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1.
J Indian Soc Pedod Prev Dent ; 38(2): 138-144, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32611859

RESUMO

Background: Use of silver diamine fluoride (SDF) after selective caries excavation can arrest the further progress of the carious lesion. Application of potassium iodide (KI) can reduce the staining due to SDF. Aim: The aim of the study was to evaluate the effect of the application of SDF, with and without acid etching and KI on the bond strength of resin-modified glass ionomer cement (RMGIC) to the carious dentin of primary teeth. Materials and Methods: In thisin vitro study, caries was induced on the occlusal surface by inoculating Streptococcus mutans strain in 36 extracted primary molars. The teeth were divided into four groups (n = 9), and the following treatments were done to the carious dentin prior to final restoration with RMGIC: Group I: 10% polyacrylic acid conditioner, Group II: 38% SDF, Group III: 37% phosphoric acid etchant followed by 38% SDF, and Group IV: 37% phosphoric acid etchant followed by 38% SDF and 10% potassium iodide solution. The microtensile bond strength was measured using universal testing machine. Failure modes were recorded using a scanning electron microscope. Results: There was no significant difference in microtensile bond strengths between the groups (P = 0.665), with the highest value seen in Group III. Conclusions: Application of SDF with or without acid etching and KI does not affect the bond strength of RMGIC to carious dentin of primary teeth.


Assuntos
Colagem Dentária , Cárie Dentária , Dentina , Adesivos Dentinários , Fluoretos Tópicos , Cimentos de Ionômeros de Vidro , Humanos , Teste de Materiais , Compostos de Amônio Quaternário , Cimentos de Resina , Compostos de Prata , Resistência à Tração , Dente Decíduo
2.
Pediatr Dent ; 42(3): 217-220, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32522326

RESUMO

Purpose: Early childhood caries remains a worldwide disease and often requires treatment under sedation or general anesthesia, with long waitlists. Silver diamine fluoride has been shown to arrest caries lesions. The purpose of this study was to determine whether silver diamine fluoride (SDF) application reduces emergency visits by waitlisted patients with early childhood caries (ECC). Methods: Waitlisted patients aged zero to 71 months with ECC who were treated with SDF were enrolled at the University of Florida's NCEF Pediatric Dental Center; their cumulative incidence of dental emergencies were compared with children who were waitlisted during the 16 months preceding the introduction of SDF. Data from patient records on demographics, dental visits, SDF placement, and caries arrest were abstracted. Bivariate analyses and multiple logistic regression modeling were performed. Results: Participants included 97 patients treated with SDF and 216 not treated with SDF. The cumulative incidence of dental emergencies was approximately 80 percent lower in the SDF group than in the comparison group (4.1 percent versus 17.6 percent; adjusted odds ratio equals 0.18; 95 percent confidence interval equals 0.06 to 0.54); 81 percent of SDF-treated surfaces were arrested at a follow-up visit. Conclusions: Silver diamine fluoride helps reduce emergency visits for children with early childhood caries while on treatment waitlists and confirms the effectiveness of SDF for caries arrest in primary teeth.


Assuntos
Cariostáticos , Cárie Dentária , Criança , Pré-Escolar , Emergências , Serviço Hospitalar de Emergência , Fluoretos Tópicos , Humanos , Lactente , Recém-Nascido , Compostos de Amônio Quaternário , Compostos de Prata
3.
Pediatr Dent ; 42(3): 221-225, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32522327

RESUMO

Purpose: The purpose of this study was to measure the shear bond strength (SBS) of glass ionomer cement (GIC) to artificial carious dentin with and without silver diamine fluoride (SDF) treatment. Methods: Permanent molars were sectioned and demineralized to create artificial carious lesions. In five groups, the demineralization of dentin, application of SDF, use of conditioner, and elapsed time between the placement of SDF and restoration were tested for differences in SBS using an UltraTester machine. Statistical analysis was done using the Kruskal-Wallis test and Tukey-Kramer multiple comparison tests. Results: The highest bond strength was found when GIC was placed on conditioned and demineralized dentin treated with SDF one week earlier. Treatment with SDF and use of conditioner did not statistically affect the SBS of GIC to demineralized dentin. Statistically significant increases in bond strength were found when one week elapsed between SDF application and GIC placement. The lowest bond strength was found with immediate GIC application onto SDF-treated demineralized dentin. Conclusions: These in vitro findings suggest that silver diamine fluoride treatment does not significantly affect the bond strength of glass ionomer cement to dentin lesions, and improved retention is obtained by allowing SDF solution to set for one week prior to GIC placement.


