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This study examined the controlled release of cetylpyridinium chloride (CPC) from a tissue conditioner (TC) containing CPC-montmorillonite (CPC-Mont), the associated antimicrobial activity, and oral mucosa irritation. The CPC release test was performed daily for 28 days in three test solutions: distilled water, 0.2 M NaCl, and 0.2 M HCl. The antimicrobial activities for 7, 14, 21, and 28 days against Candida albicans, Staphylococcus aureus, and Streptococcus mutans were assessed according to the JIS Z 2801/ISO 22196 standard. An oral mucosa irritation test was conducted using cheek pouches in five male hamsters according to the ISO 10993-10:2010 standard. The amount of CPC released each day and the cumulative amount released over 28 days (6.12 mg) were less than the daily safe maximum of sore throat medicines (8 mg). Additionally, TC with CPC-Mont could sustain antimicrobial activity against adherent bacteria for 14 days and has no oral mucosa irritation potential. [ABSTRACT FROM AUTHOR]

Long-term anti-bacterial effect is a desired ability of any dental material in combating tooth caries as one of the most common and widespread persistent diseases today. Among several cationic quaternary ammonium compounds with antiseptic properties, cetylpyridinium chloride (CPC) is often used in mouthrinses and toothpastes. In this study, we incorporated CPC in a soft phyllosilicate mineral (clay), referred to as montmorillonite (Mont), to enable gradual CPC release with rechargeability. Besides measuring CPC release and recharge, we examined the anti-bacterial effect, cytotoxicity and bonding effectiveness of five experimental adhesive formulations, prepared by adding 1 and 3 wt% CPC_Mont, 3 wt% Mont (without CPC), and 1 and 3 wt% CPC (without Mont) to the commercial adhesive Clearfil S3 Bond ND Quick ('C-S3B'; Kuraray Noritake). Strong inhibition of Streptococcus mutans biofilm formation by CPC_Mont adhesives was confirmed by optical density and SEM. CPC release from CPC_Mont adhesives was higher and lasted longer than from CPC adhesives, while CPC_Mont adhesives could also be recharged with CPC upon immersion in 2 wt% CPC. In conclusion, CPC_Mont technology rendered adhesives anti-bacterial properties with recharge ability, this without reducing its bonding potential, neither increasing its cytotoxicity. Dental caries is one of the most prevalent chronic diseases in the population worldwide and is the major cause of tooth loss. In this study, we developed cetylpyridinium chloride (CPC) loaded montmorillonite (CPC-Mont) with a long-term antibacterial efficacy to prevent caries. CPC is an antibacterial agent approved by FDA, used as an OTC drug and contained in oral hygiene aids. CPC-Mont was incorporated in a dental adhesive to gradually release CPC. CPC_Mont technology rendered adhesives anti-bacterial properties with rechargeability, this without reducing its bonding potential, neither increasing its cytotoxicity. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Highlights • CPC interacts with and induces conformational change in Cp149 dimer. • CPC inhibits formation of HBV capsid structures. • CPC represses HBV biogenesis through inhibition of HBV capsid assembly. Abstract Hepatitis B virus (HBV) infection is a major risk factor for chronic liver disease, cirrhosis, and hepatocellular carcinoma (HCC) worldwide. While multiple hepatitis B drugs have been developed, build up of drug resistance during treatment or weak efficacies observed in some cases have limited their application. Therefore, there is an urgent need to develop substitutional pharmacological agents for HBV-infected individuals. Here, we identified cetylpyridinium chloride (CPC) as a novel inhibitor of HBV. Using computational docking of CPC to core protein, microscale thermophoresis analysis of CPC binding to viral nucleocapsids, and in vitro nucleocapsid formation assays, we found that CPC interacts with dimeric viral nucleocapsid protein (known as core protein or HBcAg) specifically. Compared with other HBV inhibitors, such as benzenesulfonamide (BS) and sulfanilamide (SA), CPC achieved significantly better reduction of HBV particle number in HepG2.2.15 cell line, a derivative of human HCC cells that stably expresses HBV. CPC also inhibited HBV replication in mouse hydrodynamic model system. Taken together, our results show that CPC inhibits capsid assembly and leads to reduced HBV biogenesis. Thus, CPC is an effective pharmacological agent that can reduce HBV particles. [ABSTRACT FROM AUTHOR]

