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1.
AAPS PharmSciTech ; 25(4): 74, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575778

RESUMEN

Advancements in recombinant DNA technology have made proteins and peptides available for diagnostic and therapeutic applications, but their effectiveness when taken orally leads to poor patient compliance, requiring clinical administration. Among the alternative routes, transmucosal delivery has the advantage of being noninvasive and bypassing hepato-gastrointestinal clearance. Various mucosal routes-buccal, nasal, pulmonary, rectal, and vaginal-have been explored for delivering these macromolecules. Nanofibers, due to their unique properties like high surface-area-to-volume ratio, mechanical strength, and improved encapsulation efficiency, serve as promising carriers for proteins and peptides. These nanofibers can be tailored for quick dissolution, controlled release, enhanced encapsulation, targeted delivery, and improved bioavailability, offering superior pharmaceutical and pharmacokinetic performance compared to conventional methods. This leads to reduced dosages, fewer side effects, and enhanced patient compliance. Hence, nanofibers hold tremendous potential for protein/peptide delivery, especially through mucosal routes. This review focuses on the therapeutic application of proteins and peptides, challenges faced in their conventional delivery, techniques for fabricating different types of nanofibers and, various nanofiber-based dosage forms, and factors influencing nanofiber generation. Insights pertaining to the precise selection of materials used for fabricating nanofibers and regulatory aspects have been covered. Case studies wherein the use of specific protein/peptide-loaded nanofibers and delivered via oral/vaginal/nasal mucosa for diagnostic/therapeutic use and related preclinical and clinical studies conducted have been included in this review.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanofibras , Femenino , Humanos , Sistemas de Liberación de Medicamentos/métodos , Nanofibras/química , Proteínas , Péptidos , Preparaciones Farmacéuticas
2.
AAPS PharmSciTech ; 25(7): 222, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39322792

RESUMEN

Overactive bladder (OAB) is a usual medical syndrome that affects the bladder, and Mirabegron (MBG) is preferred medicine for its control. Currently, available marketed formulations (MYRBETRIQ® granules and MYRBETRIQ® ER tablets) suffer from low bioavailability (29-35%) hampering their therapeutic effectiveness and compromising patient compliance. By creating MBG nanostructured lipid carriers (MBG-NLCs) for improved systemic availability and drug release, specifically in oral administration of OAB treatment, this study aimed to address these issues. MBG-NLCs were fabricated using a hot-melt ultrasonication technique. MBG-GMS; MBG-oleic acid interaction was assessed by in silico molecular docking. QbD relied on the concentration of Span 80 (X1) and homogenizer speed (X2) as critical material attribute (CMA) and critical process parameter (CPP) respectively, while critical quality attributes (CQA) such as particle size (Y1) and cumulative drug release at 24 h (Y2) were estimated as dependent variables. 32 factorial design was utilized to investigate the interconnection in variables that are dependent and independents. Optimized MBG-NLCs with a particle size of 194.4 ± 2.25 nm were suitable for lymphatic uptake. A PDI score of 0.275 ± 0.02 and zeta potential of -36.2 ± 0.721 mV indicated a uniform monodisperse system with stable dispersion properties. MBG-NLCs exhibited entrapment efficiency of 77.3 ± 1.17% and a sustained release in SIF of 94.75 ± 1.60% for 24 h. MBG-NLCs exhibited the Higuchi model with diffusion as a release mechanism. A pharmacokinetic study in Wistar rats exhibited a 1.67-fold higher bioavailability as compared to MBG suspension. Hence, MBG-NLCs hold promise for treating OAB by improving MBG's oral bio absorption.


Asunto(s)
Acetanilidas , Disponibilidad Biológica , Portadores de Fármacos , Liberación de Fármacos , Lípidos , Nanoestructuras , Tamaño de la Partícula , Tiazoles , Tiazoles/farmacocinética , Tiazoles/química , Tiazoles/administración & dosificación , Portadores de Fármacos/química , Animales , Ratas , Acetanilidas/farmacocinética , Acetanilidas/administración & dosificación , Acetanilidas/química , Nanoestructuras/química , Lípidos/química , Administración Oral , Química Farmacéutica/métodos , Simulación del Acoplamiento Molecular/métodos , Masculino , Ratas Wistar , Vejiga Urinaria Hiperactiva/tratamiento farmacológico
3.
AAPS PharmSciTech ; 25(7): 205, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39237656

