NaOCl Solution Research Articles

Evaluation of Nematicidal Potential of Plant Growth Promoting Rhizobacteria against Meloidogyne incognita

Root-knot nematodes have a wide host range, causing damage to many annual and perennial crops. More than 100 species of Meloidogyne are known in which M. incognita (Kofoid and White) Chitwood is one of the most common and important plant parasitic nematode in tropical and subtropical regions of the world including Pakistan. Therefore, the present study was planned to check the effect of PGPRs on juvenile mortality and egg hatching inhibition of M. incognita under lab conditions. Eggs were isolated from egg masses by using NaOCl solution. Rhizobacteria (Bacillus subtilis, Pseudomonas fluorescens, Azotobacter chroococcum, Azospirillum sp., Rhizobium leguminosarum) were multiplied on nutrient broth and kept overnight at 28 ± 2 °C in shaking incubator. Cell free culture filtrates were obtained in falcon tubes by centrifuging PGPRs @ 4000 RPM twice for 30 minutes. Two ml of toxins of each PGPR was poured into each 5cm-dia. petri plate and 100 microliters of egg suspension containing approximately 100 eggs were put in each petri plate. Similar experimental conditions and protocols were used for juveniles’ mortality. In this experiment, instead of eggs, 100 J2s contained in 100 microliters of juvenile suspension were put in each petri plate. The petri plates were placed in completely randomized design in incubator at 28 ± 2 °C with ten replicates. Petri dishes containing distilled water were kept under control. All the PGPRs caused larval mortality and inhibition in egg hatching with varying degrees. The maximum egg hatching was inhibited by Bacillus subtilis while Rhizobium leguminosarum was found the least effective. The other PGPRs i.e. Pseudomonas fluorescens, Azotobacter chroococcum, and Azospirillum sp. showed intermediate results.

Assessment of the Influence of Various Concentrations of Sodium Hypochlorite on Stem Cell Derived From Human Exfoliated Deciduous Teeth (SHED) Proliferation and Differentiation.

Objectives Previous research has established that sodium hypochlorite (NaOCl) has a detrimental effect on dental stem cell viability and maturation. However, a review of the literature revealed no study evaluating the response of NaOCl to the survival of stem cells derived from human exfoliated deciduous teeth (SHEDs). Hence, the aim of the present trial was to assess the influence of various dilutions of NaOCl on SHEDproliferation and differentiation. Materials and Methods The 5.25% NaOCl solutions at concentrations of 0.5, 0.1, 0.025, 0.0125, and 0.005 mg/ml were used to assess the response to SHEDproliferation and differentiation through methyl tetrazolium (MTT) assay, alkaline phosphatase (ALP) assay, and reverse transcription polymerase chain reaction gene expression analysis at various time point intervals. Results MTT assay showed that the viability of SHEDs decreased with an increase in the concentration of NaOCl and an increase in incubation time. The ALP activity decreased with an increase in the concentration of NaOCl up to 14 days of incubation. However, the ALP activity of all the test specimens further decreased after 14 days of incubation. The gene expression levels of osteocalcin, dentin sialophosphoprotein, and STRO-1 were statistically significant when compared to the control after one, three, and seven days of incubation. Conclusion Different doses of NaOCl other than 0.5 mg/ml revealed encouraging outcomes in terms of proliferation, long-term ALP functioning, and odontogenic differentiation potential when cultivated in SHEDs.

Effective decontamination and multiplication of Croton membranaceus in vitro

Abstract. Adukonu IA, Ayeh KO, Acheampong E. 2022. Effective decontamination and multiplication of Croton membranaceus in vitro. Cell Biol Dev 6: 68-81. Croton membranaceus Müll. Arg. is a useful herb with medicinal properties, and its leaves, roots, and bark are used to treat diverse ailments. However, the harvesting method by traditional medical practitioners without replacement exposes it to extinction. Therefore, the only means of propagating is by relatively slow use of seeds, and an alternative propagation method is needed for field establishment and nursery. Therefore, this study aims at determining an effective propagation by sterilization regime and subsequent in vitro regeneration using different explants; intact seeds, isolated embryos, coatless seeds, and nodal-cutting. The explants were decontaminated using double sterilization; the best was achieved by pre-treatment with 70% ethanol for 3 min before immersion in sodium hypochlorite (NaOCl). Intact seeds were effectively decontaminated by immersion in 15% NaOCl solution for 20 min, then by 10% NaOCl for 15 min. Conversely, coatless seeds were effectively decontaminated when isolated from intact seeds immersed in 20% NaOCl solution for 20 min and 15% NaOCl for 15 min. Further, embryos isolated from intact seeds were effectively decontaminated in 20% NaOCl for 15 min, then by 15% NaOCl for 10 min sequentially. These sterilization regimes successfully decontaminated 86% intact seeds, 100% isolated embryos, and 80% coatless seeds. Nodal-cutting explants were best decontaminated by immersion in 20% NaOCl solution for 15 min, followed by 15% NaOCl for 10 min sequentially without ethanol pre-treatment. This sterilization regime successfully decontaminated 100% of the nodal-cutting explants. However, the development of shoot explants varied in response to sterilization. Intact seeds did not develop into shoots, while isolated embryos, coatless seeds, and nodal-cutting explants developed into shoots independent of the sterilization regime. Shoot development was highest with the medium’s shoot-tip explants added with BAP, NAA, and GA3. Shoot multiplication was best achieved on an MS basal medium with 5.0 ?M BAP, 0.5 ?M NAA, and 5.0 ?M GA3 amendment.