Assuntos
Colagem Dentária , Cárie Dentária , Dentina , Fluoretos Tópicos , Cimentos de Ionômeros de Vidro , Humanos , Teste de Materiais , Compostos de Amônio Quaternário , Resistência ao Cisalhamento , Compostos de Prata
4.
Bioresour Technol ; 312: 123564, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32506041

RESUMO

Biochar was prepared by rapid pyrolysis using pine nut shell as raw materials. Then cetyl trimethyl ammonium bromide modified magnetic biochar material (CTAB-MC) was obtained after modifying biochar by FeCl3 and cetyl trimethyl ammonium bromide. The CTAB-MC was characterized by SEM, FTIR, XRD and Magnetic analyses. Adsorptive property of the CTAB-MC for acid chrome blue K (AK) was studied. It was found that adsorption capacity was affected by solution pH, temperature, adsorption time, initial concentration and ionic strength. The CTAB-MC showed higher adsorption ability toward acid chrome blue K, which was up to 40% higher than that of MC. The experimental results showed that adsorption data of AK on the CTAB-MC well conformed to the Langmuir isotherm adsorption model and the pseudo-second order kinetic model. The CTAB-MC can be recycled three times. This work reveals that CTAB-MC is a promising adsorbent with broad application prospects.


Assuntos
Cetrimônio , Poluentes Químicos da Água , Adsorção , Compostos Azo , Brometos , Carvão Vegetal , Cinética , Fenômenos Magnéticos , Naftalenossulfonatos , Nozes , Compostos de Amônio Quaternário
5.
Pediatr Dent ; 42(3): 226-231, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32522328

RESUMO

Purpose: American Academy of Pediatric Dentistry guidelines recommend treatment of primary teeth with 38 percent silver diamine fluoride (SDF) as a noninvasive option to arrest active dental caries lesions. A significant outcome of SDF treatment are lesions that clinically harden and become more resistant to further decay. Many practicing dentists believe that this increased hardening is due to the reaction of silver and fluoride with carious dentin. The purpose of this study was to focus on the structural and chemical effects of silver diamine fluoride treatment on the native tooth. Methods: In SDF-treated cavitated dentin lesions in teeth subsequently extracted for orthodontic reasons, the authors observed continuous, filamentous silver densities formed in situ from 50 to 2,100 µm in length and 0.25 to 7.0 µm in diameter using high-resolution synchrotron X-ray microcomputer tomography and field emission scanning electron microscopy. These "microwires" fill voids in the lesion caused by disease and permeate through surrounding dentinal tubules. Results: Spectroscopy confirmed that the chemical composition of the observed microwires is predominantly silver. Conclusions: These observations suggest mechanistic explanations for the structural reinforcement of carious dentin in addition to remineralization. It is hypothesized that silver diamine fluoride may achieve its antimicrobial functions by biochemical interactions and through its inherent ability to integrate into the native tooth structure.


Assuntos
Cárie Dentária , Cariostáticos , Criança , Fluoretos Tópicos , Humanos , Compostos de Amônio Quaternário , Compostos de Prata
6.
Pharm Res ; 37(6): 104, 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32451736

RESUMO

The COVID-19 pandemic has highlighted an important role for drug repurposing. Quaternary ammonium compounds such as ammonium chloride, cetylpyridinium and miramistin represent widely accessible antiseptic molecules with well-known broad-spectrum antiviral activities and represent a repurposing opportunity as therapeutics against SARS-CoV-2.


