A novel diblock copolymer of (monomethoxy poly [ethylene glycol]-oleate) with a small hydrophobic fraction to make stable micelles/polymersomes for curcumin delivery to cancer cells

Curcumin is a potent natural anticancer agent, but its effectiveness is limited by properties such as very low solubility, high rate of degradation, and low rate of absorption of its hydrophobic molecules in vivo. To date, various nanocarriers have been used to improve the bioavailability of this hydrophobic biomaterial. This study investigates the encapsulation of curcumin in a novel nanostructure of monomethoxy poly(ethylene glycol)-oleate (mPEG-OA) and its anticancer effect. Tests were done to determine the critical micelle concentration (CMC), encapsulation efficiency, drug-loading efficiency, and cytotoxicity (against U87MG brain carcinoma cells and HFSF-PI3 cells as normal human fibroblasts) of some nanodevice preparations. The results of fluorescence microscopy and cell-cycle analyses indicated that the in vitro bioavailability of the encapsulated curcumin was significantly greater than that of free curcumin. Cytotoxicity evaluations showed that half maximal inhibitory concentrations of free curcumin and curcumin-loaded mPEG-OA for the U87MG cancer cell line were 48 μM and 24 μM, respectively. The Annexin-V-FLUOS assay was used to quantify the apoptotic effect of the prepared nanostructures. Apoptosis induction was observed in a dose-dependent manner after curcumin-loaded mPEG-OA treatments. Two common self-assembling structures, micelles and polymersomes, were observed by atomic force microscopy and dynamic light scat­tering, and the abundance of each structure was dependent on the concentration of the diblock copolymer. The mPEG-OA micelles had a very low CMC (13.24 μM or 0.03 g/L). Moreover, atomic force microscopy and dynamic light scattering showed that the curcumin-loaded mPEG-OA polymersomes had very stable structures, and at concentrations 1,000 times less than the CMC, at which the micelles disappear, polymersomes were the dominant structures in the dispersion with a reduced size distribution below 150 nm. Overall, the results from these tests revealed that this nanocarrier can be considered as an appropriate drug delivery system for delivering curcumin to cancer cells. © 2014 Erfani-Moghadam et al

Use of single-chain antibody derivatives for targeted drug delivery

Single-chain antibodies (scFvs), which contain only the variable domains of full-length antibodies, are relatively small molecules that can be used for selective drug delivery. In this review, we discuss how scFvs help improve the specificity and efficiency of drugs. Small interfering RNA (siRNA) delivery using scFv-drug fusion peptides, siRNA delivery using scFv-conjugated nanoparticles, targeted delivery using scFv-viral peptide-fusion proteins, use of scFv in fusion with cell-penetrating peptides for effective targeted drug delivery, scFv-mediated targeted delivery of inorganic nanoparticles, scFv-mediated increase of tumor killing activity of granulocytes, use of scFv for tumor imaging, site-directed conjugation of scFv molecules to drug carrier systems, use of scFv to relieve pain and use of scFv for increasing drug loading efficiency are among the topics that are discussed here. © 2016, University of Michigan. All rights reserved

