Diabetic Retinopathy Analysis—Effects of Nanoparticle-Based Triamcinolone

2020 ◽  
Vol 20 (10) ◽  
pp. 6111-6115
Author(s):  
Shufang Du ◽  
Hongwei Wang ◽  
Feng Jiang ◽  
Ying Wang

Triamcinolone (TA) is a hormone corticosteroid drug used to treat edema, inflammation, and angiogenic eye diseases. It can be administered by intravitreal injection at an early stage. The intraocular instillation method can improve the bioavailability of TA by loading the drug on to a nanostructured lipid carrier (NLC). The nanoparticles (20 to 200 nm) used in this experiment were previously prepared by high-pressure homogenization using a factorial optimization design method. The NLC produced contained a distinct peak with a negative charge. The nanoparticles were loaded with drugs (TA-NLC) and fluorescent Nile Red lipids. Using the treated nanoparticles, NR-NLC was dripped into the eyes of mice in an in vivo test, demonstrating the ability to deliver lipophilic active substances to the posterior ocular segment. The short- and long-term stability of TA-NLC was also evaluated using a Turbiscan® high-performance stability analysis. Results showed that backscattering in the 6-month stability test was less than 1.5%. When stored at room temperature, the possibility of the nanoparticles condensing into flocs during the storage period is very small.

2021 ◽  
Author(s):  
Yipu Wang ◽  
Dong Mei ◽  
Xinyi Zhang ◽  
Da-Hui Qu ◽  
Ju Mei ◽  
...  

With increase of social aging, Alzheimer's disease (AD) has been one of the serious diseases threatening human health. The occurrence of A<i>β </i>fibrils<i> </i>or plaques is recognized as the hallmark of AD.<i> </i>Currently, optical imaging has stood out to be a promising technique for the imaging of A<i>β</i> fibrils/plaques and the diagnosis of AD. However, restricted by their poor blood-brain barrier (BBB) penetrability, short-wavelength excitation and emission, and aggregation-caused quenching (ACQ) effect, the clinically used gold-standard optical probes such as <a>thioflavin</a> T (ThT) and thioflavin S (ThS), are not effective enough in the early diagnosis of AD <i>in vivo</i>. Herein, we put forward an “all-in-one” design principle and demonstrate its feasibility in developing high-performance fluorescent probes which are specific to A<i>β</i> fibrils/plaques and promising for super-early <i>in</i>-<i>vivo</i> diagnosis of AD. As a proof of concept, a simple rod-like amphiphilic NIR fluorescent AIEgen, i.e., AIE-CNPy-AD, is developed by taking the specificity, BBB penetration ability, deep-tissue penetration capacity, high signal-to-noise ratio (SNR) into consideration. AIE-CNPy-AD is constituted by connecting the electron-donating and accepting moieties through single bonds and tagging with a propanesulfonate tail, giving rise to the NIR fluorescence, aggregation-induced emission (AIE) effect, amphiphilicity, and rod-like structure, which in turn result in high binding-affinity and excellent specificity to A<i>β</i> fibrils/plaques, satisfactory ability to penetrate BBB and deep tissues, ultrahigh SNR and sensitivity, and high-fidelity imaging capability. <i>In-vitro, ex-vivo,</i> and <i>in-vivo</i> <a>identifying of A<i>β</i> fibrils/plaques</a> in different strains of mice indicate that AIE-CNPy-AD holds the universality to the detection of A<i>β</i> fibrils/plaques. It is noteworthy that AIE-CNPy-AD is even able to trace the small and sparsely distributed A<i>β</i> fibrils/plaques in very young AD model mice such as 4-month-old APP/PS1 mice which are reported to be the youngest mice to have A<i>β</i> deposits in brains, suggesting its great potential in diagnosis and intervention of AD at a super-early stage.


