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51.
52.

Purpose

Artificial neural networks (ANNs) are used to optimize a formulation of poly(lactic acid) (PLA) nanoparticles containing hydrophobic drug molecules through a study of the critical parameters affecting nanoparticle size.

Methods

We evaluate the effect of input variables, including concentrations of PLA and Tween 80, amplitude of ultrasound wave, and sonication time on the formation of PLA nanoparticles, which were prepared using a solvent evaporation method. Budesonide was used as a model hydrophobic drug. An ANN model was created using training data and evaluated for prediction capability using validation data.

Results

The ANN model demonstrated that reducing PLA concentration and increasing Tween 80 concentration provided optimum conditions for the preparation of small particle size. Additionally, the simultaneous use of high sonication time and amplitude has an adverse effect on particle diameter.

Conclusion

By defining the effects of each parameter on the size of PLA nanoparticles, this study demonstrated the feasibility of using an ANN model to optimize the conditions for achieving minimum particle size in hydrophobic drug-loaded PLA nanoparticles.  相似文献   
53.
BackgroundAcetylcholine deficiencies in hippocampus and cortex, aggregation of β-amyloid, and β-secretase over activity have been introduced as main reasons in pathogenesis of Alzheimer’s disease.MethodsColorimetric Ellman’s method was used for determination of IC50 value in AChE and BChE inhibitory activity. The kinetic studies, neuroprotective and β-secretase inhibitory activities, evaluation of inhibitory potency on β-amyloid (Aβ) aggregations induced by AChE, and docking study were performed for prediction of the mechanism of action.Result and discussionA new series of cinnamic acids-tryptamine hybrid was designed, synthesized, and evaluated as dual cholinesterase inhibitors. These compounds demonstrated in-vitro inhibitory activities against acetyl cholinesterase (AChE) and butyryl cholinesterase (BChE). Among of these synthesized compounds, (E)-N-(2-(1H-indol-3-yl)ethyl)-3-(3,4-dimethoxyphenyl)acrylamide (5q) demonstrated the most potent AChE inhibitory activity (IC50 = 11.51 μM) and (E)-N-(2-(1H-indol-3-yl)ethyl)-3-(2-chlorophenyl)acrylamide (5b) were the best anti-BChE (IC50 = 1.95 μM) compounds. In addition, the molecular modeling and kinetic studies depicted 5q and 5b were mixed type inhibitor and bound with both the peripheral anionic site (PAS) and catalytic sites (CAS) of AChE and BChE. Moreover, compound 5q showed mild neuroprotective in PC12 cell line and weak β-secretase inhibitory activities. This compound also inhibited aggregation of β-amyloid (Aβ) in self-induced peptide aggregation test at concentration of 10 μM.ConclusionIt is worth noting that both the kinetic study and the molecular modeling of 5q and 5b depicted that these compounds simultaneously interacted with both the catalytic active site and the peripheral anionic site of AChE and BChE. These findings match with those resulted data from the enzyme inhibition assay. Graphical abstractOpen in a separate windowA new series of cinnamic-derived acids-tryptamine hybrid derivatives were designed, synthesized and evaluated as butyrylcholinesterase (BChE) and acetylcholinesterase (AChE) inhibitors and neuroprotective agents. Compound 5b and 5q, as the more potent compounds, interacted with both the peripheral site and the choline binding site having mixed type inhibition. Results suggested that derivatives have a therapeutic potential for the treatment of AD.Electronic supplementary materialThe online version of this article (10.1007/s40199-020-00346-9) contains supplementary material, which is available to authorized users.  相似文献   
54.
Purpose: Spray-freeze drying (SFD) is a recently applied method to develop pharmaceutical powders. This study aimed to analyze the competence of Trehalose, Mannitol, Lactose, and Sorbitol instability and aerosolization of Immunoglobulin G (IgG) via SFD.

Methods: Induced soluble aggregates were quantified at 0 and 3?months, and 45?°C using size-exclusion chromatography. Conformation and thermogravimetric assessments were done by Fourier transform infrared spectroscopy and differential scanning calorimetry. Laser light scattering was performed to determine the particle sizes. Aerodynamic features were characterized by twin stage impinger and scanning electron microscopy.

