Explore the vast range of titles available.

This study aimed to control rapid localized corrosion and inflammation of biodegradable magnesium implants by developing a pH-responsive mPEG-PLGA coating loaded with dexamethasone (Dex). The mPEG-PLGA layer was designed to selectively degrade in alkaline conditions, thereby moderating pH elevation at the implant surface while enabling controlled Dex release. By varying the molecular weight of mPEG and PLGA, the degradation rate and microsphere size were tunable, allowing adjustment of the drug release profile. Among the tested coating solution concentrations (1.5–7.5 mg/mL), the formulation with 3 mg/mL Dex yielded a final cumulative release concentration of 0.02 mg/mL over a two-week period, which suppressed inflammatory responses in RAW 264.7 macrophages with minimal cytotoxicity, while enhancing BMP-2 and RUNX2 expression in mesenchymal stem cells. In a rat femur defect model, Mg implants coated with mPEG-PLGA containing 3 mg/mL Dex significantly increased bone volume and bone mineral density and reduced early TNF-α expression, accompanied by continuous new bone formation and strong BSP-positive osseointegration. These findings suggest that the proposed pH-responsive mPEG-PLGA/Dex coating provides a promising strategy to simultaneously regulate corrosion, attenuate inflammation, and promote bone regeneration around magnesium implants.

H.264 Advanced Video Coding or MPEG-4 Part 10 is fundamental to a growing range of markets such as high definition broadcasting, internet video sharing, mobile video and digital surveillance. This book reflects the growing importance and implementation of H.264 video technology. Offering a detailed overview of the system, it explains the syntax, tools and features of H.264 and equips readers with practical advice on how to get the most out of the standard. Packed with clear examples and illustrations to explain H.264 technology in an accessible and practical way. Covers basic video coding concepts, video formats and visual quality. Explains how to measure and optimise the performance of H.264 and how to balance bitrate, computation and video quality. Analyses recent work on scalable and multi-view versions of H.264, case studies of H.264 codecs and new technological developments such as the popular High Profile extensions. An invaluable companion for developers, broadcasters, system integrators, academics and students who want to master this burgeoning state-of-the-art technology. \"[This book] unravels the mysteries behind the latest H.264 standard and delves deeper into each of the operations in the codec. The reader can implement (simulate, design, evaluate, optimize) the codec with all profiles and levels. The book ends with extensions and directions (such as SVC and MVC) for further research.\"  Professor K. R. Rao, The University of Texas at Arlington, co-inventor of the Discrete Cosine Transform

In this study, we developed a chlorin e6-conjugated methoxy-poly(ethylene glycol)-poly(d,l-lactide) (mPEG-PLA-Ce6) amphiphilic polymer, which self-assembled to form stable nanoparticles. The nanoparticles were characterized for particle size, ζ-potential and singlet oxygen ( O ) generation. Cellular internalization and phototoxicity were investigated against monolayer and 3D spheroids of human lung adenocarcinoma cells (A549). mPEG-PLA-Ce6 exhibited a size of 149.72 ± 3.51 nm and ζ-potential of -24.82 ± 2.94 mV. The O generation by mPEG-PLA-Ce6 in water was considerably higher than free chlorin e6. The nanoparticles showed enhanced cellular internalization and phototoxicity in monolayer and 3D spheroids. The developed mPEG-PLA-Ce6 has potential application as a nanocarrier of chlorin e6 for photodynamic therapy of solid tumors.

Astragaloside (AS) has an anti-osteoporotic effect, but its poor water solubility and low bioavailability limit its application. In this study, a novel nano-carrier with bone targeting was prepared by modifying mPEG-PLGA with alendronate (AL) before incorporation into astragaloside nano-micelles (AS-AL-mPEG-PLGA) to enhance the oral bioavailability, bone targeting and anti-osteoporosis effect of AS. The release behavior of AS-AL-mPEG-PLGA in vitro was investigated via dialysis. The pharmacokinetics of AS-AL-mPEG-PLGA was studied in Sprague-Dawley (SD) rats. The cytotoxicity of AS-AL-mPEG-PLGA in vitro (via MTT method), coupled with bone targeting ability in vitro and in vivo were evaluated. The therapeutic effects of free AS and AS-AL-mPEG-PLGA (ELISA, micro-CT, H&E staining) were compared in osteoporotic rats. AS-AL-mPEG-PLGA with smaller particle size (45.3 ± 3.8 nm) and high absolute zeta potential (−23.02 ± 0.51 mV) were successfully prepared, wherein it demonstrated higher entrapment efficiency (96.16 ± 0.18%), a significant sustained-release effect for 96 h and acceptable safety within 10-200 μg/mL. AS-AL-mPEG-PLGA could enhance the hydroxyapatite affinity and bone tissue concentration of AS. The relative bioavailability of AS-AL-mPEG-PLGA was 233.90% compared with free AS. In addition, the effect of AS in reducing serum levels of bone metabolism-related indicators, restoring the bone microarchitecture and improving bone injury could be enhanced by AS-AL-mPEG-PLGA. AS-AL-mPEG-PLGA with small particle size, good stability, remarkable sustained-release effect, safety and bone targeting was successfully constructed in this experiment to potentially improve the oral bioavailability and anti-osteoporosis effect of AS. Thus, AS-AL-mPEG-PLGA may be a promising strategy to prevent and treat osteoporosis.