Author(s):  
RAJA NAVAMANISUBRAMANIAN ◽  
SABITHA PANCHAGIRI ◽  
RAGHUNANDAN NERELLA ◽  
CHAMUNDEESWARI DURAIPANDIAN ◽  
SHANMUGANATHAN SEETHARAMAN

Objective: A simple, selective and sensitive reverse-phase high-performance liquid chromatography (RP-HPLC) method to estimate repaglinide (REP) in rabbit plasma using rabeprazole (RAB) as an internal standard was developed and validated for various qualifications. Methods: The chromatographic separation was performed on C18 (2) analytical column (5 μ, 250×4.6 mm) using acetonitrile: 0.05% trifluoroacetic acid in water (55:45, v/v) as mobile phase at the flow rate of 1 ml/min. Validation of the analytical method was performed as per ICH guidelines. Results: The retention times of REP and RAB were found at ~4.3 and 5.1 min respectively, with adequate system suitability parameters (theoretical plates ≥3619, tailing factor ≤1.38, resolution factor 2.37). The method has linearity over a concentration range of 10 to 1000 ng/ml (r2=0.9987). The results of accuracy (≥98.17%), intra-, inter-day precision (≤2.9%), recovery (101.21±2.09%) and process efficiency (99.77±3.74%) found satisfactory with no matrix effect. The analyte in samples were found stable up to 6 h, 3 freeze-thaw cycles and not more than 2 mo corresponding to bench-top, short and long term stability studies respectively. Conclusion: The developed RP-HPLC method for estimation of REP in rabbit plasma was developed. The method was found to be rapid, cost-effective and accurate to estimate the REP from the sample matrix. The method can be a most useful tool for in vivo study of REP in the rabbit.


2020 ◽  
Vol 8 (A) ◽  
pp. 338-341
Author(s):  
Samran Samran ◽  
Hari Ronaldo Tanjung

BACKGROUND: Bioavailability and bioequivalence studies required by regulations to ensure therapeutic equivalence between a pharmaceutically equivalent test product and a reference product. AIM: This study aimed to evaluate the bioavailability performance between the optimum formula of OROS dispersible tablet-metoclopramide dosage forms (FCL-6) and the Primperan® as the reference product. METHODS: The FCL-6 formula was design by simplex lattice design model with a three components mixture of excipients: Solid tapai extract, corn starch, and Avicel. The optimum formula of OROS dispersible tablet (ODT)-metoclopramide consists of solid tapai extract (27.038 mg), corn starch (27.407 mg), and Avicel (53.555 mg), metoclopramide hydrochloric acid (HCl) (10.00 mg), LH-11 (22.50 mg), aspartame (5.00 mg), talcum BP (3.00 mg), and Mg stearate (1.50 mg). The in vivo test was done by cross-over design method using six rabbits. The level of metoclopramide concentration from in vivo test was measured by high-performance liquid chromatography instrument. RESULTS: The study revealed that the tmax, Cmax, and area under curve (AUC) of ODT-metoclopramide FCL-6 were 60 min, 1.95 ± 0.13 μg/mL, and 1118.20 ± 150 μg/mL. min consecutively. The Cmax and the concentration of the drug absorbed in the blood (AUC) of ODT-metoclopramide were larger than Primperan® tablets. Statistical data of the optimized ODT-metoclopramide compared with Primperan® showed that the Cmax and AUC significance values were <0.05 (p < 0.05). CONCLUSION: The optimized formula of ODT-metoclopramide revealed a better characteristic of Cmax and AUC concentration compared with Primperan®. The optimized ODT-metoclopramide with tapai extract was found to be promising to improved bioavailability of metoclopramide.


2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Neng Zhou ◽  
Dangmei Liu ◽  
Xiaowang Bao

Simple and rapid high-performance liquid chromatography methods were developed for the determination of berberine (BB) in various rat tissues so as to evaluate a P-gp inhibitor, glycyrrhetinic acid (GA), on BB’s oral bioavailability. Acetonitrile was used to extract BB from tissues and showed different extraction recoveries in diverse tissues. The intra- and interday precision and accuracy were less than 10%. Long-term stability, pre (post) -preparative stability, and freeze-thaw stability were evaluated, and the results showed it could meet the need of this study. The proposed methods were subsequently applied to investigate the possible drug-drug interaction of GA and BB in vivo from the aspect of tissue distribution. The results showed that no significant difference was found between the group of low dose and high dose at the same time point. The tissue distributions show a saturated model, i.e., the content of BB in tissue tends to be constant while its dose is more than 200 mg/kg. Besides, the contents of BB ranged from high to low according to the order of the liver, kidney, and spleen. The BB content in the liver is especially high as compared to other tissues.