RESUMEN

Oral Topiramate therapy is associated with systemic adverse effects including paresthesia,abdominal pain, and fluctuations in plasma levels. The purpose of this research was to develop an intranasal in situ gel based system comprising Topiramate polymeric nanoparticles and evaluate its potential both in vitro and in vivo. Poly (lactic-co-glycolic acid) (PLGA)nanoparticles prepared by nanoprecipitation method were added into the in situ gelling system of Poloxamer 407 and HPMC K4M. Selected formulation (TG5) was evaluated for physicochemical properties, nasal permeation and in vivo pharmacokinetics in rats. PLGAnanoparticles (O1) exhibited low particle size (~ 144.4 nm), good polydispersity index (0.202), negative zeta potential (-12.7 mV), and adequate entrapment efficiency (64.7%). Developed in situ gel showed ideal pH (6.5), good gelling time (35 s), gelling temperature(37℃), suitable viscosity (1335 cP)and drug content of 96.2%. In vitro drug release conformedto Higuchi release kinetics, exhibiting a biphasic pattern of initial burst release and sustained release for 24 h. Oral administration of the drug to Sprague-Dawley rats (G3) showed higher plasma Cmax(504 ng/ml, p < 0.0001) when compared to nasal delivery of in situ gel (G4) or solution (G5). Additionally, AUC0-α of G3 (8786.82 ng/ml*h) was considerably higher than othergroups. Brain uptake data indicates a higher drug level with G4 (112.47 ng /ml) at 12 h when compared to G3. Histopathological examination of groups; G1 (intranasal saline), G2(intranasal placebo), G3, G4, and G5 did not show any lesions of pathological significance. Overall, the experimental results observed were promising and substantiated the potential of developed in situ gel for intranasal delivery.


Asunto(s)
Administración Intranasal , Encéfalo , Geles , Nanopartículas , Mucosa Nasal , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas Sprague-Dawley , Topiramato , Animales , Topiramato/administración & dosificación , Topiramato/farmacocinética , Nanopartículas/química , Ratas , Administración Intranasal/métodos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Mucosa Nasal/metabolismo , Mucosa Nasal/efectos de los fármacos , Masculino , Tamaño de la Partícula , Fructosa/administración & dosificación , Fructosa/farmacocinética , Fructosa/química , Portadores de Fármacos/química , Liberación de Fármacos , Sistemas de Liberación de Medicamentos/métodos , Ácido Láctico/química , Ácido Láctico/administración & dosificación , Ácido Poliglicólico/química , Administración Oral
4.
J Gen Intern Med ; 38(8): 1902-1910, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36952085

RESUMEN

BACKGROUND: The COVID-19 pandemic required clinicians to care for a disease with evolving characteristics while also adhering to care changes (e.g., physical distancing practices) that might lead to diagnostic errors (DEs). OBJECTIVE: To determine the frequency of DEs and their causes among patients hospitalized under investigation (PUI) for COVID-19. DESIGN: Retrospective cohort. SETTING: Eight medical centers affiliated with the Hospital Medicine ReEngineering Network (HOMERuN). TARGET POPULATION: Adults hospitalized under investigation (PUI) for COVID-19 infection between February and July 2020. MEASUREMENTS: We randomly selected up to 8 cases per site per month for review, with each case reviewed by two clinicians to determine whether a DE (defined as a missed or delayed diagnosis) occurred, and whether any diagnostic process faults took place. We used bivariable statistics to compare patients with and without DE and multivariable models to determine which process faults or patient factors were associated with DEs. RESULTS: Two hundred and fifty-seven patient charts underwent review, of which 36 (14%) had a diagnostic error. Patients with and without DE were statistically similar in terms of socioeconomic factors, comorbidities, risk factors for COVID-19, and COVID-19 test turnaround time and eventual positivity. Most common diagnostic process faults contributing to DE were problems with clinical assessment, testing choices, history taking, and physical examination (all p < 0.01). Diagnostic process faults associated with policies and procedures related to COVID-19 were not associated with DE risk. Fourteen patients (35.9% of patients with errors and 5.4% overall) suffered harm or death due to diagnostic error. LIMITATIONS: Results are limited by available documentation and do not capture communication between providers and patients. CONCLUSION: Among PUI patients, DEs were common and not associated with pandemic-related care changes, suggesting the importance of more general diagnostic process gaps in error propagation.


Asunto(s)
COVID-19 , Adulto , Humanos , COVID-19/epidemiología , Estudios Retrospectivos , Pandemias , Prevalencia , Errores Diagnósticos , Prueba de COVID-19
5.
J Chem Inf Model ; 63(3): 846-855, 2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36719788

