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1.
Front Med (Lausanne) ; 11: 1386979, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737759

RESUMO

Primary vitreoretinal lymphoma (PVRL) is often associated with central nervous system involvement, contributing to a heightened mortality rate, thus imaging features that are characteristic enough to be potential biomarkers of PVRL are important, either in diagnosis or in assessment of disease activity. This report details the case of a 68-year-old male who presented with blurred vision in both eyes persisting for 2 months. Fundus examination demonstrated vitreous opacity and multiple subretinal yellow nodular lesions of varying sizes in the peripheral fundus of both eyes. Multiple vertical hyperreflective lesions in the neural retina of posterior pole, indistinct outer retina borders in the fovea, and hyperreflective lesions in the sub-retinal pigment epithelium (RPE) space of the peripheral retina were demonstrated on swept-source optical coherence tomography (SS-OCT) of the left eye. Hyperflow signals corresponding to the vertical hyperreflective lesions were detected on swept-source optical coherence tomography angiography (SS-OCTA) images of retinal deep capillary plexus (DCP) layer. Notably, the hyperflow signals, precisely located around retinal vessels from the nerve fiber layer to the outer plexiform layer, were postulated to stem from the dilation of infiltrated retinal vessels. Vitreous pathological results of the left eye confirmed the diagnosis of PVRL. Treatments with intravitreal methotrexate injections led to a marked improvement of best-corrected visual acuity (BCVA) and regression of the hyperflow microinfiltration lesions demonstrated on SS-OCTA. In conclusion, SS-OCTA effectively delineated the vertical hyperreflective lesions and corresponding hyperflow signals in the posterior pole macular region of a patient with PVRL. These lesions significantly diminished following intravitreal methotrexate injections. We speculated that the specific hyperflow signals on SS-OCTA could act as a potential biomarker of PVRL, and SS-OCTA holds promise in facilitating early diagnosis and monitoring therapeutic responses in PVRL cases.

2.
Mol Pharm ; 21(4): 1933-1941, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38502549

RESUMO

Islatravir, a highly potent nucleoside reverse transcriptase translocation inhibitor (NRTTI) for the treatment of HIV, has great potential to be formulated as ethylene-vinyl acetate (EVA) copolymer-based implants via hot melt extrusion. The crystallinity of EVA determines its physical and rheological properties and may impact the drug-eluting implant performance. Herein, we describe the systematic analysis of factors affecting the EVA crystallinity in islatravir implants. Differential scanning calorimetry (DSC) on EVA and solid-state NMR revealed drug loading promoted EVA crystallization, whereas BaSO4 loading had negligible impact on EVA crystallinity. The sterilization through γ-irradiation appeared to significantly impact the EVA crystallinity and surface characteristics of the implants. Furthermore, DSC analysis of thin implant slices prepared with an ultramicrotome indicated that the surface layer of the implant was more crystalline than the core. These findings provide critical insights into factors affecting the crystallinity, mechanical properties, and physicochemical properties of the EVA polymer matrix of extruded islatravir implants.


Assuntos
Desoxiadenosinas , Etilenos , Polivinil , Compostos de Vinila , Polivinil/química
3.
J Multidiscip Healthc ; 16: 1883-1888, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37425248

RESUMO

Objective: To evaluate the effect of emotional ABC theory on anxiety and depression in young patients with breast cancer. Methods: A total of 200 eligible young patients with breast cancer were randomly divided into control group (N = 100) and experimental group (N = 100). The control group received routine treatment, while the experimental group received emotional ABC theory intervention at the same time. Results: The Self Rating Anxiety Scale (SAS) and Self Rating Depression Scale (SDS) scores of the two groups were observed before and after nursing. There was no significant difference between the two groups before nursing (P > 0.05), but there was significant difference between the two groups after nursing, the control group was significantly higher than the experimental group (P < 0.05). The satisfaction degree of the control group was significantly lower than that of the experimental group (P < 0.05). Conclusion: Young patients with breast cancer using emotional ABC theory can effectively improve negative emotions, clinical can promote the nursing program.

4.
Mol Pharm ; 20(8): 4268-4276, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37382286

RESUMO

Particles in biopharmaceutical products present high risks due to their detrimental impacts on product quality and safety. Identification and quantification of particles in drug products are important to understand particle formation mechanisms, which can help develop control strategies for particle formation during the formulation development and manufacturing process. However, existing analytical techniques such as microflow imaging and light obscuration measurement lack the sensitivity and resolution to detect particles with sizes smaller than 2 µm. More importantly, these techniques are not able to provide chemical information to determine particle composition. In this work, we overcome these challenges by applying the stimulated Raman scattering (SRS) microscopy technique to monitor the C-H Raman stretching modes of the proteinaceous particles and silicone oil droplets formed in the prefilled syringe barrel. By comparing the relative signal intensity and spectral features of each component, most particles can be classified as protein-silicone oil aggregates. We further show that morphological features are poor indicators of particle composition. Our method has the capability to quantify aggregation in protein therapeutics with chemical and spatial information in a label-free manner, potentially allowing high throughput screening or investigation of aggregation mechanisms.


