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• Flow characteristics of silica hard-shell microcapsules with phase change materials have been improves with surfactants. • Combination additives of surfactants and of poly vinyl alcohol well depress the sedimentation of microcapsules with PCM. • The addition of poly vinyl alcohol does not disturb drag-reducing effect of the surfactants. The sedimentation and flow characteristics of micro-encapsulated phase change materials have been investigated. As a phase change material, trimethylolethane clathrate hydrate having 218 kJ kg−1 of latent heat was used and encapsulated in silica hard-shell microcapsules, which size distribution has two peak at 15 µm and 59 µm. A cationic surfactant, oleylbishydroxyethylmethylammonium chloride with a counter-ion, sodium salicylate was used as drag reducing additives and poly vinyl alcohol was used as a stabilizer. From the results, it was found that the combination additive prevents effectively the microcapsule sedimentation. The drag reduction was also observed to occur in the high Reynolds number region. Thus, the present additive was concluded to be promising for the latent heat transportation by use of silica hard-shell microcapsules containing phase change materials. [ABSTRACT FROM AUTHOR]

• Electropolymerized dopamine (ePDA) coating was prepared on Mg-Zn-Y-Nd alloy surface. • ePDA coating surface is uniform and doped with salicylate and magnesium. • ePDA coating induced more uniform surface of Poly (l -lactic acid) (PLLA) coating than dip polydopamine (dPDA) coating. • ePDA/PLLA coating showed excellent adhesion and higher corrosion resistance than dPDA/PLLA coating. The high surface roughness of dip polydopamine (dPDA) coating on magnesium alloy could decrease the quality of secondary modification. In the present study, we report an electropolymerized dopamine (ePDA) coating on Mg-Zn-Y-Nd alloy from sodium salicylate aqueous solutions by galvanostat method to address this problem. The coating formation process and coating structure were investigated. Then, a Poly (l -lactic acid) (PLLA) coating was prepared on ePDA and dPDA treated samples. The SEM results reveal that the ePDA film appeared to be more uniform than dPDA coating and was doped with salicylate and magnesium ions. ASTM D3359 -09 "Tape test" shows excellent adhesion of the ePDA/PLLA layer. The electrochemical impedance spectroscopy and polarization curves demonstrate ePDA/PLLA film has a better corrosion resistance than dPDA/PLLA film, owing to the structural difference of polydopamine anchoring layer. [ABSTRACT FROM AUTHOR]

In order to elucidate the possibility of the formation and enzymatic dissociation of worm-like micelles (WLMs) from long-chain alkanoylcholines (LCACs), strategies of fabrication and butyrylcholine esterase (BChE)-catalyzed dissociation of LCAC-based WLMs have been developed. Three LCACs with different hydrophobic tail lengths, namely dodecanoylcholine bromide (DCB), myristoylcholine bromide (MCB), and palmitoylcholine bromide (PCB), have been used as model cationic surfactants. It was demonstrated that the hydrophobic tail length of an LCAC played an important role in the formation of WLMs. With the assistance of sodium salicylate (NaSal), DCB proved to be incapable of efficiently forming WLMs, whereas MCB and PCB performed well. PCB-based WLMs have also been fabricated with the aid of NaNO 3. To fabricate WLMs at a surfactant concentration of 0.1 mol L−1, the optimal molar ratio of the additive (NaSal and NaNO 3) to the surfactant (MCB and PCB) was around 0.83 (NaSal/MCB), 0.63 (NaSal/PCB) and 20 (NaNO 3 /PCB), respectively. The respective average diameters of the WLMs were about 4.11 nm (MCB-NaSal), 4.82 nm (PCB-NaSal), and 4.51 nm (PCB-NaNO 3). Meanwhile, the respective zero-shear viscosities of the WLMs were about 5.38 × 102 mPa s (MCB-NaSal), 1.81 × 105 mPa s (PCB-NaSal), and 7.35 × 104 mPa s (PCB-NaNO 3). Jelly-like PCB-NaSal and PCB-NaNO 3 WLMs underwent efficient dissociation through a BChE-catalyzing strategy under mild conditions of pH 7.4 and 37 °C. Its chemical principle was a hydrolysis reaction of PCB catalyzed by BChE. [Display omitted] [ABSTRACT FROM AUTHOR]

• Preparation of CO 2 -stimulus-responsive WLMs for stabilization of CO 2 foam flooding systems. • Exploring the seepage law of WLM-CO 2 foam in porous media. • Obtain a CO 2 foam flooding system that is beneficial to the treatment of produced-fluid. The stability of CO 2 foam seriously restricts its stimulation effect in low-permeability reservoirs, and the presence of foaming agents and foam stabilizers in the system will make the production fluid treatment more difficult. Therefore, in response to the above problems, this paper prepared a CO 2 -responsive worm-like micelles (WLMs) using N,N-dimethyl oleoaminde-propylamine (DOAPA) and sodium salicylate (NaSaI) as raw materials, and investigated its foam performance, fluidity-control ability, oil-displacement performance, microscopic-seepage law, and microcosmic, demulsification and defoaming analysis of the simulated produced-fluid. Experimental results showed that DOAPA-H+ increased the viscosity and stability of the foam-based solution under the action of organic salt. In homogeneous and heterogeneous models, worm-like micelle CO 2 foam (DOAPA@NaSaI-H+) enhance oil recovery (EOR) by 26.2% and 27.3%, respectively, which were about 1.5 times that of traditional CO 2 foam. After injecting N 2 into the production fluid, the system can realize rapid and pollution-free demulsification and defoaming. The research shows that DOAPA@NaSaI-H+ has great potential to EOR and reduce the difficulty of production-fluid treatment, which provides a new idea for low permeability reservoirs combined with CO 2 resource utilization and storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fluorinated azobenzene transforms spherical micelles into cylindrical micelles with a disk-like cross-section. • Thread-like structures formed by the concatenation of disk-like micelles. • Discoidal micelles concatenate forming thread-like structures similar to worm-like micelle structures. The free energy in solutions of amphiphilic molecules leads to the formation of supramolecular structures, often making spherical aggregates, worm-like micelles, vesicles, and lamellae. In this work, we add a fluorinated azobenzene, 4-(4-trifluoromethoxy phenyl azo) phenol (Azo-3F) to a solution mainly made of spherical and rodlike micelles of CetylTrimethylAmmonium Bromide (CTAB) and sodium salicylate (NaSal). These structures transform to disk-like micelles, which concatenate through hydrogen bridges to form long thread-like structures highly similar to worm-like micelle structures. This conclusion was reached after observing that NMR results suggest the formation of aggregates in solution with Azo-3F molecules inside them. Viscosity increases by three orders of magnitude at low shear rates when Azo-3F is added, and it shear-thins as the shear rate increases. The viscoelastic spectra show that the fluid changes from viscous to viscoelastic. Cole-Cole plots follow semicircles, typical of Maxwellian behavior below ∼ 35 °C. Cryo-TEM micrographs of the solution with Azo-3F show giant thread-like structures, and cross-sectional analysis of SAXS and WAXS profiles predict oblate ellipsoidal structures. In addition, MD simulations show that the disk-like micelles interact mainly through hydrogen bonds and electrostatics, forming micellar strings. These strings behave similarly to worm-like micelles, explaining why the solution behaves as a Maxwellian fluid at relatively low temperatures. Consequently, when some specific molecules are introduced in supramolecular structures, such as a spherical micelle, they can be transformed into disk-like micelles that assemble into thread-like micelles. [ABSTRACT FROM AUTHOR]