RESUMEN

Inappropriate use of prescription drugs is potentially more harmful in fetuses/neonates than in adults. Cytochrome P450 (CYP) 3A subfamily undergoes developmental changes in expression, such as a transition from CYP3A7 to CYP3A4 shortly after birth, which provides a potential way to distinguish medication effects on fetuses/neonates and adults. The purpose of this study was to build first-in-class predictive models for both inhibitors and substrates of CYP3A7/CYP3A4 using chemical structure analysis. Three metrics were used to evaluate model performance: area under the receiver operating characteristic curve (AUC-ROC), balanced accuracy (BA), and Matthews correlation coefficient (MCC). The performance varied for each CYP3A7/CYP3A4 inhibitor/substrate model depending on the data set type, model type, rebalancing method, and specific feature set. For the active inhibitor/substrate data set, the optimal models achieved AUC-ROC values ranging from 0.77 ± 0.01 to 0.84 ± 0.01. For the selective inhibitor/substrate data set, the optimal models achieved AUC-ROC values ranging from 0.72 ± 0.02 to 0.79 ± 0.04. The predictive power of the optimal models was validated by compounds with known potencies as CYP3A7/CYP3A4 inhibitors or substrates. In addition, we identified structural features significant for CYP3A7/CYP3A4 selective or common inhibitors and substrates. In summary, the top performing models can be further applied as a tool to rapidly evaluate the safety and efficacy of new drugs separately for fetuses/neonates and adults. The significant structural features could guide the design of new therapeutic drugs as well as aid in the optimization of existing medicine for fetuses/neonates.


Asunto(s)
Citocromo P-450 CYP3A , Recién Nacido , Adulto , Humanos , Citocromo P-450 CYP3A/metabolismo , Área Bajo la Curva
6.
AAPS PharmSciTech ; 24(7): 176, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37639081

RESUMEN

Rivaroxaban (RXN) finds use in the management of pulmonary embolism and deep vein thrombosis. Its poor solubility (5-7 µg/mL) and P-gp-mediated efflux from intestinal lining limits the oral application of RXN. This work assessed the impact of liquisolid compact technique in augmenting the solubility and bioavailability of RXN. PEG 400, Avicel PH 200, and Aerosil 200 were used as non-volatile liquid, carrier, and coating material, respectively, to formulate RXN liquid-solid compacts (RXN LSCs). A 32-factor factorial design was used in the optimisation to assess the impacts of factors (load factor and carrier:coating ratio) on the responses (angle of repose and Q30 min). Pre-compression parameters of RXN LSCs suggested adequate flow and compressibility. Optimisation data suggested significant influence of factors on both the responses. Optimised RXN LSC-based tablets showed a significantly higher in vitro dissolution rate than RXN API and Xarelto® tablets due to improved solubility, reduced crystallinity, greater surface area, and enhanced wetting of RXN particles. XRD, DSC, and SEM data supported RXN's amorphization. The cytotoxicity (MTT assay) and permeation studies indicated the nontoxicity of prepared RXN LSC tablets and the role of PEG 400 in inhibiting P-gp. Pharmacokinetic study of RXN LSC-based tablets in Albino Wistar rats exhibited 2.51- and 1.66-times higher AUC in comparison to RXN API and Xarelto® tablets respectively, demonstrating that developed formulation had a greater oral bioavailability. The RXN LSC tablets showed longer bleeding times and higher rates of platelet aggregation than RXN API. Thus, RXN LSC tablets can be considered a facile, scalable technology.


Asunto(s)
Productos Biológicos , Animales , Ratas , Rivaroxabán , Polietilenglicoles , Disponibilidad Biológica , Excipientes , Ratas Wistar
7.
AAPS PharmSciTech ; 24(6): 147, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37380851

RESUMEN

The current research aims to develop and evaluate chitosan-PLGA biocomposite scaffolds in combination with quercetin liposomes to accomplish the desired impact in oral lesions where pharmacotherapeutic agent treatment through circulation could only reach the low content at the target. Optimization of quercetin-loaded liposomes was carried out using 32 factorial design. The preparation of porous scaffolds comprising produced quercetin-loaded liposomes by thin-film method was carried out in the current study using a unique strategy combining solvent casting and gas foaming procedures. The prepared scaffolds were tested for physicochemical properties, in vitro quercetin release study, ex vivo drug permeation and retention research using goat mucosa, antibacterial activity, and cell migration studies on fibroblast L929 cell lines. Improved cell growth and migration were seen in the order control < liposomes < proposed system. The proposed system has been examined for its biological and physicochemical features, and it has the potential to be utilized as an efficient therapy for oral lesions.


Asunto(s)
Quitosano , Animales , Liposomas , Quercetina/farmacología , Antibacterianos/farmacología , Línea Celular , Cabras
8.
PLoS Pathog ; 16(9): e1008920, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32997730

RESUMEN

The virions of enteroviruses such as poliovirus undergo a global conformational change after binding to the cellular receptor, characterized by a 4% expansion, and by the opening of holes at the two and quasi-three-fold symmetry axes of the capsid. The resultant particle is called a 135S particle or A-particle and is thought to be on the pathway to a productive infection. Previously published studies have concluded that the membrane-interactive peptides, namely VP4 and the N-terminus of VP1, are irreversibly externalized in the 135S particle. However, using established protocols to produce the 135S particle, and single particle cryo-electron microscopy methods, we have identified at least two unique states that we call the early and late 135S particle. Surprisingly, only in the "late" 135S particles have detectable levels of the VP1 N-terminus been trapped outside the capsid. Moreover, we observe a distinct density inside the capsid that can be accounted for by VP4 that remains associated with the genome. Taken together our results conclusively demonstrate that the 135S particle is not a unique conformation, but rather a family of conformations that could exist simultaneously.