Assuntos
Agregados Proteicos , Óleos de Silicone , Óleos de Silicone/química , Análise Espectral Raman , Proteínas/química , Microscopia , Tamanho da Partícula
5.
J Pharm Sci ; 111(12): 3191-3194, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36404459

RESUMO

Silicone oil is often applied to the inner surface of glass syringes and cartridges to reduce friction between the glass surface and elastomeric plunger stopper. This oil can appear as intrinsic and non-proteinaceous particles in the ejected fluid or drug product. Limited data is available to understand the impact of age (time between syringe manufacture and filling) on silicone oil migration into the drug product. This study compares subvisible particle count and extrusion force of siliconized syringes from two different manufacturers stored at ambient condition for 2-3 (fresh syringes) and 13-14 (aged syringes) months then filled and placed at 40°C for an additional three months. The fresh syringes exhibit a 2.5-fold increase in subvisible particle count compared to those aged ones. Moreover, the fresh syringes exhibit up to a 2-fold increase in extrusion force. These findings suggest the degree and amount of silicone oil migration is influenced by the time in storage of the glass syringe prior to filling. This rapid communication highlights syringe storage time prior to filling as a factor to be considered during development.


Assuntos
Óleos de Silicone , Seringas , Proteínas , Vidro
6.
Mol Pharm ; 19(9): 3267-3278, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35917158

RESUMO

Antimicrobial preservatives are used as functional excipients in multidose formulations of biological therapeutics to destroy or inhibit the growth of microbial contaminants, which may be introduced by repeatedly administering doses. Antimicrobial agents can also induce the biophysical instability of proteins and peptides, which presents a challenge in optimizing the drug product formulation. Elucidating the structural basis for aggregation aids in understanding the underlying mechanism and can offer valuable knowledge and rationale for designing drug substances and drug products; however, this remains largely unexplored due to the lack of high-resolution characterization. In this work, we utilize solution nuclear magnetic resonance (NMR) as an advanced biophysical tool to study an acylated 31-residue peptide, acyl-peptide A, and its interaction with commonly used antimicrobial agents, benzyl alcohol and m-cresol. Our results suggest that acyl-peptide A forms soluble octamers in the aqueous solution, which tumble slowly due to an increased molecular weight as measured by diffusion ordered spectroscopy and 1H relaxation measurement. The addition of benzyl alcohol does not induce aggregation of acyl-peptide A and has no chemical shift perturbation in 1H-1H NOESY spectra, suggesting no detectable interaction with the peptide. In contrast, the addition of 1% (w/v) m-cresol results in insoluble aggregates composed of 25% (w/w) peptides after a 24-hour incubation at room temperature as quantified by 1H NMR. Interestingly, 1H-13C heteronuclear single-quantum coherence and 1H-1H total correlation experiment spectroscopy have identified m-cresol and peptide interactions at specific residues, including Met, Lys, Glu, and Gln, suggesting that there may be a combination of hydrophobic, hydrogen bonding, and electrostatic interactions with m-cresol driving this phenomenon. These site-specific interactions have promoted the formation of higher-order oligomerization such as dimers and trimers of octamers, eventually resulting in insoluble aggregates. Our study has elucidated a structural basis of m-cresol-induced self-association that can inform the optimized design of drug substances and products. Moreover, it has demonstrated solution NMR as a high-resolution tool to investigate the structure and dynamics of biological drug products and provide an understanding of excipient-induced peptide and protein aggregation.