Schistosomiasis is a major public health concern worldwide. Although praziquantel is currently available as the only treatment option for schistosomiasis, the absence of reliable diagnostic and prognostic tools highlights the need for the identification and characterization of new drug targets. Recently, we identified the B. glabrata homolog (accession number XP_013075832.1) of human CAXIV, showing 37% amino acid sequence identity, from a BLAST search in NCBI (National Center for Biotechnology Information). Carbonic Anhydrases (CAs) are metalloenzymes that catalyze the reversible hydration/dehydration of CO 2 /HCO 3. These enzymes are associated with many physiological processes, and their role in tumorigenesis has been widely implicated. CAs create an acidic extracellular environment that facilitates the survival, metastasis, and growth of cancer cells. In this study, we investigated the role of CA inhibition in B. glabrata snails exposed to S. mansoni miracidia. We analyzed the expression of the B. glabrata CA encoding transcript in juvenile susceptible and resistant snails, with and without exposure to S. mansoni. Our results showed that the expression of the CA mRNA encoding transcript was upregulated during early and prolonged infection in susceptible snails (BBO2), but not in the resistant BS-90 stock. Notably, sodium salicylate, a form of aspirin, inhibited the expression of CA, post-exposure, to the parasite. Increasing research between parasites and cancer has shown that schistosomes and cancer cells share similarities in their capacity to proliferate, survive, and evade host immune mechanisms. Here, we show that this model system is a potential new avenue for understanding the role of CA in the metastasis and proliferation of cancer cells. Further studies are needed to explore the potential of CA as a biomarker for infection in other schistosomiasis-causing parasites, including S. japonicum and S. haematobium. [Display omitted] • Carbonic Anhydrase (CA), a pH-regulating enzyme, is upregulated in S. mansoni -exposed susceptible B. glabrata snails. • Sodium salicylate, a form of aspirin, downregulates the expression of CA post-exposure to the parasite. • Daily drug treatment with sodium salicylate is a potential new avenue for inhibiting schistosomiasis. [ABSTRACT FROM AUTHOR]

Sodium salicylate (SA), a cyclooxygenase inhibitor, has been shown to increase insulin sensitivity and to suppress inflammation in obese patients and animal models. Transient receptor potential vanilloid 1 (TRPV1) is a nonselective cation channel expressed in afferent nerve fibers. Cyclooxygenase-derived prostaglandins are involved in the activation and sensitization of TRPV1. This study tested whether the metabolic and renal effects of SA were mediated by the TRPV1 channel. Wild-type (WT) and TRPV1−/− mice were fed a Western diet (WD) for 4 months and received SA infusion (120mg/kg/day) or vehicle for the last 4 weeks of WD feeding. SA treatment significantly increased blood pressure in WD-fed TRPV1−/− mice (p < 0.05) but not in WD-fed WT mice. Similarly, SA impaired renal blood flow in TRPV1−/− mice (p < 0.05) but not in WT mice. SA improved insulin and glucose tolerance in both WT and TRPV1−/− mice on WD (all p < 0.05). In addition, SA reduced renal p65 and urinary prostaglandin E2, prostaglandin F1α, and interleukin-6 in both WT and TRPV1−/− mice (all p < 0.05). SA decreased urine noradrenaline levels, increased afferent renal nerve activity, and improved baroreflex sensitivity in WT mice (all p < 0.05) but not in TRPV1−/− mice. Importantly, SA increased serum creatinine and urine kidney injury molecule-1 levels and decreased the glomerular filtration rate in obese WT mice (all p < 0.05), and these detrimental effects were significantly exacerbated in obese TRPV1−/− mice (all p < 0.05). Lastly, SA treatment increased urine albumin levels in TRPV1−/− mice (p < 0.05) but not in WT mice. Taken together, SA-elicited metabolic benefits and anti-inflammatory effects are independent of TRPV1, while SA-induced sympathetic suppression is dependent on TRPV1 channels. SA-induced renal dysfunction is dependent on intact TRPV1 channels. These findings suggest that SA needs to be cautiously used in patients with obesity or diabetes, as SA-induced renal dysfunction may be exacerbated due to impaired TRPV1 in obese and diabetic patients.

This study examined the effect of sodium salicylates (SS), alone and in combination with curcumin (CUR), on kidney function and architecture in rats. Five rat groups were given 1 mL physiological saline/rat orally, 1 mL olive oil/rat orally, 50 mg CUR/kg bwt orally, 300 mg SS/kg bwt intraperitoneally, or CUR+SS for 15 days. The hematological indices, serum protein profile, serum electrolytes balance, oxidative stress, and lipid peroxidation of kidney tissues were assessed. The histopathological examination and immune expression of Caspase-3 and nuclear factor kappa (NF-κB) were conducted. The findings showed that SS injection induced nephrotoxic activity, including increased serum urea, creatinine, and uric acid levels. It also caused apparent pathological alterations with increased Caspase-3 and NF-κB immuno-expression. In addition, thrombocytopenia, leukocytosis, neutrophilia, hyponatremia, hypochloremia, hypocalcemia, and hypomagnesemia but not hyperkalemia and hyperphosphatemia were evident in SS-injected rats. Moreover, SS exposure increased serum α1 globulin, renal tissue malondialdehyde, and Caspase-3 levels but superoxide dismutase, glutathione peroxidase, and Bcl-2 levels declined. Meanwhile, CUR significantly counteracted the SS harmful impacts on kidneys but SS+CUR co-administration induced an anemic condition. Overall, CUR has an evident protective role against SS-induced renal damage, but the disturbed hematological alterations should be carefully taken into consideration in their combined use.

The aim of this study was to investigate the effects of sodium salicylate (SS) on the preservation and metabolic regulation of sheep sperm. Under 4 °C low-temperature conditions, SS (at 10 µM, 20 µM, 30 µM, and 50 µM) was added to the semen diluent to detect sperm motility, plasma membrane, and acrosome integrity. Based on the selected optimal concentration of SS (20 µM), the effects of 20 µM of SS on sperms' antioxidant capacity and mitochondrial membrane potential (MMP) were evaluated, and metabolomics analysis was conducted. The results showed that on the 20th day of low-temperature storage, the sperm motility of the 20 µM SS group was 62.80%, and the activities of catalase (CAT) and superoxide dismutase (SOD) were significantly higher than those of the control group ( p < 0.01). The content of Ca 2+ , reactive oxygen species (ROS), and malondialdehyde (MDA) were significantly lower than those of the control group ( p < 0.01), and the total antioxidant capacity (T-AOC) was significantly higher than that of the control group ( p < 0.05); mitochondrial activity and the total cholesterol (TC) content were significantly higher than those in the control group ( p < 0.01). An ultrastructural examination showed that in the SS group, the sperm plasma membrane and acrosome were intact, the fibrous sheath and axoneme morphology of the outer dense fibers were normal, and the mitochondria were arranged neatly. In the control group, there was significant swelling of the sperm plasma membrane, rupture of the acrosome, and vacuolization of mitochondria. Using metabolomics analysis, 20 of the most significant differential metabolic markers were screened, mainly involving 6 metabolic pathways, with the amino acid biosynthesis pathway being the most abundant. In summary, 20 µM of SS significantly improved the preservation quality of sheep sperm under low-temperature conditions of 4 °C.