Assuntos
Anti-Infecciosos Locais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/prevenção & controle , Reposicionamento de Medicamentos/métodos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Compostos de Amônio Quaternário/farmacologia , Humanos , Antissépticos Bucais , Sprays Nasais
7.
J Evid Based Dent Pract ; 20(1): 101422, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32381404

RESUMO

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: The effect of silver diamine fluoride in preventing caries in the primary dentition: a systematic review and meta-analysis. Oliveira BH, Rajendra A, Vietz-eenan A, Niederman R. Caries Res 2018;53(1):24-32. SOURCE OF FUNDING: Government: National Institute on Minority Health and Health Disparities of the National Institutes of Health under award no. R01MD011526 and U24MD006964, and Patient-Centered Outcomes Research Institute (PCORI) Award (PCS-1609-36824). The Teacher Training Program of the University of the State of Rio de Janeiro (Programa de Capacitação Docente da Universidade do Estado do Rio de Janeiro-PROCAD UERJ) also supported this work. TYPE OF STUDY/DESIGN: Systematic review with meta-analysis.


Assuntos
Cárie Dentária , Fluoretos , Cariostáticos , Fluoretos Tópicos , Humanos , Pintura , Compostos de Amônio Quaternário , Compostos de Prata , Dente Decíduo
8.
J Clin Pediatr Dent ; 44(2): 79-83, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271666

RESUMO

Objective: The study described the incidence of interproximal caries arrest following SDF and fluoride varnish application in the primary dentition. Study design: A retrospective analysis of dental records including radiographs was conducted for interproximal dental caries in pediatric patients treated with SDF applied with woven floss. Bitewing radiographs and ICCMS™ radiographic scoring criteria were used to assess caries depth in primary teeth at baseline and then at 12-month follow-up examination. Results: This study included 185 interproximal carious lesions in 131 patients treated with SDF. Mean baseline ICCMS™ score for all lesions was 1.50, with an average dmft of 2.9. The majority of carious lesions (n=155, 84.0%) showed radiographic evidence of non-progression at 12-month follow-up. There was no statistically significant difference in caries arrest among primary canines, primary first molars, and primary second molars (P=0.61). Furthermore, there was no statistically significant difference in caries arrest in patients with commercial insurance, Medicaid, or no insurance (P=0.27). Conclusions: SDF application with woven floss was associated with interproximal caries arrest in the primary dentition at 12-month follow-up in this sample of low caries risk children. Tooth type and insurance type were not associated with caries arrest.


Assuntos
Cárie Dentária , Cariostáticos , Criança , Fluoretos , Fluoretos Tópicos , Humanos , Pintura , Compostos de Amônio Quaternário , Estudos Retrospectivos , Compostos de Prata , Dente Decíduo
9.
J Adhes Dent ; 22(2): 161-172, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32322837

RESUMO

PURPOSE: To evaluate 1. the microtensile bond strength (µTBS) and in situ degree of conversion (DC) of adhesives applied using two bonding strategies after silver diamine fluoride (diamine) application on carious dentinal lesions, and 2. dentin etching patterns using SEM and energy dispersive x-ray spectroscopy. MATERIALS AND METHODS: Human molars were randomly divided into 12 experimental groups according to: 1. application of a silver diamine fluoride solution (carious dentinal lesion without silver diamine fluoride treatment [control], with 12% silver diamine fluoride [diamine 12%] or 38% silver diamine fluoride [diamine 38%]); 2. adhesives (Clearfil Universal Bond Quick [CUQ] and Scotchbond Universal [SBU]); 3. adhesive strategy (etch-and-rinse [ER] and self-etch [SE]). After restoration, the specimens were sectioned and submitted to µTBS testing. Sticks from each tooth were used for DC evaluation. To examine the changes induced by diamine before and after phosphoric acid treatment, SEM/EDX analysis was performed. Data from the µTBS and DC tests were analyzed using three-way ANOVA and Tukey's test (α = 0.05). RESULTS: Both concentrations of diamine resulted in a statistically significantly higher mean µTBS compared to the control (p < 0.0001). Diamine 38% showed a statistically significantly higher mean µTBS for both adhesives in SE mode compared to diamine 12% (p < 0.0001). The application of diamine to carious dentinal lesions did not significantly influence the mean DC values for either adhesive (p = 0.72). SBU showed a higher mean DC compared to CUQ (p = 0.03). After diamine treatment, there was an increase in the Ca peak intensity and the presence of residual silver ions mainly when diamine 38% was applied along with the SE approach. CONCLUSION: Independent of the adhesive application approach, the use of diamine may be a promising alternative to increase µTBS without jeopardizing the DC of the two adhesives in carious dentinal lesions.