Assuntos
Anti-Infecciosos , Excipientes , Antibacterianos , Anti-Infecciosos/química , Álcool Benzílico/química , Excipientes/química , Peptídeos , Conservantes Farmacêuticos/química
7.
Invest Ophthalmol Vis Sci ; 63(8): 2, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35802383

RESUMO

Purpose: Scleral hypoxia is a key factor that induces hypoxia-inducible factor-1α (HIF-1α) upregulation, and this response contributes to myopia progression. Currently, we aim to determine if the different HIF subtypes, including HIF-1α and HIF-2α, mediate hypoxia-induced myopia development through promoting scleral MMP-2 expression and collagen degradation. Methods: Our study included: (1) time-course of scleral HIF-2α, MMP-2, and COL1α1 expression during form-deprivation myopia (FDM) development was determined in C57BL/6J mice. (2) The effect of silencing either HIF-1Α or HIF-2A on hypoxia-induced alterations in MMP-2 expression was analyzed in cultured human scleral fibroblasts (HSFs) under a hypoxic condition (i.e. 1% oxygen). (3) To knock-down either HIF-1α or HIF-2α expression in the sclera, we performed Sub-Tenon's capsule injection of an adeno-associated virus (AAV)8-packaged Cre overexpression vector (AAV8-Cre) in HIF-1αfl/fl or HIF-2αfl/fl mice. HIF-1α, HIF-2α, MMP-2, and COL1α1 expression were analyzed by Western blot or quantitative real-time PCR (qRT-PCR). In addition, the effects of scleral HIF-2α knock-down on normal refractive development and FDM development were evaluated. Results: The time-dependent increases in scleral HIF-2α mimicked the HIF-1α expression profiles as we previously described. Hypoxia significantly promoted MMP-2 expression in HSFs, and this upregulation was solely alleviated by HIF-2A rather than HIF-1A silencing. Scleral HIF-2α knockdown significantly inhibited form-deprivation (FD)-induced MMP-2 upregulation and declines in COL1α1 accumulation and myopia development. Although scleral HIF-1α knockdown also significantly suppressed FD-induced declines in COL1α1 accumulation, it did not abrogate scleral MMP-2 upregulation. Conclusions: HIF-2α rather than HIF-1α induces myopia development through upregulating MMP-2 and promoting collagen degradation in the sclera.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Metaloproteinase 2 da Matriz , Miopia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Colágeno/metabolismo , Hipóxia/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miopia/genética , Miopia/metabolismo , Esclera/metabolismo , Regulação para Cima
8.
Biosci Rep ; 42(5)2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35438133

RESUMO

The primary objective of this study was to construct an immune-related long noncoding RNAs (IRLs) classifier to precisely predict the prognosis and immunotherapy response of patients with thymic epithelial tumors (TET). Based on univariable Cox regression analysis and Lasso regression, six prognosis-related IRLs (AC004466.3, AC138207.2, AC148477.2, AL450270.1, HOXB-AS1 and SNHG8) were selected to build an IRL classifier. Importantly, results of qRT-PCR validated that higher expression levels of AC138207.2, AC148477.2, AL450270.1 and SNHG8 as well as lower expression levels of AC004466.3, and HOXB-AS1 in TETs samples compared with normal controls. The IRL classifier could effectively classify patients into the low-risk and high-risk groups based on the different survival parameters. In terms of predictive ability and clinical utility, the IRL classifier was superior to Masaoka staging system. Additionally, IRL classifier is significantly associated with immune cells infiltration (dendritic cells, activated CD4 memory T cells and tumor-infiltrating lymphocyte (TIL), T cell subsets in particular), immune microenvironment (immune score and immune checkpoint inhibitors) and immunogenicity (TMB) in TETs, which hints that IRL classifier is tightly correlated with immune characteristics and might guide more effective immunotherapy strategies for TETs patients. Encouragingly, according to TIDE algorithm, there were more immunotherapy responders in the low-risk IRL subgroup and the IRL score was robustly negatively linked to the immunotherapeutic response. To sum up, the IRL classifier was established, which can be used to predict the prognosis, immune infiltration status, immunotherapy response in TETs patients, and may facilitate personalized counseling for immunotherapy.


Assuntos
Neoplasias Epiteliais e Glandulares , RNA Longo não Codificante , Biomarcadores Tumorais/genética , Humanos , Imunoterapia , Neoplasias Epiteliais e Glandulares/diagnóstico , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Epiteliais e Glandulares/terapia , RNA Longo não Codificante/genética , Neoplasias do Timo , Microambiente Tumoral/genética
9.
Mol Pharm ; 18(12): 4310-4321, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34761934