Frequency of ochratoxin A in bread consumed in Shahrekord

زمینه و هدف: با اکراتوکسین A مایکوتوکسینی است که به علت اثرات نفروتوکسیک، ایمونوتوکسیک، موتاژنیک، تراتوژنیک و کار سینوژنیک خطر بالقوه ی برای سلامت انسان دارد. این مطالعه با هدف تعیین حضور و میزان اکراتوکسین A در نان های مصرفی شهرکرد انجام شده است. روش بررسی: در این مطالعه مقطعی تحلیلی، 86 نمونه انواع نان عرضه شده در نانوایی های شهرستان شهرکرد از پاییز 1389 تا بهار 1390 جمع آوری و از نظر حضور اکراتوکسین A به وسیله روش الایزا مورد بررسی قرار گرفت. داده ها به کمک آزمون های آماری تحلیل واریانس یک طرفه و آزمون t تجزیه و تحلیل شد. یافته ها: اکراتوکسین A در 45 نمونه از 86 نمونه (3/52 درصد) نان بررسی شده ردیابی شد. محدوده غلظت اکراتوکسین A در نمونه های مثبت بین 19/0 تا 37/10 نانو گرم بود و میانگین آلودگی نمونه های آلوده 47/1±61/2 نانو گرم در گرم به دست آمد. سطح آلودگی 15 نمونه (4/17درصد) از مجموع 86 نمونه آزمایش شده بیش از حداکثر مجاز (5 نانو گرم در گرم) تأیید شده در قوانین اتحادیه اروپا بود. اختلاف آماری معنی داری بین سطوح آلودگی و تعداد موارد آلوده در فصول مختلف وجود نداشت (p>0.05). نتیجه گیری: نتایج این مطالعه نشان می دهد که بررسی منظم سطح اکراتوکسین A در غلات به خصوص گندم از اهمیت ویژه ای برخوردار است؛ زیرا بر این اساس می توان روش های مناسبی جهت کاهش آلودگی به اکراتوکسین A و بهبود کیفیت نان ارائه نمود

Influence of shock wave propagation on dielectric barrier discharge plasma actuator performance

Interest in plasma actuators as active flow control devices is growing rapidly due to their lack of mechanical parts, light weight and high response frequency. Although the flow induced by these actuators has received much attention, the effect that the external flow has on the performance of the actuator itself must also be considered, especially the influence of unsteady high-speed flows which are fast becoming a norm in the operating flight envelopes. The primary objective of this study is to examine the characteristics of a dielectric barrier discharge (DBD) plasma actuator when exposed to an unsteady flow generated by a shock tube. This type of flow, which is often used in different studies, contains a range of flow regimes from sudden pressure and density changes to relatively uniform high-speed flow regions. A small circular shock tube is employed along with the schlieren photography technique to visualize the flow. The voltage and current traces of the plasma actuator are monitored throughout, and using the well-established shock tube theory the change in the actuator characteristics are related to the physical processes which occur inside the shock tube. The results show that not only is the shear layer outside of the shock tube affected by the plasma but the passage of the shock front and high-speed flow behind it also greatly influences the properties of the plasma

Histomorphometrical study of silver carp fish testis in two age classes

In this research, morphological and histomorphometrical structure of testis of 20 silver male carp fish were studied in two classes or groups. Group1 was composed of 10 fish with average (±SD) weight of 1.247+0.656kg and average(±SD) length of 43.675+1.414cm with about 2 years age, Group2 was composed of 10 fish with average(±SD) weight of 5.716+0.519kg and average(±SD) length of 81.5+1.643cm. Average (±SD) weight of testis were 2.34+1.47gr and 83.33+25.81gr with average (±SD) GSI of 0.187+0.224 and 1.457+4.974 in groups 1 and 2 respectively. Samples from testis were taken by maximum thickness of 0.5cm and after fixation in bouin , s fixative and 5-6µm thickness section were made routine paraffin embedding method and stained by Hematoxylin-Eosin and PAS staining. The microscopic results showed that the silver carp testis was lobular and cystic type in two groups. In group 1, there was no spermatozoon activity and PGCs were only germ cells in the cysts. But in group2, the numbers of PGCs were decreased significantly and spermatogenic cells were seen in different phases including spermatogonia, primary and secondary spermatocysts, early and late spermatid, and spermatozoa which each one was located in a separated cyst. There was no significant difference in nucleus diameter of PGCs in testis of group1 (6.97+0.438µ) and group (6.13+0.438µ). In group2, the nucleolus diameter of spermatogonia was 2.97+0.112µm, primary spermatocyt 3.59+0.107µ, early spermatid 1.59+0.761µ, late spermatid 1.24+0.132µ, spermatozoa 1.16+0.054µ, and the length of spermatozoia 17.412+1.946µ. The interesting finding was immature testis in fish of group 1 with average weigh (1.247+0.656kg) and average length (43.675+1.414cm) in about 2 years age and mature testis in fish of group 2 with average weight of (5.716+0.519kg) and average length of (81.5+1.643cm) with about 4 years age in Khuzestan climate conditions