Assuntos
Colagem Dentária , Cimentos Dentários , Dentina , Fluoretos Tópicos , Humanos , Compostos de Amônio Quaternário , Compostos de Prata , Resistência à Tração
10.
J Dent Child (Chic) ; 87(1): 4-11, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32151304

RESUMO

Purpose: Current national evidence-based recommendations for treatment of carious lesions include the use of 38 percent silver diamine fluoride (SDF). The purpose of this study was to learn parents' opinions of esthetic changes to their children's teeth following treatment with SDF.
Methods: Three-hundred nineteen parents who had previously consented to SDF for caries arrest or caries prevention were asked if their child received SDF, if they noticed changes because of SDF, and how "bothered" they were by the changes.
Results: Two-hundred ten parents reported their child received SDF in the past 12 months, of whom 76 percent were confirmed by Codes on Dental Procedures and Nomenclature (CDT): 115 children received SDF for caries arrest and 45 received topical fluoride (SDF) for prevention. Of all 210 who reported SDF, 30 percent described discoloration of their child's teeth or gingiva. On a scale of zero (not bothered at all by changes due to SDF) to 10 (very bothered), parents' average rating was 1.2 ipoints; the average within the caries arrest group was 1.7.
Conclusion: Dental treatment requires a shared decision between parents and professionals, and follow-up regarding new procedures is warranted. In this study, treatment with SDF was well accepted by most parents.


Assuntos
Cárie Dentária , Fluoretos Tópicos , Cariostáticos , Criança , Humanos , Pais , Satisfação Pessoal , Compostos de Amônio Quaternário , Compostos de Prata
11.
Community Dent Health ; 37(2): 143-149, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32212436

RESUMO

INTRODUCTION: Silver diamine fluoride (SDF) is used to prevent and arrest caries across the globe, particularly in the developing world. Whilst its use in the Western World is increasing, it is not yet routinely used in the United Kingdom, nor is it advocated by our national guidelines. OBJECTIVES: To explore the literature surrounding the use of SDF, and consider the reasons why SDF has not yet been widely adopted in the United Kingdom (UK). DISCUSSION: There is a growing evidence base for the use of SDF for the arrest and prevention of dental caries in the primary and permanent dentition. Potential side effects include staining of carious tooth structure, but in some cases this is acceptable to parents. There is no evidence for the cost effectiveness of SDF, although it may be a reasonably cost-effective option. CONCLUSION: SDF is perhaps not yet widely adopted in the UK due to a perceived parental concern about its staining effect. With a growing evidence base and reportedly higher efficacy than fluoride varnish for caries prevention and arrest, SDF has the potential to play an important role in managing dental disease in children and young people in both primary and secondary care.


Assuntos
Cárie Dentária , Adolescente , Cariostáticos , Criança , Fluoretos Tópicos , Humanos , Compostos de Amônio Quaternário , Compostos de Prata , Dente Decíduo , Reino Unido
12.
Environ Sci Process Impacts ; 22(2): 430-441, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32003378

RESUMO

Quaternary ammonium compounds (QACs) are widely applied as surfactants and biocides in cleaning and personal-care products. Because of incomplete removal during wastewater treatment, QACs are present in wastewater effluents, with which they are discharged into natural waters, where they accumulate in sediments. To assess the levels of QACs in aquatic environments, a liquid chromatography high-resolution mass spectrometry method using both target and suspect screening was developed. The water and sediment sample preparation, measurement, and data analysis workflow were optimized for 22 target compounds with a wide range of hydrophobicity, including ionic liquids that have potential use as solvents and QACs common in personal-care and sanitizing products. In wastewater effluents, average concentrations of all target and suspect QACs combined ranged from 0.4 µg L-1 to 6.6 µg L-1. Various homologs of benzylalkyldimethylammonium (BAC) and dialkyldimethylammonium (DADMAC) as well as the ionic liquid butylpyridinium and 15 suspect QACs were detected in at least one wastewater effluent sample. A spatial profile of sediment samples in a lake demonstrated potential inputs from both municipal wastewater effluent and agricultural sources for BACs. In sediment cores, two distinct trends of temporal QAC accumulation were observed. In lakes with large watersheds and mixed domestic and industrial wastewater sources (Lake Pepin and Duluth Harbor), peak concentrations of QACs were found at depths corresponding to deposition in the 1980s and decreases after this time are attributed to improved wastewater treatment and source control. In a smaller lake with predominantly domestic wastewater inputs (Lake Winona), concentrations of QACs increased slowly over time until today.