Continuous Chelation Concept in Endodontics

Background:Continuous chelation can be defined as the concept of using a single mix of a weak chelator with NaOCL throughout the entire root canal preparation procedure without causing a reduction in the antimicrobial and proteolytic activity of NaOCL. Etidronic acid, also known as "1-Hydroxyethylidene-1, 1-Bisphosphonate" HEBP, or HEDP, is a soft biocompatible chelator utilized in direct combination with sodium hypochlorite to form an all-in-one deproteinizing, disinfecting, and chelating solution. It's the only chelator available as a certified commercial product, "Dual Rinse HEDP," approved for endodontic usage. This review aims to analyze and bring up-to-date data about the continuous chelation protocol using a combination of HEDP with sodium hypochlorite in endodontic irrigation. Data: only papers that were published electronically were searched within the review. Sources: “Google Scholar”,” PubMed” websites were used for searching data by using the following keywords: : Bisphosphonates, Continuous chelation, Dual rinse HEDP, Etidronate, HEBP. The most relevant papers related to the topic were chosen, specifically the original articles and clinical studies, including only English-language articles from 2005 to September 2022. Conclusion:Combining a weak chelator with NaOCL solution, a single irrigation solution mixture with soft tissue dissolving ability and antibacterial properties with chelating capability can be created, which can be considered a good alternative to the conventional irrigation protocol (sequential irrigation) with NaOCL followed by using a strong chelator such as EDTA. The obvious benefit is that only one solution is required for root canal cleansing and decontamination, also decreasing the time for irrigation and providing better conditioning of root canal walls for root-filling materials

First Report of Phytophthora inundata Associated with Decline and Death of Walnut (Juglans regia L.) in Italy.

Persian walnut (Juglans regia L.) is an important nut crop in Italy. In recent years, incidence of walnut decline and death has increased in many Italian commercial orchards. In early summer 2020, we observed a serious decline in approximately 5% of trees in a waterlogged area of a Veneto-region walnut orchard (J. regia, cv Lara). Symptoms included extensive foliar wilt and canopy decline associated with collar and root rot. Symptomatic tissues excised from larger roots of affected trees were surface disinfested for 1 min in a 1% NaOCl solution, rinsed for 5 min in sterile distilled water, and placed onto P5ARPH selective medium (Jeffers and Martin 1986). A Phytophthora-like organism was consistently isolated. Pure cultures were obtained by single-hyphal transfers onto potato dextrose agar (PDA). Isolates were identified as Phytophthora inundata based on morphological characteristics (Brasier et al. 2003), sequences of internal transcribed spacer (ITS) amplicons from universal primers ITS6 (Cooke et al. 2000) and ITS4 (White et al. 1990) and sequences of cytochrome c oxidase, subunit II (Cox II) from Fm75 and Fm78 primer pair (Martin and Tooley 2003). On carrot agar (CA), colonies had a characteristic stellate to broad lobed patterns. On this medium, optimal growth was at 28-30 °C (7,3 mm/day) and the upper temperature limit for mycelial growth was 37°C. Mycelial disks of isolate CREADC-Om306, grown on CA, were floated in Petri plates with soil extract solution and incubated under continuous fluorescent light at room temperature (25+/-2 °C). Within 48 to 72 h, sporangia were produced that were persistent, non-papillate, ovoid or ovoid-obpyriform, measuring 55.0 to 80.7 (length) x 41.3 to 65.2 (width) µm (averages 64.3+/-10.2 x 47.9+/-9.7 µm). Oospores and chlamydospores were absent. BLAST analysis of the amplicons from CREADC-Om306 revealed ITS sequences (854-bp; GenBank accession no. OK342200) and Cox II sequences (568-bp; GenBank accession no. OK349677) that shared 100% identity with published P. inundata sequences available in GenBank (acc. n. AF266791 for ITS; MT458994 for Cox II). Pathogenicity tests were conducted in the greenhouse on six 2-year-old walnut (J. regia, cv Lara) plants. Four of the plants were inoculated with CREADC-Om306 on two opposite sides of each plant's stem at 1-2 cm above soil line. A cork borer was used to remove a 5-mm disk of bark that was replaced by a 5-mm diameter mycelial plug from 10-day-old cultures of the pathogen on PDA. Two control plants were treated in the same way except the bark wounds were inoculated with sterile PDA plugs. Plants were kept in greenhouse at 24 ± 2°C. After 3 months, lesions had developed from all points of inoculation with. P. inundata (mean lesion length 55,25+/-6,22 mm) and the pathogen was reisolated from the lesion margins of all inoculated plants. The control plants remained symptomless and did not yield the pathogen. P. inundata is widely distributed across the world as a plant pathogen on several native as well as horticultural crops, especially in riparian or other areas subject to flooding or waterlogging. This report is the first to document P. inundata as a pathogen on Persian walnut and adds it to the diverse list of known susceptible perennial native, ornamental, and agricultural hosts of this organism. In addition to P. inundata, which belongs to the major Phytophthora ITS Clade 6, other members of the clade including P. megasperma (Belisario et al. 2012) and P. gonapodyides (Belisario et al. 2016) have been described as walnut pathogens.

