analyzer (MCA). Spectral data from this MCA is sent via serial communication to a microcontroller. A global system for mobile communications (GSM) modem transmits this data in the form of short message service (SMS) packets to a central receiving station, where the spectrum is reconstructed. The requirement of on-site data logging computer to store large spectral data has thereby been eliminated, which, in turn, has eliminated the requirement of AC power supply, reduced the overall power consumption and size of the system, and made it possible to develop a standalone solar-powered unit. For further reduction of overall power consumption, the spectrometer is turned-on only when a Geiger Mueller (GM) counter based gross gamma detection circuit, also included in the system, detects an ambient gamma dose rate beyond a pre-set threshold level. A mathematical methodology has also been implemented for restoration of recorded spectra, shifted due to temperature variations in the environment. All these features have been integrated and a standalone, solar-powered and battery operated field-deployable environmental gamma spectrometry system (EGSS) has been developed and tested for open field deployment. Presence of 41Ar in ambient air was successfully detected by the system.

9.
J Med Chem ; 64(2): 1054-1072, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33337880

RESUMEN

Lead generation for difficult-to-drug targets that have large, featureless, and highly lipophilic or highly polar and/or flexible binding sites is highly challenging. Here, we describe how cores of macrocyclic natural products can serve as a high-quality in silico screening library that provides leads for difficult-to-drug targets. Two iterative rounds of docking of a carefully selected set of natural-product-derived cores led to the discovery of an uncharged macrocyclic inhibitor of the Keap1-Nrf2 protein-protein interaction, a particularly challenging target due to its highly polar binding site. The inhibitor displays cellular efficacy and is well-positioned for further optimization based on the structure of its complex with Keap1 and synthetic access. We believe that our work will spur interest in using macrocyclic cores for in silico-based lead generation and also inspire the design of future macrocycle screening collections.


Asunto(s)
Productos Biológicos/química , Compuestos Policíclicos/síntesis química , Compuestos Policíclicos/farmacología , Simulación por Computador , Minería de Datos , Bases de Datos Factuales , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/antagonistas & inhibidores , Proteína 1 Asociada A ECH Tipo Kelch/química , Microsomas Hepáticos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Factor 2 Relacionado con NF-E2 , Compuestos Policíclicos/química , Solubilidad , Relación Estructura-Actividad
10.
J Org Chem ; 85(21): 14174-14189, 2020 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-33099999

RESUMEN

A BF3·OEt2 catalyzed intramolecular Povarov reaction was used to synthesize 15 chromenopyridine fused thiazolino-2-pyridone peptidomimetics. The reaction works with several O-alkylated salicylaldehydes and amino functionalized thiazolino-2-pyridones, to generate polyheterocycles with diverse substitution. The synthesized compounds were screened for their ability to bind α-synuclein and amyloid ß fibrils in vitro. Analogues substituted with a nitro group bind to mature amyloid fibrils, and the activity moreover depends on the positioning of this functional group.


Asunto(s)
Amiloide , alfa-Sinucleína , Péptidos beta-Amiloides , Piridonas
11.
Diabetes Metab Syndr ; 14(4): 661-664, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32438329

RESUMEN

BACKGROUND AND AIMS: During COVID-19 pandemic, researchers are using innovative technologies for fast-tracking the development to end this menace. Virtual Reality (VR) also offers an imperative role for fighting this pandemic, through audiovisual-based virtual communication. METHODS: A brief study on Virtual Reality and its applications for the COVID-19 pandemic is carried out by employing keywords as Virtual reality or VR and COVID-19 from the databases of SCOPUS, Google Scholar, PubMed, Web of science Academia and ResearchGate. RESULTS: VR is beneficial for remote sites for exploring telemedicine, planning, treatment, and controlling of the infections by providing proper awareness to the people regarding this disease. CONCLUSIONS: VR technology develops a platform to reduce the face to face interaction of doctors with the infected COVID-19 patients. Through live video streaming, it helps to improve surveillance systems on the ongoing situation.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/terapia , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/terapia , Telemedicina/tendencias , Realidad Virtual , COVID-19 , Infecciones por Coronavirus/prevención & control , Sistemas de Apoyo a Decisiones Clínicas , Encuestas de Atención de la Salud , Humanos , Pandemias/prevención & control , Educación del Paciente como Asunto , Neumonía Viral/prevención & control , Pautas de la Práctica en Medicina
12.
Chemistry ; 26(1): 49-88, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31483909

RESUMEN

Drugs in the chemical space beyond the rule of 5 (bRo5) can modulate targets with difficult binding sites while retaining cell permeability and oral absorption. Reviewing the syntheses of bRo5 drugs approved since 1990 highlights synthetic chemistry's contribution to drug discovery in this space. Initially, bRo5 drugs were mainly natural products and semi-synthetic derivatives. Later, peptidomimetics and de novo designed compounds, that include up to seven chiral centres and macrocyclic rings became dominant. These drugs are prepared by total synthesis, sometimes by routes of more than 25 steps with stereocentres originating from the chiral pool, or being installed by chiral induction or enzymatic resolution. Interestingly, ring-closing metathesis proved to be the method of choice for macrocyclisation in hepatitis C virus protease inhibitors. We conclude that structural simplification, planning of synthetic routes regarding incorporation of stereocentres and macrocyclisation, as well as incorporation of structural knowledge and consideration of chameleonic properties in design, should facilitate drug discovery in bRo5 space.