Hard-to-heal wounds are typically infected with biofilm-producing microorganisms, such as Pseudomonas aeruginosa, which strongly contribute to delayed healing. Due to the global challenge of antimicrobial resistance, alternative treatment strategies are needed. Here, we investigated whether inhibition of quorum sensing (QS) by sodium salicylate in different P. aeruginosa strains (QS-competent, QS-mutant, and chronic wound strains) influences biofilm formation and tolerance to silver. Biofilm formation was evaluated in simulated serum-containing wound fluid in the presence or absence of sodium salicylate (NaSa). Biofilms were established using a 3D collagen-based biofilm model, collagen coated glass, and the Calgary biofilm device. Furthermore, the susceptibility of 48-h-old biofilms formed by laboratory and clinical strains in the presence or absence of NaSa towards silver was evaluated by assessing cell viability. Biofilms formed in the presence of NaSa were more susceptible to silver and contained reduced levels of virulence factors associated with biofilm development than those formed in the absence of NaSa. Biofilm aggregates formed by the wild-type but not the QS mutant strain, were smaller and less heterogenous in size when grown in cultures with NaSa compared to control. These data suggest that NaSa, via a reduction of cell aggregation in biofilms, allows the antiseptic to become more readily available to cells.

When tetradecyltrimethylammonium bromide, TTAB, is added to aqueous solution of sodium salicylate, NaSal, the threading of the aromatic anion into the micellar palisade leads to the formation of wormlike micelles. Based on the calorimetric titration of NaSal with TTAB, and on the lifetime of fluorescence of salicylate, we propose that the aggregation of the two components directly leads to the formation of wormlike micelles, without any pre-aggregation. By using an isothermal titration calorimeter, aliquots of TTAB were added to a dilute solution of NaSal. The energy involved in each addition was then integrated and the variation of enthalpy was determined. In the same range of concentrations and molar ratios, the surface tensiometry and time-resolved emission spectroscopy experiments were performed. A very characteristic calorimetric signal associated with wormlike micelle formation was obtained, being the enthalpy variation of this process, Δ W L M H 298 0 < 0. When 1.2 mmol L−1 of NaSal is titrated with 11.0 mmol L−1 of TTAB at 298.15 K, Δ f H 298 0 = −10.31 kJ per mol of injectant. By adding TTAB to NaSal solution, two fluorescence lifetimes of salicylate were observed solely after wormlike micelle being formed. The correspondent lifetime values of 4.0 ns and 7.2 ns are respectively associated with the free and associated species of salicylate. The new results demonstrated that wormlike micelles are the first aggregate formed when TTAB is added to salicylate. This aspect is relevant for understanding the mechanism of wormlike micelles formation. [ABSTRACT FROM AUTHOR]

In this work, the influence of incorporation of two anti-inflammatory drugs dexamethasone phosphate and sodium salicylate on the electrodeposition process of polypyrrole (PPy) film on iron has been studied. The incorporation of the agents into PPy has been carried out in a one-step electropolymerization process on oxidizable iron. The role of each drug agent during the deposition process has been discussed. The morphological and redox properties of as-deposited PPy doped with salicylate only or with addition of differently concentrated dexamethasone phosphate have been examined. Moreover, a spontaneous (in literature called: self-powered) drug-release study of PPy on iron was investigated in a phosphate buffer saline solution at the body temperature by the UV-Vis spectrophotometry with the flow cell. The study showed that the addition of high molecular weight co-dopant into PPy influenced much the growth mechanism and final properties of the material. It had also a big impact on the drug release profile compared to a polymer doped only with one agent. [ABSTRACT FROM AUTHOR]

An aryl-substituted aromatic acid ionic liquid (M-X) was synthesized through hexadecyl trimethyl ammonium bromide and sodium salicylate, and it was employed as a flotation collector for the separation of quartz from magnetite. Laboratory flotation studies of magnetite and quartz were conducted using the M-X and dodecylamine (DDA) as collector. The results showed that the M-X has a stronger collecting ability and selectivity for quartz without starch. The adsorption mechanism of M-X on quartz and magnetite surfaces was studied by Fourier transform infrared spectroscopy (FTIR), zeta potential and X-ray photoelectron spectroscopy (XPS) analysis. Results indicated that the adsorption of M-X on the quartz surface was more efficient than that on the magnetite surface. And the salicylate anion in M-X was found to have depression effect to magnetite. [ABSTRACT FROM AUTHOR]

Importance: Clinical observations have implied a central origin for tinnitus and potential therapeutic effects of ascorbic acid (AA); however, the detailed mechanisms remain undetermined. Objective: To investigate changes in the AA levels and neural activity in the auditory cortex (AC) during salicylate‐induced tinnitus. Methods: Rats were randomly divided into 3 groups: (1) saline group, which received an intraperitoneal saline injection; (2) SS group, which received an intraperitoneal sodium salicylate (SS) injection (350 mg/kg); and (3) SS+Lido group, which received an intraperitoneal SS injection (350 mg/kg) and lidocaine delivered to the AC by microdialysis. For each group, we firstly used an in vivo microdialysis technique to investigate the concentrations of AA in the AC; and secondly, we recorded the neural activity in the AC using a single‐unit recording technique. Results: The AA concentration in the SS group significantly increased after SS injection, whereas that of the saline group did not change. The AA concentration in the SS+Lido group also showed an increasing trend but was significantly lower than that in the SS group. In the electrophysiological study, the spontaneous firing rate of the SS group was significantly higher than that of the saline group. In addition, the proportion of short interval discharges was also higher in the SS group than in the saline group. Both differences were reversed by lidocaine treatment. Interpretation: Our data suggest that the elevation of AA levels in the AC may be related to increased neuronal activity, which may represent the mechanism underlying salicylate‐induced tinnitus. [ABSTRACT FROM AUTHOR]

Curdlan/β-cyclodextrin (β-CD) composite hydrogels were prepared by using epichlorohydrin (ECH) and ethylene glycol diglycidyl ether (EGDGE) as cross-linkers respectively. The results showed that a macromolecular network structure was formed. This composite hydrogels showed certain temperature sensitivity, regular swelling ratio and unique mechanical property. The addition of β-CD improved the swelling property of hydrogels in neutral aqueous solution, showing completely opposite results to the cellulose/β-CD hydrogels. This composite hydrogel had certain temperature sensitivity and could sustained-release sodium salicylate for more than 8 hours. The curdlan/β-CD hydrogels, which were cross-linked by natural polymers, had a unique application prospect in the medicine. [ABSTRACT FROM AUTHOR]

The purpose of this study was to observe the regulatory effects of GABAA (γ-aminobutyric acid A) receptor on the N-methyl-d-aspartate (NMDA) receptor during excitotoxicity in spiral ganglion neurons in the rat cochlea induced by sodium salicylate (SS). Western blot illustrated SS decreased the expression of NMDA receptor 2B subunit (NR2B) surface protein through affecting GABAA receptor, but the total protein content did not significantly change. Y1472 and S1480 are important phosphorylation sites in NR2B, SS downregulated the Fyn-dependent phosphorylation of Y1472 in a manner not related to the CK2 (Casein Kinase 2) dependent phosphorylation of S1480, thus regulating the surface distribution and internalization of NMDA receptor through GABAA receptor. These results suggest that the modified pattern of dynamic balance between excitation and inhibition by coactivation of the GABAA receptor can attenuate the excitatory NMDA receptor under the action of SS, via inhibiting the Fyn-dependent phosphorylation of Y1472. [ABSTRACT FROM AUTHOR]