Submerged photocatalytic membrane reactor utilizing ultrafiltration for ketoprofen removal from surface water

The investigations on the removal of a nonsteroidal anti-inflammatory drug – ketoprofen from a synthetic surface water containing humic acid (HA) in a new submerged photocatalytic membrane reactor (SPMR) coupling photocatalysis and ultrafiltration are presented. The treated water circulated between a feed tank equipped with an ultrafiltration membrane and a labyrinth flow photoreactor irradiated with UVA radiation. TiO2 suspended in the feed (0.5–1.5 g L−1) was used as a photocatalyst. A positive influence of aeration on ketoprofen decomposition was observed. The investigations revealed a 75% degradation of the drug (initial concentration of 10 mg L−1) after 5 h of the SPMR operation at 1 g TiO2 L−1 and 14 NL min−1 of air flow rate. The concentration of dissolved oxygen during aeration remained on a constant level, while in the absence of bubbling decreased by almost 40% during 5 h of the process. No improvement of mineralization in the presence of aeration was observed, which was attributed to a slow degradation of complex HA molecules and their desorption from the photocatalyst under the action of air bubbles. A positive effect of the bubbling on membrane fouling mitigation was proved. The permeate flux in the absence of aeration decreased by 35%, while in the case of air flow rate of 7 and 14 NL min−1 - by 20% only. The efficiency of membrane cleaning using NaOCl solution was dependent on operational parameters of the membrane in SPMR. In 5 subsequent cycles a complete flux recovery after the cleaning was obtained for the membrane operated at -0.05 bar.

Histological Investigation of the Cleaning Effectiveness of Different Biomechanic Processes of Isthmus in Lower Molars.

This study aimed to evaluate the efficacy of different instruments (Hyflex, ROTATE, and hand files) and irrigation methods (EndoUltra, EndoActivator, and side-perforated syringe) in the mesial root canal of a mandibular first molar with isthmuses. Sixty-three mandibular molar teeth with isthmus were selected using cone beam computed tomography (CBCT) images. The root canals were instrumented with Hyflex, ROTATE, or hand files (21 of each) and three of each as control group and the specimens were embedded in silicone blocks. Final irrigation was performed with the perforated syringe or ultrasonic (EndoUltra) or sonic irrigation (EndoActivator). All canals were irrigated using 5.25% NaOCl solution (15 mL). Then, the roots were stained with hematoxylin-eosin, and specimens were sliced for histologic evaluation. The isthmus regions (2.7, 3, 4.7, and 5 mm from the apex) were analyzed, and the percentage of debris was calculated. All data were statistically analyzed using one-way analysis of variance and Tukey's tests. Both Hyflex and ROTATE groups showed less debris compared with the hand instrument group (P < 0.05). When irrigation methods were compared, EndoUltra showed the least, followed by EndoActivator and perforated needle irrigation having the maximum debris (p < 0.05). When sections were compared, the maximum debris was found in the apical section and the least in the coronal section (p < 0.05). Although none of the methods cleaned the isthmus completely, nickel-titanium (NiTi) systems and ultrasonic and sonic systems removed more debris than the side-perforated needle syringe irrigation.

