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Aim: To compare the shear bond strength and penetration ability of self-etch sealant with and without enamel deproteinization. Materials and methods: A total of 37 sound extracted teeth were selected and 31 teeth were used for testing shear bond strength of self-etch sealant. For this, crowns portions of selected teeth were cut longitudinally with a diamond disc into a mesial and distal half, thereby yielding 62 samples. They were further divided into two groups; in Group 1, samples were deproteinised with 5.25% sodium hypochlorite and a sealant cylinder was built on the proximal surface. In Group 2, sealant cylinders were built without deproteinising the surface. Shear bond strength was tested using Universal Testing Machine. The remaining six teeth were used for penetration evaluation of self-etch sealant. In Group 1, the occlusal surface was deproteinised with 5.25% sodium hypochlorite and self-etch sealant was directly applied. In Group 2, sealant was applied without deproteinisation. The samples obtained after sectioning were observed under scanning electron microscope for sealant penetration. Mann–Whitney test and Chi-square analysis were utilised for statistical analysis. Results: The results showed that the shear bond strength of the two groups was statistically not significant (p = 0.23). However, the comparison of % penetration revealed a statistically significant difference between the groups (p = 0.016). Conclusion: Deproteinising the enamel surface prior to application of self-etch sealant enhanced the penetration ability of the sealant but did not show any effect on shear bond strength. [ABSTRACT FROM AUTHOR]

Acetazolamide 1 is a carbonic anhydrase inhibitor used in the medical treatment of glaucoma, epileptic seizure, idiopathic intracranial hypertension, altitude sickness, etc. The synthesis of acetazolamide from the corresponding thiol derivative 4 requires oxidation and converting it to the sulfonyl chloride intermediate 5. This research aimed to enhance the safety, environmental conditions, and efficiency of the oxidation process by substituting chlorine gas for sodium hypochlorite (commercial bleach). The use of chlorine gas in place of conventional oxidation methods offered significant benefits, including the synthesis of several novel compounds with a high level of purity, specifically designated as 6a-6f. These novel compounds were produced through the reaction of synthesized key sulfonyl chloride 5 with various amines, hydrazones, and bis-amine precursors, leading to the creation of new sulfonamide derivatives. A thorough investigation was conducted to determine the antibacterial activity (ABA) and antioxidant activity (AOA) of the newly synthesized compounds. The results indicated that the ABA impact of the prefabricated bis-products (7a and 7b) was significantly higher than that of the standard mono-product (6a). This suggests that the bis-products possess enhanced antibacterial properties compared to their mono-product counterparts. Moreover, the hydrazine-based products synthesized (8a-8g) demonstrated remarkable efficacy against both Gram-positive and Gram-negative bacteria. These products, particularly compound 9g, showed superior antibacterial effects when compared to commonly used antibiotics such as ciprofloxacin and tetracycline. This highlights the potential of these new compounds as effective antibacterial agents. In terms of antioxidant activity, a comparison with ascorbic acid revealed that compounds 9c, 9a, 9b, 9e, and 8d exhibited superior AOA. This indicates that these compounds have a strong potential to act as antioxidants, which can be beneficial in various applications where oxidative stress is a concern. In summary, the substitution of chlorine gas for sodium hypochlorite in the oxidation process not only improved safety and environmental conditions but also led to the efficient synthesis of highly pure novel compounds. These compounds displayed significant ABA and AOA, suggesting their potential as valuable agents in medical and industrial applications. The enhanced properties of the bis-products and hydrazine-based compounds, in particular, underscore the importance of this research in developing new, effective chemical entities. Future research will focus on further optimizing these compounds for clinical use, evaluating their pharmacokinetics and toxicity profiles, and exploring their applications in other therapeutic areas such as anticancer and antiviral treatments. [ABSTRACT FROM AUTHOR]

For successful root canal treatment, adequate chemomechanical instrumentation to eliminate microorganisms and pulp tissue is crucial. This study aims to assess the organic tissue dissolving activity of various irrigation solutions on bovine tooth pulp tissue. 40 extracted bovine mandibular anterior teeth (n = 10) were used for the study. Bovine pulp pieces (25 ± 5 mg) were placed in 1.5 ml Eppendorf tubes. Each tooth pulp sample was then covered with 1.5 ml of different irrigation solutions, dividing them into four groups: Group 1 with freshly prepared 5% Boric acid, Group 2 with 5% NaOCl, Group 3 with Irritrol, and Group 4 with Saline. Samples were left at room temperature for 30 min, then dried and reweighed. The efficacy of tissue dissolution ranked from highest to lowest was found to be NaOCl, Boric Acid, Irritrol, and saline (p < 0.05). It was observed that the decrease in the NaOCl group was greater than the decrease in the Irritrol and saline groups, and the decrease in the Boric acid group was significantly greater than the decrease in the saline group (p < 0.05). It also emphasizes the need for future studies to further investigate the effects of Irritrol and Boric Acid on tissue dissolution. [ABSTRACT FROM AUTHOR]

This research work undertakes root cause failure analysis of fractured glass fiber-reinforced polymer composite pipe. A sequential macro- and micro-level investigation was performed to disclose the potential failure cause. Results showed that swelling on the pipe was attributed to water absorption during the service life of the pipe. The corrosion barrier in the form of resin-rich liner on the pipe interior deteriorated and was removed by chemical attack. Resin removal caused exposure of reinforcing fibers to harsh sea environment. Diffusion of water within the matrix accelerated the corrosion attack by sodium hypochlorite solution, which was being pumped through the pipe toward brine de-chlorination area. Micro-examination indicated that the fiber–matrix interface was chemically attacked by sodium hypochlorite solution, significantly reducing pipe structural integrity. The carbon, hydrogen and chlorine bonds in the internal surface had undergone prominent bond stretching, which was generally attributed to oxidation. The swelling and deformation in the pipe indicated that the fluid was being held in the pipe for longer duration than the maximum specified time as per design, which ultimately led to the failure. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to compare the antimicrobial action, cytotoxicity, cleaning ability, and erosion of dentine of hypochlorous acid (HClO) obtained from an electrolytic device at two different concentrations (Dentaqua) and three concentrations of sodium hypochlorite (NaOCl). Methods: Microbiological test—The root canals of sixty single-rooted extracted human teeth were inoculated with Enterococcus faecalis and divided into 6 groups (n = 10), according to decontamination protocol: DW (control); 1% NaOCl; 2.5% NaOCl; 5.25% NaOCl; 250 ppm HClO and 500 ppm HClO. The colony-forming units were counted to evaluate the decontamination potential of each group, calculating the reduction in bacterial percentage. Cytotoxicity test—Cytotoxicity was evaluated after inoculation of the same tested protocols in fibroblastic cells for 3 min, calculating the cell viability percentages. Specifical statistical analysis was performed (α = 5%). Cleaning ability and erosion—Fifty-six single-rooted bovine lower incisors were divided into seven groups of 8 roots each, being the test groups 1% NaOCl; 2.5% NaOCl; 5,25% NaOCl; 250 ppm HClO and 500 ppm HClO, and a negative and positive control. Negative control was not contaminated, and the other groups were inoculated with Enterococcus faecalis. SEM images were ranked as from the cleanest to the least clean. Erosion was also assessed, being ranked from the least to the most eroded dentine. Results: The highest bacterial reduction was observed in experimental groups, with no statistical differences between them (p > 0.05). The highest number of viable cells was observed in control group, followed by 250 ppm HClO and 500 ppm HClO groups, with statistical differences between them (p < 0.05). 1% NaOCl; 2.5% NaOCl; 5.25% NaOCl and 500 ppm HClO displayed the cleanest areas. All sodium hypochlorite groups displayed erosion with higher ranks with greater concentration, while hypochlorous acid did not display any erosion regardless the concentration. Conclusions: It is possible to conclude that HClO obtained from an electrolytic device presented high antimicrobial activity and low cytotoxicity in both tested concentrations. 500 ppm HClO did not display erosion and showed great cleaning ability. Clinical relevance: The use of 500 ppm hypochlorous acid may reduce unfavorable behavior of sodium hypochlorite whilst maintaining its antimicrobial action. [ABSTRACT FROM AUTHOR]