RESUMO

The introduction of solubilizing additives has historically been an attractive approach to address the ever-growing proportion of poorly water-soluble drug (PWSD) compounds within the modern drug discovery pipeline. Lipid-formulations, and more specifically micelle formulations, have garnered particular interest because of their simplicity, size, scalability, and avoidance of solid-state limitations. Although micelle formulations have been widely utilized, the molecular mechanism of drug solubilization in surfactant micelles is still poorly understood. In this study, a series of modern nuclear magnetic resonance (NMR) methods are utilized to gain a molecular-level understanding of intermolecular interactions and kinetics in a model system. This approach enabled the understanding of how a PWSD, 17ß-Estradiol (E2), solubilizes within a nonionic micelle system composed of polysorbate 80 (PS80). Based on one-dimensional (1D) 1H chemical shift differences of E2 in PS80 solutions, as well as intermolecular correlations established from 1D selective nuclear Overhauser effect (NOE) and two-dimensional NOE spectroscopy experiments, E2 was found to accumulate within the palisade layer of PS80 micelles. A potential hydrogen-bonding interaction between a hydroxyl group of E2 and a carbonyl group of PS80 alkane chains may allow for stabilizing E2-PS80 mixed micelles. Diffusion and relaxation NMR analysis and particle size measurements using dynamic light scattering indicate a slight increase in the micellar size with increasing degrees of supersaturation, resulting in slower mobility of the drug molecule. Based on these structural findings, a theoretical orientation model of E2 molecules with PS80 molecules was developed and validated by computational docking simulations.


Assuntos
Estradiol/química , Espectroscopia de Ressonância Magnética/métodos , Polissorbatos/química , Cristalização , Micelas , Simulação de Acoplamento Molecular , Tamanho da Partícula , Solubilidade
10.
Eur J Pharm Biopharm ; 165: 52-65, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33979662

RESUMO

Abiraterone is a poorly water-soluble drug used in the treatment of prostate cancer. In our previous study, we reported that KinetiSol® processed solid dispersions (KSDs) based on hydroxypropyl ß-cyclodextrin (HPBCD) showed improved dissolution and pharmacokinetics of abiraterone. However, the nature of abiraterone-HPBCD interaction within the KSDs or the effect of drug loading on the physicochemical properties and in vivo performance of HPBCD-based KSDs remain largely unknown. We hypothesize that KinetiSol technology can prepare abiraterone-HPBCD complexes within KSDs and that increasing the drug loading beyond an optimal point reduces the in vitro and in vivo performance of these KSDs. To confirm our hypothesis, we developed KSDs with 10-50% w/w drug loading and analyzed them using X-ray diffractometry and modulated differential scanning calorimetry. We found that KSDs containing 10-30% drug were amorphous. Interestingly, two-dimensional solid-state nuclear magnetic resonance and Raman spectroscopy indicated that the abiraterone-HPBCD complexes were formed. At elevated temperatures, the 10% and 20% drug-loaded KSDs were physically stable, while the 30% drug-loaded KSD showed recrystallization of abiraterone. In vitro dissolution and in vivo pharmacokinetic performances improved as the drug loading decreased; we attribute this to increased noncovalent interactions between abiraterone and HPBCD at lower drug loadings. Overall, the 10% drug loaded KSD showed a dissolution enhancement of 15.7-fold compared to crystalline abiraterone, and bioavailability enhancement of 3.9-fold compared to the commercial abiraterone acetate tablet Zytiga®. This study is first to confirm that KinetiSol, a high-energy, solvent-free technology, is capable of forming abiraterone-HPBCD complexes. Furthermore, in terms of in vitro and in vivo performance, a 10% drug load is optimal.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/química , Androstenos/farmacocinética , Composição de Medicamentos/métodos , Excipientes/química , Androstenos/química , Disponibilidade Biológica , Química Farmacêutica , Liberação Controlada de Fármacos
11.
Oxid Med Cell Longev ; 2021: 6667355, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33747349

RESUMO

We previously found that marine sponge-derived manoalide induced antiproliferation and apoptosis of oral cancer cells as well as reactive species generations probed by dichloro-dihydrofluorescein diacetate (DCFH-DA) and MitoSOX Red. However, the sources of cellular and mitochondrial redox stresses and the mutual interacting effects between these redox stresses and apoptosis remain unclear. To address this issue, we examined a panel of reactive species and used the inhibitors of cellular reactive species (N-acetylcysteine (NAC)), mitochondrial reactive species (MitoTEMPO), and apoptosis (Z-VAD-FMK; ZVAD) to explore their interactions in manoalide-treated oral cancer Ca9-22 and CAL 27 cells. Hydroxyl (˙OH), nitrogen dioxide (NO2˙), nitric oxide (˙NO), carbonate radical-anion (CO3 ˙-), peroxynitrite (ONOO-), and superoxide (O2 ˙-) were increased in oral cancer cells following manoalide treatments in terms of fluorescence staining and flow cytometry. Cellular reactive species (˙OH, NO2 ·, ˙NO, CO3 ˙-, and ONOO-) as well as cellular and mitochondrial reactive species (O2 ˙-) were induced in oral cancer cells following manoalide treatment for 6 h. NAC, MitoTEMPO, and ZVAD inhibit manoalide-induced apoptosis in terms of annexin V and pancaspase activity assays. Moreover, NAC inhibits mitochondrial reactive species and MitoTEMPO inhibits cellular reactive species, suggesting that cellular and mitochondrial reactive species can crosstalk to regulate each other. ZVAD shows suppressing effects on the generation of both cellular and mitochondrial reactive species. In conclusion, manoalide induces reciprocally activation between cellular and mitochondrial reactive species and apoptosis in oral cancer cells.