Intermolecular interactions are responsible for the macroscopic properties of materials. Self-assembled micelles of ionic surfactants in the presence of salt are a result of the balance between hydrophobic-hydrophilic and ionic forces. For example, sodium salicylate (NaSal) undoubtedly offers a powerful means of increasing the viscoelasticity of hexadecyl trimethylammonium bromide (CTAB) solutions by orders of magnitude, which results from the formation of wormlike micelles (WLMs). The efficiency of this additive relies on its ability to integrate and alter the repulsive interactions governing CTAB micelles. Consequently, small modifications in the molecular structure of NaSal influences the nature of these interactions. Nevertheless, the full potential of formulation for tailoring the system's viscoelasticity has yet to be unleashed. Herein, we investigate a series of structurally similar molecules varying in terms of geometry and size. The depth and molecular orientation of their insertion into the micellar core were monitored by proton nuclear magnetic resonance (1H-NMR) and correlated with the corresponding viscoelastic response. After detailed observation of the impact of molecular interactions on zero-shear viscosity η0, we discuss it in terms of the effective packing parameter (PPeff). All the investigated additives increased PPeff, triggering anisotropic micellar growth toward WLMs. The simplicity of our approach is attractive for predicting and controlling the viscoelastic properties of WLM solutions from an intermolecular level. [ABSTRACT FROM AUTHOR]

In this study, we presented a general simple microemulsion method to synthesize monodisperse organic–inorganic hybrid hollow mesoporous silica spheres (HMNs) with enlarged pore sizes by the co-condensation of TEOS and 1,2-bis(triethoxysilyl)ethane (BTEE). The whole process just involved acid-promoted pre-hydrolysis of TEOS and BTEE to obtain amphiphilic organosilanes to emulsify the oil droplets. Meanwhile, utilizing the composite micelles of CTAB and pore expanders such as the anion surfactant sodium salicylate (NaSaL), nonionic surfactants such as P123 and F127, hydrophobic oils such as cyclohexane (CyH) and 1,3,5-trimethyl benzene (TMB) to jointly construct a stable O/W microemulsion, a hollow structure could be directly obtained, which also exhibited an enlarged pore size. In addition, the diameters, shell thicknesses, and pore sizes (2.5–4.2 nm) could be controlled by adjusting the amounts of expanders. This general microemulsion method can also provide theoretical guidance for the synthesis of other hollow mesoporous spheres. [ABSTRACT FROM AUTHOR]

• Objective parameters of the AEPs were identified in rats treated with SS. • Reduced sensory input was shown by hearing thresholds and ABR peak I amplitudes. • Reduced latencies were found in the ABR (8-24kHz), MLR and LLR in SS-induced tinnitus. • Central gain was reflected by increased amplitudes in ABR, MLR, and LLR. • Behavioral tinnitus was correlated to peak IV of ABR, and P2 and N2 of LLR. Early-response auditory evoked potentials (AEPs) in humans are significantly altered in tinnitus. These changes are closely related to that seen in animals, leading to new approaches to study tinnitus based on objective parameters. The purpose of this study was to characterize the AEPs in animals with tinnitus, by assessing early to late latency responses. For behavioral evaluation, rats were trained using positive reinforcement to press a lever in the presence of an auditory stimulus and to not press during silence. The auditory brainstem response (ABR), middle latency response (MLR) and auditory late latency response (LLR) were correlated to the false-positive responses (pressing the lever during silence), after oral administrations of Sodium Salicylate (SS, 350 mg/kg). In the present study, SS significantly increased the hearing thresholds and reduced ABR peak I amplitudes across the frequency range (4–32 kHz). In contrast, increased amplitudes were observed for several peaks in ABR, MLR, and LLR. Moreover, reduced ABR latencies in response to 8, 16 and 24 kHz tone bursts were observed after SS administration. Similarly, the central evaluation also revealed significantly reduced latencies in MLR and LLR during SS administration. In contrast, increased latencies were observed for ABR latencies in response to 32 kHz tone bursts, and at the P1-N1 component of LLR. Correlational analysis revealed that latencies and amplitudes of peaks II and IV (8 and 16 kHz) of ABR, and N2 latency and P2-N2 amplitude of LLR were associated with behavioral tinnitus. We suggest that AEPs can be used in the rat to evaluate the reduced sensory input and the increased central gain in SS-induced tinnitus, as well as reduced latencies (8–16 kHz) to distinguish between hearing loss and tinnitus. [ABSTRACT FROM AUTHOR]

The effect of sodium salicylate (NaSal) on the spherical-to-threadlike micelle shape transition in 3-hexadecyloxy-2-hydroxy-propyl trimethyl ammonium bromide (R16HTAB) solution was studied using molecular dynamics simulation. The simulations were started from a preassembled infinitely long threadlike micelle of R16HTAB. By analyzing the aggregation morphologies and structural details, we find that the preassembled threadlike micelle in the absence of NaSal was unstable and assembled into a spherical micelle. While in the presence of NaSal, the threadlike micelle exhibited fluctuations but remained the threadlike shape during the long simulation run. The Sal− ions were found to penetrate inside the micelle, which promoted the junction between the surfactant and salicylate counterion. The aromatic Sal− ions located in the surfactant headgroup region with their phenyl groups pointing toward the interior core region of the micelle. From another simulation started with two individual spherical micelles, we found that the Sal− ions can link the two spherical micelles into a long threadlike micelle, in accordance with a mode proposed by experimental studies. Our studies showed that the H-bonds and electrostatic interactions between the Sal− ions and the surfactants played an important role in micellar growth and stabilising the threadlike micelle. [ABSTRACT FROM AUTHOR]

Rationale: Stressful life events are suggested to contribute to the development of various pathologies, such as cardiovascular disorders, whose etiopathogenesis is highly associated with elevated levels of serum amyloid A (SAA) proteins. SAA synthesis in the liver is regulated by a complex network of cytokines acting independently or in concert with various hormones/stimulants including the stress-activated sympathetic nervous system. Objective: This study aims to investigate the underlying mechanisms that regulate the stress-induced hepatic synthesis of SAA, with particular focus on adrenoceptors (AR), major components of the sympathoadrenal response to stress. Methods and results: We demonstrated that repeated stress elevates IL-1β, IL-6, and TNFα serum levels in mice, accompanied by increased synthesis and secretion of hepatic SAA1/2 and SAA3, an effect that was blocked by AR antagonists. Moreover, stimulation of α1- and β1/2-ARs mimics the stress effect on SAA1/2 regulation, whereas α2-AR stimulation exhibits a relatively weak impact on SAA. In support of the essential cytokine contribution in the AR-agonist induced SAA production is the fact that the anti-inflammatory drug, sodium salicylate, prevented the AR-stimulated hepatic SAA1/2 synthesis by reducing IL-1β levels, whereas IL-1β inhibition with Anakinra mimics this sodium salicylate preventive effect, thus indicating a crucial role for IL-1β. Interestingly, the AR-driven SAA3 synthesis was elevated by sodium salicylate in a TNFα-dependent way, supporting diverse and complex regulatory roles of cytokines in SAA production. In contrast to α1/α2-AR, the β1/2-AR-mediated SAA1/2 and SAA3 upregulation cannot be reversed by fenofibrate, a hypolipidemic drug with anti-inflammatory properties. Conclusion: Taken together, these findings strongly support a critical role of the AR-stimulated inflammatory response in the hepatic SAA production under stressful conditions, highlighting distinct AR type-specific mechanisms that regulate the hepatic synthesis of SAA1/2 and SAA3. [ABSTRACT FROM AUTHOR]