The green synthesis of oligo(azomethine)s based on p-anisidine and o-anisidine: reaction conditions, electrochemical and thermal properties

Schiff bases and their conjugated oligo(azomethine)s have been synthesized via condensation and oxidative polycondensation of o-anisidine (OA) with 2-hydroxy-1-naphthaldehyde (2-HNA) and p-anisidine (PA) with 4-hydroxy benzaldehyde (4-HBA), respectively. The oxidative polycondensation reaction conditions of 1-[(2-methoxyphenylimino)methyl]naphthalen-2-ol (1,2-MPIMN) and 4-[(4-methoxyphenylimino)methyl]phenol (4,4-MPIMP) were studied by oxidants such as air and aqueous solutions of H2O2 and NaOCl in different concentrations in an aqueous alkaline medium between 50 °C and 90 °C at different reaction times. The structures of polymers were confirmed by FT-IR, UV-Vis and 1H-13C-NMR measurements. The molecular weights and surface morphologies of oligomers were determined by size exclusion chromatography (SEC) and scanning electron microscopy (SEM), respectively. Electrochemical and thermal features of compounds were studied using UV-Vis spectroscopies, cycling voltammetry (CV), and TG-DTA. The mass losses values ​​of the 1,2-MPIMN, oligo(1,2-MPIMN), 4,4-MPIMP, and oligo(4,4-MPIMP) were calculated from the thermogravimetric curves as 98.00%, 53.52%, 69.00%, and 58.70%, respectively, at 1000 °C. The HOMO, LUMO levels, electrochemical (E’ g ), and optical band gap energies (Eg ) values of the compounds were calculated from CV and UV-Vis data. The E’ g values of 1,2-MPIMN, oligo(1,2-MPIMN), 4,4-MPIMP, and oligo(4,4-MPIMP) were found to be 2.64, 1.54, 2.31, and 2.16 eV, respectively. The electrical properties of monomers and oligomers were determined at room temperature.

Antimicrobial efficiency and cytocompatibility of different decontamination methods on titanium and zirconium surfaces.

The purpose of this study was to investigate the efficiency of different implant-decontamination methods regarding biofilm modification and potential cytotoxic effects. Therefore, the amount of biofilm reduction, cytocompatibility, and elementary surface alterations were evaluated after decontamination of titanium and zirconium surfaces. Titanium and zirconium disks were contaminated with a newly developed high-adherence biofilm consisting of six microbial species. Decontaminations were performed using titanium curette, stainless steel ultrasonic scaler (US), glycine (GPAP) and erythritol (EPAP) powder air-polishing, Er:YAG laser, 1% chlorhexidine (CHX), 10% povidone-iodine (PVI), 14% doxycycline (doxy), and 0.95% NaOCl solution. Microbiologic analysis was done using real-time qPCR. For assessment of cytocompatibility, a multiplex assay for the detection of cytotoxicity, viability, and apoptosis on human gingival fibroblasts was performed. X-ray photoelectron spectroscopy (XPS) was used to evaluate chemical alterations on implant surfaces. Compared with untreated control disks, only GPAP, EPAP, US, and Er:YAG laser significantly reduced rRNA counts (activity) on titanium and zirconium (p< .01), whereas NaOCl decreased rRNA count on titanium (p< .01). Genome count (bacterial presence) was significantly reduced by GPAP, EPAP, and US on zirconium only (p< .05). X-ray photoelectron spectroscopy analyses revealed relevant re-exposure of implant surface elements after GPAP, EPAP, and US treatment on both materials, however, not after Er:YAG laser application. Cytocompatibility was impaired by CHX, PVI, doxy, and NaOCl. CHX and PVI resulted in the lowest viability and doxy in the highest apoptosis. Within the limits of this in vitro study, air-polishing methods and ultrasonic device resulted in effective biofilm inactivation with surface re-exposure and favorable cytocompatibility on titanium and zirconium. Chemical agents, when applied on implant surfaces, may cause potential cytotoxic effects.

The Effect Of Surface Disinfections Of Gutta-Percha On Shear Bond Strength Of Three Root Canal Sealers

Aim: The purpose was to study the influence of disinfectant solutions on shear bond strength between gutta percha (GP) and different sealers.&#x0D; Materials and method: 90 GP samples were used. Glassionemer sealer group A (n=20), mineral trioxide aggregate( MTA) sealer group B (n=20), iroot sealer group C (n=20), control group (n=10) for each group. Treated the surface of GP for each group by two disinfectant solutions (NaOCL 2.5%, CHX 2%).Shear bond strength( S.B.S) test was calculate by digital universal testing machine.&#x0D; Results: iroot sealer (group C) with NaOCL solutions at (2.5%) increase shear bond which were significantly different P≤0.05 from CHX at (2%) and fresh control cones. glassionemer sealer (group A) gaive the lowest measured.&#x0D; Conclusions: NaOCL solutions at 2.5% left a many pitting investigated on the GP surface. Thus it increased the bond with sealer. The quality of the surface texture and mechanical properties of GP were unaffected by a CHX solution of 2%. Therefore, they were considering as the safe disinfectant solutions for GP cones.

Color and physiochemical attributes of pointed gourd (Trichosanthes dioica Roxb.) influenced by modified atmosphere packaging and postharvest treatment during storage.