Assuntos
Apoptose/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Espécies Reativas de Oxigênio/metabolismo , Terpenos/farmacologia , Acetilcisteína/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Etídio/análogos & derivados , Etídio/metabolismo , Fluoresceínas/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Oligopeptídeos/farmacologia , Compostos Organofosforados/farmacologia , Fenantridinas/metabolismo , Piperidinas/farmacologia
12.
J Pharm Sci ; 110(3): 1292-1301, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33249049

RESUMO

Biophysical and biochemical instability of therapeutic proteins in the solution state may necessitate the development of products in the solid form, due to their enhanced stability. Lyophilization is a widely used method to ensure dry state stabilization of biological products. A commonly encountered issue is the pH shifts that can occur due to undesired crystallization of a buffer component, resulting in loss of protein activities. However, it is technically challenging to noninvasively investigate the physicochemical environment in the lyophile matrix. In this work, we demonstrate an approach based on solid-state NMR to investigate the microenvironmental acidity in lyophilized protein formulations, using histidine, a commonly used buffer agent, as a molecular probe. The solid-state acidity in the lyophilized matrix can be assessed by monitoring the chemical shift changes of histidine. The protonation and tautomeric states of histidine lyophilized at a range of pH values from 4.5 to 11.0 were identified from full 13C and 15N resonance assignments in one-dimensional and two-dimensional NMR experiments. The results demonstrated a pH-dependence of histidine chemical shift in the amorphous state. Moreover, we successfully applied this protocol to investigate the microenvironmental pH in lyophilized formulations of the HPV vaccine and lactate dehydrogenase protein.


Assuntos
Proteínas , Vacinas , Composição de Medicamentos , Liofilização , Espectroscopia de Ressonância Magnética
13.
Drug Deliv Transl Res ; 11(5): 2072-2084, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33151484

RESUMO

Rafoxanide (RAF) is a poorly water-soluble drug that forms a complex with povidone K25 (PVP) in a cosolvent system containing acetone and an alkaline aqueous medium. This study aims to investigate the impact of RAF-PVP complexation on in vitro and in vivo release of RAF. We prepared two RAF amorphous solid dispersions (ASDs) spray-dried from these two cosolvents. The first is a complexation-based spray-drying using a 70% 0.1 N NaOH solution with 30% acetone. The second is a traditional spray-dried formulation containing 80% acetone and 20% ethanol. Evidence from multiple solid-state characterization techniques indicated that ASDs spray-dried using both methods were amorphous. However, RAF ASDs based on drug-polymer complexation in the feed solution demonstrated not only faster drug release during dissolution testing but also higher in vivo absorption in an animal model. The improved RAF release in the complexation-based ASD is due to (1) high energy state of RAF owing to the amorphous form, (2) high pH in the microenvironment due to the ionized state of RAF and residual sodium hydroxide, (3) increased apparent solubility of RAF results from RAF-PVP complexation in dissolution media and biological media, and (4) improved wettability.


Assuntos
Polímeros , Povidona , Animais , Liberação Controlada de Fármacos , Polímeros/química , Povidona/química , Solubilidade , Água/química
14.
J Pharm Sci ; 110(2): 850-859, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32980392

RESUMO

New classes of therapeutic peptides are being developed to prosecute biological targets which have been inaccessible to other modalities. Higher potency and longer half-life peptides have given rise to multiuse injectable formulations that enable convenient, low volume, and self-administered dosing; however, inclusion of antimicrobial preservatives to meet bactericidal requirements can impact other attributes of peptide formulations. Peptide-preservative interactions influencing solution-phase self-association of a non-insulin, linear, palmitoylated 31 amino acid peptide and two structurally similar peptides were assessed via turbidity, intrinsic fluorescence shifts and quenching, isothermal titration calorimetry, and 1H NMR. Meta-cresol and phenol specifically interact with the peptide, result in increased hydrophobicity near the tryptophan residue, and induce conformational changes, while benzyl alcohol does not impact tryptophan fluorescence, demonstrate any interaction enthalpy, or induce conformational changes. These same trends did not hold true for the other palmitoylated peptides evaluated, reinforcing the impacts of unique peptide sequences. Importantly, the presence of benzyl alcohol does increase the physical stability and solubility of the linear, 31 amino acid peptide under salt stress. We report new insights into the physical interactions of peptides with antimicrobial excipients, demonstrating a reversible association phenomenon and highlighting practical implications for formulation design and excipient selection.


