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Multi-Scale Hydrogen Bonding and Microphase Separation Synergistically Engineered Polyurethane-Polyurea (PU-PUa) as High-Performance Binder.

Driven by the rising frequency of extreme climatic events and the escalating demand for sustainable infrastructure, modern pavement materials must deliver enhanced resilience, structural stability, and environmental adaptability. This study presents the design and synthesis of a novel polyurethane-polyurea (PU-PUa) pavement binder, engineered via a synergistic framework combining nanoscale microphase separation and a hierarchical hydrogen-bonding network. Utilizing a streamlined, one-step synthesis approach involving an aliphatic isocyanate, a polyaspartic ester, polytetramethylene ether glyco

The in vivo evaluation of tissue-based biomaterials in a rat full-thickness abdominal wall defect model.

Hernias are defects in which an anatomical fascia is breached resulting in ectopic positioning of an organ into an orifice which routinely does not contain it. Intervention often involves repositioning translocated organs and repair of damaged fascia using exogenous grafts. Despite hernia prevalence, repairs can still fail due to postoperative complications, such as chronic pain and decreased mobility. This study compared repair capacities and characterized the foreign body response elicited by a number of hernia repair grafts to deduce their bulk inflammatory properties while also concluding

Developmental toxicity of 1,6-hexamethylene diisocyanate (HDI) in the Sprague-Dawley rat.

BACKGROUND: 1,6-Hexamethylene diisocyanate (HDI), a widely used chemical in commercial polyurethane manufacture, has been shown to affect the respiratory tract of experimental animals. However, its potential to affect neonatal development, particularly after inhalation exposure, is less well described. The present study was conducted to assess the developmental toxicity of HDI. METHODS: Gravid Sprague-Dawley rats were exposed to concentrations of 0, 0. 005, 0.050, or 0.300 ppm HDI via inhalation (whole-body exposure) on days 0-19 of gestation. Maternal toxicity, as demonstrated by clinical si

Hyperbranched Organosilicon Polymer-Based Transparent Hybrid Antifouling Coating with Active-Passive Synergistic Antibacterial Action.

Polydimethylsiloxane (PDMS)-based fouling-release coatings perform poorly in static conditions due to their lack of antifouling mechanisms like biocidal activity or surface repellence. The high melt viscosity, limited chain-end functional groups, and lack of intermolecular interactions of linear PDMS chains lead to challenges such as impaired processability, reduced adhesion to substrates, and diminished toughness and tear resistance. To overcome these drawbacks, this study strategically integrates hyperbranched polymers with relatively long branches and rigid adamantane skeletons into a hybri

Alternative monomer for BisGMA-free resin composites formulations.

OBJECTIVE: Water sorption, high volumetric shrinkage, polymerization stress, and potential estrogenic effects triggered by leached compounds are some of the major concerns related to BisGMA-TEGDMA co-monomer systems used in dental composites. These deficiencies call for the development of alternative organic matrices in order to maximize the clinical lifespan of resin composite dental restorations. This study proposes BisGMA-free systems based on the combination of UDMA and a newly synthesized diurethane dimethacrylate, and evaluates key mechanical and physical properties of the resulting mate

Exposure Risks and Potential Control Measures for a Fire Behavior Lab Training Structure: Part B. Chemical Gas Concentrations.

Firefighters' or instructors' exposure to airborne chemicals during live-fire training may depend on fuels being burned, fuel orientation and participants' location within the structure. This study was designed to evaluate the impact of different control measures on exposure risk to combustion byproducts during fire dynamics training where fuel packages are mounted at or near the ceiling. These measures included substitution of training fuels (low density wood fiberboard, oriented strand board (OSB), pallets, particle board, plywood) and adoption of engineering controls such as changing the lo

Ketoprofen glucuronidation and bile excretion in carbon tetrachloride and alpha-naphthylisothiocyanate induced hepatic injury rats.

A pharmacokinetic study was carried out in rats to investigate the effects of experimental hepatic injury on the liver glucuronidation and bile excretion of ketoprofen (KP) and its glucuronides (KPGs). In vivo, KP (20mg/kg b.w.) was intravenously administered to carbon tetrachloride (CCl(4)) or alpha-naphthylisothiocyanate (ANIT) induced hepatic injury male rats. Concentrations of KP and its glucuronides (S-KPG and R-KPG) in plasma and bile were determined by RP-HPLC. It was observed that there was significant difference in the accumulative bile excretion of KPGs between the CCl(4) intoxicated

Frentizole, a Nontoxic Immunosuppressive Drug, and Its Analogs Display Antitumor Activity via Tubulin Inhibition.

