Superabsorbent polymers: A state-of-art review on their classification, synthesis, physicochemical properties, and applications

Superabsorbent polymers (SAP) and modified natural polymer hydrogels are widely and increasingly used in agriculture, health care textiles, effluent treatment, drug delivery, tissue engineering, civil concrete structure, etc. However, not many comprehensive reviews are available on this class of novel polymers. A review covering all the viable applications of SAP will be highly useful for researchers, industry persons, and medical, healthcare, and agricultural purposes. Hence, an attempt has been made to review SAPs with reference to their classifications, synthesis, modification by crosslinking, and physicochemical characterization such as morphology, swellability, thermal and mechanical properties, lifetime prediction, thermodynamics of swelling, absorption, release and transport kinetics, quantification of hydrophilic groups, etc. Besides, the possible methods of fine-tuning their structures for improving their absorption capacity, fast absorption kinetics, mechanical strength, controlled release features, etc. were also addressed to widen their uses. This review has also highlighted the biodegradability, commercial viability and market potential of SAPs, SAP composites, the feasibility of using biomass as raw materials for SAP production, etc. The challenges and future prospects of SAP, their safety, and environmental issues are also discussed.

How 10 at% Al Addition in the Ti-V-Zr-Nb High-Entropy Alloy Changes Hydrogen Sorption Properties

Al0.10Ti0.30V0.25Zr0.10Nb0.25 was prepared to evaluate the effect of 10% aluminum into the previously reported quaternary alloy, Ti0.325V0.275Zr0.125Nb0.275. The as-cast quinary alloy formed a single-phase body centered cubic solid solution and transformed into a body centered tetragonal after hydrogenation. The alloy had a storage capacity of 1.6 H/M (2.6 wt.%) with fast absorption kinetics at room temperature, reaching full capacity within the first 10 min. The major improvements of Al addition (10%) were related to the desorption and cycling properties of the material. The temperature for hydrogen release was significantly decreased by around 100 °C, and the quinary alloy showed superior cycling stability and higher reversible storage capacity than its quaternary counterpart, 94% and 85% of their respective initial capacity, after 20 hydrogenation cycles without phase decomposition.

Recent Advances in Small Peptides of Marine Origin in Cancer Therapy

Cancer is one of the leading causes of death in the world, and antineoplastic drug research continues to be a major field in medicine development. The marine milieu has thousands of biological species that are a valuable source of novel functional proteins and peptides, which have been used in the treatment of many diseases, including cancer. In contrast with proteins and polypeptides, small peptides (with a molecular weight of less than 1000 Da) have overwhelming advantages, such as preferential and fast absorption, which can decrease the burden on human gastrointestinal function. Besides, these peptides are only connected by a few peptide bonds, and their small molecular weight makes it easy to modify and synthesize them. Specifically, small peptides can deliver nutrients and drugs to cells and tissues in the body. These characteristics make them stand out in relation to targeted drug therapy. Nowadays, the anticancer mechanisms of the small marine peptides are still largely not well understood; however, several marine peptides have been applied in preclinical treatment. This paper highlights the anticancer linear and cyclic small peptides in marine resources and presents a review of peptides and the derivatives and their mechanisms.

Monogenic diabetes: a new pathogenic variant of HNF1A gene

Maturity onset diabetes of the young defines a diabetes mellitus subtype, with no insulin resistance or autoimmune pancreatic β-cells dysfunction, that occurs by mutation in a single gene. A 13-year-old girl hospitalised due to hyperglycemia plus glycosuria without ketosis, and with normal glycated haemoglobin of 6.8%. She started a sugar-free fast-absorption diet and no insulin therapy was required. Fasting glucose was normal, but 2 hours after lunch she presented hyperglycemia as after 2 hours of an oral glucose tolerance test, with 217 mg/dL. Family history was positive for type 2 diabetes mellitus with an autosomal dominant pattern. She was discharged with fast-absorption sugar-free diet and low-dose of sulfonylurea. A genetic test was performed detecting a mutation in heterozygosity of HNF1A gene, compatible with the diagnosis of maturity onset diabetes of the young 3 (MODY3), not reported in the literature. Early recognition of signs and symptoms increase awareness of MODY. Genetic test allows confirmation and leads to optimised treatment.

Pharmacodynamic evaluation of Dezocine injection from Yangtze River Pharmaceutical Group

Intramuscular injection and intravenous injection are important routes of drug administration, which not only have a fast absorption rate, but also avoid the first pass effect of the drug. In 2009, Yangtze Pharmaceutical Group redeveloped Dezocine(13-Amino-5,6,7,8,9,10,11,12-octahydro-5-methyl-5,11-methanobenzocyclodecen-3-ol), molecular formula: C16H23NO, in the form of njection. Quickly, Dezocine injection becomes the first choice for perioperative pain management in China and accounts for 45 % of the analgesic market. This study mainly used animal pain models to study the analgesic effects of Dezocine injection. The results indicated that Dezocine produced potent analgesic effect in the hot plate and writhing tests.

An ethanethioate functionalized polythiophene as optical probe for sensitive and fast detection of water content in organic solvents

A new polythiophene-based optical probe, namely PTS, was designed and prepared for detection and quantification of the water present in organic solvents. PTS exhibited sensitive and fast absorption and fluorescence...