Assuntos
Anti-Infecciosos , Excipientes , Peptídeos , Conservantes Farmacêuticos , Solubilidade
15.
Mol Pharm ; 17(11): 4125-4140, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32965123

RESUMO

Enabling formulations are an attractive approach to increase the dissolution rate, solubility, and oral bioavailability of poorly soluble compounds. With the growing prevalence of poorly soluble drug compounds in the pharmaceutical pipeline, supersaturating drug delivery systems (SDDS), a subset of enabling formulations, have grown in popularity due to their properties allowing for drug concentrations greater than the corresponding crystalline solubility. However, the extent of supersaturation generated as the enabling formulation traverses the gastrointestinal (GI) tract is dynamic and poorly understood. The dynamic nature of supersaturation is a result of several competing kinetic processes such as dissolution, solubilization by formulation and endogenous surfactants, crystallization, and absorption. Ultimately, the free drug concentration, which is equivalent to the drug's inherent thermodynamic activity amid these kinetic processes, defines the true driving force for drug absorption. However, in cases where solubilizing agents are present (i.e., surfactants and bile salts), drug molecules may associate with colloidal nanoscale species, complicating drug activity determination. These nanoscale species can drift into the aqueous boundary layer (ABL), increasing the local API activity at the membrane surface, resulting in increased bioavailability. Herein, a novel approach was developed to accurately measure thermodynamic drug activity in complex media containing drug distributed in nanoparticulate species. This approach captures the influence of the ABL on the observed flux and, ultimately, the predicted unbound drug concentration. The results demonstrate that this approach can help to (1) measure the true extent of local supersaturation in complex systems containing solubilizing excipients and (2) elucidate the mechanisms by which colloidal aggregates can modulate the drug activity in solution and potentially enhance the flux observed across a membrane. The utilization of these techniques may provide development scientists with a strategy to evaluate formulation sensitivity to nanospeciation and allow formulators to maximize the driving force for absorption in a complex environment, perhaps enabling the development of dissolution methods with greater discrimination and correlation to pre-clinical and clinical data sets.


Assuntos
Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Estradiol/farmacocinética , Nanopartículas/química , Disponibilidade Biológica , Química Farmacêutica/métodos , Estradiol/química , Excipientes/química , Difusão Facilitada , Absorção Intestinal , Micelas , Polissorbatos/química , Solubilidade , Tensoativos/química , Termodinâmica
16.
Invest Ophthalmol Vis Sci ; 61(8): 44, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32725213

RESUMO

Purpose: Cyclic adenosine monophosphate (cAMP) and peroxisome proliferator-activated receptor alpha (PPARα) levels mediate extracellular matrix (ECM) changes by altering the levels of hypoxia-inducible factor 1-alpha (HIF-1α) in various tissues. We aimed to determine, in the sclera of guinea pigs, whether a prostanoid receptor (EP2)-linked cAMP modulation affects PPARα and HIF-1α signaling during myopia. Methods: Three-week-old guinea pigs (n = 20 in each group), were monocularly injected with either an EP2 agonist (butaprost 1 µmol/L/10 µmol/L), an antagonist (AH6809 10 µmol/L/30 µmol/L) or a vehicle solution for two weeks during normal ocular growth. Separate sets of animals received these injections and underwent form deprivation (FD) simultaneously. Refraction and axial length (AL) were measured at two weeks, followed by scleral tissue isolation for quantitative PCR (qPCR) analysis (n = 10) and cAMP detection (n = 10) using a radioimmunoassay. Results: Butaprost induced myopia development during normal ocular growth, with proportional increases in AL and cAMP levels. FD did not augment the magnitude of myopia or cAMP elevations in these agonist-injected eyes. AH6809 suppressed cAMP increases and myopia progression during FD, but had no effect in a normal visual environment. Of the diverse set of 27 genes related to cAMP, PPARα and HIF-1α signaling and ECM remodeling, butaprost differentially regulated 15 of them during myopia development. AH6809 injections during FD negated such differential gene expressions. Conclusion: EP2 agonism increased cAMP and HIF-1α signaling subsequent to declines in PPARα and RXR mRNA levels, which in turn decreased scleral fibrosis and promoted myopia. EP2 antagonism instead inhibited each of these responses. Our data suggest that EP2 suppression may sustain scleral ECM structure and inhibit myopia development.