Herein, we have investigated the interaction between three different amino acids (AA) namely glycine (Gly), threonine (Thr), and alanine (Ala) with cationic surfactant cetylpyridinium chloride (CPC) by conductance measurements and computational method. For pure CPC as well as amino acid–CPC mixtures, three different critical micelle concentrations (c*) were achieved. The values ofc* for the AA–CPC mixtures in KCl solution are lesser in comparison to the aqueous solution. The negative values ofare obtained in every studied system. The values ofandfor AA–CPC micellization reveal that both hydrophobic and hydrophilic interactions are the binding forces among CPC molecules and between AA and CPC. Molecular dynamics simulation indicates that the pyridine ring of CPC promotes the non-bonding interaction in AA–CPC complexes. Further quantum calculation revealed that non-conventional CH⋯O hydrogen bonding plays a critical role and stabilizes these complexes. [ABSTRACT FROM PUBLISHER]

Highlights: [•] A novel method of determination of DNA was proposed. [•] The linear range was 0.024–3.48μgmL−1. [•] The detection limit was 1.49ngmL−1. [ABSTRACT FROM AUTHOR]

Highlights: [•] Expression of full-length KIAA1199 is essential for HA depolymerizing activity. [•] The cleavage of N-terminal 30 amino acids occurs in functionally matured KIAA1199. [•] The deletion of the N-terminal portion results in altered localization of KIAA1199. [•] The N-terminal 30 amino acids of KIAA1199 are indeed the cleavable signal sequence. [Copyright &y& Elsevier]

Abstract: Recently, we have disclosed that human KIAA1199 (hKIAA1199) is a hyaluronan (HA) binding protein implicated in HA depolymerization. Although a murine homologue (mKiaa1199) was previously cloned, no information about the function of the molecule was available. Here, we show that cells transfected with mKiaa1199 cDNA selectively catabolized HA via the clathrin-coated pit pathway. A glycosaminoglycan-binding assay demonstrated the specific binding of mKiaa1199 to HA. These results were similar to our observations with hKIAA1199, although slight differences were found in the peak sizes of the minimum degradates of HA. We conclude that like hKIAA1199, mKiaa1199 is a hyaladherin, leading to HA depolymerization. [Copyright &y& Elsevier]

Abstract: The current study investigated the mixing behavior of surfactant–enzyme using spectroscopy, hydrodynamic and network modeling techniques. The model fluctuating enzyme by dodecyl trimethylammonium bromide (DTAB) was more efficient, as implied by the behavior of other methods. The results of the study were consistent with a distributed enthalpy and rate constants of the reactions may eventually be modulated by the conformational fluctuations. The underlying distribution of rate constants can be reconstructed from a set of reactions in which the kinetics at high viscosity. Based on the Hill kinetic, the novel species–reaction (SR) graph for perfect adaptation of the complex was predicted. These observations suggest that networks are ‘close to – monotone’, a characteristic that could contribute to the dynamic stability observed in complex behavior. The prediction accuracy of most models seems to be rather close to the performance of the experimental measurements. [Copyright &y& Elsevier]