Antimitotic agents are one of the more successful types of anticancer drugs, but they suffer from toxicity and resistance. The application of approved drugs to new indications (i.e., drug repurposing) is a promising strategy for the development of new drugs. It relies on finding pattern similarities: drug effects to other drugs or conditions, similar toxicities, or structural similarity. Here, we recursively searched a database of approved drugs for structural similarity to several antimitotic agents binding to a specific site of tubulin, with the expectation of finding structures that could f

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… We unsuccessfully attempted the synthesis of the unsubstituted ureas 2 by the reaction of the 2-amino benzothiazoles with chlorosulfonyl isocyanate or potassium cyanate in different conditions. … Substituted ureas 5 , 6 , and 7 were prepared by reaction of the 2-aminobenzothiazoles with ethyl ( 5 ), phenyl ( 6 ), and benzyl ( 7 ) isocyanates. …

[Influence of transforming growth factor-beta1 on actin in cultured human trabecular cells].

OBJECTIVE: To understand transforming growth factor-beta(1) (TFG-beta(1)) influencing microfilament actins in cultured human trabecular cells (HTCs) and approach to the effect of resistance of aqueous outflow in the pathogenesis and mechanism of primary open angle glaucoma (POAG). METHODS: Trabecular meshwork was collected from 68 eyeballs of 34 human donors under 6 years old within 24 hours after death. HTCs were primarily cultured and subcultured. Cultured cells were observed by light and electron microscopes. Laminin (LN) and IVcollagen (IVC) in extracellular matrix (ECM) were immunohistoc

Green, facile synthesis and evaluation of unsymmetrical carbamide derivatives as antimicrobial and anticancer agents with mechanistic insights.

A very practical method for the synthesis of unsymmetrical carbamide derivatives in good to excellent yield was presented, without the need for any catalyst and at room temperature. Using a facile and robust protocol, fifteen unsymmetrical carbamide derivatives (9-23) bearing different aliphatic amine moieties were designed and synthesized by the reaction of secondary aliphatic amines with isocyanate derivatives in the presence of acetonitrile as an appropriate solvent in good to excellent yields. Trusted instruments like IR, mass spectrometry, NMR spectra, and elemental analyses were employed

Synthesis, Characterization, and Biological Studies of Biopolyurethane-Chitosan Composites Based on Diphenylmethane Diisocyanate and Polyol Derived from Castor Oil for the Development of Biomaterials for Topical Use.

Polyurethanes (PUs) are polymers that have aroused considerable interest in the medical and tissue engineering fields due to their physicochemical properties, such as mechanical and thermal stability, elasticity, and biocompatibility. PUs have been used in the manufacturing of medical devices since the 1960s, such as catheters, artificial hearts, and blood bags. This class of polymers is synthesized from the polyaddition reaction of a polyol (soft segment) with a diisocyanate (hard segment). In view of the tendency to replace polyols derived from fossil resources with those derived from renewa

Synthesis and reactivity of calix[4]arene-supported group 4 imido complexes.

New mononuclear titanium and zirconium imido complexes [M(NR)(R'(2)calix)] [M=Ti, R'=Me, R=tBu (1), R=2,6-C(6)H(3)Me(2) (2), R=2,6-C(6)H(3)iPr(2) (3), R=2,4,6-C(6)H(2)Me(3) (4); M=Ti, R'=Bz, R=tBu (5), R=2,6-C(6)H(3)Me(2) (6), R=2,6-C(6)H(3)iPr(2) (7); M=Zr, R'=Me, R=2,6-C(6)H(3)iPr(2) (8)] supported by 1,3-diorganyl ether p-tert-butylcalix[4]arenes (R'(2)calix) were prepared in good yield from the readily available complexes [MCl(2)(Me(2)calix)], [Ti(NR)Cl(2)(py)(3)], and [Ti(NR)Cl(2)(NHMe(2))(2)]. The crystallographically characterised complex [Ti(NtBu)(Me(2)calix)] (1) reacts readily with C

Общий синтез циклогельминтола I-IV свидетельствует о создании новой цистейно-селективной ковалентной реакционной группы.

Биосопоставимые кавалентные реактивные группы (КРГ) играют ключевую роль в ряде областей химической биологии и биологических наук, включая целевую ковалентную ингибиторную конструкцию и подготовку современных биологовых препаратов, таких, как антитела-наркотики. В этом исследовании мы представляем информацию о том, что небольшой хлорированный естественный продукт из поликетида циклогельминтиол II (CHM-II) действует в качестве нового типа CRG, предусматривающего как обратимую, так и необратимую реактивность. Мы разрабатываем первые синтезы из четырех простых циклогельминтолов, циклохелминтола I

Antiseptic Functions of CGK012 against HMGB1-Mediated Septic Responses.