Annual fertilizer demand can be affected by population, economics, and food prices. Organic fertilizer lasts longer than mineral fertilizer. Plants prefer easily absorbed liquid nutrients. Uncooked rice berry water was utilized in this study according to the innovative biorefinery concept. The effects of sodium hypochlorite (NaOCl) in MS medium at five different concentrations (0, 0.5, 1, 2, and 3%) for 7 days without using an autoclave were measured; the results showed that MS medium with 2.3% NaOCl had the highest sterilization rate. The strawberry cultivar Praratchatan No. 80 seeds were then cultivated on a NaOCl-MS medium. The findings indicate MS medium enhanced productivity by 1%. The most shoots (8.56±0.34 shoots/explant) were produced by NaOCl, while MS media produced the most roots (5.55±0.78 roots/explant). The strawberry cultivar seeds were also cultivated on NaOCl-MS medium supplemented with uncooked rice berry wastewater at five different concentrations (0, 5, 10, 15, and 20%), as well as a combination of BA at 2 mg/L and NAA 0.1 mg/L. The results showed that MS medium supplements containing 10% uncooked rice berry wastewater + 2 mg/L BA + 0.1 mg/L NAA produced the most shoots (13.21±0.32 shoots/explant) and 2% NaOCl-MS medium + 10% uncooked rice berry wastewater produced the most roots (18.07±0.20 shoots/explant). This study found that MS medium supplemented with uncooked rice berry wastewater gave the best results regarding the growth in shoot and root production. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effectiveness of two sodium hypochlorite concentrations at different exposure times and temperatures against Enterococcus faecalis biofilms of varying ages in human dentinal tubules. Dentin blocks were infected with E. faecalis for either 3 days or 3 weeks of incubation. Subsequently, the samples were exposed to sterile water, 2%, and 5.25% sodium hypochlorite for 3 and 10 min at 20 °C and 60 °C. Viability staining and confocal laser scanning microscopy were used to assess the proportion of killed bacteria in the dentinal tubules after exposure. There are no significant differences in the efficacy of E. faecalis killing between 2% sodium hypochlorite at 60 °C for various exposure times and 5.25% sodium hypochlorite at different temperatures or exposure times (P > 0.05). When both solutions were compared at the same temperatures with a 10-min exposure time, no significant differences in the effectiveness of E. faecalis killing between 2% and 5.25% sodium hypochlorite were observed (P > 0.05). To optimize the effectiveness of sodium hypochlorite in killing E. faecalis while minimizing potential damage to root dentin and soft tissue, clinicians should prioritize increasing the temperature or exposure time of sodium hypochlorite, rather than raising its concentration. [ABSTRACT FROM AUTHOR]

The aim was to investigate the influence of endodontic irrigation solutions and protocols on the micro-tensile bond strength (μTBS) to dentin using an etch-and-rinse (ER) or self-etch (SE) adhesive approach. Eighty extracted human molars were ground to dentin. After pretreating for 27 min (21 min–3 min–3 min) with five different endodontic irrigation protocols (Group 1: NaOCl–EDTA–NaOCl; Group 2: NaOCl–NaOCl–EDTA; Group 3: NaOCl–NaCl–NaOCl; Group 4: Dual Rinse–Dual Rinse–Dual Rinse; Group 5: NaCl–NaCl–NaCl), an ER (Optibond FL, Kerr) or a SE (Clearfil SE Bond, Kuraray) adhesive system was applied. After light-curing, composite build-ups were made and cut into dentin-composite sticks. μTBS and failure modes were analyzed. Nonparametric statistical analyses (α = 0.05) were performed for comparison of the five groups within each type of adhesive as well as between the two adhesive systems used. The use of an ER instead of a SE adhesive system resulted in significantly higher μTBS for all irrigation protocols except for group 1 (NaOCl–EDTA–NaOCl) and 2 (NaOCl–NaOCl–EDTA). A statistical difference between the five different endodontic irrigation protocols was only found within the SE adhesive group, where group 1 (NaOCl–EDTA–NaOCl) achieved highest values. The use of an ER adhesive system cancels out the effect of the endodontic irrigation solution. The highest μTBS was achieved when using a NaOCl–EDTA–NaOCl-irrigation protocol in combination with Clearfil SE Bond, which shows that the selection of the endodontic irrigation should match the corresponding SE adhesive system. [ABSTRACT FROM AUTHOR]

The present study was conducted in the Laboratory of Tissue Culture, Horticulture Department, Faculty of Agriculture, Damietta University, Egypt. The objective of this study was to establish a micropropagation protocol suitable for three imported peach rootstocks: Okinawa (P. persica), Nemared (P. persica × P. davidiana) × P. persica), and Garnem (P. dulcis × P. persica) in vitro. The results showed that soaking the explants in sodium hypochlorite (NaOCl) at 20% for 15 min produced the highest responsiveness (82.81%), survival (96.61%), with the lowest mortality (3.14%) and contamination (0.24%). Explants of the Garnem genotype had the best response (89.12%), survival (90.62%), lowest mortality (0.00%), and highest contamination (9.37%) when compared to the other genotypes. In comparison with axillary buds, the shoot tip displayed the highest responsiveness, survival, and death (100, 87.40, and 12.59%, respectively), as well as the least significant contamination (0.00%). Additionally, the percentages of responsive, survived, dead, and contaminated explants at the various collection dates varied significantly. The 6-benzylaminopurine (BAP) concentrations used (3 to 5.0 mg/L) demonstrated similar behavior in terms of in vitro proliferation, with rates of 3.77 to 6.11, 4.33 to 8.88, and 3.33 to 7.44 shoot numbers per explant for the Okinawa, Nemared, and Garnem peach rootstocks, respectively, indicating that the number of shoot proliferations is genotype-dependent. Additionally, using 5.0 mg/L BAP in combination with 0.2 mg/L IBA significantly increased average shoot proliferation (96.29%), number of shoots per explant (7.48), and average leaf number/explant (16.33) compared to the other treatments. Based on these results, adventitious bud development was enhanced during in vitro multiplication of the Okinawa, Nemared, and Garnem peach rootstocks by the synergistic interaction of indole-butyric acid (IBA) and 6-benzylaminopurine (BAP). [ABSTRACT FROM AUTHOR]

Objectives: An adjunct in non-surgical periodontal therapy might be sodium hypochlorite (NaOCl)–based agents. The purpose of the present in vitro study was to get deeper knowledge on the influence of different parameters as time after mixing, pH, and chemical composition of an amino acid 0.475% NaOCl (AA-NaOCl) gel consisting of two components on its anti-biofilm activity. Materials and methods: Six-species biofilms were cultured for 5 days, before AA-NaOCl gel was applied. In the different series, the influence of the time after mixing of the two components before application, of the concentration of NaOCl in the gel mixture, of the pH of the gel mixture, and of an exchange of the amino acid component by hyaluronic acid (HA), was analyzed. Results: Mixing time point experiments showed that the AA-NaOCl gel is capable of statistically significantly reducing colony-forming unit (cfu) counts up to 30 min after mixing, but only up to 20 min after mixing the reduction was more than 2 log10 cfu. The pH experiments indicate that a reduced pH results in a reduced activity of the NaOCl formulation. NaOCl concentrations in the formulation in the range from 0.475 to 0.2% provide adequate activity on biofilms. A HA/NaOCl gel was equally active against the biofilm as the AA-NaOCl gel. Conclusion: Mixing of the components should be made in a timeframe of 20 min before applications. An optimization of the composition of the NaOCl formulation might be possible and should be a topic in further in vitro studies. Clinical relevance: The AA-NaOCl gel formulation can be mixed up to 20 min before application. Further, the study indicates that the composition of the NaOCl gel formulation can be optimized. [ABSTRACT FROM AUTHOR]

The reaction of aminoamides of the furo[2,3-b]pyridine series with an aqueous solution of sodium hypochlorite and N-chlorosuccinimide was studied. It was found that the chlorination reaction proceeds at position 2 of the furopyridine system, leading to previously unknown 3-imino-2-chlorofuro[2,3-b]pyridine-2-carboxamides. For some synthesized compounds, nucleophilic substitution reactions were investigated. Among the obtained substances, compounds were identified that have antidote activity against 2,4-D. [ABSTRACT FROM AUTHOR]

Polyhydroxybutyrate (PHB) is known for wide applications, biocompatibility, and degradability; however, it cannot be commercialized due to conventional recovery using solvents. The present study employed mechanical cell-disruption methods, such as Pestle and mortar, sonication, and glass bead vortexing, for solvent-free extraction of PHA from Bacillus sp. Different time intervals were set for grinding (5, 10, 15 min), sonicating (1, 3 and 5 min), and vortexing (2, 5 and 8 g glass beads with 5, 10 and 15 min each) hence studying their effect on cell lysis to release PHA. Tris buffer containing phenylmethyl sulfonyl fluoride (PMSF) (20 mM Tris–HCl, pH 8.0, 1 mM PMSF) was employed as a lysis buffer to study its action over Bacillus cells. Its presence was checked with the above methods in cell lysis. Sonicating cells for 5 min in the presence of lysis buffer achieved a maximum PHA yield of 45%. Cell lysis using lysis buffer yielded 35% PHA when vortexing with 5 g glass beads for 15 min. Grinding cells for 15 min showed a maximum yield of 34% but lacked a lysis buffer. The overall results indicated that the action of lysis buffer and physical extraction methods improved PHA yield by %. Therefore, the study sought to evaluate the feasibility of applying laboratory methods for cell disruption. These methods can showcase possible opportunities in large-scale applications. The polymer yield results were compared with standard sodium hypochlorite extraction. Confirmation of obtained polymers as polyhydroxy butyrate (PHB) was made through FTIR and 1HNMR characterization. [ABSTRACT FROM AUTHOR]