Tripterygium wilfordii Hook F, a traditional medicine in China has bioactive but toxic triptolide (TP, a diterpenoid triepoxide) as its main active constituents. The applications of TP are hampered by its prominent toxicity and low solubility in water. In this study, a safe pH-sensitive material [methoxy polyethylene glycol (mPEG)- adipic dihydrazide (ADH)] was synthesized and loaded with TP to form pH-sensitive polymeric micelles, thereby improving the safety and solubility of TP, as well as providing a theoretical basis for the wide application of TP. The mPEG-ADH/TP micelles were characterized by a series of indicators [namely entrapment efficiency (EE), critical micellar concentration (CMC), electrokinetic potential, stability, polydispersed index (PDI), and particle size]. Also, we ascertained the in vitro release of TP from mPEG-ADH/TP micelles along with pharmacokinetic investigations in vivo. Besides, we evaluated the cytotoxicity of mPEG-ADH/TP micelles against A549 cells, HCT116 cells, and HaCat cells and further conducted in vivo toxicity studies in rats. The TP-loaded mPEG-ADH micelles had smaller sized particles (48.3 nm), excellent PDI (0.142), stable property and higher EE (89.87%). Importantly, the TP in the mPEG-ADH/TP micelles was almost completely released at acidic pH (pH 5.0), while the drug was released slowly and sparingly at physiological pH (pH 7.4). The results suggest the release of TP from mPEG-ADH/TP micelles was sensitive to pH, which could facilitate targeting of the drug into intra-cellularly low pH endosomes and lysosomes as well as enhance cytotoxicity in cancer tissues. Moreover, mPEG-ADH/TP micelles exhibited excellent proliferation inhibition on tumor cells. In addition, the liver injury of rats in the 1 mg/kg dose of mPEG-ADH/TP micelles group was significantly reduced by Hematoxylin–eosin (HE) staining. Taken together, mPEG-ADH/TP micelles could act as a promising alternative to enhance the efficacy of oncologic treatments.

Membranous glomerulonephritis (MN) is clinically marked by significant proteinuria or nephrotic syndrome, and pathologically by a uniform thickening of the glomerular capillary basement membrane due to diffuse subepithelial immune complex deposition without notable cell proliferation. In this study, we synthesized a novel therapeutic agent, compound 1, designed for synergistic use with Eculizumab (Ecu) in MN treatment. To optimize the delivery and therapeutic effect of this combination, we developed an advanced composite drug carrier, mPEG-pHPMA@CP1@1@Ecu, incorporating methoxy polyethylene glycol (mPEG) and poly(2-hydroxypropyl methacrylamide) (pHPMA) with a metal-organic framework known as CP1. Structural and compositional integrity of this carrier was rigorously characterized. Our studies demonstrated that mPEG-pHPMA@CP1@1@Ecu could significantly mitigate hypoxia-induced renal tubular epithelial cell damage, highlighting the synergistic potential of compound 1 and Ecu. This new carrier system shows promising therapeutic potential for MN management.

In today’s digitally connected world, where cyber threats are becoming increasingly complex, finding modern and secure text encryption solutions that maintain maximum runtime performance while offering high-level protection is more crucial. The deployment of sophisticated security paradigms is often accompanied by a significant escalation in computational overhead. Thus, the fundamental objective resides in the mitigation of computational overhead while maintaining an uncompromising security posture. Internet of Things (IoT) devices require strong security measures for data transmission. Also, protecting communication channels against illegal access and eavesdropping has become crucial due to the exponential expansion of the IoT. The IoT implementations frequently have weak, unencrypted data streams that are susceptible to manipulation and interception. In order to overcome this, the proposed work incorporates lightweight protection using Moving Picture Experts Group (MPEG) derived motion vectors and dual encryption techniques to guarantee message confidentiality and integrity via limited IoT networks. The proposed method starts with resizing MPEG video frames to dimensions [1080, 1920]. After extracting motion vectors from two successive video frames, scale the obtained vectors to 1000. The exclusive OR (XOR) procedure is applied to the combined motion vectors. A one-dimensional (1D) vector is then produced. The initial elliptic curve Diffie-Hellman (ECDH) private key is created using a mapping of a hash function. The public keys, shared secret keys, and a second private key are also created. The shared secret key is used to generate the Advanced Encryption Standard (AES) main key. After that, the created AES is used to encrypt and decrypt text messages ranging in length from 10 to 300 bytes. Several evaluation metrics, including mean square error (MSE), peak signal to noise ratio (PSNR), correlation coefficient (CC), avalanche Effect (AE), and compression ratio (CR) values, are evaluated between the original and ciphertext. The presented method has demonstrated optimal performance in terms of encryption and decryption times as well as public and private key generation. Thus, improving the IoT application’s overall security condition by guaranteeing that only authorized endpoints can decrypt and read the data, and showing minimal latency overhead as compared to insecure transmission. This suggests that it is a highly effective solution for secure text communication, offering lightweight encryption suitable for a wide range of resource-constrained and real-time applications.