Assuntos
Alprostadil/análogos & derivados , Matriz Extracelular , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Miopia Degenerativa , PPAR alfa/metabolismo , Receptores de Prostaglandina E Subtipo EP2 , Xantonas/farmacologia , Alprostadil/farmacologia , Animais , AMP Cíclico/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Cobaias , Miopia Degenerativa/etiologia , Miopia Degenerativa/metabolismo , Miopia Degenerativa/prevenção & controle , Antagonistas de Prostaglandina/farmacologia , Prostaglandinas E Sintéticas/farmacologia , Receptores de Prostaglandina E Subtipo EP2/agonistas , Receptores de Prostaglandina E Subtipo EP2/antagonistas & inibidores , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Transdução de Sinais
17.
Am J Pathol ; 190(9): 1888-1908, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32553806

RESUMO

Myopia is a leading cause of visual impairment worldwide. This sight-compromising condition is associated with scleral thinning, extracellular matrix remodeling, and inappropriate optical axial length elongation. Although macrophages are present in the sclera, their involvement in this condition is unknown. By using a form-deprivation myopia (FDM) mouse model, we found that both the scleral macrophage density and their matrix metalloproteinase-2 (MMP-2) expression levels increased in myopic eyes. Partial scleral macrophage depletion by clodronate shifted the refraction toward hyperopia in both the form-deprived and the untreated fellow eyes compared with their respective counterparts in the vehicle-injected control mice. However, this procedure did not alter susceptibility to FDM. FDM development was 59% less in the macrophage-specific Mmp2 deletion (LysMCreMmp-2fl/fl) mice than in their Cre-negative littermates (Mmp2fl/fl mice). Moreover, the expression of scleral C-C motif chemokine ligand-2 (CCL2), which is a potent monocyte chemoattractant recruiting monocytes to tissue sites, was increased during myopia progression. However, the increase in the density of scleral macrophages and myopia development were suppressed in fibroblast-specific Ccl2 deletion mice. These declines suggested that the increase in scleral macrophage density in myopic eyes stems from the up-regulation of scleral Ccl2 expression in fibroblasts, which, in turn, promotes monocytes recruitment. In summary, scleral monocyte-derived macrophages contribute to myopia development through enhancing MMP-2 expression in mice.


Assuntos
Macrófagos/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Miopia/enzimologia , Esclera/enzimologia , Esclera/patologia , Animais , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Miopia/patologia , Regulação para Cima
18.
Int J Antimicrob Agents ; 56(2): 106047, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32544568

RESUMO

Clonal complex 59 (CC59) is the dominant community-associated methicillin-resistant Staphylococcus aureus (MRSA) strain in Taiwan and includes the Asian-Pacific clone with Panton-Valentine leukocidin (PVL)-negative/staphylococcal cassette chromosome mec (SCCmec) IVg and the Taiwan clone characterised as PVL-positive/SCCmec V (5C2&5). Nevertheless, data on the evolutionary history of the two dominant CC59 MRSA clones in Taiwan are scarce. In this study, a total of 258 CC59 S. aureus strains from Taiwan were classified by multiple-locus variable-number tandem repeat analysis (MLVA), which revealed two major clusters (MT1 and MT2) with distinct mobile genetic elements (MGEs). However, sequencing and PCR mapping of the ß-lactamase-producing plasmid revealed no difference among all CC59 S. aureus strains. Bayesian evolutionary analysis of 18 of the CC59 S. aureus strains based on core genome alignment revealed two clades: (i) Clade A, which shared the samples with MT1, had the features of mainly harbouring gentamicin-resistant MES6272-2 or MES4578, φSA3 translocation in νSaß and SCCmec IVg; and (ii) Clade B, which shared the samples with MT2, had the features of mainly harbouring streptomycin-resistant MESPM1, PVL phage and SCCmec V (5C2&5). Based on the time-calibrated phylogenetic tree, the estimated time of divergence of the two clades was in the 1980s. These results suggest that the CC59 S. aureus progenitor acquired a ß-lactamase-producing plasmid and then developed the varied genetic backgrounds, which were associated with the acquisition and maintenance of distinct MGEs, leading to differences in antimicrobial susceptibility profiles and molecular virulence determinants.