Results: Although sugars/polyols preferably stabilized IgG following the process, storage stabilization was achieved in Trehalose, Trehalose-Lactose, Lactose, and Trehalose-Mannitol-based powders with soluble aggregates <5%. The conformation of antibody was preserved with β sheet content from 66.28% to 76.37%. Particle sizes ranged from 5.23 to 8.12?µm. Mannitol exhibited the best aerodynamic behavior, fine particle fraction (FPF: 70%) but high degree of protein aggregation during storage.

Conclusions: SFD could favorably stabilize antibody using Trehalose and its combination with Lactose and Mannitol, and also, Lactose alone. Sorbitol disturbed IgG powder recovery. Incorporation of other types of excipient is required for efficient respiratory delivery of IgG molecules.  相似文献   

55.
Eurycomanone, an active constituent isolated from Eurycoma longifolia Jack, was examined for modulatory effects on cytochrome P450 (CYP) isoforms CYP1A2, CYP2A6, CYP2C8, CYP2C9, CYP2C19, CYP2E1 and CYP3A4 using in vitro assays. The IC50 value was determined to assess the potencies of modulation for each CYP isoform. Our results indicated that eurycomanone did not potently inhibit any of the CYP isoforms investigated, with IC50 values greater than 250 μg/ml. Hence there appears to be little likelihood of drug–herb interaction between eurycomanone or herbal products with high content of this compound and CYP drug substrates via CYP inhibition.  相似文献   
56.
57.
The aim of this study was preparation, optimization and in vitro characterization of nanoparticles composed of 6-[O-carboxymethyl]-[N,N,N-trimethyl] (TMCMC) for oral delivery of low-molecular-weight heparin. The chitosan derivative was synthesized. Nanoparticles were prepared using the polyelectrolyte complexation method. Box–Behnken response surface experimental design methodology was used for optimization of nanoparticles. The morphology of nanoparticles was studied using transmission electron microscopy. In vitro release of enoxaparin from nanoparticles was determined under simulated intestinal fluid. The cytotoxicity of nanoparticles on a Caco-2 cell line was determined, and finally the transport of prepared nanoparticles across Caco-2 cell monolayer was defined. Optimized nanoparticles with proper physico-chemical properties were obtained. The size, zeta potential, poly-dispersity index, entrapment efficiency and loading efficiency of nanoparticles were reported as 235?±?24.3?nm, +18.6?±?2.57?mV, 0.230?±?0.03, 76.4?±?5.43% and 12.6?±?1.37%, respectively. Morphological studies revealed spherical nanoparticles with no sign of aggregation. In vitro release studies demonstrated that 93.6?±?1.17% of enoxaparin released from nanoparticles after 600?min of incubation. MTT cell cytotoxicity studies showed no cytotoxicity at 3?h post-incubation, while the study demonstrated concentration-dependent cytotoxicity after 24?h of exposure. The obtained data had shown that the nanoparticles prepared from trimethylcarboxymethyl chitosan may be considered as a good candidate for oral delivery of enoxaparin.  相似文献   
58.
This study describes synthesis of a new group of triaryl-1,2,4-oxadiazole derivatives and their anticancer activities. The target compounds were prepared from reaction of different imines and 4-substituted benzohydroxyiminoyl chlorides. All the synthesized compounds were screened for antiproliferative activities against MCF7 and K562 cell lines using MTT assay at 50-μM concentration. Four compounds that showed more than 50 % cytotoxicity were selected for determination of IC50. Out of these, 6c-1y showed remarkable inhibitory cytotoxicity activity against MCF7 and K562 cell lines with IC50 6.50 and 21.66 μM, respectively. A molecular modeling study where 6c-1y was docked in the binding site of COX-2 showed a 2.3-Å hydrogen bond forming via hydroxyl group of Ser516 residue and oxygen of central oxadiazole ring and triaryl moiety of 6c-1y oriented toward the hydrophobic pockets of COX-2. Our data indicate that these derivatives may present promising chemotherapeutic agents, possibly targeting COX-2 pathway.  相似文献   