The search for more sustainable reaction conditions has been necessary to obtain more selective processes. In this context, laccases have gained great notoriety in recent years. However, these enzymes are unstable in organic solvents and have low thermal stability. Alternatively, conjugation with PEG (PEGylation) can be essential to overcome these problems. In this work, the commercial laccase from Myceliophthora thermophila (LacMT) was subjected to PEGylation with PEG functionalized as succinimidyl carbonate (mPEG-SC), followed by assessing its thermal stability and catalytic activity. Mono-PEGylated LacMT derivatives were obtained, with less than 50% of the enzyme remaining in its native form. In addition, 10% of the bi-PEGylated species was successfully obtained according to gel electrophoresis analysis. The PEGylated derivatives showed a significantly reduced ABTS oxidation activity (98 ± 3 U/mg) compared to the native LacMT (407 ± 9 U/mg) but higher than the control enzyme without PEGylation (51 ± 2 U/mg), demonstrating that the addition of activated PEG to the protein resulted in better protection against the harmful action of the pH change required in the process. PEGylated LacMT retained more than twice the initial activity of the native protein at 40 °C during 24 h. In addition, PEGylated LacMT exhibited kinetic changes, whereas the catalytic turnover rate (kcat) of the PEGylated enzyme was reduced by 27% compared to the control. These findings are being reported for the first time. This sets precedents for constructing efficient catalytic systems involving laccases since no immobilized biocatalyst or commercial conjugate contains these proteins.

To deal with the coming Multi-access Edge Computing (MEC)-based 5G and the future 6G wireless mobile network environment, a Multi-access Edge Computing (MEC)-based video streaming method using the proposed quality-aware video bitrate adaption and MEC server handoff control mechanisms for Dynamic Adaptive Streaming over HTTP (MPEG-DASH) video streaming was proposed in this work. Since the user is moving, the attached Base Station (BS) of the cellular network can be changed, i.e., the BS handoff can happen, which results in the corresponding MEC server handoff. Thus, this work proposed the MEC server handoff control mechanism to make the playing quality be smooth when the MEC server handoff happens. To have the MEC server to be able to derive the video bit rate for each video segment of the MPEG-DASH video streaming and to have the smooth video streaming when the MEC server handoff happens, the proposed method (i) derives the estimated bandwidth using the adaptive filter mechanism, (ii) generates some candidate video bit rates by considering the estimated bandwidth and the buffer occupancy situation in the client side and then (iii) selects a video bit rate from the candidate ones considering video quality’s stability. For the video quality’s stability concern, the proposed method considered not only (i) both bandwidth and buffer issues but also (ii) the long-term quality variation and the short-term quality variation to have the adaptive video streaming. The results of the performance evaluation, which was executed in a lab-wide experimental LTE network eNB system, shown that the proposed method has the more stable video quality for the MPEG-DASH video streaming over the wireless mobile network.

In this research, the antibacterial effect of curcumin entrapped in polymeric nanoparticles (mPEG-PCL/curcumin) on resistant bacteria were investigated. Ring-opening polymerization method was used for the synthesis of mPEG-PCL copolymers at 120 °C. mPEG-PCL and Sn (Oct)2 were used as initiator/catalyst respectively. Curcumin loaded polymeric nanoparticles were prepared using the nanoprecipitation method. The particle size and zeta potential of mPEG-PCL/curcumin were found to be 111.16 ± 3.26 nm and − 5.67 ± 5.26 mv, respectively. TEM, AFM, FTIR and DSC were used to determine the structure of polymeric nanoparticles. The impact of mPEG-PCL/curcumin on wild (w) and standard (s) strains in bacterial media was assessed through the procedures of turbidity assay and colony-forming based on units per milliliter (CFU/mL). The impact of mPEG-PCL/curcumin on wild (w) strains in main wastewater was assessed by colony-forming based on units per milliliter (CFU/mL). mPEG-PCL/curcumin at a concentration of 40 µM had a stronger effect on wild strains of bacteria at 37 °C. However, examination of the performance of mPEG-PCL/curcumin in wastewater showed that mPEG-PCL/curcumin can reduce the total microbial total count at a concentration of 0.125 µM and at 25 °C.