Objectives: This study evaluated the antimicrobial activity, clinical and radiographic outcome of pulpectomy in primary teeth using either 1% sodium hypochlorite (NaOCl) or 2% chlorhexidine (CHX) as irrigants. Materials and methods: A randomized double-blind controlled clinical study in which primary teeth were allocated to 1% NaOCl (n = 20) and 2% CHX (n = 20) groups. Microbiological collections were performed before and after irrigation for agar culture and real-time polymerase chain reaction (qPCR). Clinical and radiographic success was assessed at different times. Data were submitted to descriptive analysis, chi-square, Mann–Whitney, and Wilcoxon tests (p <.05). Results: For 1% NaOCl, the following clinical and radiographic success rates were observed: 7 days (93%/80%); 30 days, 3 and 6 months (100%). For 2% CHX: 7 days (73%/53%); 30 days (93%); 3 months (100%/93%); 6 months (100%) (p >.05). One percent NaOCl and 2% CHX effectively reduced total microorganisms (p <.05) but not mutans streptococci (p >.05). In qPCR analysis, the solutions promoted a reduction of total bacteria and Streptococcus mutans, and no difference was observed between times and groups (p >.05). Conclusions: One percent NaOCl and 2% CHX were effective for clinical and radiographic success and antimicrobial activity in primary teeth submitted to pulpectomy. Clinical relevance: Studying the antimicrobial activity and clinical and radiographic outcomes of pulpectomy in primary teeth using NaOCl and CHX as irrigants is clinically relevant because it provides information for optimizing treatment protocols and improving the quality of care for pediatric patients. It contributes to evidence-based practice and can potentially lead to better outcomes, reduced complications, and enhanced patient experiences. [ABSTRACT FROM AUTHOR]

Manure effluents (MEs) of livestock enterprises represent a rich nutrient medium for the development of various aerobic microorganisms (MOs). A wide range of odor-forming substances (OFSs) and greenhouse gases enter the atmosphere as a result of the biodegradation of the organic components of the MEs. The intensity and main directions of ME destruction depend on the composition and abundance of the microbiota. A solution of sodium hypochlorite can be used to suppress the processes of decomposition of the biogenic components of the MEs. In the process of research, it was found that the introduction of 0.005% active chlorine into the liquid ME fraction (pH 6.8; humidity 99.1%) leads to a decrease in the number of representatives of putrefactive microbiota such as Bacteroides spp., Clostridium spp., Escherichia coli, Pseudomonas spp., Sarcina ventriculi, and Peptostreptococcus anaerobius. The corresponding ammonifiers take an active part in the processes of biodegradation of organic substances, which result in the formation of acetic, isovaleric, butyric acids, indoles, skatoles, ammonia, hydrogen sulfide, mercaptans, etc. On the contrary, the amount of microbiota that does not make a significant contribution to the production of OFSs (Saccharomyces cerevisiae, Rhodotorula glutinis, Lactobacillus spp., etc.) increased. The number of some producers of volatile fatty acids (VFAs), like Anaerococcus prevotii, Acidaminococcus spp., Prevotella spp., etc., increased; however, they did not have a noticeable effect on the intensity and nature of the ME odor, which may be explained by the formation of nonvolatile VFA salts at pH above 7.0. The amount of Staphylococcus aureus, Staphylococcus epidermidis, Klebsiella sp., Proteus spp., Alistipes putredinis, Bifidobacterium spp., Candida tropicalis, and Candida albicans practically did not change when NaOCl was added to the MEs. The total emission of gaseous substances, the main components of which are greenhouse gases CO2 and CH4, decreased by more than 17% as a result of the transformation of the microbiota. The intensity of the unpleasant odor was significantly reduced. The NaOCl solution can be used for ME treatment in manure tanks. The introduction of the practice of treating MEs with this biocide is facilitated by its availability, low cost, and safety for the environment. [ABSTRACT FROM AUTHOR]

Ultrafiltration (UF) is widely used in wastewater reclamation treatments. Conventional backwashing is usually performed at regular time intervals (10–120 min) with permeate and without the addition of chemicals. Chemical enhanced backwashing (CEB) is usually applied after 70–90 filtration cycles with added chemicals. These cleaning methods cause membrane fouling and require costly chemicals. Instead of conventional backwashing, we propose herein a new backwashing method involving backwashing the effluent with low doses of sodium hypochlorite (NaClO) named as BELN. The performance and cost of UF backwashing were investigated with Beijing wastewater reclamation treatment. The results showed that the transmembrane pressure (TMP) increased from 33.2 to 48.2 kPa during hydraulic backwashing after 80 filtration cycles but increased from 33.3 to 39.3 kPa during backwashing with a low NaClO content of 20 mg/L. It was also noticed that the hydraulic-irreversible fouling index decreased from 5.58 × 10−3 m2/L to 3.58 × 10−3 m2/L with the new method. According to the three-dimensional fluorescence excitation-emission (3D-EEM), the response increased from 11.9 to 15.2% with BELN. Protein-like material was identified as the main component causing membrane fouling by blocking the membrane pores. The results indicated that the low dosage of NaClO effectively stripped the fouling layer. Finally, based on an economic evaluation, the capacity of the UF process was increased from 76,959 to 109,133 m3/d with the new method. The amount of NaClO consumed for Beijing wastewater reclamation treatment was similarly compared with the conventional backwashing in per year under BELN. The new method has good potential for application. [ABSTRACT FROM AUTHOR]

Objectives: To comparatively evaluate the nisin-incorporated ethylenediamine tetraacetic acid (N-EDTA) and MTAD on cytotoxicity, endodontic biofilm eradication potential, smear layer removal ability, and sealer penetration depth. Materials and methods: N-EDTA was prepared and characterized using high-performance liquid chromatography (HPLC). Minimum inhibitory, minimum bactericidal, and minimum biofilm inhibitory concentration (MBC, MIC, and MBIC) were determined on Enterococcus faecalis (E. faecalis) strain. The cytocompatibility of N-EDTA and MTAD was evaluated using 3,(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-based colorimetric assay. Dentin specimens (n = 88 for antibacterial analysis, n = 170 for sealer penetration depth) were prepared and subjected to the classical irrigating strategy and obturation, respectively. The scanning electron microscopic evaluation (SEM) was done for the evaluation of biofilm disruption and smear layer removal. Confocal laser scanning microscopy (CLSM) evaluation was done for determining percentage of bacterial viability and sealer penetration depth. Statistical analysis of one-way ANOVA and Tukey's HSD post hoc tests for bacterial viability and Kruskal-Wallis test and Mann-Whitney test for smear layer removal and depth of penetration were done with the significance level set at p < 0.05. Results: MTAD and N-EDTA showed cytocompatibility without any statistical differences from each other. For N-EDTA, the MIC and MBC values were 12.5 μg/ml (1:8), and MBIC values were 36 μg/ml. Biofilm disruption and killed bacterial percentage of N-EDTA was statistically higher than MTAD, whereas both the materials showed similar efficacy in the removal of the smear layer and sealer penetration depth. Conclusion: N-EDTA had negligible cytotoxicity with similar smear layer removal ability, sealer penetration, and better antibiofilm potential than MTAD. Clinical relevance: N-EDTA can serve as a viable alternative endodontic irrigant. [ABSTRACT FROM AUTHOR]

A review of studies in the field of oxidation of organic substrates with sodium hypochlorite, published in the past 15–20 years, is presented. Oxidation of primary and secondary alcohols, epoxidation of olefins, oxidative desulfurization, and nitrogen oxide oxidation are described. A comparative analysis of various catalytic systems used in this field is made. Industrial uses of sodium hypochlorite, in particular, for wastewater treatment, are described. The main directions of using sodium hypochlorite and the related prospects and problems are outlined. [ABSTRACT FROM AUTHOR]

Objectives: To compare the clinical outcomes obtained with either mechanical subgingival debridement in conjunction with a sodium hypochlorite and amino acids containing gel followed by subsequent application of a cross-linked hyaluronic acid gel (xHyA) gel, or with mechanical debridement alone. Materials and Methods: Fourty-eight patients diagnosed with stages II-III (Grades A/B) generalised periodontitis were randomly treated with either scaling and root planing (SRP) (control) or SRP plus adjunctive sodium hypochlorite/amino acid and xHyA gels (test). The primary outcome variable was reduction of probing depth (PD), while changes in clinical attachment level (CAL), bleeding on probing (BOP) and plaque index (PI) were secondary outcomes. The outcomes were assessed at baseline, at 3 and 6 months following therapy. Results: All patients completed the 6 months evaluation. At 6 months, the test group showed statistically significantly better results in terms of mean PD reduction (2.9 ± 0.4 vs 1.8 ± 0.6 mm, p < 0.001). Similarly, mean CAL gain was statistically higher in the test group compared to the control one (test: 2.6 ± 0.5 vs control: 1.6 ± 0.6 mm, p < 0.001). Mean BOP decreased from 81.8 ± 16.2% to 48.9 ± 14.5% in control (p < 0.001) and from 83.2 ± 15.5% to 17.6 ± 11.5% in test (p < 0.001) groups with a statistically significant difference favouring the test group (p < 0.001). Mean PI scores were reduced statistically significantly in both groups (from 38.8 ± 26% to 26.5 ± 20.5% in control (p = 0.039) and from 60.6 ± 10.9% to 12.7 ± 8.9% in test group (p < 0.001)), with a statistically significant difference between the groups (p < 0.001). The number of moderate pockets (4–6 mm) were reduced from 1518 (41.2%) to 803 (22.6%) in the control and from 1803 (48.6%) to 234 (7.7%) in the test group with a statistically significant difference between the groups (p < 0.001), while the number of deep pockets (≥ 7 mm) changed from 277 (7.6%) to 35 (1.0%) in the control and from 298 (8.7%) to 4 (0.1%) in test group (p = 0.003). Conclusion: Within their limits the present data indicate that: a) both treatments resulted in statistically significant improvements in all evaluated clinical parameters, and b) the adjunctive subgingival application of sodium hypochlorite/amino acid and xHyA to SRP yielded statistically significantly higher improvements compared to SRP alone. Clinical relevance: The combination of sodium hypochlorite/amino acid and xHyA gels to subgingival mechanical debridement appears to represent a valuable approach to additionally improve the outcomes of non-surgical periodontal treatment. Clinical Trial Registration Number NCT04662216 (ClinicalTrials.gov). [ABSTRACT FROM AUTHOR]