Asunto(s)
Cápside/ultraestructura , Poliomielitis/metabolismo , ARN Viral/ultraestructura , Virión/ultraestructura , Cápside/metabolismo , Proteínas de la Cápside/metabolismo , Microscopía por Crioelectrón , Humanos , Modelos Moleculares , ARN Viral/metabolismo , Receptores Virales/metabolismo , Virión/metabolismo , Internalización del Virus
9.
Bioorg Med Chem ; 56: 116588, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35030421

RESUMEN

Membrane permeability plays an important role in oral drug absorption. Caco-2 and Madin-Darby Canine Kidney (MDCK) cell culture systems have been widely used for assessing intestinal permeability. Since most drugs are absorbed passively, Parallel Artificial Membrane Permeability Assay (PAMPA) has gained popularity as a low-cost and high-throughput method in early drug discovery when compared to high-cost, labor intensive cell-based assays. At the National Center for Advancing Translational Sciences (NCATS), PAMPA pH 5 is employed as one of the Tier I absorption, distribution, metabolism, and elimination (ADME) assays. In this study, we have developed a quantitative structure activity relationship (QSAR) model using our ∼6500 compound PAMPA pH 5 permeability dataset. Along with ensemble decision tree-based methods such as Random Forest and eXtreme Gradient Boosting, we employed deep neural network and a graph convolutional neural network to model PAMPA pH 5 permeability. The classification models trained on a balanced training set provided accuracies ranging from 71% to 78% on the external set. Of the four classifiers, the graph convolutional neural network that directly operates on molecular graphs offered the best classification performance. Additionally, an ∼85% correlation was obtained between PAMPA pH 5 permeability and in vivo oral bioavailability in mice and rats. These results suggest that data from this assay (experimental or predicted) can be used to rank-order compounds for preclinical in vivo testing with a high degree of confidence, reducing cost and attrition as well as accelerating the drug discovery process. Additionally, experimental data for 486 compounds (PubChem AID: 1645871) and the best models have been made publicly available (https://opendata.ncats.nih.gov/adme/).


Asunto(s)
Betametasona/farmacocinética , Dexametasona/farmacocinética , Ranitidina/farmacocinética , Verapamilo/farmacocinética , Administración Oral , Animales , Betametasona/administración & dosificación , Disponibilidad Biológica , Células CACO-2 , Permeabilidad de la Membrana Celular/efectos de los fármacos , Células Cultivadas , Dexametasona/administración & dosificación , Perros , Relación Dosis-Respuesta a Droga , Humanos , Concentración de Iones de Hidrógeno , Células de Riñón Canino Madin Darby , Ratones , Estructura Molecular , Redes Neurales de la Computación , Ranitidina/administración & dosificación , Ratas , Relación Estructura-Actividad , Verapamilo/administración & dosificación
10.
Arch Toxicol ; 96(7): 1975-1987, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35435491

RESUMEN

Currently, approximately 80,000 chemicals are used in commerce. Most have little-to-no toxicity information. The U.S. Toxicology in the 21st Century (Tox21) program has conducted a battery of in vitro assays using a quantitative high-throughput screening (qHTS) platform to gain toxicity information on environmental chemicals. Due to technical challenges, standard methods for providing xenobiotic metabolism could not be applied to qHTS assays. To address this limitation, we screened the Tox21 10,000-compound (10K) library, with concentrations ranging from 2.8 nM to 92 µM, using a p53 beta-lactamase reporter gene assay (p53-bla) alone or with rat liver microsomes (RLM) or human liver microsomes (HLM) supplemented with NADPH, to identify compounds that induce p53 signaling after biotransformation. Two hundred and seventy-eight compounds were identified as active under any of these three conditions. Of these 278 compounds, 73 gave more potent responses in the p53-bla assay with RLM, and 2 were more potent in the p53-bla assay with HLM compared with the responses they generated in the p53-bla assay without microsomes. To confirm the role of metabolism in the differential responses, we re-tested these 75 compounds in the absence of NADPH or with heat-attenuated microsomes. Forty-four compounds treated with RLM, but none with HLM, became less potent under these conditions, confirming the role of RLM in metabolic activation. Further evidence of biotransformation was obtained by measuring the half-life of the parent compounds in the presence of microsomes. Together, the data support the use of RLM in qHTS for identifying chemicals requiring biotransformation to induce biological responses.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento , Proteína p53 Supresora de Tumor , Activación Metabólica , Animales , Ensayos Analíticos de Alto Rendimiento/métodos , Microsomas Hepáticos , NADP , Ratas , Transducción de Señal
11.
J Microencapsul ; 39(1): 1-24, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34825627