Abstract: Objectives: Traumatic pulp exposure can bring about some permanent damages to tooth tissues including dental pulps. This study was designed to evaluate the effects of traumatic pulp exposure on the osteo/odontogenic capacity of dental pulp stem cells (DPSCs). Methods: Rat incisors were artificially fractured and dental pulps were exposed to the oral environment for 48h. Then, multi-colony-derived DPSCs from the injured pulps (iDPSCs) were isolated. Their osteo/odontogenic differentiation and the involvement of NF-κB pathway were subsequently investigated. Results: iDPSCs presented a lower proliferative capacity than normal DPSCs (nDPSCs), as indicated by MTT and FCM assay. ALP levels in iDPSCs were significantly higher (P <0.01) than those in nDPSCs. Alizarin red staining revealed that iDPSCs exhibited an increased capacity of calcium deposition. Moreover, iDPSCs expressed stronger osteogenic markers (Runx2/RUNX2 and Ocn/OCN) and less odontogenic gene/protein (Dspp/DSP) than nDPSCs in vitro. In vivo transplantation showed that nDPSCs implants generated the typical dentine-pulp complex while all iDPSCs pellets formed the osteodentin-like tissues which were immunopositive for OCN. Mechanistically, iDPSCs expressed the higher levels of cytoplasmic phosphorylated IκBα/P65 and nuclear P65 than nDPSCs, indicating an active cellular NF-κB pathway in iDPSCs. After the inhibition of NF-κB pathway, the osteogenic potential in iDPSCs was significantly down-regulated while odontogenic differentiation was up-regulated, as indicated by the decreased Alp/Runx2/Ocn and uprised Dspp expression. Conclusions: Pulp exposure for 48h decreased the odontogenic capacity and enhanced the osteogenic potential of DPSCs via the NF-κB signalling pathway. [Copyright &y& Elsevier]

Abstract: Mucopolysaccharidoses (MPS) are caused by deficiency of lysosomal enzyme activities needed to degrade glycosaminoglycans (GAGs), which are long unbranched polysaccharides consisting of repeating disaccharides. GAGs include: chondroitin sulfate (CS), dermatan sulfate (DS), heparan sulfate (HS), keratan sulfate (KS), and hyaluronan. Their catabolism may be blocked singly or in combination depending on the specific enzyme deficiency. There are 11 known enzyme deficiencies, resulting in seven distinct forms of MPS with a collective incidence of higher than 1 in 25,000 live births. Accumulation of undegraded metabolites in lysosomes gives rise to distinct clinical syndromes. Generally, the clinical conditions progress if untreated, leading to developmental delay, systemic skeletal deformities, and early death. MPS disorders are potentially treatable with enzyme replacement therapy or hematopoietic stem cell transplantation. For maximum benefit of available therapies, early detection and intervention are critical. We recently developed a novel high-throughput multiplex method to assay DS, HS, and KS simultaneously in blood samples by using high performance liquid chromatography/tandem mass spectrometry for MPS. The overall performance metrics of HS and DS values on MPS I, II, and VII patients vs. healthy controls at newborns were as follows using a given set of cut-off values: sensitivity, 100%; specificity, 98.5–99.4%; positive predictive value, 54.5–75%; false positive rate, 0.62–1.54%; and false negative rate, 0%. These findings show that the combined measurements of these three GAGs are sensitive and specific for detecting all types of MPS with acceptable false negative/positive rates. In addition, this method will also be used for monitoring therapeutic efficacy. We review the history of GAG assay and application to diagnosis for MPS. [Copyright &y& Elsevier]

Cetylpyridinium chloride (CPC) was evaluated as an antimicrobial against Listeria monocytogenes (LM) and Listeria innocua (LI) on fish. LI and LM showed the same reduction profile and the same minimum inhibitory and bactericidal concentrations. When CPC was applied to a diced fish matrix, reductions of 3.17-3.26 and 3.07-3.19 log were determined for LI and LM, respectively. Antimicrobial activity of CPC against LI resulted in initial reductions of 2.8-3.1 log in fresh fish fillets, 0.9-1.1 log in smoked fish fillets, and 3.2-3.4 log on fish skin. Effectiveness of CPC against total plate counts on fish skin showed reductions of 2.4-2.9 log. [ABSTRACT FROM AUTHOR]

The article presents a study that examines the genetic and cellular toxicity of antiseptic mouthwashes such as Cepacol, Periograd and Plax. It is noted that the researchers evaluated the genotoxicity of antiseptics using the Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster. The genotoxicity of the antiseptic mouthwashes was assessed through the responses in both the marker-heterozygous and balancer-heterozygous genotypes in the standard cross or high bio-activation crosses. In conclusion, the mitotic recombination increments in somatic cells of Drosophila melanogaster is due to ethanol metabolite.