Objective: This systematic review/meta-analysis investigated the influence of NaOCl on cyclic fatigue resistance of endodontic NiTi instruments. Materials and methods: A systematic search until July 2022 in PubMed/MEDLINE, Embase, Scopus, Web of Science, SciELO, Cochrane Library, and grey literature was conducted. According to the PECOS strategy, only in vitro studies evaluating the effects of NaOCl on the cyclic fatigue resistance of NiTi instruments were eligible. Cyclic fatigue resistance was the primary outcome. A modified Joanna Briggs Institute's Checklist was used for risk of bias assessment. Results: Of the 2,445 records screened, 37 studies were included. Most studies used simulated canals made of stainless-steel block with severe to moderate curvatures. NaOCl concentration varied from 1–6%, mainly at 37 °C. Regarding fatigue resistance, 23 studies using 1.2% to 6% NaOCl showed a reduction in the resistance compared to the control groups, especially when pre-heated. Four meta-analyses were performed according to the tested NiTi systems. The meta-analyses indicated that the PTU F2 files had higher reduction of fatigue resistance after exposure to 5.25% NaOCl; no differences between NaOCl and no immersion were observed for Reciproc R25, WaveOne 25.08, and WaveOne Gold Primary files. Included studies had low risk of bias. Conclusion: NaOCl appears to reduce cyclic fatigue resistance of certain NiTi files, especially when they are pre-heated, particularly in conventional NiTi files compared to some heat-treated instruments. It is possible that the temperature of the solution may have a greater influence on resistance than NaOCl itself. Important to note that an overall tendency toward no significant influence was observed among various systems. Clinical relevance: Precautions are necessary when a pre-heated high-concentration NaOCl is used to enhance its properties during root canal preparation, mainly using conventional wire. [ABSTRACT FROM AUTHOR]

With N,N′-methylenebisacrylamide (MBA) and polyvinyl alcohol (PVA) as raw materials, a polymer (PVA-MBA) containing N-halamine precursor functional groups was obtained via grafting reaction between the active hydroxyl groups on PVA and α, β-unsaturated functional groups of MBA under the catalysis of sodium carbonate in an aqueous solution. An acyclic N-halamine precursor-grafted PVA (MBA-PVA) film was formed by simply spreading PVA-MBA aqueous solution in a glass dish and drying it. An antimicrobial acyclic N-halamine-grafted PVA (PVA-MBA-Cl) film was achieved by spraying the diluted sodium hypochlorite solution onto the surface of PVA-MBA film. The performance test of PVA-MBA-Cl film under the optimal preparation conditions showed that the tensile performance and the hydrophobicity were improved, compared to the PVA film. The storage stability test indicated that the oxidative chlorine content Cl+ (atoms/cm2) of the as-prepared PVA-MBA-Cl film only reduced by 14.3% after storage for 9 weeks, showing that the antibacterial N-halamine functional groups in PVA-MBA-Cl film has excellent storage stability under room temperature. Antibacterial test showed that the PVA-MBA-Cl film had very strong antibacterial efficacies and could completely kill 1.28 × 106 CFU/mL S. aureus and 1.89 × 106 CFU/mL E. coli within 1 min. Therefore, PVA-MBA-Cl film will have more potential applications in food package. [ABSTRACT FROM AUTHOR]

In this work, in order to intensify the oxidation of starch with sodium hypochlorite, mechanical activation of starch suspension in a rotor-stator device (RSD) was used for the first time. Activation of starch suspension (concentrations of 10, 20, 30 and 40%) before oxidation was carried out for 10, 20, and 30 s in two ways: either before the introduction of the oxidizing agent (A-OS) or after its introduction (AOS). The activation of starch in RSD for 10–30 s increased the rate of oxidant consumption during subsequent oxidation. The oxidized starches were analyzed by scanning electron microscopy (SEM), X-ray diffraction, and FTIR spectroscopy. Mechanical activation caused erosion of starch granules, increased porosity and specific surface areas.The mechanical activation of the starch increased the content of carbonyl groups in the range 46–61% and that of carboxyl groups in the range 60–100%, compared with the oxidation without activation (OS). In the case of (AOS), a higher yield of carbonyl and carboxyl groups was achieved compared to (A-OS). It was found that the effective viscosity and consistency coefficient of the starch hydrogels monotonically decrease as the duration of preactivation of the starch suspensions increased. Mechanical activation in RSD can be used to improve the oxidizing degree of oxidized starch or to reduce process time on a large scale. [ABSTRACT FROM AUTHOR]

Proper disinfection and inactivation of highly pathogenic viruses is an essential component of public health and prevention. Depending on environment, surfaces, and type of contaminant, various methods of disinfection must be both efficient and available. To test both established and novel chemical disinfectants against risk group 4 viruses in our maximum containment facility, we developed a standardized protocol and assessed the chemical inactivation of the two Ebola virus variants Mayinga and Makona suspended in two different biological soil loads. Standard chemical disinfectants ethanol and sodium hypochlorite completely inactivate both Ebola variants after 30 s in suspension at 70% and 0.5% v/v, respectively, concentrations recommended for disinfection by the World Health Organization. Additionally, peracetic acid is also inactivating at 0.2% v/v under the same conditions. Continued vigilance and optimization of current disinfection protocols is extremely important due to the continuous presence of Ebola virus on the African continent and increased zoonotic spillover of novel viral pathogens. Furthermore, to facilitate general pandemic preparedness, the establishment and sharing of standardized protocols is very important as it allows for rapid testing and evaluation of novel pathogens and chemical disinfectants. [ABSTRACT FROM AUTHOR]

This study aimed to comparatively evaluate the disinfecting potential of sodium hypochlorite, diode laser, and photodynamic therapy in non-vital teeth with or without periapical rarefaction. Forty-five patients with the diagnosis of pulp necrosis with apical rarefaction were randomly assigned to three groups (n = 15) based on the disinfection protocol. Access cavities were prepared and pre-instrumentation microbial samples were taken using a paper point. Working length determination followed by cleaning and shaping with rotary files was performed. The canals were lubricated with ethylenediaminetetraacetic acid (EDTA) during instrumentation and finally rinsed with copious amounts of saline. Canals in group 1 were irrigated with 5 mL of 5.25% NaOCl, those in group 2 received irradiation with 808-nm diode laser (30 s, 7W), and those in group 3 were soaked with methylene blue photosensitizer (5 min) before irradiation with 660-nm diode laser (3 min). Post-disinfection microbial samples were collected using a paper point. Pre- and post-disinfection live bacterial counts were analyzed using a flow cytometer. The data were statistically analyzed using one-way ANOVA and Student's t-test. Comparison of pre-instrumentation mean live bacterial count showed no significant difference between the groups (p > 0.05). The mean live bacterial count post-disinfection was 41.07%, 46.99%, and 34.45% in groups 1–3 respectively. A significant reduction in the bacterial count was seen following disinfection in all the groups (p < 0.05). It can be concluded that both diode laser and photodynamic therapy were equally effective as 5.25% NaOCl in reducing the bioburden in root canals. Trial registration: CTRI/2018/03/012667. [ABSTRACT FROM AUTHOR]

Functional endoscopic sinus surgery (FESS) is the gold standard treatment for medically refractive chronic rhinosinusitis, aimed at removing diseased tissue and improving natural sinus drainage and aeration. Irrigation of the sinuses has been known to improve sinus mucosal health and is an essential adjunct to surgery. There are a number of methods, devices, and solutions available which are used for nasal irrigation. Neti Pot, squeeze bottle, syringe, rubber bulb and commercially available nasal sprays are some of the simpler used devices used for douching. Electric devices like flosser, Hydropulse and the Navage nasal irrigation systems are available but it's not clear if they provide any advantage over the other methods. We use and propose a gravitational pressure-pulsed device which provides adequate volume and force without the need for external pressure. Salt with sodium bicarbonate is the most used solution base. Hypertonic saline has been described to be more efficacious compared to isotonic saline. Additives such as sodium hypochlorite, antibiotics, corticosteroids, manuka honey and xylitol have proven to be beneficial. Large volume positive pressure irrigations have proven to be beneficial. Optimal position for irrigation varies for low or high-volume irrigation systems. Patient education regarding precautions and disinfection of the device is a must. [ABSTRACT FROM AUTHOR]