RESUMEN

AIM: In the current study, efforts are being made to prepare Inhalable Silibinin loaded solid lipid nanoparticles (SLNs) with narrow size distribution with improved bioavailability. METHODS: SLNs were formulated by high shear homogenisation method SLNs were characterised, including Differential Scanning Calorimetry (DSC), Fourier transform infra-red spectroscopy (FTIR), particle size analysis, entrapment efficiency with Aerodynamic behaviour. The MTT assay was performed against A549 cell line, to measure their anticancer cell activity with In vivo study. RESULTS: Optimized formulation exhibited spherical surface with a mean particle size of 221 ± 1.251 nm, PI of 0.121 ± 0.081, zeta potential of -4.12 ± 0.744. Aerodynamic behaviour such as Mass median aerodynamic diameter (MMAD) and Geometric size distribution (GSD) were found to be 5.487 ± 0.072 and 2.321 ± 0.141 respectively proved formulation is suitable for inhalation. In vitro cellular efficacy against A549 cells, revealed that the optimised formulations were more effective and potent. CONCLUSION: The Inhalable SLNs approach was successfully engineered and administered to the lungs safely without causing any problems.


Asunto(s)
Lípidos , Nanopartículas , Portadores de Fármacos , Liposomas , Pulmón , Tamaño de la Partícula , Silibina
12.
Drug Metab Dispos ; 49(9): 822-832, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34183376

RESUMEN

Cytochrome P450 enzymes are responsible for the metabolism of >75% of marketed drugs, making it essential to identify the contributions of individual cytochromes P450 to the total clearance of a new candidate drug. Overreliance on one cytochrome P450 for clearance levies a high risk of drug-drug interactions; and considering that several human cytochrome P450 enzymes are polymorphic, it can also lead to highly variable pharmacokinetics in the clinic. Thus, it would be advantageous to understand the likelihood of new chemical entities to interact with the major cytochrome P450 enzymes at an early stage in the drug discovery process. Typical screening assays using human liver microsomes do not provide sufficient information to distinguish the specific cytochromes P450 responsible for clearance. In this regard, we experimentally assessed the metabolic stability of ∼5000 compounds for the three most prominent xenobiotic metabolizing human cytochromes P450, i.e., CYP2C9, CYP2D6, and CYP3A4, and used the data sets to develop quantitative structure-activity relationship models for the prediction of high-clearance substrates for these enzymes. Screening library included the NCATS Pharmaceutical Collection, comprising clinically approved low-molecular-weight compounds, and an annotated library consisting of drug-like compounds. To identify inhibitors, the library was screened against a luminescence-based cytochrome P450 inhibition assay; and through crossreferencing hits from the two assays, we were able to distinguish substrates and inhibitors of these enzymes. The best substrate and inhibitor models (balanced accuracies ∼0.7), as well as the data used to develop these models, have been made publicly available (https://opendata.ncats.nih.gov/adme) to advance drug discovery across all research groups. SIGNIFICANCE STATEMENT: In drug discovery and development, drug candidates with indiscriminate cytochrome P450 metabolic profiles are considered advantageous, since they provide less risk of potential issues with cytochrome P450 polymorphisms and drug-drug interactions. This study developed robust substrate and inhibitor quantitative structure-activity relationship models for the three major xenobiotic metabolizing cytochromes P450, i.e., CYP2C9, CYP2D6, and CYP3A4. The use of these models early in drug discovery will enable project teams to strategize or pivot when necessary, thereby accelerating drug discovery research.


Asunto(s)
Citocromo P-450 CYP2C9/metabolismo , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A/metabolismo , Desarrollo de Medicamentos/métodos , Inhibidores Enzimáticos , Biocatálisis , Descubrimiento de Drogas/métodos , Interacciones Farmacológicas , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacocinética , Humanos , Inactivación Metabólica , Tasa de Depuración Metabólica , Relación Estructura-Actividad Cuantitativa
13.
Bioorg Med Chem Lett ; 40: 127906, 2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-33689873

RESUMEN

Zika virus has emerged as a potential threat to human health globally. A previous drug repurposing screen identified the approved anthelminthic drug niclosamide as a small molecule inhibitor of Zika virus infection. However, as antihelminthic drugs are generally designed to have low absorption when dosed orally, the very limited bioavailability of niclosamide will likely hinder its potential direct repurposing as an antiviral medication. Here, we conducted SAR studies focusing on the anilide and salicylic acid regions of niclosamide to improve physicochemical properties such as microsomal metabolic stability, permeability and solubility. We found that the 5-bromo substitution in the salicylic acid region retains potency while providing better drug-like properties. Other modifications in the anilide region with 2'-OMe and 2'-H substitutions were also advantageous. We found that the 4'-NO2 substituent can be replaced with a 4'-CN or 4'-CF3 substituents. Together, these modifications provide a basis for optimizing the structure of niclosamide to improve systemic exposure for application of niclosamide analogs as drug lead candidates for treating Zika and other viral infections. Indeed, key analogs were also able to rescue cells from the cytopathic effect of SARS-CoV-2 infection, indicating relevance for therapeutic strategies targeting the COVID-19 pandemic.