Objective: To compare the effects of an experimental mouth rinse containing 0.07% cetylpyridinium chloride (CPC) (Crest Pro-Health®) with those provided by a commercially available mouth rinse containing essential oils (EOs) (Listerine®) on dental plaque accumulation and prevention of gingivitis in an unsupervised 6-month randomized clinical trial. Material and Methods: This double-blind, 6-month, parallel group, positively controlled study involved 151 subjects balanced and randomly assigned to either positive control (EO) or experimental (CPC) mouth rinse treatment groups. At baseline, subjects received a dental prophylaxis procedure and began unsupervised rinsing twice a day with 20 ml of their assigned mouthwash for 30 s after brushing their teeth for 1 min. Subjects were assessed for gingivitis and gingival bleeding by the Gingival index (GI) of Löe & Silness (1963) and plaque by the Silness & Löe (1964) Plaque index at baseline and after 3 and 6 months of rinsing. At 3 and 6 months, oral soft tissue health was assessed. Microbiological samples were also taken for community profiling by the DNA checkerboard method. Results: Results show that after 3 and 6 months of rinsing, there were no significant differences ( p=0.05) between the experimental (CPC) and the positive control mouth rinse treatment groups for overall gingivitis status, gingival bleeding, and plaque accumulation. At 6 months, the covariant (baseline) adjusted mean GI and bleeding sites percentages for the CPC and the EO rinses were 0.52 and 0.53 and 8.7 and 9.3, respectively. Both mouth rinses were well tolerated by the subjects. Microbiological community profiles were similar for the two treatment groups. Statistically, a significant greater reduction in bleeding sites was observed for the CPC rinse versus the EO rinse. Conclusion: The essential findings of this study indicated that there was no statistically significant difference in the anti-plaque and anti-gingivitis benefits between the experimental CPC mouth rinse and the positive control EO mouth rinse over a 6-month period. [ABSTRACT FROM AUTHOR]

Objective: After myocardial infarction, angiotensin II (AngII) promotes ventricular remodeling and deposition of extracellular matrix (ECM), e.g., collagen type 1 and 3. Whether AngII regulates the expression of small leucine-rich proteoglycans (SLRP) which are important modulators of collagen fibrillogenesis and are induced after experimental myocardial infarction in rats is not known. The aim of the present study was therefore to analyse in cultured cardiac fibroblasts the expression and secretion of the SLRP biglycan in response to AngII. Methods: Cardiac fibroblasts were isolated from neonatal Wistar Kyoto rats and used in the first passage. Expression of AT1- and AT2-receptors was verified by RT-PCR. Expression of protoeglycans was analyzed after metabolic labeling with [35S]-sulfate, by SDS-PAGE and Western analysis. In addition, mRNA expression was examined by means of RT-PCR and Northern analysis. The activity of the biglycan promoter was analyzed using three biglycan promoter–luciferase fusion constructs. Results: Biglycan was found to be the predominant proteoglycan produced by neonatal cardiac fibroblasts in vitro. In response to AngII (10−7 M), secretion of total [35S]-labeled proteoglycans and mRNA of biglycan were increased to 116±1.8% and 121±11% (n=5, mean±S.E.M.) of unstimulated controls, respectively. Biglycan induction in response to AngII was sensitive to Losartan (10−5 M) and unaffected by PD123177 (10−6 M), suggesting that the AT1-receptor mediates the induction of biglycan. Direct activation of the biglycan promoter downstream of the AT1-receptor was excluded by promoter activity assays. Instead, increased release of transforming growth factor beta 1 (TGFβ1) was detected by ELISA in response to AT1-receptor stimulation. Furthermore, neutralising antibodies to TGFβ1 inhibited biglycan induction in response to AngII. Conclusion: The results indicate that in cardiac fibroblasts AngII via the AT1-receptor causes autocrine release of TGFβ1, which in turn induces biglycan expression and secretion. [Copyright &y& Elsevier]