An investigation concerning Pelargonium graveolens plant was carried out during two successive growing seasons of (2013 and 2014) at the Experimental Farm, Faculty of Agriculture, Menoufia University, Shebin El - Kom, Egypt. This study was designed to determine the efficiency of antitranspirant agents I.e., magnesium carbonate (MgCO3) and sodium salicylate (S.S) at (10, 20 and 30 ppm) which used as chemical antitranspirant and active dry yeast (ADY) at (5, 10 and 15 g/l) which used as natural antitranspirant on growth, yield and active constituents of geranium plant (Pelargonium graveolens) grown on a clayey soil. Results reported that, all antitranspirant agents at different concentrations had a significant effects on growth and yield characters such as plant height (cm), number of main branches/plant, fresh weight of herb (g/plant) and fresh weight of leaves (g/plant and ton/fed) in the 1st and 2nd cuts during two seasons. Their maximum values in this concern were found in plants sprayed with active dry yeast (ADY) at 10 g/l in two cuts during both seasons. Also, the application of sodium salicylate at (20 and 30 ppm) produced the highest oil content (%) for the 1st and 2nd cuts, respectively during both seasons. Moreover, geraniol, linalool, gerannyl tiglate and cis-rose oxide were found to be the major compounds in the essential oil of Pelargonium graveolens which reached its maxima by spraying (ADY) at 10 mg/l,(ADY) at 15 mg/l, (S.S) at 20 ppm and (S.S) at 30 ppm, respectively during second cut in the first season. [ABSTRACT FROM AUTHOR]

• Explicit test of the central gain model of hyperacusis using a dual behavioral-electrophysiological approach. • Combined stable measure of loudness perception using auditory reaction time with chronic electrophysiological recordings. • Examined effect of salicylate on evoked-response in auditory cortex and inferior colliculus of behaviorally phenotyped rats. • Salicylate induced parallel changes to loudness and evoked responses consistent with temporary hearing loss and hyperacusis. • Behavioral and physiological changes were correlated within an animal, providing strong support for the central gain model. The central gain model of hyperacusis proposes that loss of auditory input can result in maladaptive neuronal gain increases in the central auditory system, leading to the over-amplification of sound-evoked activity and excessive loudness perception. Despite the attractiveness of this model, and supporting evidence for it, a critical test of the central gain theory requires that changes in sound-evoked activity be explicitly linked to perceptual alterations of loudness. Here we combined an operant conditioning task that uses a subject's reaction time to auditory stimuli to produce reliable measures of loudness growth with chronic electrophysiological recordings from the auditory cortex and inferior colliculus of awake, behaviorally-phenotyped animals. In this manner, we could directly correlate daily assessments of loudness perception with neurophysiological measures of sound encoding within the same animal. We validated this novel psychophysical-electrophysiological paradigm with a salicylate-induced model of hearing loss and hyperacusis, as high doses of sodium salicylate reliably induce temporary hearing loss, neural hyperactivity, and auditory perceptual disruptions like tinnitus and hyperacusis. Salicylate induced parallel changes to loudness growth and evoked response-intensity functions consistent with temporary hearing loss and hyperacusis. Most importantly, we found that salicylate-mediated changes in loudness growth and sound-evoked activity were correlated within individual animals. These results provide strong support for the central gain model of hyperacusis and demonstrate the utility of using an experimental design that allows for within-subject comparison of behavioral and electrophysiological measures, thereby making inter-subject variability a strength rather than a limitation. [ABSTRACT FROM AUTHOR]

• Stimulus-timing-dependent plasticity is altered in animals administered salicylate. • Cross-unit spontaneous synchrony and firing rates are increased in salicylate-induced tinnitus. • GPIAS and operant conditioning both indicate tinniutus in animals administered salicylate. • Salicylate-induced tinnitus and noise-exposure-induced tinnitus could have a similar mechanism. Following noise overexposure and tinnitus-induction, fusiform cells of the dorsal cochlear nucleus (DCN) show increased spontaneous firing rates (SFR), increased spontaneous synchrony and altered stimulus-timing-dependent plasticity (StDP), which correlate with behavioral measures of tinnitus. Sodium salicylate, the active ingredient in aspirin, which is commonly used to induce tinnitus, increases SFR and activates NMDA receptors in the ascending auditory pathway. NMDA receptor activation is required for StDP in many brain regions, including the DCN. Blocking NMDA receptors can alter StDP timing rules and decrease synchrony in DCN fusiform cells. Thus, systemic activation of NMDA receptors with sodium salicylate should elicit pathological changes to StDP, thereby increasing SFR and synchrony and induce tinnitus. Herein, we examined the action of salicylate in tinnitus generation in guinea pigs in vivo by measuring tinnitus using two behavioral measures and recording single-unit responses from DCN fusiform cells pre- and post-salicylate administration in the same animals. First, we show that animals administered salicylate show evidence of tinnitus using both behavioral paradigms, cross-validating the tests. Second, fusiform cells in animals with tinnitus showed increased SFR, synchrony and altered StDP timing rules, like animals with noise-induced tinnitus. These findings suggest that alterations to fusiform-cell plasticity are an essential component of tinnitus, regardless of induction technique. [ABSTRACT FROM AUTHOR]