Asunto(s)
Antivirales/farmacología , Niclosamida/análogos & derivados , Niclosamida/farmacología , SARS-CoV-2/efectos de los fármacos , Virus Zika/efectos de los fármacos , Animales , Antivirales/síntesis química , Antivirales/metabolismo , Sitios de Unión , Chlorocebus aethiops , Estabilidad de Medicamentos , Humanos , Pruebas de Sensibilidad Microbiana , Microsomas Hepáticos/metabolismo , Simulación del Acoplamiento Molecular , Estructura Molecular , Niclosamida/metabolismo , Unión Proteica , Ratas , Serina Endopeptidasas/química , Serina Endopeptidasas/metabolismo , Relación Estructura-Actividad , Células Vero , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/metabolismo , Proteínas Virales/química , Proteínas Virales/metabolismo
14.
Br J Neurosurg ; 35(2): 181-185, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33764256

RESUMEN

INTRODUCTION: Evidence is emerging, suggesting a significant drop in hospital referrals and attendances for various medical conditions due to the COVID-19 pandemic. With the implementation of lockdown rules, road traffic and outdoor activities were expected to drop, thereby reducing the number of high-energy spinal injuries. Critical non-traumatic spinal conditions like spinal tumours, infections, or compressive pathologies, however, should continue to present as before. We assessed all acute spinal referrals to our tertiary spine unit comparing with the acute activity for a similar time frame in the previous year. The aim was to identify any variance in the acute spinal activity, explain reasons for the discrepancy and identify any learning points. MATERIALS: All acute referrals to our tertiary spinal surgery unit made from 01 February 2020 to 30 April 2020 were evaluated. Similar data from the preceding year, i.e. 2019 was evaluated for comparison. Data were analysed for qualitative or quantitative changes in the referral pattern and their subsequent management outcomes. RESULTS: Spinal referral numbers reduced by 46.05% during the time frame of February-April 2020 when compared to the same period in 2019 (p < 0.017). Similarly, numbers of high-energy traumatic presentations reduced by 72% (p < 0.002). Referrals for critical spinal conditions declined by two-thirds for spinal infections and more than a third for spinal tumours. Emergency surgical workload waned by 27%, especially more so during the six-week lockdown duration. CONCLUSION: Reduction in spinal activity, even for critical spinal conditions, during the pandemic is likely due to a combination of factors like patient behaviour, fear of contracting COVID-19 infection during hospital visit, self-isolation advice, availability of a senior decision maker on the frontlines, and changes in healthcare service provisions. The health crisis may provide an opportunity for optimisation of spinal healthcare services both at the referring hospital and at the tertiary centre.


Asunto(s)
COVID-19 , Pandemias , Control de Enfermedades Transmisibles , Humanos , Derivación y Consulta , SARS-CoV-2 , Reino Unido/epidemiología
15.
AAPS PharmSciTech ; 22(6): 216, 2021 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-34386888

RESUMEN

5-Fluorouracil (5-FU) is the most preferred chemotherapeutic agent in the management of colon cancer but is associated with poor therapeutic efficacy and lack of site specificity. Hence, it was aimed to employ Eudragit S100 surface engineered 5-FU nanostructured lipid carriers for the spatial and temporal release of the drug for the treatment of colon cancer. Hot high-pressure homogenization (HPH) technique was employed in the preparation of 5-FU-NLCs. The optimization of 5-FU-NLCs was performed using a Quality by Design (QbD) approach. A 32 factorial design was employed wherein the relationship between independent variables [amount of oleic acid (X1) and concentration of Tween®80 (X2)] and dependent variables [particle size (Y1) and % entrapment efficiency (Y2)] was studied. Optimized 5-FU-NLCs were surface treated to obtain Eudragit S100-coated 5-FU-NLCs (EU-5-FU-NLCs). The evaluation parameters for 5-FU-NLCs and EU-5-FU-NLCs included surface morphology, particle size, PDI, and zeta potential. In vitro release from EU-5-FU-NLCs revealed a selective and controlled 5-FU release in the colonic region for 24 h. In vitro cytotoxicity (MTT assay) was performed against Caco-2 cancer cells, wherein EU-5-FU-NLCs exhibited a 2-fold greater cytotoxic potential in comparison to a 5-FU solution (5-FU-DS). Oral administration of EU-5-FU-NLCs in Albino Wistar rats depicted a higher Cmax (2.54 folds) and AUC (11 folds) as well as prolonged Tmax (16 folds) and MRT (4.32 folds) compared to 5-FU-DS confirming higher bioavailability along with the spatial and temporal release in the colonic region. Thus, a multifaceted strategy involving abridgement of nanotechnology along with surface engineering is introduced for effective chemotherapy of colon cancer via oral administration of 5-FU with uncompromised safety and higher efficacy.Graphical abstract.