The World Health Organization's R&D Blueprint list of priority diseases for 2022 includes Lassa fever, signifying the need for research and development in emergency contexts. This disease is caused by the arenavirus Lassa virus (LASV). Being an enveloped virus, LASV should be susceptible to a variety of microbicidal actives, although empirical data to support this expectation are needed. We evaluated the virucidal efficacy of sodium hypochlorite, ethanol, a formulated dual quaternary ammonium compound, an accelerated hydrogen peroxide formulation, and a p-chloro-m-xylenol formulation, per ASTM E1052-20, against LASV engineered to express green fluorescent protein (GFP). A 10-μL volume of virus in tripartite soil (bovine serum albumin, tryptone, and mucin) was combined with 50 μL of disinfectant in suspension for 0.5, 1, 5, or 10 min at 20–25 °C. Neutralized test mixtures were quantified by GFP expression to determine log10 reduction. Remaining material was passaged on Vero cells to confirm absence of residual infectious virus. Input virus titers of 6.6–8.0 log10 per assay were completely inactivated by each disinfectant within 1–5 min contact time. The rapid and substantial inactivation of LASV suggests the utility of these microbicides for mitigating spread of infectious virus during Lassa fever outbreaks. [ABSTRACT FROM AUTHOR]

Objectives: To determine the prevalence of postoperative pain after endodontic treatment using low (LC) and high (HC) concentrations of sodium hypochlorite (NaOCl). Materials and methods: Six databases and the grey literature were searched to identify randomized clinical trials that evaluated postoperative pain after endodontic treatment using NaOCl. NaOCl concentrations were dichotomized into 'LC' (0.5% to 3%) and 'HC' (≥ 5%) and a proportion meta-analysis was applied to determine the postoperative pain prevalence: overall and according to pain intensity and postoperative time. The prevalence of patients using pain control medication was also determined. A significance level of 5% and a random effect model were applied for data analysis. Between-study heterogeneity was assessed by I2 index. Risk of bias (RoB) was assessed using the Cochrane Risk-of-Bias 2.0 tool. The certainty of evidence was assessed using the GRADE approach. Results: Ten studies were included in the review and eight in the meta-analysis. The overall prevalence of postoperative pain was 45% in LC and 39% in HC. The prevalence of pain in LC and HC after 24 h was 25% and 40%, respectively. After 48 h, the prevalence decreased to 10% in LC and 25% in HC. 'Absent pain' was the most prevalent score. The prevalence of patients who used medication was 9% in LC and 15% in HC. Three studies were classified as 'high RoB', five as 'low RoB', and two as 'some concerns'. The certainty of evidence was very low. Conclusions: The overall prevalence of postoperative pain after endodontic treatment using LC and HC of NaOCl was 45% and 39%, respectively. Clinical relevance: Postoperative pain is common after endodontic treatment using NaOCl, but tends to decrease over time. [ABSTRACT FROM AUTHOR]

With the increased use of microplastics and antibiotics in modern society, a large number of microplastics and antibiotics are being found in natural and water treatment systems. In this paper, the effect of polypropylene (PP), polyethylene (PE), and polystyrene (PS) microplastics (MPs) on the chlorination of ciprofloxacin (CIP) and subsequent production of disinfection byproducts (DBPs) was investigated using sodium hypochlorite (NaClO) as the disinfectant and trichloromethane (CHCl3) and dichloroacetonitrile (DCAN) as typical carbon- and nitrogen-containing disinfection byproducts. Disinfection byproducts (DBPs) were investigated. The results showed that the mass concentrations of CHCl3 and DCAN generated after CIP chlorination were higher, reaching 160.1 μg/L and 2.5 μg/L, respectively, than those generated after the chlorination of microplastics (0.49~41 μg/L). Considering the effect of microplastics on the chlorination of ciprofloxacin to generate disinfection byproducts, it was found that the increase in the production of CHCl3 and DCAN was not significant and that production even tended to decrease. There was a slight contribution to the generation of CHCl3 with increasing microplastic concentration. There was almost no effect on DCAN, and the generation of DCAN was even inhibited. Increases in pH, NaClO dose, and chlorination time promoted the generation of CHCl3, but DCAN showed a decreasing trend due to its instability and easy decomposition. This study provides a theoretical basis for understanding the generation of disinfection byproducts in water sources contaminated by microplastics and antibiotics. [ABSTRACT FROM AUTHOR]

The aim of this research was to develop a chalcone-based endodontic irrigant for cleaning and disinfecting the root canal. Minimal inhibitory concentration (MIC) experiments in C. albicans and E. faecalis strains with different aminochalcones (AM) were carried out, and the compound that presented the best activity against both pathogens was chosen. The formulation of an endodontic irrigant was elaborated, tested in mono and dual specie biofilms. Disks were sterilized and then incubated with E. faecalis, C. albicans and E. faecalis and C. albicans mixed for 72 h for biofilm maturation. After contamination, samples were divided in 4 experimental groups and 2 positive control group as follows: Group1: Irrigant; Group2: Irrigant + AM-38; Group3: Chlorhexidine 2% (positive control) and, Group 4: 1.0% sodium hypochlorite (positive control). The samples were analyzed by CFU/ml count. The sample was taken to sonicador to remove the cells and then plated. The toxicity was determined in vitro with human gingival fibroblast cells (HGF) and in vivo using the Galleria mellonella model. Formulation showed antimicrobial activity, with MIC on C. albicans 15.6 and E. faecalis 7.8 µg/ml. Treatment with formulation in concentration 156 µg/ml significantly reduced mono or dual species biofilm formation and viability (p < 0.05). The results were significant against C. albicans and E. faecalis and did not show toxicity in cells and G. mellonella. In general, the formulation showed effective antibiofilm activity, significantly reducing microorganisms, opening paths in search of new endodontic irrigants. [ABSTRACT FROM AUTHOR]

Hydrodynamic cavitation (HC) was a kind of advanced oxidation mode. There were defects in the common HC devices, such as high energy consumption, low efficiency, and easy plugging. In order to effectively utilize HC, it was urgent to research new HC devices and used them together with other traditional water treatment methods. Ozone was widely used as a water treatment agent that does not produce harmful by-products. Sodium hypochlorite (NaClO) was efficient and cheap, but too much chlorine will be harmful to water. The combination of ozone and NaClO with the HC device of propeller orifice plate can improve the dissolution and utilization rate of ozone in wastewater, reduce the use of NaClO, and avoid the generation of residual chlorine. The degradation rate reached 99.9% when the mole ratio γ of NaClO to ammonia nitrogen (NH3-N) was 1.5 and the residual chlorine was near zero. As for the degradation rate of NH3-N or COD of actual river water and real wastewater after biological treatment, the ideal mole ratio γ was also 1.5 and the ideal O3 flow rates were 1.0 L/min. The combined method has been preliminarily applied to actual water treatment and was expected to be used in more and more scenarios. [ABSTRACT FROM AUTHOR]

COVID-19 has affected all aspects of human life so far. From the outset of the pandemic, preventing the spread of COVID-19 through the observance of health protocols, especially the use of sanitizers and disinfectants was given more attention. Despite the effectiveness of disinfection chemicals in controlling and preventing COVID-19, there are critical concerns about their adverse effects on human health. This study aims to assess the health effects of sanitizers and disinfectants on a global scale. A total of 91,056 participants from 154 countries participated in this cross-sectional study. Information on the use of sanitizers and disinfectants and health was collected using an electronic questionnaire, which was translated into 26 languages via web-based platforms. The findings of this study suggest that detergents, alcohol-based substances, and chlorinated compounds emerged as the most prevalent chemical agents compared to other sanitizers and disinfectants examined. Most frequently reported health issues include skin effects and respiratory effects. The Chi-square test showed a significant association between chlorinated compounds (sodium hypochlorite and per-chlorine) with all possible health effects under investigation (p-value <0.001). Examination of risk factors based on multivariate logistic regression analysis showed that alcohols and alcohols-based materials were associated with skin effects (OR, 1.98; 95%CI, 1.87–2.09), per-chlorine was associated with eye effects (OR, 1.83; 95%CI, 1.74–1.93), and highly likely with itching and throat irritation (OR, 2.00; 95%CI, 1.90–2.11). Furthermore, formaldehyde was associated with a higher prevalence of neurological effects (OR, 2.17; 95%CI, 1.92–2.44). Furthermore, formaldehyde was associated with a higher prevalence of neurological effects (OR, 2.17; 95%CI, 1.92–2.44). The use of sodium hypochlorite and per-chlorine also had a high chance of having respiratory effects. The findings of the current study suggest that health authorities need to implement more awareness programs about the side effects of using sanitizers and disinfectants during viral epidemics especially when they are used or overused. [ABSTRACT FROM AUTHOR]

This study is one of the first to investigate the recovery rate of high- and low-density microplastic particles (polyvinyl chloride and polypropylene) from wastewater treatment plant effluents or comparable technical facilities under nearly realistic experimental conditions. For this purpose, a method of continuous dosing of microplastic particles into an experimental flume for open-channel flow was developed. Subsequently, 12 samples were taken using volume-reduced sampling and the entire sample purification process including oxidative treatment (with hydrogen peroxide and sodium hypochlorite), density separation (with sodium polytungstate), and subsampling was carried out. Detection was conducted using automatic particle recognition and µ-Ramanspectroscopy. An average recovery rate of 27 ± 10% was determined for polypropylene microplastic particles (d = 53 ± 29 µm), decreasing with the particle size, and 78 ± 14% for polyvinyl chloride microplastic particles (d = 151 ± 37 µm). The results suggest that microplastic emissions from wastewater treatment plants are underestimated, particularly because the recovery rate of small microplastic particles < 50 µm is only 9%. [ABSTRACT FROM AUTHOR]