The influence on electrical resistance and membrane potential of rabbit corneas in vitro of some chemicals used as adjuvants in ophthalmic formulations was investigated, in the attempt to correlate changes in electrophysiological properties of the corneal tissue (possibly indicative of toxic/damaging effects to the corneal epithelium), with the promoting effect of the substances on transcorneal permeation in vitro of timolol maleate (TM). The chemicals, tested at different concentrations, were benzalkonium chloride (BAC), sodium ethylenediaminetetraacetate (EDTA), polyoxyethylene-20-stearyl ether (PSE), polyethoxylated castor oil (PCO), deoxycholic acid sodium salt (DC) and cetylpyridinium chloride (CPC). For these substances, definite correlations were found between promoting activity for permeation of TM and modification of electrophysiological parameters. These parameters were in all cases significantly altered by all agents at all concentrations after a 5-h contact. However, after a 1-h contact, 0.001% PSE and CPC did not significantly modify the corneal resistance, while PCO and PSE did not significantly modify the transcorneal potential at the tested concentrations. Only 0.001% PSE, a nonionic surfactant used as solubilizer and emulsifier, active as promoter for TM, did not modify both electrophysiological parameters to a significant extent after 1 h. The results of this study indicate correlations between ocular toxicity, promoting activity for transcorneal permeation of timolol and modification of the electrophysiological parameters. [Copyright &y& Elsevier]

• Montmorillonite (Mt) was modified using CPC, to reverse the zeta potential of Mt to positive. • FTIR, XRD, SEM and molecular dynamics simulation were performed to confirm the modification. • CPC-Mt removed Cr (VI) efficiently, but the removal decreased as increasing pH and ionic strength. • Cr (VI) removal was achieved by ion exchange and reduction to Cr (III) in CPC-Mt. Montmorillonite (Mt) has been used widely for metal removal from water and wastewater due to its various advantages including low cost, large surface area, high structure stability, and high ion exchange capacity. However, the removal of anionic hexavalent chromium (Cr) using Mt is inhibited by the negative charges on the adsorbent. To enhance Cr (VI) adsorption on Mt, a cationic surfactant – cetylpyridinium chloride (CPC) – was utilized to modify the interlayer surface of Mt. Fourier-transform infrared spectroscopy and X-ray diffraction were performed to characterize the CPC modified Mt (CPC-Mt) and the structure change of Mt. Studies have shown that CPC intercalated into Mt interlayers via electrostatic interaction between Mt and CPC, as well as the hydrophobic interaction among CPC molecules. After modification, the CPC-Mt showed a positive zeta potential at pH 2–11; while the specific surface area decreased, CPC effectively increased the interlayer distance of Ca-Mt, with a maximum d 001 value of 4.37 nm, and provided more exchange sites for Cr (VI) adsorption. Cr (VI) was efficiently removed using CPC-Mt at low pH values, but the removal was influenced adversely by the increase of pH and ionic strength. The adsorption process was described by a Langmuir isotherm model with the constant of 0.342 L/mg and the maximum adsorption capacity of 43.84 mg/g at 298 K, and by a pseudo-second order kinetic model with a kinetic coefficient of 6.62 g/(mg·min). The adsorption mechanism analysis has shown that electrostatic attraction is the main mechanism for Cr (VI) removal; at the same time, the reduction of Cr (VI) to Cr (III) by Fe (II) in Mt cannot be neglected at low pH values, which increased Cr removal and was confirmed by the X-ray photoelectron spectroscopic analysis. [ABSTRACT FROM AUTHOR]