Asunto(s)
Neoplasias del Colon , Portadores de Fármacos , Nanoestructuras , Ácidos Polimetacrílicos , Animales , Células CACO-2 , Colon , Neoplasias del Colon/tratamiento farmacológico , Fluorouracilo , Humanos , Lípidos , Tamaño de la Partícula , Ratas
16.
AAPS PharmSciTech ; 22(8): 257, 2021 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-34676463

RESUMEN

Ticagrelor (TG) suffers from low peroral bioabsorption (36%) due to P-gp efflux and poor solubility (10 µg/mL). TG solid dispersion adsorbates (TG-SDAs) were formulated using an amalgamation of solid dispersion and melt adsorption techniques which were simple, economic, scalable, and solvent-free. FTIR indicated no incompatibility between drug and excipients. DSC, XRD, and SEM suggested a reduction in TG crystallinity. Q30min from TG-SUSP and TG-conventional tablets was only 2.30% and 6.59% respectively whereas TG-SDA-based tablets exhibited a significantly higher drug release of 86.47%. Caco-2 permeability studies showed 3.83-fold higher permeability of TG from TG-SDAs. TG-SDA-based tablets exhibited relative bioavailability of 748.53% and 153.43% compared to TG-SUSP and TG-conventional tablets respectively in rats. TG-SDA-based tablets were devoid of any cytotoxicity as indicated by MTT assay and exhibited better antiplatelet activity in rats. Enhanced oral bioavailability of TG-SDAs can be attributed to inhibition of P-gp efflux by PEG 4000, increased wettability, and reduced crystallinity of drug leading to improved drug solubility and dissolution. Improved bioabsorption results in a reduction of dose, cost of therapy as well as dose-related side effects. Thus, SDAs can be considered a promising and scalable approach for the improvement of dissolution rate and solubility of TG. TG-SDAs can be translated to an effective and safe dosage form, whereby its rapid onset of action promotes the prevention of heart attack, stroke, and related ill events in individuals with the acute coronary syndrome. However, scale-up, validation, and clinical-studies are necessary for confirmation of the proof-of-concept.


Asunto(s)
Química Farmacéutica , Excipientes , Adsorción , Animales , Disponibilidad Biológica , Células CACO-2 , Rastreo Diferencial de Calorimetría , Humanos , Ratas , Solubilidad , Comprimidos , Ticagrelor
17.
AAPS PharmSciTech ; 22(1): 28, 2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33404939

RESUMEN

Caffeic acid (CA), a hydroxycinnamic acid possessing a variety of pharmacological activities, has caused a growing interest for the treatment of hyperlipidemia and associated conditions. This work endeavored to develop a novel formulation of CA-Phospholipon® 90H complex (CA-PC) using a solvent evaporation method. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transform infrared spectrophotometry (FTIR), and powder X-ray powder diffraction (PXRD) was carried to confirm the formation of CA-PC. The CA-PC was functionally evaluated in terms of solubility, in vitro and ex vivo drug release, and in vivo bioavailability and efficacy studies. SEM, DSC, FTIR, and XRD studies indicated the physical interaction of CA with Phospholipon® 90H to form a complex. Dynamic light scattering (DLS) studies described particle size of 168 ± 3.9 nm with a monodisperse distribution (PDI 0.17) and a negative zeta-potential of - 16.6 ± 2.1 mV. The phospholipid complex significantly improved (4.2-fold) the solubility of CA. In vitro and ex vivo dissolution studies of the formulated CA-PC revealed a significantly higher release compared with the pure CA. The pharmacokinetic study of CA-PC in rats demonstrated a significant increase (4.79-fold) in oral bioavailability when compared with pure CA as well. Additionally, a significant improvement in serum lipid profile, serum liver biomarker enzyme levels and, restoration of hepatic tissue architecture to normal, in high-fat diet (HFD) induced hyperlipidemic model was obtained upon CA-PC administration when compared with pure CA. These findings indicated that CA-PC would serve as an effective and promising formulation for CA delivery with improved antihyperlipidemic and hepatoprotective activity.Graphical abstract.