Abstract An analysis on the diverse molecular interactions of implausible food preservatives, Sodium benzoate (SBz), Sodium salicylate (Scyt) in the aqueous solutions of Benzyltriethylammoniun chloride (BTEACl), Benzyltrimethylammoniun chloride (BTMACl) having durable anti-bacterial effect have been explored thoroughly by various physicochemical methodologies such as Density, Refractive index, Viscosity, Electrical conductivity, at five different temperatures ranging from 298.15 K to 318.15 K. Anti-bacterial as well as the anti-fungal effects of the ternary mixtures, (BTEACl + SBz + H 2 O), (BTEACl + Scyt + H 2 O), (BTMACl + SBz + H 2 O) and (BTMACl + Scyt + H 2 O) were further analysed for better results and found to act synergistically below the MIC of both the food preservative, thus minimises the hazardous threat, caused by unnecessarily excessive consumption of food preservatives. Association constants governed by diverse intermolecular interactions in the solution phase were studied by UV–vis spectroscopy. Construction of thermodynamic background caused by innumerable interactions taking place in the ternary mixtures was explored by calculating the free energies of various molecular associations. The genesis of diverse interactions was exposed by measurement of the apparent molar volume (ϕ v), limiting apparent molar volume (ϕ v 0), molar refraction (R M), limiting molar refraction (R M 0) viscosity B coefficients and reveals as strong solute-solvent interaction, over the solute-solute and solvent-solvent interactions. Optimum energies with the optimised geometries of molecular assembly for (BTEACl + SBz), (BTEACl + Scyt), (BTMACl + SBz) and (BTMACl + Scyt) systems were calculated from Ab-initio quantum chemical calculations using Gaussian 09W quantum chemical package which found supportive to the practical outcomes. Graphical abstract Unlabelled Image Highlights • Antimicrobial activity of FPs was studied with ILs revealing synergistic below reported MICs to kill micro-organisms. • The physico-chemical methodologies describe the mode of solute - solvent interactions between the FPs and ILs in solution. • Calculation of (δϕ E 0/ δT) P and (dB/dT) indicate structure making solute – solvent interaction. • Association constants, optimisation energy and ΔG for the molecular assembly grown in solution dictate their stability. • Synergistic combinations of FPs with ILs reduces the level of FPs: prevents spoilage of foods making world health, safe. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of a chemiluminescent metal–organic framework with high porosity is reported. It consists of Zr6O6(OH)4 nodes connected by 4,4′‐(anthracene‐9,10‐diyl)dibenzoate as the linker and luminophore. It shows the topology known for UiO‐66 and is therefore denoted PAP‐UiO. The MOF was not only obtained as bulk material but also as a thin film. Exposure of PAP‐UiO as bulk or film to a mixture of bis‐(2,4,6‐trichlorophenyl) oxalate, hydrogen peroxide, and sodium salicylate in a mixture of dimethyl and dibutyl phthalate evoked strong and long lasting chemiluminescence of the PAP‐UiO crystals. Time dependent fluorescence spectroscopy on bulk PAP‐UiO and, for comparison, on dimethyl 4,4′‐(anthracene‐9,10‐diyl)dibenzoate provided evidence that the chemiluminescence originates from luminophores being part of the PAP‐UiO, including the luminophores inside the crystals. [ABSTRACT FROM AUTHOR]

Sodium salicylate (SS) is one of the nonsteroidal anti-inflammatory drugs and widely used in clinical practice. Therefore, we aimed to investigate the potential ototoxicity mechanism of sodium salicylate: the influence of Ca2+/calmodulin-dependent protein kinase II (Ca2+/CaMKII) in interaction between NMDA receptors (NMDAR) and GABAA receptors (GABAAR) in rat cochlear spiral ganglion neurons (SGNs). After treatment with SS, NMDA, and an NMDAR inhibitor (APV), the changes of GABAAR β3 (GABR β3) mRNA, surface and total protein, and GABAAR currents in SGNs were assessed by quantitative PCR, Western blot, and whole-cell patch clamp. Mechanistically, SS and/or NMDA increased the GABR β3 mRNA expression, while decreased GABR β3 surface protein levels and GABAAR-mediated currents. Moreover, application of SS and/or NMDA showed promotion in phosphorylation levels at S383 of GABR β3. Collectively, Ca2+ chelator (BAPTA) or Ca2+/CaMKII inhibitor (KN-93) reversed the effects of SS and/or NMDA on GABAAR. Therefore, we hypothesize that the interaction between NMDAR and GABAAR is involved in the SGNs damage induced by SS. In addition, the underlying molecular mechanism is related to Ca2+/CaMKII-mediated signaling pathway, which suggests that the interaction between calcium signal-regulated receptors mediates SS ototoxicity. [ABSTRACT FROM AUTHOR]

Objective: High doses of sodium salicylate (SS) are known to induce tinnitus, general hyperexcitability in the central auditory system, and to cause mild hearing loss. We used the auditory brainstem response (ABR) to assess the effects of SS on auditory sensitivity and temporal processing in the auditory nerve and brainstem. ABRs were evoked using tone burst stimuli varying in frequency and intensity with presentation rates from 11/s to 81/s. Design: ABRs were recorded and analysed prior to and after SS treatment in each animal, and peak 1 and peak 4 amplitudes and latencies were determined along with minimal response threshold. Study Sample: Nine young adult CBA/CaJ mice were used in a longitudinal within-subject design. Results: No measurable effects of presentation rate were found on ABR threshold prior to SS; however, following SS administration increasing stimulus rates lowered ABR thresholds by as much as 10 dB and compressed the peak amplitude by intensity level functions. Conclusions: These results suggest that SS alters temporal integration and compressive nonlinearity, and that varying the stimulus rate of the ABR may prove to be a useful diagnostic tool in the study of hearing disorders that involve hyperexcitability. [ABSTRACT FROM AUTHOR]

Low-grade inflammation has been implicated as a contributor to metabolic disease during the transition to lactation. In previous work, administration of sodium salicylate (SS) for 7 d led to hypoglycemia in mature dairy cows in early lactation. The purpose of this study was to identify the mode of action underlying this response to SS. Twenty mature (parity 3) cows were assigned alternately at time of calving to either control or SS treatments; the control received a molasses placebo in drinking water, whereas SS received 2.3 g/L of SS with the molasses carrier in drinking water for 7 d after parturition. Blood samples were collected daily. A glucose turnover assay was performed on d 7, followed by liver, muscle, and adipose tissue biopsies. There were no treatment effects on intake of dry matter or water. Tumor necrosis factor α mRNA abundance tended to be decreased by SS in adipose tissue but not in muscle or liver, and plasma haptoglobin and adiponectin concentrations were not altered by treatment. Treatment did not significantly alter plasma glucose or insulin concentrations, but plasma glucagon concentration tended to be increased by SS and the insulin: glucagon molar ratio was significantly decreased. Cows on SS had a tendency for a 25% decrease in glucose turnover rate compared with control cows. However, there were no differences in transcript abundance of pyruvate carboxylase (PC) or glucose-6-phosphatase (G6PC) in liver or of glucose transporter 4 (GLUT4) in any of the tissues. Finally, SS did not alter insulin receptor substrate-1 phosphorylation in muscle or adipose, but tended to increase phosphorylation of AMPactivated protein kinase and decrease protein kinase B phosphorylation in adipose tissue. These findings may be explained by enhanced hepatic insulin sensitivity leading to posttranscriptional suppression of gluconeogenesis and adaptive responses to decreased glucose supply in the pancreas and adipose tissue. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we report the rheological properties of the photorheological fluid by using steady state test and frequency sweep measurement. The fluids are consisted of the cationic surfactant (3-hexadecyl-2-hydroxypropyltrimethylammonium bromide, R 16 HTAB), sodium salicylate (NaSal) and commonly photosensitive aromatic compound (sodium trans - ortho -methoxycinnamic acid, trans -NaOMCA). Initially, systems of R 16 HTAB/ trans -NaOMCA and R 16 HTAB/NaSal in basic solution are able to self-assemble into long wormlike micelles, inspiring a high viscoelasticity of the sample. After adding NaSal (or NaOMCA) to the R 16 HTAB/NaOMCA (or R 16 HTAB/NaSal) aqueous solution, the viscosity of the mixed solution was reduced. All systems containing NaOMCA show photoresponsive character. Under ultraviolet light, OMCA undergoes a photoisomerization from trans form to cis form, which changes the molecular packing at the micellar interface, shortens the length of the wormlike micelles to decrease the viscosity of the systems. Highlights • A simple photorheological fluid was investigated by rheological method, Cryo-TEM, NMR. • The effect NaSal on the photorheological system was compared. • The viscosity of R 16 HTAB/NaOMCA and R 16 HTAB/NaOMCA/NaSal system both reduced after UV irradiation. [ABSTRACT FROM AUTHOR]