High mobility group box 1 (HMGB1), a protein with important functions, has been recognized as a potential therapeutic target for the treatment of sepsis. One possible mechanism for this is that inhibiting HMGB1 secretion can exert antiseptic effects, which can restore the integrity of the vascular barrier. (7S)-(+)-cyclopentyl carbamic acid 8,8-dimethyl-2-oxo-6,7-dihydro-2H,8H-pyrano[3,2-g]chromen-7-yl-ester (CGK012) is a newly synthesized pyranocoumarin compound that could function as a novel small-molecule inhibitor of the Wnt/β-catenin signaling pathway. However, no studies have yet determi

Advancement of NF-κB Signaling Pathway: A Novel Target in Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers and is the third highest among cancer related deaths. Despite modest success with therapy such as gemcitabine, pancreatic cancer incidence remains virtually unchanged in the past 25 years. Among the several driver mutations for PDAC, Kras mutation contributes a central role for its development, progression and therapeutic resistance. In addition, inflammation is implicated in the development of most human cancer, including pancreatic cancer. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is recogniz

NTP Toxicology and Carcinogenesis Studies of 3,3'-Dimethoxybenzidine Dihydrochloride (CAS No. 20325-40-0) in F344/N Rats (Drinking Water Studies).

3,3'-Dimethoxybenzidine dihydrochloride is an off-white powder with a melting point of 274 degrees C. 3,3'-Dimethoxybenzidine is used principally as an intermediate in the production of commercial bisazobiphenyl dyes for coloring textiles, paper, plastic, rubber, and leather. In the synthesis of the bisazobiphenyl dyes, the amine groups of 3,3'-dimethoxybenzidine are chemically linked with other aromatic amines. A small quantity of 3,3'-dimethoxybenzidine is also used as an intermediate in the production of o-dianisidine diisocyanate, which is used in isocyanate-based adhesive systems and as a

A Preliminary Investigation towards the Risk Stratification of Allogeneic Stem Cell Recipients with Respect to the Potential for Development of GVHD via Their Pre-Transplant Plasma Lipid and Metabolic Signature.

The clinical outcome of allogeneic hematopoietic stem cell transplantation (SCT) may be influenced by the metabolic status of the recipient following conditioning, which in turn may enable risk stratification with respect to the development of transplant-associated complications such as graft vs. host disease (GVHD). To better understand the impact of the metabolic profile of transplant recipients on post-transplant alloreactivity, we investigated the metabolic signature of 14 patients undergoing myeloablative conditioning followed by either human leukocyte antigen (HLA)-matched related or unr

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… Inactivation of glutathione reductase by 2-chloroethyl nitrosourea-derived isocyanates. Biochem. Biophys. Res. Commun. 1978;83:754–762. doi: 10.1016/0006-291X(78)91053-7. 38. Buck M.D., Pearce E.L., O’Sullivan D., O’Sullivan D. T cell metabolism drives immunity. J. Exp. …

Amelioration of the cyclophosphamide induced genotoxic damage in mice by the ethanolic extract of Equisetum arvense.

In the present study, we evaluated the potential of the plant E. arvense against the cytotoxic and mutagenic effects induced by cyclophosphamide (chemotherapeutic agent) in the bone marrow cells of mice using the Chromosome assay (CA) and Mitotic index (MI) in vivo as the biomarkers. The study was performed following 3 protocols: pre-treatment, simultaneous treatment and post-treatment with the ethanolic extract of the plant. The results demonstrated that the plant extract was not cytotoxic and mutagenic and has a protective effect against the mutagenicity induced by cyclophosphamide in pre, s

DNA Binding, DNA Photocleavage, Molecular Docking Studies and Photo-Induced Effect on Melanoma Cells of 2-Methyl-3-OR Quinazolinone Derivatives.

Thirty 2-methyl-quinazolinone fussed hydroxamic acids (3-OH) and their 3-OEt and 3-OBn derivatives were evaluated for their affinity towards calf-thymus (CT) DNA using UV-vis absorption, viscosity and fluorescence spectroscopy. DNA photocleavage activity was assessed by incubating the compounds with plasmid DNA followed by UV-A and visible light irradiation, which enabled identification of the most potent derivatives active at concentrations of 100 nΜ and 10 μΜ, respectively. Mechanistic studies on the most active compounds indicated the formation of oxygen radical species and a decrease in ef

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… Despite their potential as drugs, HMAs have shown mutagenic properties in vitro, as they can interact with DNA and may be transformed into toxic isocyanates via the Lossen rearrangement [ 9 , 16 , 17 ]. …

Translational nanoparticle engineering for cancer vaccines.

Conventional cancer treatments remain insufficient to treat many therapy-resistant tumors.1 Cancer vaccines attempt to overcome this resistance by activating the patient's immune system to eliminate tumor cells without the toxicity of systemic chemotherapy and radiation. Nanoparticles (NPs) are promising as customizable, immunostimulatory carriers to protect and deliver antigen. Although many NP vaccines have been investigated in preclinical settings, a few have advanced into clinical application, and still fewer have demonstrated clinical benefit. This review incorporates observations from NP