Adversarial Coreset Selection for Efficient Robust Training

Neural networks are vulnerable to adversarial attacks: adding well-crafted, imperceptible perturbations to their input can modify their output. Adversarial training is one of the most effective approaches to training robust models against such attacks. Unfortunately, this method is much slower than vanilla training of neural networks since it needs to construct adversarial examples for the entire training data at every iteration. By leveraging the theory of coreset selection, we show how selecting a small subset of training data provides a principled approach to reducing the time complexity of robust training. To this end, we first provide convergence guarantees for adversarial coreset selection. In particular, we show that the convergence bound is directly related to how well our coresets can approximate the gradient computed over the entire training data. Motivated by our theoretical analysis, we propose using this gradient approximation error as our adversarial coreset selection objective to reduce the training set size effectively. Once built, we run adversarial training over this subset of the training data. Unlike existing methods, our approach can be adapted to a wide variety of training objectives, including TRADES, $\ell_p$-PGD, and Perceptual Adversarial Training. We conduct extensive experiments to demonstrate that our approach speeds up adversarial training by 2-3 times while experiencing a slight degradation in the clean and robust accuracy.Comment: Accepted to the International Journal of Computer Vision (IJCV). Extended version of the ECCV2022 paper: arXiv:2112.00378. arXiv admin note: substantial text overlap with arXiv:2112.0037

The Devil's Advocate: Shattering the Illusion of Unexploitable Data using Diffusion Models

Protecting personal data against exploitation of machine learning models is crucial. Recently, availability attacks have shown great promise to provide an extra layer of protection against the unauthorized use of data to train neural networks. These methods aim to add imperceptible noise to clean data so that the neural networks cannot extract meaningful patterns from the protected data, claiming that they can make personal data "unexploitable." This paper provides a strong countermeasure against such approaches, showing that unexploitable data might only be an illusion. In particular, we leverage the power of diffusion models and show that a carefully designed denoising process can counteract the effectiveness of the data-protecting perturbations. We rigorously analyze our algorithm, and theoretically prove that the amount of required denoising is directly related to the magnitude of the data-protecting perturbations. Our approach, called AVATAR, delivers state-of-the-art performance against a suite of recent availability attacks in various scenarios, outperforming adversarial training even under distribution mismatch between the diffusion model and the protected data. Our findings call for more research into making personal data unexploitable, showing that this goal is far from over. Our implementation is available at this repository: https://github.com/hmdolatabadi/AVATAR.Comment: Accepted to the 2024 IEEE Conference on Secure and Trustworthy Machine Learning (SatML

Effect of Carbohydrate Source and Addition Canola Seed on Growth Performance and Nutrient Digestibility of Lambs

The objective of this study was to investigate effects of partial replacement of starch with neutral detergent soluble fiber with or without roasted canola seed as a fat source, and possible interactions on apparent digestibility and growth performance of growing lambs. For this purpose, 24 male lambs were used in a completely randomized design with a 2×2 factorial arrangement of treatments. Dietary treatments were 1- starch from barley, 2- starch from barley with roasted canola seed, 3- soluble fiber from beet pulp, and 4- soluble fiber from beet pulp with roasted canola seed. The experimental period was 84 days and forage:concentrate ratio was 10:90 for all diets. Treatments had no significant effect on the dry matter intake, feed conversion ratio, apparent digestibility of protein and organic matter (p>0.05). High starch diets compared with high soluble fiber diets caused a significant decrease in the digestibility of dry matter, organic matter, ADF and NDF (p<0.01). Canola seed addition to the diets significantly decreased ADF and NDF digestibility (p<0.01). The carbohydrate source by canola seed interaction was significant for weight gain and rumen pH (p<0.01) indicating that addition of canola seed to high starch diet increased weight gain and rumen pH more dramatically in comparison with soluble fiber diet (p<0.01). It is concluded that addition of canola seed to high starch diet had favorable effects on growth performance and rumen pH but because of its negative effect on fiber digestibility and its different response depend on carbohydrate source, more research is needed for conclusion