2019 ◽  
Vol 55 (3) ◽  
pp. 188-192
Author(s):  
M. L. Colsoul ◽  
A. Breuer ◽  
N. Goderniaux ◽  
J. D. Hecq ◽  
L. Soumoy ◽  
...  

Background and Objective: Infusion containing lorazepam is used by geriatric department to limit anxiety disorders in the elderly. Currently, these infusions are prepared according to demand by the nursing staff, but the preparation in advance in a centralized service could improve quality of preparation and time management. The aim of this study was to investigate the long-term stability of this infusion in polypropylene syringes stored at 5 ± 3°C. Then, results obtained were compared with stability data of lorazepam in syringes stored at room temperature, glass bottles at 5 ± 3°C, and glass bottles at room temperature. Method: Eight syringes and 6 bottles of infusion were prepared by diluting 1 mL lorazepam 4 mg in 23 mL of NaCl 0.9% under aseptic conditions. Five syringes and 3 bottles were stored at 5 ± 3°C and 3 syringes and 3 bottles were stored at room temperature for 30 days. During the storage period, particle appearance or color change were periodically checked by visual and microscope inspection. Turbidity was assessed by measurements of optical density (OD) at 3 wavelengths (350 nm, 410 nm, 550 nm). The stability of pH was also evaluated. The lorazepam concentrations were measured at each time point by high-performance liquid chromatography with ultraviolet detector at 220 nm. Results: Solutions were physically unstable in syringes at 5 ± 3°C after 4 days: crystals and a drop of OD at 350 nm were observed. However, pH was stable. After 2 days, solutions were considered as chemically unstable because a loss of lorazepam concentration higher than 10% was noticed: the lower 1-sided confidence limit at 95% was below 90% of the initial concentration. To assess temperature and polypropylene influence, results were compared with those obtained for syringes at room temperature and bottles at 5 ± 3°C and room temperature. Precipitation, drop of OD at 350 nm, and chemical instability were observed in all conditions. Conclusion: Solutions of lorazepam were unstable after 2 days in syringes at 5 ± 3°C. Preparation in advance appears, therefore, not possible for the clinical use. Storage conditions (temperature and form) do not improve the stability.


Author(s):  
Mushfiq Akanda ◽  
Giulia Getti ◽  
Dennis Douroumis

AbstractNanostructure lipid carriers (NLCs) were developed for the delivery of curmumin (CRN), a potent anticancer agent with low bioavailability, for the treatment of prostate cancer. NLCs prepared using high pressure homogenization (HPH) with around 150 nm particle size, − 40 V ζ-potential and excellent long-term stability. Cellular uptake of CRN-SLN showed nanoparticle localization in the cytoplasm around the nucleus. CRN-NLCs were assessed using flow cytometry and found to cause early and late apoptotic events at 100 μg/ml CRN concentrations. CRN-NLC nanoparticles were administrated to nude mice with LNCaP prostate cancer xenografts and demonstrated substantial tumour volume suppression (40%) with no weight loss compared to pure CRN (ethanolic solution). Overall, NLCs were proved a suitable carrier for passive drug delivery and cancer treatment. Graphical abstract


2021 ◽  
Author(s):  
Mushfiq Akanda ◽  
Giulia Getti ◽  
Dennis Douroumis

Abstract Nanostructure lipid carriers (NLCs) were developed for the delivery of curmumin (CRN), a potent anticancer agent with low bioavailability, for the treatment of prostate cancer. NLCs prepared using High Pressure Homogenization (HPH) with around 150 nm particle size, -40V ζ-potential and excellent long-term stability. Cellular uptake of CRN-SLN, showed nanoparticle localization in the cytoplasm around the nucleus. CRN-NLCs were assessed using flow cytometry and found to cause early and late apoptotic events at 100 μg/ml CRN concentrations. CRN-NLC nanoparticles were administrated to nude mice with LNCaP prostate cancer xenografts and demonstrated substantial tumour volume suppression (40%) with no weight loss compared to pure CRN (ethanolic solution). Overall, NLCs were proved a suitable carrier for passive drug delivery and cancer treatment.