To investigate the corrosion behaviors and antibacterial effects of sodium hypochlorite (NaClO) and hydrogen peroxide silver ion (HPSI) disinfectants with different concentrations against dental unit waterlines and provide guidance and reference for the use of chemical disinfectants, polyurethane tubes were immersed in ultrapure water (control group), 0.1% NaClO, 0.5% NaClO, 1.0% NaClO, 2.5% HPSI, 5.0% HPSI, and 10% HPSI solutions for 6, 12, and 18 weeks. Contact angles and Fourier transform infrared spectra were detected. Surface morphologies were observed using scanning electron microscopy and antibacterial activity was evaluated using Gram-positive Staphylococcus aureus (S. aureus). The results showed that sodium hypochlorite and hydrogen peroxide silver ion disinfectants presented good antibacterial activity against S. aureus. However, sodium hypochlorite could cause serious damage to the water pipes where corrosion pits and cracks were observed, and increasing the concentration of sodium hypochlorite could accelerate the corrosion process. Hydrogen peroxide silver ion disinfectants had no obvious damage to the water pipes. Therefore, hydrogen peroxide silver ion disinfectants are recommended to use for controlling bacterial infection in dental unit waterlines which can reduce the damage to the water pipes. [ABSTRACT FROM AUTHOR]

Objectives: The impact of conservative instrumentation on the disinfection of root canals with different curvatures has not yet been determined. This ex vivo study aimed to evaluate and compare the effect of conservative instrumentation with TruNatomy (TN) and Rotate and a conventional rotary system, ProTaper Gold (PTG), on root canal disinfection during chemomechanical preparation of straight and curved canals. Materials and methods: Ninety mandibular molars with straight (n = 45) and curved (n = 45) mesiobuccal root canals were contaminated with polymicrobial clinical samples. Teeth were divided into three subgroups (n = 14) according to the file systems and the curvature. Canals were instrumented with TN, Rotate, and PTG, respectively. Sodium hypochlorite and EDTA were used as irrigants. Intracanal samples were taken before (S1) and after (S2) instrumentation. Six uninfected teeth were used as negative controls. The bacterial reduction between S1 and S2 was measured by ATP assay, flow cytometry, and culture methods. Kruskal–Wallis and ANOVA tests were followed by the Duncan post hoc test (p < 0.05). Results: Bacterial reduction percentages were similar for the three file systems in straight canals (p > 0.05). However, PTG showed a lower reduction percentage of intact membrane cells in flow cytometry than TN and Rotate (p = 0.036). For the curved canals, no significant differences were obtained (p > 0.05). Conclusion: Conservative instrumentation of straight and curved canals using TN and Rotate files resulted in similar bacterial reduction compared to PTG. Clinical relevance: The disinfection efficacy of conservative instrumentation is similar to conventional instrumentation in straight and curved root canals. [ABSTRACT FROM AUTHOR]

Brown algae contain a β-glucan called laminaran that exhibits various biological activities, such as immune-enhancing, anti-cancer, and antioxidant properties. The laminaran content in brown algae varies depending on species, habitat, and season. When developing a laminaran-containing functional food using brown algae or its extract, accurate quantitative methods to determine laminaran content in a variety of brown algae and foodstuffs are required. In this study, we examined the applicability of the existing sodium hypochlorite extracting and enzymatic digesting (SEED) assay for the determination of the laminaran content of the brown alga Eisenia bicyclis. The laminaran content of E. bicyclis could be determined using the SEED assay. Furthermore, we developed a rapid and concise acid extraction enzymatic method. This method can specifically extract total water-soluble β-glucan (laminaran) and selectively convert it to glucose. The generated glucose content was determined using the glucose oxidase/peroxidase method. The validation test using brown algae E. bicyclis and Sargassum horneri revealed that the acid extraction-enzymatic method is accurate, precise, and applicable to the determination of the laminaran content in these brown algae. Furthermore, developed method was also applicable to laminaran-added processed foods. [ABSTRACT FROM AUTHOR]

Context: Sodium hypochlorite, a gold standard for irrigation in endodontics, has disadvantages like toxicity and root dentin weakening. Alternatives derived from natural products are being explored. Aims: This systematic review was done to understand the clinical benefits of natural irrigants when compared with a standard irrigant, sodium hypochlorite. Settings and design registration: This systematic review was registered with PROSPERO (2018 CRD42018112837) Methods and material: This review was done in conformation to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA 2020) statement. In vivo studies using at least one natural irrigant and sodium hypochlorite (NaOCl) were included. Studies using them as medicaments were excluded. PubMed, Cochrane and SCOPUS were searched. RevMan tool for Risk of Bias 2 (RoB 2) and risk-of-bias tool to assess non-randomized studies of interventions (ROBINS-I) were used. GRADEpro was used to assess certainty of evidence. Results: Ten articles (6 RCTs and 4 clinical studies) on approximately 442 patients were included. Seven natural irrigants were evaluated clinically. Due to the heterogeneity, meta-analysis could not be conducted. Antimicrobial efficacy was found to be similar for castor oil, neem, garlic-lemon, noni, papaine and NaOCl. Neem, papaine-chloramine, neem-NaOCl and neem-CHX were superior, while propolis, miswak and garlic were inferior to NaOCl. Post-operative pain was less for neem. There was no significant difference between papaine-chloramine, garlic extract and sodium hypochlorite in clinical/radiographic success. Conclusions: The studied natural irrigants are not more efficacious than NaOCl. At the moment, they cannot replace NaOCl routinely and may only substitute in select cases. [ABSTRACT FROM AUTHOR]

This paper reports on developing a low cost but efficient paired emitter–detector diode (PEDD)-based photometer. The photometer consists of a white light-emitting diode (LED) as the emitter diode, an RGB LED as the detector diode, and a multimeter for recoding the signal. The developed PEDD-based photometer was utilized for the determination of liquid bleach adulteration in cow milk samples. N,N-Diethyl-p-phenylenediamine sulfate aqueous solution of pH 6 was used as a probe to monitor the presence of residual active chlorine in milk. The results showed that the developed method could be used to determine sodium hypochlorite in the concentration range of 0.5 to 20.0 ppm Cl2 with 0.14 and 0.46 ppm Cl2 limit of detection and limit of quantification, respectively. The intraday and interday precisions of the method at two concentration levels of 5.5 and 13.7 ppm Cl2 were 1.04% and 0.52%, and 1.81% and 1.02%, respectively. The recoveries of 114.2% and 106.9% were obtained for 5.5 and 13.7 ppm Cl2 concentrations levels, respectively. Real sample analyzes results showed that "maybe" liquid bleach adulteration in milk is the case for local distributors of raw milk. [ABSTRACT FROM AUTHOR]

The study reports on the oxidation of sulfur compounds by sodium hypochlorite over molybdenum-based amphiphilic catalysts. The conversion of dibenzothiophene (DBT) was investigated as a function of the catalyst composition and reaction conditions. When sodium hypochlorite was used in combination with the heptamolybdate-anion-containing amphiphilic catalyst, sulfur compounds were found to be effectively oxidized even at room temperature. Under optimum process conditions (an oxidant to sulfur molar ratio of 4 : 1, a catalyst concentration of 0.5 wt %, and an acetonitrile volume of 1 mL), 100% conversion of DBT to sulfone had already been achieved after ten min of oxidation. The addition of acetonitrile to the reaction mixture was found to minimize the aggregation of catalyst particles and enhance the process performance. The catalyst demonstrated sustained activity over five oxidation cycles without regeneration. [ABSTRACT FROM AUTHOR]

The problems caused by water pollution are increasingly serious, wastewater contains a lot of heavy metal ions, textile dyes, medicines, etc. However, most adsorption materials usually face problems such as inefficient recycling, high cost, and secondary pollution. As a natural polymer, cellulose has low cost, degradability and good biocompatibility. In this work, by changing the addition amount of sodium hypochlorite during 2,2,6,6-Tetramethylpiperidine-1-oxyl radical (TEMPO) oxidation, nanocellulose with different carboxyl content could be prepared, which is expected to be a good high-efficiency cationic adsorbent due to its rich in hydroxyl groups on the surface and negatively charged. Then the calcium chloride solution was used as the cross-linking agent to prepare TEMPO-oxidized cellulose nanofibril beads (TOCNB) by the dropping solidification method. As the content of carboxyl groups increases, the Zeta potential value of the nanocellulose dispersion became increasingly negative. The nanocellulose beads all presented a good three-dimensional network porous structure. With the increase of carboxyl group content, the specific surface area increases from 173 to 367 m2 g−1, and the adsorption capacity for methylene blue (MB) also gradually strengthened. The saturated adsorption capacity of TOCNB on MB was calculated as high as 925.93 mg g−1. The nanocellulose bead was a cationic adsorbent with highly efficient adsorption and adjustable specific surface area, and the preparation method was simple, fast, efficient and green. [ABSTRACT FROM AUTHOR]