Asunto(s)
Descubrimiento de Drogas , Preparaciones Farmacéuticas/síntesis química , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Sitios de Unión , Hepacivirus/enzimología , Compuestos Macrocíclicos/síntesis química , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/metabolismo , Peptidomiméticos , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/metabolismo , Inhibidores de Proteasas/síntesis química , Inhibidores de Proteasas/química , Inhibidores de Proteasas/metabolismo , Ribosomas/química , Ribosomas/metabolismo , Proteínas Virales/química , Proteínas Virales/metabolismo
13.
RSC Adv ; 9(34): 19819-19827, 2019 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-35519397

RESUMEN

A simple molecular framework obtained by cross-linking a hydrophobic chain with S,S- and R,R-tetritol by the copper-catalysed azide-alkyne cycloaddition reaction is found to serve as an excellent bioisostere for self-assembly. The hexadecyl-linked triazolyl tetritol composite spontaneously self-assembles in n-hepane and methanol to form hierarchical organogels. Microscopic analyses and X-ray diffraction studies demonstrate eventual formation of nanotubes through lamellar assembly of the amphiphiles. A rheological investigation shows solvent-dictated mechanical properties that obey power law behavior similar to other low molecular weight gelators (LMOGs). The gel network was then utilized for the entrapment of drugs e.g. ibuprofen and 5-fluorouracil, with tunable mechanical behaviour under applied stress. The differential release profiles of the drugs over a period of a few hours as a result of the relative spatio-temporal location in the supramolecular network can be utilized for topical formulations.

14.
Org Lett ; 20(18): 5737-5742, 2018 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-30207734

RESUMEN

A series of macrocycles inspired by natural products were synthesized to investigate how side-chains may shield amide bonds and influence cell permeability. NMR spectroscopy and X-ray crystallography revealed that the phenyl group of phenylalanine, but not the side-chains of homologous or aliphatic amino acids, shields the adjacent amide bond through an intramolecular NH-π interaction. This resulted in increased cell permeability, suggesting that NH-π interactions may be used in the design of molecular chameleons.


Asunto(s)
Amidas/química , Compuestos Macrocíclicos/farmacología , Permeabilidad/efectos de los fármacos , Animales , Cristalografía por Rayos X , Lagartos , Compuestos Macrocíclicos/síntesis química , Compuestos Macrocíclicos/química , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Estructura Molecular
15.
Artículo en Inglés | MEDLINE | ID: mdl-29977103

RESUMEN

Surgical simulators are powerful tools that assist in providing advanced training for complex craniofacial surgical procedures and objective skills assessment such as the ones needed to perform Bilateral Sagittal Split Osteotomy (BSSO). One of the crucial steps in simulating BSSO is accurately cutting the mandible in a specific area of the jaw, where surgeons rely on high fidelity visual and haptic cues. In this paper, we present methods to simulate drilling and cutting of the bone using the burr and the motorized oscillating saw respectively. Our method allows low computational cost bone drilling or cutting while providing high fidelity haptic feedback that is suitable for real-time virtual surgery simulation.

16.
J Med Chem ; 61(11): 4774-4790, 2018 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-29727183

RESUMEN

Strategies that target multiple components are usually required for treatment of diseases originating from complex biological systems. The multicomponent system consisting of the DR4 major histocompatibility complex type II molecule, the glycopeptide CII259-273 from type II collagen, and a T-cell receptor is associated with development of rheumatoid arthritis (RA). We introduced non-native amino acids and amide bond isosteres into CII259-273 and investigated the effect on binding to DR4 and the subsequent T-cell response. Molecular dynamics simulations revealed that complexes between DR4 and derivatives of CII259-273 were highly dynamic. Signaling in the overall multicomponent system was found to depend on formation of an appropriate number of dynamic intramolecular hydrogen bonds between DR4 and CII259-273, together with the positioning of the galactose moiety of CII259-273 in the DR4 binding groove. Interestingly, the system tolerated modifications at several positions in CII259-273, indicating opportunities to use analogues to increase our understanding of how rheumatoid arthritis develops and for evaluation as vaccines to treat RA.


Asunto(s)
Artritis Reumatoide/metabolismo , Artritis Reumatoide/patología , Transducción de Señal , Línea Celular , Antígeno HLA-DR4/química , Antígeno HLA-DR4/metabolismo , Humanos , Simulación de Dinámica Molecular , Estructura Secundaria de Proteína , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/química , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Transducción de Señal/efectos de los fármacos , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo
17.
ACS Appl Mater Interfaces ; 9(42): 37310-37320, 2017 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-28990750

RESUMEN

Organic-inorganic nanocomposite self-standing films of Gd3Ga3Al2O12 (GGAG) uniformly dispersed in poly(methyl methacrylate) (PMMA) and polystyrene polymer are prepared for radiography application. GGAG:Ce nanoscintillator has been chosen because of its high light output and fast decay time. The nanopowder of GGAG is synthesized by coprecipitation method and dispersed in the polymer matrix by a simple blending technique. The nanocomposite films of thickness in the range of 150-450 µm with a very high inorganic content is achieved by this technique. These films are characterized by their uniformity, optical absorption, photoluminescence, and radioluminescence. These films are further tested for their application in radiography by recording X-ray images using a commercially available charge-coupled device camera. A resolution of 10 lp/mm is obtained using GGAG:PMMA composite film with 50% loading, confirming their application in imaging devices.