2020 ◽  
Vol 40 (8) ◽  
pp. 0831001
Author(s):  
谢钟涛 Xie Zhongtao ◽  
余桂英 Yu Guiying

2021 ◽  
Author(s):  
Yipu Wang ◽  
Dong Mei ◽  
Xinyi Zhang ◽  
Da-Hui Qu ◽  
Ju Mei ◽  
...  

With increase of social aging, Alzheimer's disease (AD) has been one of the serious diseases threatening human health. The occurrence of A<i>β </i>fibrils<i> </i>or plaques is recognized as the hallmark of AD.<i> </i>Currently, optical imaging has stood out to be a promising technique for the imaging of A<i>β</i> fibrils/plaques and the diagnosis of AD. However, restricted by their poor blood-brain barrier (BBB) penetrability, short-wavelength excitation and emission, and aggregation-caused quenching (ACQ) effect, the clinically used gold-standard optical probes such as <a>thioflavin</a> T (ThT) and thioflavin S (ThS), are not effective enough in the early diagnosis of AD <i>in vivo</i>. Herein, we put forward an “all-in-one” design principle and demonstrate its feasibility in developing high-performance fluorescent probes which are specific to A<i>β</i> fibrils/plaques and promising for super-early <i>in</i>-<i>vivo</i> diagnosis of AD. As a proof of concept, a simple rod-like amphiphilic NIR fluorescent AIEgen, i.e., AIE-CNPy-AD, is developed by taking the specificity, BBB penetration ability, deep-tissue penetration capacity, high signal-to-noise ratio (SNR) into consideration. AIE-CNPy-AD is constituted by connecting the electron-donating and accepting moieties through single bonds and tagging with a propanesulfonate tail, giving rise to the NIR fluorescence, aggregation-induced emission (AIE) effect, amphiphilicity, and rod-like structure, which in turn result in high binding-affinity and excellent specificity to A<i>β</i> fibrils/plaques, satisfactory ability to penetrate BBB and deep tissues, ultrahigh SNR and sensitivity, and high-fidelity imaging capability. <i>In-vitro, ex-vivo,</i> and <i>in-vivo</i> <a>identifying of A<i>β</i> fibrils/plaques</a> in different strains of mice indicate that AIE-CNPy-AD holds the universality to the detection of A<i>β</i> fibrils/plaques. It is noteworthy that AIE-CNPy-AD is even able to trace the small and sparsely distributed A<i>β</i> fibrils/plaques in very young AD model mice such as 4-month-old APP/PS1 mice which are reported to be the youngest mice to have A<i>β</i> deposits in brains, suggesting its great potential in diagnosis and intervention of AD at a super-early stage.


2021 ◽  
Vol 11 (15) ◽  
pp. 6671
Author(s):  
Yisheng Chen ◽  
Qianglong Wang ◽  
Chong Wang ◽  
Peng Gong ◽  
Yincheng Shi ◽  
...  

In the aerospace industry, spacecraft often serve in harsh operating environments, so the design of ultra-lightweight and high-performance structures is a major requirement in aerospace structure design. In this article, a lightweight aerospace bracket considering fatigue performance was designed by topology optimization and manufactured by 3D-printing. Considering the requirements of assembly with a fixture for fatigue testing and avoiding stress concentration, a reconstructed model was presented by CAD software before manufacturing. To improve the fatigue performance of the structure, this article proposes the design idea of abstracting the practiced working condition of the bracket subjected to cycle loads in the vertical direction via a multiple load-case topology optimization problem by minimizing compliance under a variety of asymmetric extreme loading conditions. Parameter sweeping was used to improve the computational efficiency. The mass of the new bracket was reduced by 37% compared to the original structure. Both numerical simulation and the fatigue test were implemented to support the validity of the new bracket. This work indicates that the integration of the proposed topology optimization design method and additive manufacturing can be a powerful tool for the design of lightweight structures considering fatigue performance.


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