Assuntos
Líquidos Iônicos , Águas Residuárias , Poluentes Químicos da Água , Lagos , Compostos de Amônio Quaternário , Tensoativos
13.
Compend Contin Educ Dent ; 41(2): 84-89; quiz 90, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32017586

RESUMO

Silver has a long history of use in medicine and dentistry, as its powerful antimicrobial properties have benefited mankind immensely. Silver formulations can be traced back to Hippocrates, and silver nitrate has centuries of use in medicine, including being utilized intraorally since at least the early 1800s. In the past roughly 40 years, silver diammine fluoride (SDF) has been used in many parts of the world to treat tooth sensitivity and for chemical attenuation of dental caries lesions. SDF was more recently introduced in North America for treatment of dental sensitivity with widespread off-label use as a dental caries infection inhibitor. Accordingly, SDF has been the subject of much dental research and many published articles in dentistry. In addition to providing significant chemical interference of progression of caries infections, SDF has the ability to prevent initiation of the caries process. This article gives a brief history of silver use in medicine and dentistry and documents a simplified procedure to saturate contacting proximal surfaces of teeth with 38% SDF solution, followed by fluoride varnish coverage, to prevent caries lesions and intercept progression of existing caries infections.


Assuntos
Cárie Dentária , Amônia , Cariostáticos , Odontologia , Fluoretos , Fluoretos Tópicos , Humanos , América do Norte , Compostos de Amônio Quaternário , Compostos de Prata
14.
Int J Paediatr Dent ; 30(4): 514-522, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32012376

RESUMO

BACKGROUND: Parents of children with autism spectrum disorder (ASD) may have concerns with fluoride/silver content in silver diammine fluoride (SDF). AIM: To compare parental acceptance of SDF and dental fear between children with and without ASD. DESIGN: Three hundred parents were enrolled. Demographics, dental history, and dental fear were recorded. Subjects viewed an educational video and completed survey about SDF acceptance including the following: (a) overall acceptance, (b) aesthetic concerns by tooth location, (c) fluoride/silver concerns, and (d) its use as a general anaesthesia (GA) alternative. Descriptive, bivariate, and multivariate analyses were used. RESULTS: Significantly, more children with ASD had dental fear (ASD: 56% vs neurotypical: 26%). No differences in acceptance existed between the two groups overall or with respect to aesthetics, fluoride/silver content, or as an alternative to GA. Overall acceptance is >60%. Regardless of group, parents of older children were less likely to accept SDF as an alternative to GA (OR = 0.67 [95% CI: 0.50-0.90]). CONCLUSION: Parents of children with ASD had similar acceptance of SDF use compared to parents of neurotypical children. Children with ASD had higher levels of dental fear. Parents of younger children are more likely to accept SDF as an alternative to GA in both groups.


Assuntos
Transtorno do Espectro Autista , Cárie Dentária , Amônia , Cariostáticos , Criança , Fluoretos , Fluoretos Tópicos , Humanos , Pais , Compostos de Amônio Quaternário , Compostos de Prata
15.
Br Dent J ; 228(2): 75-81, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31980777