59.
Docetaxel (DTX) is a widely used chemotherapeutic agent with very low water solubility. Conjugation of DTX to human serum albumin (HSA) is an effective way to increase its water solubility. Attachment of folic acid (FA) or biotin as targeting moieties to DTX‐HSA conjugates may lead to active targeting and specific uptake by cancer cells with overexpressed FA or biotin receptors. In this study, FA or biotin molecules were attached to DTX‐HSA conjugates by two different methods. In one method, FA or biotin molecules were attached to remaining NH2 residues of HSA in DTX‐HSA conjugate by covalent bonds. In the second method, HSA‐FA or HSA‐biotin conjugates were synthesized separately and then combined by DTX‐HSA conjugate in proper ratio to prepare nanoparticles containing DTX‐HSA plus HSA‐FA or HSA‐biotin. Cell viability of different nanoparticle was evaluated on MDA‐MB‐231 (folate receptor positive), A549 (folate receptor negative), and 4T1 (biotin receptor positive) and showed superior cytotoxicity compared with free docetaxel (Taxotere®). In vivo studies of DTX‐HSA‐FA and DTX‐HSA‐biotin conjugates in BULB/c mice, tumorized by 4T1 cell line, showed the conjugates prepared in this study were more powerful in the reduction in tumor size and increasing the survival rate when compared to free docetaxel.  相似文献   
60.
This cross-sectional study investigated the prevalence of goitre in Isfahan, a centrally-located city in Iran, 15 years after the initiation of universal salt iodization. In total, 2,523 Isfahani adults (1,275 males, 1,248 females) aged >20 years were selected by multi-stage cluster-sampling method. Goitre rate, serum thyroid-stimulating hormone (TSH), thyroxine (T4), thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb), and urinary iodine concentration (UIC) were measured and compared between the goitrous (n=478) and the non-goitrous (n=2,045) participants. The total goitre rate was 19% (n=478) of the 2,523 adults. The rate of Grade I and II goitre was 12.4% (n=312) and 6.6% (n=166) respectively. The total goitre rate, Grade I and II goitre were more prevalent among women than among men. Hypothyroidism was observed in 6.4% (130/2,045) and 18.6% (89/478) of the non-goitrous and goitrous participants respectively [odds ratio (OR)=3.6, 95% confidence interval (CI) 2.7-4.9, p=0.001]. Hyperthyroidism was present in 0.8% (17/2,045) and 5.2% (29/478) of the non-goitrous and goitrous adults respectively (OR=9.0, 95% CI 4.9-16.6, p=0.001). Hypothyroidism was more prevalent in Grade II than in Grade I goitre and among those without goitre (31.3%, 14.1%, and 6.4% respectively) (p=0.001). Positive TPOAb was observed in 24% (n=50) of the non-goitrous and 33.5% (n=84) of the goitrous subjects (p=0.03). Positive TPOAb was observed in 24.6% (35 of 142) of the Grade I and 45% (49 of 109) of the Grade II goitrous adults (p=0.001). Positive TgAb was observed in 21.6% (n=45) of the non-goitrous and 35.9% (n=90) of the goitrous adults (p=0.001). Positive TgAb was observed in 30.3% (43 of 142) of the Grade I and 43.1% (47 of 109) of the Grade II goitrous adults (p=0.04). The median UIC was 18 μg/dL (range 1-80 μg/dL). It was 17.9 μg/dL and 19 μg/dL in the non-goitrous and goitrous adults respectively. After 15 years of successful universal salt iodization in Isfahan, goitre is still endemic, which may be due to thyroid autoimmunity. However, other environmental or genetic factors may have a role.Key words: Autoimmunity, Cross-sectional studies, Goitre, Hypothyroidism, Hyperthyroidism, Impact studies, Iodine, Iodine deficiency, Iran  相似文献   
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