Asunto(s)
Ácidos Cafeicos/química , Hígado/efectos de los fármacos , Fosfolípidos/química , Administración Oral , Animales , Disponibilidad Biológica , Ácidos Cafeicos/farmacología , Rastreo Diferencial de Calorimetría , Liberación de Fármacos , Hipolipemiantes/farmacología , Masculino , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Fosfolípidos/farmacología , Polvos , Ratas , Ratas Sprague-Dawley , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X
18.
Curr Opin Anaesthesiol ; 34(2): 161-167, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33630774

RESUMEN

PURPOSE OF REVIEW: Healthcare is rapidly evolving toward value-focused objectives, integrating outcomes and cost instead of simply volume. Concepts pertaining to Enhanced Recovery After Surgery (ERAS), Lean, and claims-based risk-adjusted databases can be used to optimize value, but the application of Lean principles and risk-adjusted outcomes is poorly described in perioperative medicine in perioperative medicine. RECENT FINDINGS: Lean management and process optimization tools allow the consistent application of a perioperative medical framework of ERAS to improve outcomes. Vizient risk-stratified outcomes are often used by hospitals to measure and compare quality. SUMMARY: Understanding administrative databases and Lean concepts for change management will allow the perioperative physician to better align medical concepts with health system tools for improving quality and reducing cost.


Asunto(s)
Recuperación Mejorada Después de la Cirugía , Humanos , Atención Perioperativa
19.
AAPS PharmSciTech ; 21(7): 284, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-33058071

RESUMEN

Curcumin is a unique molecule naturally obtained from rhizomes of Curcuma longa. Curcumin has been reported to act on diverse molecular targets like receptors, enzymes, and co-factors; regulate different cellular signaling pathways; and modulate gene expression. It suppresses expression of main inflammatory mediators like interleukins, tumor necrosis factor, and nuclear factor κB which are involved in the regulation of genes causing inflammation in most skin disorders. The topical delivery of curcumin seems to be more advantageous in providing a localized effect in skin diseases. However, its low aqueous solubility, poor skin permeation, and degradation hinder its application for commercial use despite its enormous potential. Lipid-based nanocarrier systems including liposomes, niosomes, solid lipid nanoparticles, nanostructured lipid carriers, lyotropic liquid crystal nanoparticles, lipospheres, and lipid nanocapsules have found potential as carriers to overcome the issues associated with conventional topical dosage forms. Nano-size, lipophilic nature, viscoelastic properties, and occlusive effect of lipid nanocarriers provide high drug loading, hydration of skin, stability, enhanced permeation through the stratum corneum, and slow release of curcumin in the targeted skin layers. This review particularly focuses on the application of lipid nanocarriers for the topical delivery of curcumin in the treatment of various skin diseases. Furthermore, preclinical studies and patents have also indicated the emerging commercialization potential of curcumin-loaded lipid nanocarriers for effective drug delivery in skin disorders. Graphical Abstract.


Asunto(s)
Curcumina/administración & dosificación , Curcumina/uso terapéutico , Enfermedades de la Piel/tratamiento farmacológico , Administración Tópica , Animales , Portadores de Fármacos , Humanos , Nanopartículas , Nanoestructuras , Absorción Cutánea
20.
EMBO Rep ; 18(11): 2051-2066, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28893863

RESUMEN

Endocytic processes are facilitated by both curvature-generating BAR-domain proteins and the coordinated polymerization of actin filaments. Under physiological conditions, the N-BAR protein Bin1 has been shown to sense and curve membranes in a variety of cellular processes. Recent studies have identified Bin1 as a risk factor for Alzheimer's disease, although its possible pathological function in neurodegeneration is currently unknown. Here, we report that Bin1 not only shapes membranes, but is also directly involved in actin binding through its BAR domain. We observed a moderate actin bundling activity by human Bin1 and describe its ability to stabilize actin filaments against depolymerization. Moreover, Bin1 is also involved in stabilizing tau-induced actin bundles, which are neuropathological hallmarks of Alzheimer's disease. We also provide evidence for this effect in vivo, where we observed that downregulation of Bin1 in a Drosophila model of tauopathy significantly reduces the appearance of tau-induced actin inclusions. Together, these findings reveal the ability of Bin1 to modify actin dynamics and provide a possible mechanistic connection between Bin1 and tau-induced pathobiological changes of the actin cytoskeleton.


Asunto(s)
Actinas/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Portadoras/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas Nucleares/genética , Tauopatías/genética , Factores de Transcripción/genética , Proteínas Supresoras de Tumor/genética , Proteínas tau/genética , Citoesqueleto de Actina/genética , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Sitios de Unión , Proteínas Portadoras/metabolismo , Clonación Molecular , Modelos Animales de Enfermedad , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Regulación de la Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Humanos , Proteínas Nucleares/metabolismo , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tauopatías/metabolismo , Tauopatías/patología , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Proteínas tau/metabolismo
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