The efficiency of modified atmosphere packaging (MAP) in combination with postharvest treatment on the shelf-life, physiochemical attributes, color, and nutrition of pointed gourd was studied after storing in refrigerated (low temperature, LT) and ambient (room temperature, RT) conditions. Fresh pointed gourd fruits were dipped in NaOCl solution (0.01% w/v) and potassium metabisulphite (KMS) (0.05% w/v), blanched (100°C for 4 min), and then packed in perforated and non-perforated polythene and polypropylene packets of each type and brown paper bags as MAP before storing at LT and RT. Physiochemical attributes, color, and nutrition were measured until the marketable level of acceptance (up to shelf-life) after storage and compared with the untreated and unpacked samples (control). The results showed profound differences among the treatment variables in all the studied dependent parameters regarding the LT and RT storage conditions. Among the treatments, perforated and non-perforated polyethylene (NPE) and polypropylene (NPP) packaging performed well to retain a considerable amount of ascorbic acid, β-carotene, and greenish color (lower L*, high h*) in pointed gourd treated with NaOCl (0.01%) and KMS (0.05%) after storing at LT and RT. Furthermore, the principal component analysis suggested that five major quality attributes (L*, C*, h*, shelf-life, and ascorbic acid) were influenced remarkably in terms of non-perforated polyethylene packaging in combination with KMS treatment both in LT and RT storage conditions. However, perforated polythene and polypropylene in combination with NaOCl responded well in RT but only for the shortest storage life. Thus, a non-perforated polythene package with KMS treatment would be the best solution for retaining market quality acceptance with green color up to the extended shelf-life of 23 and 10 days, respectively, in the refrigerator (LT) and in ambient (RT) storage conditions.

First report of Coniella granati causing leaf spot of pomegranate (Punica granatum L.) in Hungary.

Pomegranate (Punica granatum L.), the hystoric fruit and ornamental crop native to Iran and North India is widely planted in the Mediterranean and became popular in the house gardens of northest parts of Europe (Fernandez et al. 2014) including Hungary. In August 2020 necrotic black lesions and serious defoliation were observed on 60% of 1-3 year old pomegranate trees (cv. Wonderful) in a horticultural nursery near Gödöllő, Hungary (47°36'00.9"N 19°21'26.5"E). Symptoms started as small irregular dark brown spots on the leaves, which later increased in size (2.6 ± 0.9 mm). Ultimately, the entire leaf turned yellow, defoliation resulted in damage on (6) - 8 - (15)% of the leaves. Then, black pycnidia with unicelled, elliptical to fusiform, colourless conidia (Avg. 50 conidia: 2.4 - (3.6) - 3.9 × 10.2 - (13,1) - 17.9 µm) developed on the surface. These morphological features matched those described earlier by Van Niekerk et al. (2004) and Alvarez et al. (2016) for C. granati. Conidia from pycnidia were directly transferred to potato dextrose agar (PDA) by sterile needle. The plates were incubated at 24°C in the dark. Light yellow colonies with whitish aerial mycelia and later black globose pycnidia were observed. Mass of conidia oozed from pycnidia after 15 days of incubation. Pathogenicity tests were carried out on 1-year-old potted P. granatum trees (cv. Wonderful) with 5 replicates in the greenhouse. Ten, randomly selected leaves were inoculated per plant. 7-mm mycelial plugs from the edge of 10-day-old colonies were placed directly on disinfested (2% NaOCl solution, than sterile distilled water) leaves. The plants were covered with plastic film for 3 days after inoculation (26±3°C and 87±3% relative humidity). Pathogenicity was also tested on nonwounded, surface-disinfested fruits by mycelial plugs in 3 × 3 replicates. Inoculated fruits were placed in large grass vessels for 15 days (24±2°C and 80±5% relative humidity). Uncolonized, sterile PDA plugs were used as controls in both cases. Dark brown legions developed after 9-12 days on the plants in the greenhouse. On pomegranate fruits, the fungus colonized the fruit after 7-8 days, followed by fruit rot. In some cases, after 2 weeks pycnidia developed on the skin surface. No decay were present on control leaves or fruits. The pathogen was reisolated from all infected tissues and identified as C. granati, thus fulfilling Koch's postulates. For molecular identification, total genomic DNA of the isolate was extracted from the growing margins of colonies on PDA and partial sequence of internal transcribed spacer (ITS) and translation elongation factor 1-alpha (tef1) were amplified by PCR using primers described by Alvarez et al. (2016). Sequence data of the Hungarian isolate of the ITS region (GenBank acc. no. MW581953) showed 99.8% identity (559 bp out of 560 bp) with C. granati sequences deposited in GeneBank (Acc. nos. MH860368, MH855389 and KX833582). Considering tef1 sequence of the Hungarian isolate (OM908764) obtained had complete identity with other published C. granati isolates (KX833676, KX833682). C. granati has been previously reported on pomegranate from Europe (Palou et al. 2010, Pollastro et al. 2016). Based on morphological and molecular studies, this is the first record of C. granati in Hungary. The economic importance of this disease in currently limited in Hungary due to pomegranate is rather an ornamental crop, however, the first cultivation trials have been already started. There is a risk that the spread of the pathogen began with the infected propagating material, as a result the disease may outbreak anywhere in the country.