Assuntos
Evolução Clonal , Elementos de DNA Transponíveis , Farmacorresistência Bacteriana Múltipla/genética , Ilhas Genômicas , Staphylococcus aureus Resistente à Meticilina/genética , Repetições Minissatélites , Antibacterianos/farmacologia , Toxinas Bacterianas/genética , Teorema de Bayes , Infecções Comunitárias Adquiridas/microbiologia , Exotoxinas/genética , Genoma Bacteriano , Humanos , Leucocidinas/genética , Staphylococcus aureus Resistente à Meticilina/classificação , Testes de Sensibilidade Microbiana , Filogenia , Prófagos/genética , Infecções Estafilocócicas/microbiologia , Taiwan , Fatores de Tempo , Fatores de Virulência/genética , beta-Lactamases/farmacologia
19.
Mol Pharm ; 17(6): 2196-2207, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32392076

RESUMO

In solid dosage formulations, probing intermolecular interactions between active pharmaceutical ingredients (APIs) and polymeric excipients, which have a mechanistic impact on physical stability as well as bioavailability, remains a challenge. In recent years, solid-state NMR spectroscopy has been demonstrated to be a powerful tool to provide structural details with an atomic resolution of therapeutic organic compounds and formulation products. However, conventional 13C-detected techniques often suffer from poor resolution and low sensitivity due to the disordered structure of certain materials such as amorphous pharmaceuticals and 13C natural abundance, hindering in-depth investigations. In this study, we utilize the magic angle spinning (MAS) technique with ultrafast speeds (UF-MAS: νR = 60 and 110 kHz) and demonstrate the enabled methods with 1H detection to study the amorphous molecular complex of rafoxanide and povidone in the solid state. The downfield shift of the RAF amide proton, resolved under UF-MAS, and its correlations with aliphatic protons of PVP, serve as strong evidence of the existence of intermolecular hydrogen bonding. Two-dimensional (2D) 1H-detected 1H{13C} and 1H-1H correlation experiments, interestingly, exhibit distinct API-polymer interactions in the spray-dried amorphous solid dispersions (ASDs), utilizing aqueous and organic cosolvents and organic solvents mixtures. The rich intermolecular interactions in the aqueously prepared ASDs presumably contribute to the physical stability, and the interactions are retained in the solution state to maintain supersaturation for an enhanced dissolution profile. This study presents the first application of UF-MAS NMR characterization of therapeutic solid dosages at a spinning frequency of 110 kHz and uncovers the molecular mechanisms of solvent-mediated pharmaceutical dispersions.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Povidona/química , Rafoxanida/química , Polímeros/química
20.
Thorac Cancer ; 11(7): 1773-1783, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32374079

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs), which have little or no ability to encode proteins, have attracted special attention due to their potential role in cancer disease. In this study we aimed to establish a lncRNAs classifier to improve the accuracy of recurrence prediction for thymic epithelial tumors (TETs). METHODS: TETs RNA sequencing (RNA-seq) data set and the matched clinicopathologic information were downloaded from the Cancer Genome Atlas. Using univariate Cox regression and least absolute shrinkage and selection operator (LASSO) analysis, we developed a lncRNAs classifier related to recurrence. Functional analysis was conducted to investigate the potential biological processes of the lncRNAs target genes. The independent prognostic factors were identified by Cox regression model. Additionally, predictive ability and clinical application of the lncRNAs classifier were assessed, and compared with the Masaoka staging by receiver operating characteristic (ROC) analysis and decision curve analysis (DCA). RESULTS: Four recurrence-free survival (RFS)-related lncRNAs were identified, and the classifier consisting of the identified four lncRNAs was able to effectively divide the patients into high and low risk subgroups, with an area under curve (AUC) of 0.796 (three-year RFS) and 0.788 (five-year RFS), respectively. Multivariate analysis indicated that the lncRNAs classifier was an independent recurrence risk factor. The AUC of the lncRNAs classifier in predicting RFS was significantly higher than the Masaoka staging system. Decision curve analysis further demonstrated that the lncRNAs classifier had a larger net benefit than the Masaoka staging system. CONCLUSIONS: A lncRNAs classifier for patients with TETs was an independent risk factor for RFS despite other clinicopathologic variables. It generated more accurate estimations of the recurrence probability when compared to the Masaoka staging system, but additional data is required before it can be used in clinical practice.


Assuntos
Recidiva Local de Neoplasia/diagnóstico , Neoplasias Epiteliais e Glandulares/cirurgia , Nomogramas , RNA Longo não Codificante/genética , Neoplasias do Timo/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , China/epidemiologia , Feminino , Seguimentos , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/genética , Neoplasias Epiteliais e Glandulares/patologia , Prognóstico , Neoplasias do Timo/patologia , Adulto Jovem
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