RESUMO

Silver diamine fluoride (SDF) is a clear, odourless liquid indicated for desensitisation of non-carious tooth lesions and molar incisor hypomineralisation. It is also useful for arresting carious lesions in adults and children who are high caries-risk and/or have difficult-to-control, progressing carious lesions, those who are unable to tolerate invasive treatment, elderly populations, and those who are medically compromised or have additional care and support needs. SDF may be used to manage lesions that are too extensive to restore but not associated with pain and/or infection. This can be important particularly where extractions might be contra-indicated for medical or behavioural reasons. This paper summarises the global evidence for the effectiveness and safety of SDF, describes what it is, its mechanisms of action and presents recommendations on how to use it. There are details on indications/contra-indications and risks/benefits to be considered in the use of SDF also discussion of how to approach SDF's side effect of black staining of carious tooth tissue. We give an example of an information sheet (Appendix S1, see online supplementary information) that may be used when discussing SDF with patients, particularly for primary teeth in children, but adaptable for the permanent dentition and for adults.


Assuntos
Cariostáticos , Cárie Dentária , Adulto , Idoso , Criança , Fluoretos Tópicos , Humanos , Compostos de Amônio Quaternário , Compostos de Prata
16.
Chemosphere ; 242: 125233, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896207

RESUMO

Acid/base/oxidant pretreatment influenced subsequent quaternary ammonium epoxide compounds modified carbon (QAE-AC) and hence PFOA and nitrate removal. This work discerned that the most favorable QAE-AC protocol for PFOA removal was achieved when the wood carbon pretreated with HNO3 to adjust the carbon's slurry pH to 4.77, and tailored with the QUAB188. For nitrate removal, the most favorable when the carbon was pretreated with NaOH to raise the carbon's slurry pH to 9.34, and then loaded with the QUAB360. Based on experimentally results and molecular model, we found that pore volume, phenolic groups and the surface charge were the main factors affecting the PFOA removal, while the only factor affecting nitrate removal was surface charge. The QUAB's epoxide functionalities have cross-linked with phenolics along the activated carbon's graphene edge sites. QAE is preferentially reacted with the phenolic in the micropores and mesopores of carbon, and some QAE molecules form new "pore-like structures" outside the pores with the graphene planes or other QAE molecules. This pore-like structure hosted adsorption capacity by the quaternary ammonium. The favorable PFOA adsorption sites were in smaller mesopores via both hydrophobic interaction and electrostatic interaction; and nitrate sorption was occurring in the smaller micropores via anion exchange. Therefore, it can be considered that QAE-AC can simultaneously adsorb PFOA and nitrate in water.


Assuntos
Caprilatos/química , Fluorcarbonetos/química , Modelos Químicos , Nitratos/química , Compostos de Amônio Quaternário/química , Poluentes Químicos da Água/química , Adsorção , Compostos de Amônio/química , Ânions , Carvão Vegetal/química , Compostos de Epóxi , Oxidantes , Água
17.
Water Res ; 171: 115468, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31926373

RESUMO

Anaerobic ammonium oxidizing (anammox) bacteria can directly convert ammonium and nitrite to nitrogen gas anaerobically and were responsible for a substantial part of the fixed nitrogen loss and re-oxidation of nitrite to nitrate in freshwater and marine ecosystems. Although a wide variety of studies have been undertaken to investigate the abundance and biodiversity of anammox bacteria so far, ecological niche differentiation of anammox bacteria is still not fully understood. To assess their growth behavior and consequent population dynamics at a given environment, the Monod model is often used. Here, we summarize the Monod kinetic parameters such as the maximum specific growth rate (µmax) and the half-saturation constant for nitrite (KNO2-) and ammonium (KNH4+) of five known candidatus genera of anammox bacteria. We also discuss potential pivotal environmental factors and metabolic flexibility that influence the community compositions of anammox bacteria. Particularly biodiversity of the genus "Scalindua" might have been largely underestimated. Several anammox bacteria have been successfully enriched from various source of biomass. We reevaluate their enrichment methods and culture medium compositions to gain a clue of niche differentiation of anammox bacteria. Furthermore, we formulate the current issues that must be addressed. Overall this review re-emphasizes the importance of enrichment cultures (preferably pure cultures), physiological characterization and direct microbial competition studies using enrichment cultures in laboratories.