Chlorine vs. Sodium Chloride Regeneration of Zeolite Column for Ammonium Removal from an Explosives Impacted Mining Wastewater

There has only been limited research on ammonium removal by zeolites followed by chlorine regeneration; these studies used batch tests and, in many cases, only dealt with single solute solutions as opposed to multi-component ones. To better simulate full-scale applications, this study used a continuous-flow ion exchange (IE) column system to assess the feasibility of chlorine regeneration of a zeolite IE column used for the removal of ammonium from synthetic explosives impacted mining wastewater (EIMWW). Multi-cycle column loading-regeneration tests were used to evaluate and compare the performance of a NaOCl (1000 ppm as free Cl2) solution with that of a standard salt regeneration solution (5% NaCl). In addition, the impact of two loading cycle durations was evaluated. After three operational cycles with 6 h loading phases, the TAN (total ammonia nitrogen) uptake after NaOCl regeneration was almost the same as that obtained with salt regeneration (0.21 meq/g vs. 0.21 meq/g). The zeolite with NaOCl regeneration showed a higher preference for TAN than with NaCl regeneration (Ca:TAN:K = 2.8:2.3:1 vs. 2.5:1.9:1 for the 6 h loading phase); however, the NaOCl regeneration took longer to complete. It was also found that effluent pH, total chlorine level, and free chlorine level during the chlorine regeneration were positively related, seemingly confirming that the ammonium is oxidized to nitrogen gas and producing hydrogen ions. Regardless of the regeneration solution, if one uses a two-column system, with one column online and the other offline, the shorter loading cycles (6 h) yield a substantially higher daily TAN removal rate.

Unveiling the Impacts of Sodium Hypochlorite on the Characteristics and Fouling Behaviors of Different Commercial Polyvinylidene Fluoride Hollow Fiber Membranes.

Sodium hypochlorite (NaOCl) is a commonly used cleaning agent for recovering membrane performance in membrane technologies. A thorough understanding of the impacts of NaOCl exposure on membrane properties and fouling behavior is important for optimizing chemical cleaning process and extending membrane lifespan. In this study, three commercial polyvinylidene fluoride (PVDF) hollow fiber ultrafiltration membranes (SMM-1010, MEMCOR® CS II and ZeeWeed 500) were used to systematically explore the effects of NaOCl dose and solution pH (8 and 10) on membrane properties. The results showed that membrane pores increased with exposure time prolonging, and more pores were observed at pH 8 aging condition. The amide group in the Fourier transformation infrared spectra was disappeared, while the carboxylic acid and succinimide groups were formed at pH 10 and pH 8 conditions, respectively. The hydrophilicity and pure water permeability (PWP) of SMM-1010 and MEMCOR® CS II membranes had insignificant changes during NaOCl aging process, whereas the hydrophilicity of ZeeWeed 500 membrane slightly decreased and its PWP increased by 1.4-fold. The antifouling properties of NaOCl-aged SMM-1010 and MEMCOR® CS II membranes were slightly improved, whereas the NaOCl-aged ZeeWeed 500 membrane showed severer flux decline with humic acid filtration. Our findings could provide guidance for practical chemical cleaning process optimization.

Influence of various class cleaning agents for prosthesis on Co–Cr alloy surface

Abstract Introduction Denture cleaners should not be harmful to dental prostheses elements, but immersions in cleaner solutions during a long time of using prosthesis may cause changes on Co–Cr alloy surfaces. There are five classes of denture cleaners: alkaline hypochlorites, alkaline peroxides, disinfectants, diluted acids, and enzymes. The aim of this work was to evaluate the influence of denture cleaners solutions on the surface properties of Co–Cr alloy. Materials and method Specimens cast from cobalt–chromium alloy were divided into eight groups: 1 – dry; 2 – ultrapure water; 3 – 20% wt/wt sodium; 4 – 20% chlorhexidine digluconate; 5 – Correga Tabs BioFormula; 6 – 20% wt/wt citric acid; 7 – 0.5% NaOCl; and 8 – 5.0% NaOCl. After immersion in 200 mL of cleaning agent solution at 45°C in 3 years, simulation of use, surface roughness, contact angle, surface free energy (SFE), and microscopic observation was performed. Results For citric acid and NaOCl, roughness (R a) raised clearly. These cleaning agents also caused R q, R v, R p, and R Sm to increase the most. The observed water contact angle after using denture cleaners, especially citric acid, and NaOCl decreases, and the values of SFE increase. Under a digital microscope, the harmful effect of citric acid and solutions of NaOCl was visible. Conclusions Diluted acids and alkaline hypochlorites in presented concentrations influence Co–Cr surface parameters like roughness and wettability. Other classes of denture cleaning agents do not affect surface roughness parameters which make them safer for the metallic components of removable partial dentures.