The terahertz spectra of salicylic acid and sodium salicylate are measured by broadband terahertz time-domain spectroscopy (THz-TDS). Two absorption features of salicylic acid and three characteristic features of sodium salicylate are reported for the first time. Our investigation shows that salicylic acid and sodium salicylate can be easily distinguished based on their distinctive THz spectra, which could be attributed to their intra- and intermolecular structure differences. Furthermore, solid-state density functional theory calculations reveal that the absorption features of salicylic acid mainly originate from intermolecular interactions, except for the absorption feature at 2.28 THz, while gaseous-state theory calculations show that the absorption features of sodium salicylate mainly come from intramolecular vibrations except for the absorption feature at 0.40 THz. Our investigation indicates that THz vibrational modes are highly sensitive to molecular structures and intermolecular interactions, promoting the application of THz spectroscopy in distinguishing chemicals and pharmaceuticals with similar molecular structures. [ABSTRACT FROM AUTHOR]

Highlights • Complex local flow around a tiny bubble surface under pressure-oscillating field. • 2D flow birefringence profile captured by the latest high-speed polarization camera. • A negative wake generated cyclically at the tail of bubble due to rapid deformation. Abstract The motion of a tiny air bubble in an aqueous solution of cetyl trimethyl ammonium bromide and sodium salicylate (CTAB/NaSal), which forms wormlike micelles, was observed using a high-speed polarization camera. Complex local flow is observed around the bubble surface because the bubble shape deforms repeatedly at 100 Hz. The camera can be used to measure the retardation distribution, which is related to the stress field around the bubble. Different retardation and orientation angle distributions were observed during the contraction and expansion phases. In the contraction phase, a strong retardation distribution appears at the tail of the cusped bubble. The occurrence of uniaxial elongation deformation is considered to be due to the negative wake because they are closely correlated. In contrast, a weak retardation distribution spreads at the upper side of the bubble during the expansion phase, where biaxial extensional deformation occurs due to expansion of the bubble surface. These significant changes in strong elastic stress distributions, which correspond to the orientation angle profiles, can result in increase of bubble rising velocities. [ABSTRACT FROM AUTHOR]

We report experiments on two series of wormlike micellar solutions that comprise octyl trimethylammonium bromide/sodium oleate (OTAB/NaOA) and cetylpyridinium chloride/sodium salicylate (CPCl/NaSal) using a capillary breakup extensional rheometer (CaBER) and a dripping onto substrate (DoS) technique. These wormlike micellar systems show a peak in zero shear viscosity or in the shear relaxation time beyond a critical surfactant or salt concentration. Prior cryogenic transmission electron microscopy imaging has indicated that the system based on OTAB/NaOA experiences a transition from linear to shorter linear micelles (L-L) beyond the viscosity peak. However, the linear wormlike micelles based on CPCl/NaSal form branched networks beyond the viscosity peak (L-B). In this work, we investigate whether the extensional rheology is sensitive to these two different microstructural transitions. In particular, we attempt to develop a criterion based on the extensional flow parameters in order to distinguish these two systems from each other. In addition, we probe the possibility of flow-induced micellar breakage imposed by capillary breakup extensional experiments. Our results indicate that at a given zero shear viscosity, the branched wormlike micelles based on CPCl/NaSal exhibit a longer filament lifetime tfil than the linear wormlike micelles. However, beyond the critical concentration, the linear wormlike micelles based on OTAB/NaOA exhibit significantly shorter filament lifetimes than their linear counterparts at concentrations below the viscosity peak. More importantly, we show that the filament lifetime scales differently with zero shear viscosity η0 in these two systems. For L-B transition, t fil ∝ η 0 1.1 below the viscosity peak and t fil ∝ η 0 0.76 above the viscosity peak. However, for L-L transition, this scaling remains the same for concentrations below and above the viscosity peak and reads as t fil ∝ η 0 0.5 . These findings provide a novel criterion to distinguish these two types of microstructural transitions in wormlike micelles. On the other hand, we demonstrate that the Trouton ratio, filament lifetime, and the extensional relaxation time measured by CaBER technique are all lower than the ones obtained by DoS method. The latter result provides the first evidence for strong nonlinear effects (e.g., flow-induced micellar breakage) in capillary breakup extensional flows of wormlike micelles. [ABSTRACT FROM AUTHOR]

We developed injectable hydrogels for the slow release of analgesic drugs in birds as an in vivo model of pharmacokinetics in wild avian species. Hydrogels loaded with sodium salicylate (NaSA) were injected subcutaneously in Ross broiler chickens. The hydrogels were made by dissolving sodium alginate and NaSA in water at 2 different concentrations (low, LALG,high, HALG) and then adding calcium chloride. In vitro drug release studies were performed by swelling the hydrogels in water and analyzing serial samples by ultraviolet-visible (UV-Vis) spectroscopy. Dried hydrogel films of the same formulations of the two alginate concentrations then were dissolved in sterile water for the in vivo pharmacokinetic study conducted in 18 chickens divided into 3 groups of 6 birds. Each of the 2 resultant NaSA hydrogel solutions were filtered with 0.2-lm syringe filters before injecting at a NaSA dose of 150 mg/kg SC in the respective LALG or HALG groups. The control group was injected SC with the same dose of NaSA dissolved in water. Pharmacokinetics parameters calculated by the compartmental and noncompartmental approaches were compared among the 3 groups by the Kruskal-Wallis test. Results of in vitro studies showed that both hydrogels released 80% of the drug during the first 3.5 hours. Results of the pharmacokinetic study indicated that NaSA concentrations remained above the minimum effective concentration (MEC) for analgesia in humans for 24 6 8.9 (LALG) to 26 6 4 (HALG) hours for the hydrogel formulations compared to 10 6 5.6 hours for the aqueous formulation. These hydrogel formulations may have potential in providing long-term analgesia in avian species, but need further evaluation with pharmacodynamic or pharmacokinetic/ pharmacodynamic modeling studies. [ABSTRACT FROM AUTHOR]

Abstract Three types of ionically crosslinked (with citric acid) chitosan discs were loaded with the highly water- soluble drug, sodium salicylate (SS) and the poorly water-soluble drug, indomethacin (Ind). In separate experiments the hydrated discs were immersed in a de-crosslinking solution comprising of different concentrations of calcium chloride, which induced a controlled erosion of the discs, a process which was optimized to synchronize the release rates of the two drugs over a predetermined period of time. The optimization was accomplished by manipulating six factors: chitosan MW, its amount in the formulation, the concentration of the crosslinker agent, the concentration of the de-crosslinking agent in the dissolution medium, its pH and its temperature. A computerized multifactorial definitive screening design analysis assisted in minimizing the number of experiments. The quotient of the SS to Ind release rates, the difference factor f1, the similarity factor f2 and the combination of f1 and f2 were determined as the experimental responses. The computerized prediction profilers that were used to simulate the contribution of the experimental factors and their effect on the experimental responses led to a successful erodible formulation with a concomitant release of the two drugs over 150 min. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract In this work, the potentiostatic electropolymerization of polypyrrole (PPy) on iron in aqueous solution of sodium salicylate and pyrrole is studied in situ by odd random phase electrochemical impedance spectroscopy (ORP-EIS). The influence of the pyrrole concentration on the electrosynthesis process is investigated. The ORP-EIS technique ensures a reliable analysis of the PPy electrosynthesis on iron by means of an advanced data analysis of the non-linear and non-stationary behaviour and the signal-to-noise ratio of the system. Additionally, the structure and the chemical nature of the PPy film on iron are studied by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and glow discharge optical emission spectroscopy (GDOES). The results of the characterization confirm the presence of the passivation layer at the PPy/iron interface formed prior to the polymer deposition. The modelling of the impedance evolution over time provides the quantitative analysis of the electropolymerization of PPy on iron. The results show that the electrosynthesis of pyrrole on oxidizable iron in the presence of sodium salicylate is a complex process, which includes not only the pyrrole oxidation reactions but also reactions such as the oxidation/reduction of the iron surface and/or reactions between the iron, formed interlayer and polypyrrole. Highlights • The electropolymerization of PPy on iron is studied in-situ by odd random phase EIS. • The influence of the pyrrole concentration on the synthesis process is investigated. • The PPy/Fe is additionally analysed with SEM, EDX and GDOES. • The modelling of the EIS provides the quantitative analysis of the synthesis of PPy. • Electropolymerization of PPy on oxidizable metal includes at least two processes. [ABSTRACT FROM AUTHOR]