18.
J Emerg Med ; 53(5): 746-748, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28874303

RESUMEN

BACKGROUND: Fiberoptic bronchoscope-guided tracheal intubation is the gold standard for managing patients with supraglottic growths. In infants with a large and overhanging epiglottis, the success of fiberoptic-guided intubation relies heavily on the available space between the inferior surface of the epiglottis and the posterior pharyngeal wall or, more specifically, the superior surface of the supraglottic growth. CASE REPORT: We describe the inability to negotiate the tip of the fiberscope between the epiglottis and the supraglottic growth and the successful use of direct laryngoscopy to improve the available space along with the usefulness of "bubbling of air" to locate the glottic opening in an infant. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: We emphasize the role of the emergency physician in managing such patients. Most of the time, the setting is not ideal in such emergency situations and the most qualified clinician to treat them is the emergency physician. The knowledge and skills of the emergency physician, along with awareness of the possible techniques for airway management, can be lifesaving.


Asunto(s)
Manejo de la Vía Aérea/métodos , Glotis/anomalías , Intubación Intratraqueal/normas , Manejo de la Vía Aérea/normas , Competencia Clínica/normas , Servicio de Urgencia en Hospital/organización & administración , Tecnología de Fibra Óptica/instrumentación , Tecnología de Fibra Óptica/métodos , Glotis/cirugía , Humanos , Lactante , Intubación Intratraqueal/métodos , Laringoscopía/instrumentación , Laringoscopía/métodos , Masculino
19.
Med Phys ; 44(8): 4194-4203, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28547868

RESUMEN

PURPOSE: Elastography has emerged as a new tool for detecting and diagnosing many types of diseases including breast cancer. To date, most clinical applications of elastography have utilized two-dimensional strain images. The goal of this paper is to present a new quasi-static elastography technique that yields shear modulus images in three dimensions. METHODS: An automated breast volume scanner was used to acquire ultrasound images of the breast as it was gently compressed. Cross-correlation between successive images was used to determine the displacement within the tissue. The resulting displacement field was filtered of all but compressive motion through principal component analysis. This displacement field was used to infer spatial distribution of shear modulus by solving a 3D elastic inverse problem. RESULTS: Three dimensional shear modulus images of benign breast lesions for two subjects were generated using the techniques described above. It was found that the lesions were visualized more clearly in images generated using the displacement data de-noised through the use of principal components. CONCLUSIONS: We have presented experimental and algorithmic techniques that lead to three-dimensional imaging of shear modulus using quasi-static elastography. This work demonstrates feasibility of this approach, and lays the foundation for images of other, more informative, mechanical parameters.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Fantasmas de Imagen , Análisis de Componente Principal , Mama , Módulo de Elasticidad , Diagnóstico por Imagen de Elasticidad , Femenino , Humanos , Estrés Mecánico
20.
Eur J Pharm Sci ; 82: 86-96, 2016 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-26588875

RESUMEN

Curcumin is a natural dietary compound with demonstrated potential in preventing/treating several chronic diseases in animal models. However, this success is yet to be translated to humans mainly because of its poor oral bioavailability caused by extremely low water solubility. This manuscript demonstrates that water insoluble curcumin (~1µg/ml) forms highly aqueous soluble complexes (>2mg/ml) with a safe pH sensitive polymer, poly(butyl-methacrylate-co-(2-dimethylaminoethyl) methacrylate-co-methyl-methacrylate) when precipitated together in water. The complexation process was optimized to enhance curcumin loading by varying several formulation factors. Acetone as a solvent and polyvinyl alcohol as a stabilizer with 1:2 ratio of drug to polymer yielded complexes with relatively high loading (~280µg/ml) and enhanced solubility (>2mg/ml). The complexes were amorphous in solid and were soluble only in buffers with pHs less than 5.0. Hydrogen bond formation and hydrophobic interactions between curcumin and the polymer were recorded by infrared spectroscopy and nuclear magnetic resonance spectroscopy, respectively. Molecular complexes of curcumin were more stable at various pHs compared to unformulated curcumin. In mice, these complexes increased peak plasma concentration of curcumin by 6 times and oral bioavailability by ~20 times. This is a simple, economic and safer strategy of enhancing the oral bioavailability of curcumin.


Asunto(s)
Curcumina/química , Curcumina/farmacocinética , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacocinética , Animales , Disponibilidad Biológica , Estabilidad de Medicamentos , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Ratones Endogámicos BALB C , Solubilidad
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