Evaluation of the Antibacterial Efficacy of QMix and AgNP Solutions in Root Canals of Primary Molars: An In-Vitro Study.

PurposeThe study aimed to evaluate QMix2in1 and silver nanoparticles (AgNPs) solution in eliminating Enterococcus faecalis (E. faecalis) bacteria within root canals of primary molars.Materials and methodsThe study sample consisted of 45 extracted primary molars, which were divided into three groups: Group 1 (control) NaOCl 5.25%, Group 2 (experimental) QMix2 in 1, and Group 3 (experimental) AgNPs 4000 ppm. The root canals were sterilized within an autoclave and then contaminated with E. faecalis bacteria. The root canals were irrigated for five minutes in a quantity of 3 ml using a 31-gauge irrigation needle, and then bacterial smears were taken.ResultsSodium hypochlorite, AgNPs, and QMix2in1 effectively reduced the bacterial count of Enterococcus within root canals of primary molars. There were statistical differences between all groups. QMix2in1 solution showed the greatest antibacterial efficacy, then NaOCl solution and AgNPs solution. ConclusionAll irrigation solutions used are effective in eliminating E. faecalis. QMix2in1 can be considered a good alternative to sodium hypochlorite in irrigation root canals of primary teeth.

Effects chemical disinfectants on surface roughness of conventional impression materials used for dental prosthetic procedures.

To compare the effects of disinfectants on surface roughness of the conventional impression materials following chemical disinfection procedures. Equal numbers (65 for each impression material) of disc-shaped (15 × 3 mm) samples (Total n = 195) were fabricated from polyvinyl siloxane (Zhermack Elite), polyether (3M Impregum Penta Soft), and vinyl siloxane ether (Kettenbach Identium Lightbody) impression materials. Each impression material group was divided into five subgroups including one control group (n = 13). Impression material samples were immersed in CaviCide for 3 min, Zeta 7 solution for 10 min, and 5.25% sodium hypochlorite solution for 3 and 10 min. Surface roughness (Ra) was measured using a profilometer (Mitutoyo-SJ 410, Mitutoyo Corp.). The study data were analyzed statistically. A statistically significant difference was found among impression materials and disinfectants in terms of surface roughness (P < 0.05). Polyvinyl siloxane material showed a lower Ra value compared to Polyether and VSE materials; while polyether material showed a significantly lower Ra value compared to VSE material. Ra values of the control group were significantly lower than the disinfectant group immersed in 5.25% NaOCl solution for 10 min. Among all impression materials, polyvinyl siloxane showed the least surface roughness following disinfection procedures. Impression disinfectants that are specially designed for disinfecting dental impressions resulted in less surface roughness in all impression materials. With this study, it was aimed to obtain a smooth and clear model for the production of correct and compatible prostheses in the laboratory while at the same time purifying the impressions from microorganisms.

Effects of traditional and novel proteolytic agents on tissue dissolution and dentine microhardness.

The study aimed to evaluate the tissue-dissolving ability of papain and bromelain with respect to that of sodium hypochlorite (NaOCl) at the temperatures of 25°C and 60°C. The study also assessed the effects of these proteolytic agents on radicular dentine microhardness. Warming NaOCl, papain and bromelain solutions resulted in significant tissue dissolution at all time intervals (p < 0.001). At 60°C, bromelain showed significantly higher tissue weight loss at every time interval when compared to NaOCl (p < 0.001). All of the three organic tissue dissolvents reduced the microhardness at 1hr when compared to their respective baseline values. The reduction in microhardness from the baseline reading was statistically significant only in the papain group at 30 min (p=0.018) and at 60 min (p=0.03) when compared to the control group. Hence it was concluded that bromelain exerted superior tissue dissolution action, especially when warmed, with minimal effect on dentine microhardness.

First Report of Dactylonectria alcacerensis, Dactylonectria macrodidyma, and Ilyonectria liriodendri Associated with Black Foot Disease of Grapevine in Argentina.