Sodium salicylate (2‐hydroxybenzoate) has been fully characterised by single‐crystal X‐ray diffraction (SCXRD), thermogravimetric analysis in combination with in operando FTIR spectroscopy and GC‐MS, as well as by UV/Vis absorption and photoluminescence spectroscopy backed up by DFT calculations. SCXRD revealed a layered crystal structure composed of ionic sheets formed by Na+–O contacts sandwiched between π‐stacked aromatic rings of the salicylate anion oriented perpendicular to the layer plane. Only weak van der Waals interactions hold the individual sheets together. No solid/solid or solid/liquid phase transitions were observed upon heating, but a three‐step decomposition was observed, with the first onset at 245 °C corresponding to concomitant release of CO2 and phenol. The UV/Vis absorption spectra show temperature‐dependent absorption bands at around 305 and/or 345 nm, which according to DFT calculations correspond to the absorption of the carboxylate or phenolate proton transfer species, respectively. In solution, indications of the phenolate species are found only in a very apolar solvent (cyclohexane). Because of excited‐state relaxation, emission always occurs from the phenolate structure, which explains the large Stokes shift. Piling on the layers: Sodium salicylate has been for the first time fully characterised by single‐crystal XRD, TGA in combination with in operando FTIR spectroscopy and GC‐MS, as well as by UV/Vis and photoluminescence spectroscopy backed up by DFT calculations. Its layered crystal structure is made up of ionic Na–O sheets sandwiched between π‐stacked aromatic rings oriented perpendicular to the layer plane (see figure). Proton transfer within the ionic layers is identified as the reason for the particular luminescence behaviour. [ABSTRACT FROM AUTHOR]

Abstract In this study, the self-assembly of cationic surfactant cetyltrimethyl ammonium chloride (CTAC) and nonionic polymer polyacrylamide (PAM) in aqueous solution with added sodium salicylate (NaSal) as counter-ion salt is studied using a coarse-grained molecular dynamic simulation (CGMD). The microstructure evolution shows that in the mixed solutions, surfactant micelles are readily to associate with polymer and can form a new complex of CTAC and PAM with interconnected network structures, which can be attributed to the hydrophobic interactions, the attraction between acylamino and the head of CTAC, and the attraction between Sal− and acylamino. The calculation of radial distribution function for different sites also proved the aggregate of the surfactant and polymer. Then a reverse non-equilibrium molecular dynamics (RNEMD) simulation is used to investigate the rheological property of the mixed solutions, the CTAC/NaSal solution and the PAM solution. The molecular dynamics simulation demonstrates that the viscosity of the CTAC/PAM/NaSal solution is significantly higher than that of the CTAC/NaSal solution, mainly because the surfactant micelles interacted with the polymer and formed rod-like micelles. Highlights • MARTINI force field CGMD simulation is used to study the self-assembly of PAM and CTAC. • The effect of NaSal on the association of PAM with CTAC is investigated. • Surfactant-polymer complex interconnected network structures formed in simulation. • Network structures and viscosity of CTAC/PAM/NaSal is discussed. [ABSTRACT FROM AUTHOR]

The influence of sodium salicylate (NaSal) concentration on the linear micelle formation in an aqueous solution of cetyltrimethylammonium bromide (CTAB) is investigated by the frequency-domain electric birefringence relaxation spectroscopy (FEB method). The contour length L of linear micelles is found to increase with increasing NaSal concentration Cs but for further increase of Cs in excess of the CTAB concentration, L decreases, i.e., linear micelles break into shorter pieces. The FEB result indicates also that the diffusion constant of salicylate ions bound to a linear micelle is nearly independent of Cs with an average value smaller than that of free salicylate ions. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

• Cloudy behavior of the TX-100 + ciprofloxacin hydrochloride (CFH) mixture has been conducted. • CP of TX-100 + CFH mixture follow the order: C P (a q. 4 - A B A) < C P a q. C A F ≈ C P a q. P E G < C P a q. N a B e n z < C P a q. N a S a l. • Clouding of TX-100 + CFH mixture was a nonspontaneous process. • Enthalpy (Δ H c 0) and entropy (Δ S c 0) of clouding were obtained positive in HDTs media. • Compensation temperature (T c)/intrinsic enthalpy gain (Δ H c 0 , ∗) were calculated and discussed. In the present study, the cloudy development of nonionic triton X-100 (TX-100) and an antibiotic drug ciprofloxacin hydrochloride (CFH) mixture has been conducted by applying the cloud point (CP) measurements method. The CP of TX-100 + CFH mixture was examined in aqueous solutions of hydrotropes (HDTs) (sodium benzoate (NaBenz), sodium salicylate (NaSal), 4-amino benzoic (4-ABA), polyethylene glycol (PGE) and Caffeine (CAF)). The TX-100 and CFH concentration were conserved constant at 50 and 1 mmol kg−1 correspondingly throughout the investigation. The CP values of TX-100 + CFH solution were augmented in the existence of NaBenz, NaSal, CAF along with PEG but diminished in aq. 4-ABA solution; the effects were obtained to be augmented with the enhancing hydrotropes contents. The CP values for TX-100 + CFH mixture in aq. hydrotropes media follow the pattern: C P (a q. 4 - A B A) < C P a q. C A F ≈ C P a q. P E G < C P a q. N a B e n z < C P a q. N a S a l . Therefore, the solubility of TX-100 + CFH mixture is achieved to be decreased in aq. solutions of 4-ABA while the solubility experienced an enhancement in aq. NaSal, NaBenz, PEG and CAF solutions. Among hydrotropes used in the present study, NaSal is the most effective solubility enhancer. The free energy (Δ G c 0) were achieved to be positive in all the solvent media used in the study which exposes that the cloudy development process isnot spontaneous. The enthalpy (Δ H c 0) and the entropy (Δ S c 0) of clouding were obtained to be positive in hydrotropes media. The Δ H c 0 and Δ S c 0 values imply that the main forces of the cloudy formation in TX-100 and CFH system are hydrophobic interaction, hydrogen bonding, and electrostatic interactions. The compensation temperature (T c) along with the intrinsic enthalpy gain (Δ H c 0 , ∗) were also calculated and discussed. It is probable that the knowledge gained from these types of studies will be quite helpful in both pharmaceutics formulations and drug delivery system. [ABSTRACT FROM AUTHOR]