Assuntos
Compostos de Amônio , Ecossistema , Anaerobiose , Bactérias , Bactérias Anaeróbias , Biodiversidade , Nitritos , Oxirredução , Compostos de Amônio Quaternário , RNA Ribossômico 16S
18.
PLoS One ; 15(1): e0227891, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978077

RESUMO

For the induction of antigen-specific T-cell responses by vaccination, an appropriate immune adjuvant is required. Vaccine adjuvants generally provide two functions, namely, immune potentiator and delivery, and many adjuvants that can efficiently induce T-cell responses are known to have the combination of these two functions. In this study, we explored a cationic lipid DOTAP-based adjuvant. We found that the microfluidic preparation of DOTAP nanoparticles induced stronger CD4+ and CD8+ T-cell responses than liposomal DOTAP. The further addition of Type-A CpG D35 in DOTAP nanoparticles increased the induction of T-cell responses, particularly in CD4+ T cells. Further investigations revealed that the size of DOTAP nanoparticles, prepared buffer conditions, and physicochemical interaction with vaccine antigen are important factors for the efficient induction of T-cell responses with a relatively small antigen dose. These results suggested that microfluidic-prepared DOTAP nanoparticles plus D35 are a promising adjuvant for a vaccine that induces therapeutic T-cell responses for treating cancer and infectious diseases.


Assuntos
Adjuvantes Imunológicos/farmacologia , Ácidos Graxos Monoinsaturados/farmacologia , Imunidade Celular/efeitos dos fármacos , Compostos de Amônio Quaternário/farmacologia , Vacinas/farmacologia , Adjuvantes Imunológicos/química , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Humanos , Imunidade Celular/imunologia , Lipossomos/farmacologia , Camundongos , Microfluídica , Nanopartículas/química , Vacinas/química
19.
Carbohydr Polym ; 230: 115605, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887900

RESUMO

Chitin is the second most abundant renewable polymer on earth, and its deacetylated derivative, chitosan, is a highly useful biopolymer. This work studied for the first time the application of ionic liquid (IL) tetrabutylammonium hydroxide ([TBA][OH]) and chitin deacetylase from Rhodococcus equi CGMCC14861 (ReCDA) for the efficient conversion of chitin into chitosan at room temperature. Results confirmed that chitin had good solubility in 18 wt% aqueous [TBA][OH] solution at 80 ℃. In addition, efficient chitin deactylation was observed with high concentrations of [TBA][OH] exceeding 12 wt% and showing potential application in chitin conversion. ReCDA activity on chitin was activated by [TBA][OH] pretreatment. Sequential and simultaneous strategies were also compared, and the results showed that the simultaneous one-pot deacetylation provided the highest acetic acid yield of 3.78 mg/g chitin powder after 24 h. This study serves as a guide for the dissolution and deacetylation of chitin to produce high value-added chitosan products.


Assuntos
Quitina/química , Recuperação e Remediação Ambiental/métodos , Líquidos Iônicos/química , Compostos de Amônio Quaternário/química , Ácido Acético/química , Acetilação , Biocatálise , Hidrólise
20.
Int J Phytoremediation ; 22(8): 819-826, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31920091

RESUMO

Water pollution due to agricultural and industrial processes may cause adverse biological effects in aquatic organisms such as fishes. The removal of brilliant green (BG) dye from aqueous solution using seaweed Sargassum wightii was carried out. Further, it aimed to evaluate the exposure of BG dye activity on hematological, plasma biochemical, enzymological activities and histopathology of Indian major carp, Labeo rohita as a biomarker. High mortality rate (T2 65%) in the fishes exposed to untreated BG dye shows the toxic nature of the dye. Whereas fishes grown in treated BG dye showed less mortality rate (T3 25%) and (T1 30%) which depicts the less toxicity. The observed behavioral, biochemical, hematological and enzymological parameters were showed a significant increase in the treated BG dye. Extensive histopathological lesions in gill, liver and kidney tissues were observed in untreated BG dye compared to fishes grown in S. wightii-treated BG dye might be due to the stress caused by the toxic presence in the dye. The results concluded that S. wightii-treated BG dye does not have any inhibitory effect which reveals the nontoxic nature.


Assuntos
Carpas , Hematologia , Sargassum , Animais , Biodegradação Ambiental , Compostos de Amônio Quaternário
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