Black-foot is a fungal disease that affects young vines and planting material in the countries where grapevines are cultivated. During the 2018 grape-growing season, symptoms of reduced vigor, short internodes, leaf chlorosis, root rot and necrosis in the base of plants were observed in vines between 2 to 10 years old from 400 ha of vineyards of Mendoza and Salta regions. A total of 30% of the vineyards of cultivars Malbec, Cabernet Sauvignon and Aspirant Bouchet, and rootstocks 101-14 Millardet et de Grasset and 1103 Paulsen, had vines with disease symptoms. Vines had 15% disease incidence and 30% disease severity. These symptoms have been described as characteristic of black-foot, caused by "Cylindrocarpon"-like asexual morph fungi. Isolations were made from roots and basal part of 30 symptomatic plants. Fragments of advanced necrotic tissue were washed with running water, surface sterilized with 70% alcohol for 20 seconds, 2% NaOCl solution for 4 minutes and rinsed in sterile distilled water twice. These fragments were placed onto Potato Dextrose Agar (PDA) and incubated at 25°C in the dark for 10 days to isolate fungal pathogens. A total of 50 colonies resembling black-foot disease pathogens were subcultured onto fresh PDA in order to obtain single spore cultures. The isolates developed buff to cinnamon and dark brown, and felty mycelium. Colonies subcultured in synthetic nutrient agar (SNA) produced hyaline, cylindrical, straight and/or slightly curved with one to three septate (35.6 × 5.3 µm) macroconidia and abundant, hyaline, ellipsoidal and zero to one septate (12.5 × 6.0 µm) microconidia. Cultures and conidia morphological characteristics were similar to those of Ilyonectria or Dactylonectria genera (Cabral et al. 2012a; Lombard et al. 2014). DNA sequence analysis of the partial histone H3 gene was obtained for isolates INTA SC1 (I. liriodendri), INTA LC2 (D. alcacerensis) and INTA LC1 (D. macrodidyma) and deposited in GenBank (accession nos. OK338901, OK338900 and OK338899). The BLAST search was conducted against type specimens. Sequences showed high similarity (99% to 100%) to the sequences of Ilyonectria liriodendri (Halleen, Rego & Crous) Chaverri & Salgado (GenBank accession no. JF735509), Dactylonectria alcacerensis (A. Cabral, Oliveira & Crous) L. Lombard & Crous (GenBank accession no. JF735630) and Dactylonectria macrodidyma (Halleen, Schroers & Crous) L. Lombard & Crous (GenBank accession no. JF735647). Pathogenicity tests were conducted under greenhouse conditions on 1-year-old rooted canes cv Malbec using the three isolates. Ten rooted cuttings with pruned roots were immersed in a suspension of 106 conidia ml-1 of each isolate for 60 min (Cabral et al. 2012b) while control cuttings were immersed in sterile distilled water. Immediately they were planted in pots and kept in a greenhouse at a temperature between 25 to 30°C. Symptoms developed on all plants 4 months after inoculation and consisted in necrotic lesions of roots and in the base of the canes, with a reduction in root biomass. Plants did not develop aerial symptoms. All fungi were re-isolated only from necrotic lesions of root and base of inoculated canes, fulfilling Koch's postulates. No symptoms were observed on the control plants. To our knowledge, this is the first report of the species I. liriodendri, D. alcacerensis and D. macrodidyma associated with black-foot disease of grapevine in Argentina. Black-foot disease has a negative effect on the viability of planting material and young vines, and this report will assist with monitoring distribution of the disease as well as developing management recommendations to nurseries and grape growers in Argentina.

Effect of NaOCl and EDTA irrigating solutions on the cyclic fatigue resistance of EdgeTaper Platinum instruments

BackgroundTo compare the solution on the cyclic fatigue resistance of EdgeTaper Platinum (ETP) instruments with that of ProTaper Gold (PTG) in the presence of ethylenediaminetetraacetic acid (EDTA) or sodium hypochlorite (NaOCl) irrigating solutions.MethodsSixty PTG and 60 ETP instruments with the same size (#25) and taper (8%) were tested under 17% EDTA, 5.25% NaOCl, or distilled water (n = 20 each). Cyclic fatigue was tested using artificial canals that were milled in stainless steel blocks using a laser micromachining technique. The canals had a curvature angle of 60 and a curvature radius of 5 mm. The center of maximum curvature was set at 5 mm from the instrument tip. The block of artificial canals was stabilized inside a container that was filled with one of the tested solutions. The temperature was fixed at 37 °C with a tolerance limit of 1 °C. The number of cycles to fracture (NCF) was calculated and the fractured surfaces were examined using a scanning electron microscope. All statistical analyses were performed using SPSS software Version 20 (IBM-SPSS Inc., Chicago, IL) at a confidence level of 95%.ResultsETP showed higher NCF than PTG in any of the tested solutions (P < 0.05). Within each group, NaOCl drastically decreased the NCF compared to water and EDTA (P < 0.05) and changing the solution from distilled water to EDTA did not affect the fatigue resistance (P > 0.05).ConclusionsETP showed improved cyclic fatigue performance compared to PTG in all tested irrigating solutions. EDTA can be used in combination with NiTi instruments during canal instrumentation without compromising the cyclic fatigue resistance of PTG and ETP instruments. However, NaOCl drastically decreased the NCF.