Cultivation of microalgae or/and cyanobacteria in nutrient-rich wastewaters offers an opportunity for enhancing sustainability of tertiary wastewater treatment processes via resources/energy recovery/production, mitigation of emitted GHGs and provision of added value products. However, maintaining a monoculture in wastewater-media constitutes a significant challenge to be addressed. In this regard, the present work assesses the efficiency of the low-cost wastewater substrate disinfection techniques of filtration, use of NaClO, H2O2 or Fe(VI), as a preliminary treatment stage upstream a cyanobacteria cultivation photobioreactor. The growth rate of cyanobacterium Synechococcus elongatus PCC 7942, and nitrate and phosphate removal rates, were experimentally assessed in cultivation setups with biologically treated dairy wastewater that had been subjected to a single or a synergetic couple of disinfection techniques. The results showed that filter thickness has a greater effect on disinfection efficiency than filter pore size. Furthermore, the disinfection efficiency of Fe(VI), which was produced on-site by electrosynthesis via a Fe0/Fe0 cell, was greater than that of NaClO and H2O2. Filtration at ≤ 1.2-μm pore size coupled with chemical disinfection led to unhindered Synechococcus elongatus PCC 7942 growth and efficient nitrate and phosphate removal rates, at dosages, in terms of Concentreation-Time (CT) product, of CT ≥ 270 mg min L−1 for NaClO and CT ≥ 157 mg min L−1 for Fe(VI). The coagulation action of Fe(III) species that result from Fe(VI) reduction and the oxidation action of Fe(VI) can assist in turbidity, organic compounds and phosphorous removal from wastewater media. Moreover, the residual iron species can assist in Synechococcus elongatus PCC 7942 harvesting and may enhance photosynthesis rate by increasing light transfer efficiency. Thus, a filtration configuration coupled with chemical disinfection, preferably using ferrates, downstream of sedimentation tank of a secondary biological wastewater treatment stage is proposed as a necessary, efficient and low-cost disinfection technique for full-scale scale implementation of cyanobacteria cultivation as tertiary wastewater processes. [ABSTRACT FROM AUTHOR]

The presented work was focused on investigating the effects of sodium-hypochlorite (NaOCl) and hypochlorous-acid (HOCl) solutions on the dynamic cyclic fatigue resistance of WaveOneGold (WOG), K3XF and Hyflex-EDM (HEDM) nickel-titanium (Ni-Ti) instruments. A total of 141 Ni-Ti instruments were included in the study, 45 of each file for cyclic fatigue testing and two for metallurgical analysis. The NiTi instruments were rotated in an artificial canal that was immersed in three different solutions [2.5% NaOCl, HOCl or distilled water (DW)] at body temperature until fracture occurred and the time to fracture (TtF) in seconds was recorded. Fractured and unused files were analysed by scanning-electron-microscopy (SEM) with energy-dispersive X-ray spectrometry (EDS), X-ray diffraction (XRD), and a microhardness tester. The mean data were analyzed statistically using Kruskal-Wallis, and post hoc Mann-Whitney-U test. The TtF of the HEDM was statistically significantly higher than that of WOG and K3XF for all solutions. It was found that 2.5% NaOCl and HOCl solutions reduced the TtF of the WOG, but had no significant effect on the K3XF and HEDM. By EDS analysis, it was determined that titanium-oxide compounds were formed on the file surfaces at most in 2.5% NaOCl solution. The highest hardness value was K3XF, and the lowest hardness value belonged to the HEDM instrument. The HOCl solution can be used as an alternative irrigation solution as it is less corrosive to the instruments compared to than NaOCl solution. [ABSTRACT FROM AUTHOR]

Objectives: We performed this network meta-analysis to determine the comparative efficacy of formocresol (FC), ferric sulfate (FS), sodium hypochlorite (NaOCl), calcium hydroxide (CH), mineral trioxide aggregate (MTA), biodentine, and laser for pulpotomy of molar teeth. Materials and methods: An updated search was conducted in PubMed, Embase, and the Cochrane Library to identify relevant randomized controlled trials (RCTs) published before October 30, 2022, after screening previous meta-analyses. The Cochrane risk of bias assessment tool was used to appraise the methodological quality of included studies. Clinical and radiographic success rates were assessed as outcomes. Random network meta-analysis was performed by using STATA software (version 14.0) with "network" command. Results: A total of 43 RCTs were included. Network meta-analysis indicated that CH was inferior to other medicaments and techniques in all outcomes, and MTA and biodentine was better than FC, FS, and NaOCl in terms of clinical and radiographic success rates. Results of ranking probabilities suggested that MTA ranked first in all outcomes except for clinical success at both 6 months. Conclusions: Our results suggested that MTA was associated with significant improvement in both clinical and radiographic success than other pulpotomy medicaments and techniques, with the highest probability of being the optimal option. Clinical relevance: The current network meta-analysis determined the comparative efficacy and safety of 7 common pulpotomy medicaments in molar pulpotomy, including FC, FS, NaOCl, CH, MTA, biodentine, and laser, and the pooled results revealed comparable efficacy in clinical and radiographic success rates at 6 and 12 months between FC, FS, and NaOCl in primary molars pulpotomies. However, MTA, biodentine and laser may have more advantages than other pulpotomy medicaments for clinical and radiographic success. Therefore, in clinical practice, practitioners should select MTA, biodentine, or laser as pulpotomy medicaments in molar pulpotomy. [ABSTRACT FROM AUTHOR]

This study aimed to compare the antibacterial effects of different agitation devices on single- and multispecies biofilms in dentin canals using confocal laser scanning microscopy (CLSM). Dentin blocks were prepared from human root dentin. Enterococcus faecalis and multiple species were introduced into the dentinal tubules via centrifugation and incubation. Two infected dentin samples were placed at 8 and 16 mm in a customized model. Samples were randomly divided into eight groups according to the agitation device used: syringe needle irrigation, EndoActivator, passive ultrasonic irrigation (PUI), and EDDY, at 2.5% or 6% NaOCl concentrations. The samples were stained and observed using CLSM. Statistical analysis was performed using an independent sample t test and analysis of variance. Linear models were used to assess the joint impact of the experimental groups on the proportion of biofilms killed. No significant differences were observed between the killing rates of the single- and multispecies biofilms. Both concentrations of NaOCl significantly increased the percentage of dead bacteria compared with the control. Biofilms in dentin tubules was more effectively killed when NaOCl was agitated; however, the difference between PUI and EDDY was not significant. Significantly more bacteria were killed in dentin blocks placed at 8 mm than at 16 mm (p < 0.05). In conclusion, EDDY was as effective as PUI when combined with NaOCl. However, the apical portion, which had a low antimicrobial efficiency, remains a concern. Mechanical instrumentation is incapable of completely eradicating bacteria, and additional research is required to improve the efficacy of root canal disinfection. [ABSTRACT FROM AUTHOR]

Background: Chemical–mechanical caries removal (CMCR) products are in constant evolution and were recommended during the COVID-19 pandemic as substitutes for conventional caries removal. Aim: Characterize the worldwide scientific literature about CMCR products, over the years, by means of a critical review. Design: Electronic search was performed on Medline/PubMed, Scopus, Web of Science, Cochrane Library, Lilacs, and Embase up to November 2020. Year, journal, country of authors, and type of study were the data extracted from the retrieved studies. Additional data of the clinical studies and systematic reviews were investigated. Results: 2221 records were identified, 397 selected. 2011–2020 period concentrates higher number of publications (n = 169), in the Journal of Dental Research (n = 51), developed in Brazil (n = 45) and India (n = 44). Most studies were in vitro (n = 211) and clinical trials (n = 101). Carisolv™ (n = 48) and Papacarie Duo Gel™ (n = 33) were the most used products, prescript in isolated usage (n = 101), and compared with drills (n = 77). CMCR were more studied in primary teeth (n = 78), receiving glass ionomer cement (GIC) (n = 51) as restorative material. The most evaluated outcomes were time spent (n = 48) and pain (n = 41). Clinical application of CMCR takes more time than other techniques, but can also reduce patient anxiety, pain, and need for anesthesia. Conclusion: In vitro and clinical studies with CMCR products have been increasing, mostly carried out in developing countries, evaluating Carisolv™ and Papacarie Duo Gel™. Clinical studies tend to evaluate the time spent and pain compared to drills for removing caries in primary teeth, posteriorly restored with GIC. CMCR clinical application reduces anxiety, pain, and need for anesthesia, despite increase treatments' time. [ABSTRACT FROM AUTHOR]

In this study, functional coatings with N-halamine structure were formed on cotton fabrics by dopamine (DA) auto-deposition and DA/Polyethyleneimine (PEI) covalent co-deposition, respectively. SEM、UV-Vis and XPS had confirmed the deposition of DA and DA/ polydopamine (PDA) on the cotton fabrics. When the mass ratio of DA/PEI was 1:1.5, a uniform functional coating was formed. XRD had indicated that the coating and the oxidative sodium hypochlorite solution did not affect the crystal structure of cellulose. The DA/PEI co-deposited modified cotton fabric had excellent antibacterial property after chlorination, and the inactivation rate against E coli and S aureus could reach 100% with a contact time of 30 min. In vitro cell cytocompatibility studies demonstrated that the DA/PEI co-deposited modified cotton fabric has good biocompatibility. The functional coating on the cotton fabric remained stable after 50 washing cycles. The UPF values and the wrinkle recovery angle (WRA) tests showed that the DA/PEI co-deposited coating imparted great durable press and UV protective properties to the cotton fabric. The breaking strength loss rate of the modified cotton fabrics after chlorination was about 20%, which had little effect on the wearing property. [ABSTRACT FROM AUTHOR]