Oxytetracycline Pharmacokinetics After Intramuscular Administration in Cows with Clinical Metritis Associated with Trueperella Pyogenes Infection

Systemic therapy with oxytetracycline is often used for treatment of clinical metritis although data about its penetration into the uterus and uterine secretion are lacking. Uterine secretions and milk from six cows with clinical metritis were collected for microbiological assay. The animals were treated intramuscularly with long-acting oxytetracycline (20 mg/kg) and samples of plasma, milk and uterine secretions were collected for determination of the antibiotic concentrations by HPLC-PDA analysis. Pharmacokinetics of the antibiotic and in silico prediction of its penetration into the uterus were described. Trueperella pyogenes with MIC values of 16–64 µg mL−1 was isolated (n of cows = 4) from uterine secretions. Oxytetracycline showed fast absorption and penetration in the uterine secretions and milk. No change of withdrawal time for milk was necessitated in cows with clinical metritis. Maximum levels in uterine secretions and predicted concentrations of oxytetracycline in the uterus were lower than MIC values. Systemic administration of long-acting oxytetracycline did not guarantee clinical cure and was not a suitable choice for treatment of clinical metritis associated with Trueperella pyogenes. The appropriate approach to antibiotic treatment of uterine infections of cows requires knowledge on penetration of the antibiotics at the site of infection and sensitivity of pathogens.

Hydrogen Storage Properties of Mg-Ni Alloys Processed by Fast Forging

Fast forging of compacts made up of Mg and Ni powders is shown to be an effective method to induce severe plastic deformation with improved H2 sorption properties. Here, using such processed samples, a comprehensive analysis of the sorption properties reveals that the first hydrogenation sequence significantly depends on the forging temperature, through different microstructures. More in detail, no phase transformation occurs upon cold forging, while solid-state reaction leads to the formation of the Mg2Ni intermetallic compound upon forging above 400 °C. Forging below the brittle-to-ductile transition (225–250 °C) leads to faster H2 uptake upon first absorption owing to a more textured fiber along the c-axis and internal strains which promote hydrogen diffusion through the bulk material. Desorption kinetics remain slower with low-temperature forging, despite Ni recombining to form Mg2Ni during the first desorption. After several cycles, a two-step behavior is observed with a fast absorption step occurring up to about 3 wt.%. Despite this limited uptake performance, the forging process can be considered as a straightforward, safe, and cost-efficient process to produce large amounts of Mg-based alloys for hydrogen storage. In particular, such severe plastic deformation processes can be considered as reliable substitutes for ball-milling, which is highly efficient but energy- and time-consuming.

Anthelmintic Activity of Yeast Particle-Encapsulated Terpenes

Soil-transmitted nematodes (STN) infect 1–2 billion of the poorest people worldwide. Only benzimidazoles are currently used in mass drug administration, with many instances of reduced activity. Terpenes are a class of compounds with anthelmintic activity. Thymol, a natural monoterpene phenol, was used to help eradicate hookworms in the U.S. South circa 1910. However, the use of terpenes as anthelmintics was discontinued because of adverse side effects associated with high doses and premature stomach absorption. Furthermore, the dose–response activity of specific terpenes against STNs has been understudied. Here we used hollow, porous yeast particles (YPs) to efficiently encapsulate (>95%) high levels of terpenes (52% w/w) and evaluated their anthelmintic activity on hookworms (Ancylostoma ceylanicum), a rodent parasite (Nippostrongylus brasiliensis), and whipworm (Trichuris muris). We identified YP–terpenes that were effective against all three parasites. Further, YP–terpenes overcame albendazole-resistant Caenorhabditis elegans. These results demonstrate that terpenes are broad-acting anthelmintics. Terpenes are predicted to be extremely difficult for parasites to resist, and YP encapsulation provides water-suspendable terpene materials without surfactants and sustained terpene release that could lead to the development of formulations for oral delivery that overcome fast absorption in the stomach, thus reducing dosage and toxic side effects.

Formulation and Optimization of Avanafil Biodegradable Polymeric Nanoparticles: A Single-Dose Clinical Pharmacokinetic Evaluation

Avanafil (AVA) is a second-generation phosphodiesterase-5 (PDE5) inhibitor. AVA shows high selectivity to penile tissues and fast absorption, but has a bioavailability of about 36%. The aim was to formulate and optimize AVA-biodegradable nanoparticles (NPs) to enhance AVA bioavailability. To assess the impact of variables, the Box–Behnken design was utilized to investigate and optimize the formulation process variables: the AVA:poly (lactic-co-glycolic acid) (PLGA) ratio (w/w, X1); sonication time (min, X2); and polyvinyl alcohol (PVA) concentration (%, X3). Particle size (nm, Y1) and EE% (%, Y2) were the responses. The optimized NPs were characterized for surface morphology and permeation. Furthermore, a single-oral dose (50 mg AVA) pharmacokinetic investigation on healthy volunteers was carried out. Statistical analysis revealed that all the investigated factors exhibited a significant effect on the particle size. Furthermore, the entrapment efficiency (Y2) was significantly affected by both the AVA:PLGA ratio (X1) and PVA concentration (X3). Pharmacokinetic data showed a significant increase in the area under the curve (1.68 folds) and plasma maximum concentration (1.3-fold) for the AVA NPs when compared with raw AVA. The optimization and formulation of AVA as biodegradable NPs prepared using solvent evaporation (SE) proves a successful way to enhance AVA bioavailability.