The forecast analysis of the exposure to the contamination risk in a water distribution network requires increasing the quality of the applied input/outputs modeling. This need involves using non-traditional models responding to the increasingly high computation requirements. In this scenario, the Cellular Automata paradigm represents a new frontier with considerable potential. Specifically, this paper describes the Eulerian Water quAlity Modeling—Cellular Automata (EWAM-CA) model, aimed at simulating the sodium hypochlorite (chlorine) injection, transport, and reaction phase in a medium-sized drinking water network. The EWAM-CA accuracy was compared with the Epanet software on a Fossolo water network, in Bologna town (Italy), considering a constant and an impulsive input respectively. Due to CA's intrinsic aptitude for parallel computing, a parallel version of EWAM-CA was developed. Moreover, using the capability of the cellular automata to manage the modeling asynchronously, improving the computational efficiency, we propose a novel approach based on activation/deactivation asynchronous rules, avoiding unnecessary calculations in nodes or pipes where no pollution occurs. The different EWAM-CA versions were compared for the case study, and the parallel EWAM-CA approach coupled with asynchronous functionality significantly improved computational performance. [ABSTRACT FROM AUTHOR]

The insect egg surface can serve as a vehicle for vertical symbiont transmission from the maternal parent to its offspring. Hypochlorite and formaldehyde are two common disinfectants used for insect egg surface sterilization. Here, we explored the intestinal microecology and immune response profile of the silkworm Bombyx mori strain Dazao after disinfectant exposure by using high-throughput sequencing technology and real-time PCR analysis. After egg surface sterilization, no significant difference (P > 0.05) in overall body weight was observed among the control, sodium hypochlorite, and formaldehyde groups. 16S rRNA metagenomic sequencing revealed that the main abundant intestinal bacteria were Enterococcus, Burkholderia, Phenylobacterium, Ralstonia, Chitinophaga, Bradyrhizobium, Herbaspirillum, and two unclassified Bacteroidetes species. Egg surface sterilization evidently altered the composition and abundance of intestinal microbiota but did not significantly change its alpha diversity. The dysbiosis of intestinal microbiota resulted in the perturbation of the immune response profile of the silkworm intestine. Our findings reveal that hypochlorite has a blocking effect on the symbiont transmission compared with formaldehyde. More importantly, egg surface sterilization exerts substantial effects on the ecophysiological traits of insects. The present study contributes to the scientific and reasonable application of disinfectants for insect egg surface sterilization during industrial silk production and laboratory-scale insect rearing. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study is to assess the clinical and microbiological effects of a single subgingival administration of sodium hypochlorite gel (NaOCl) and compare it with 1% chlorhexidine (CHX) gel and a placebo gel following mechanical re-instrumentation during supportive periodontal therapy (SPT). Materials and methods: Sixty-two patients who had been treated for stage III–IV periodontitis and enrolled in SPT were included in the study based on following criteria: (1) active periodontal therapy completed at least 6 months before enrollment in the study, (2) presence of at least 4 non-adjacent sites with probing pocket depths (PPDs) ≥ 4 mm with bleeding on probing (BOP), or presence of 5–8 mm PPDs with or without BOP. All sites presenting PPD ≥ 4 mm and BOP at baseline and 3-, 6-, and 9-month follow-up timepoints were subgingivally re-instrumented with ultrasounds. Selected patients were randomly assigned into three groups and treated additionally with a single subgingival administration of NaOCl gel (group A); 1% CHX gel (group B); and placebo gel (group C). Main outcome variable was pocket closure at 12 months. Secondary outcome variables were changes in mean PPD, BOP, and clinical attachment level (CAL) along with changes in the numbers of the following five keystone bacterial pathogens: Aggregatibacter actinomycetemcomitans (A.a.), Porphyromonas gingivalis (P.g.), Prevotella intermedia (P.i.), Tannerella forsythia (T.f.), and Treponema denticola (T.d.). Results: At 12 months, pocket closure was obtained in 77.5% in the NaOCl treated sites. The reduction in PPD was higher with CHX than with NaOCl, although a statistically significant adjunctive effect for NaOCl (P = 0.028) was only observed in comparison with placebo only. Mean CAL improved in all groups and at all timepoints, compared to the baseline (P < 0.05). However, after 6 months, CAL gain was statistically significantly higher in the NaOCl treated group than following application of CHX (P = 0.0026). Conclusion: In SPT patients, a single adjunctive use of a NaOCl gel may provide benefits in controlling inflammation and residual pockets. Trial registration: ISRCTN Registry of Clinical Trials (ISRCTN11387188). Clinical relevance: A baseline single application of NaOCl gel in conjunction with mechanical debridement may achieve substantial pocket closure in patients enrolled in SPT; treatment time, cost, and applicability considerations should be taken into account when selecting this therapy. [ABSTRACT FROM AUTHOR]

The disinfection of root canal through minimally invasive access cavity remains questionable. This in vitro study compared the effectiveness of three disinfection measures including conventional irrigation, ultrasonic assisted irrigation, and erbium:yttrium-aluminum-garnet (Er:YAG) laser assisted irrigation through conventionally or minimally invasive access. Sixty-six extracted maxillary first molars were randomly divided into group 1 conventionally invasive access group (CIA) and group 2 computer-guided minimally invasive access group (MIA). Each group was further randomly divided into three subgroups, (A) conventional irrigation (CI), (B) passive ultrasonic agitation (PUI), and (C) Er:YAG laser activated irrigation (LAI). Enterococcus faecalis (E. faecalis) infection model was established inside all root canals after instrumentation was performed up to ProTaper Universal F2. After various disinfection methods, microbial samples were collected from root canals by paper tip method and cultured, and colony forming units (CFU) values of each sample were calculated. Then the root canals were enlarged to the size of F3, after which dentin debris was collected from the F3 file. After dilution and culturing, the CFU value was calculated for each group. Two-way analysis of variance (ANOVA) was performed to test the interaction. The results revealed a significant antagonism (F = 3.394, P = 0.043). The bacterial CFU counts of group B and group C were significantly less than that of group A (P < 0.05), and there was no significant difference between group B and C (P > 0.05). Additionally, group 2A was better than group 1A (P < 0.05); there was no significant difference between group 1B and group 2B, group 1C and group 2C (P > 0.05). Comparison of the bacterial CFU counts in dentin debris after disinfection, the results revealed a significant antagonism (F = 7.224, P = 0.002), and group C had the least. The disinfection effect of Er:YAG laser or ultrasonic assisted computer-guided minimally invasive access is similar to conventionally invasive access, and Er:YAG laser is better than ultrasonic in removing bacteria from dentinal tubules and is easy to operate, which is more suitable for minimally invasive root canal treatment. [ABSTRACT FROM AUTHOR]

Texturization of diamond cut crystalline silicon wafer faces a great difficulty due to the presence of deep saw marks on all over the wafer surface, which limits the ultimate efficiency enhancement of solar cell. Conventional slurry cut silicon anisotropic texturization is carried out by saw damage removal step with NaOH aqueous solution followed by etching with potassium hydroxide (KOH)-isopropyl alcohol (IPA) but textural result is not satisfactory after adopting diamond cut silicon texturization in conventional way. The non-uniform pyramidal surface has been observed with noticeable spots. Surface texturization of diamond cut silicon wafer has been improved after introducing a new method. Adding little amount of sodium hypochlorite (NaClO) along with KOH-IPA solution and excluding the saw damage removal step creates better textural result in 20 min compared to conventional texturization method. Minimum reflectance is observed at 9.88%, whereas conventional method provides above 16% reflectance. Batch compatibility test also provides uniform texturization result up to batch 6, after which the pyramidal angle gets tilted to 4.07 degree resulting increase in reflectance to 12%. Optimizing the chemical solution exhibits excellent anisotropic etching, which eventually improves silicon nanograss solar cell performance. About 14% efficiency is found for conventional texturization in diamond cut wafers, while 18.5% efficiency with 72% yield is found for our proposed method. [ABSTRACT FROM AUTHOR]

Medical personal protective equipment (PPE) made from nonwoven thermoplastic fibers has been intensively used, resulting in a large amount of biohazardous waste. Sterilization is indispensable before recycling medical waste. The aim of this work is to evaluate the effects of the decontamination treatments and help properly recycle the PPE materials. The study investigated the effects of three disinfection treatments (NaClO, H2O2, and autoclave) on chemical composition, molecular weight, thermal properties, crystallinity, crystallization kinetics, and mechanical tension of three types of PPE (Gown #1, Gown #2, and Wrap) made of isotactic polypropylene fibers. The chemical compositions of the materials were not evidently affected by any of the treatments. However, the Mw of the polymers decreased about 2–7% after the treatments, although the changes were not statistically significant. The treatments barely affected the melting and crystallization temperatures and the maximum force at break, but they tended to elevate the thermal degradation temperatures. Although the treatments did not notably influence the crystallinities, crystallization rates and crystal growths were altered based on the Avrami model regression. Since the detected changes would not significantly affect polymer processing, the treated materials were suitable for recycling. Meanwhile, evident differences in the three types of raw materials were recorded. Their initial properties fluctuated notably, and they often behaved differently during the treatments, which could affect recycling operation. Recyclers should test and sort the raw materials to assure product quality. The results in this study provide fundamental data for recycling medical PPE to reduce its environmental footprint. [ABSTRACT FROM AUTHOR]