Combination effect of diurnal exposure to sucrose and nocturnal exposure to lactose on enamel demineralization

2021 ◽  
Author(s):  
Juliana Campos Vieira ◽  
Jaime Aparecido Cury ◽  
Antonio Pedro Ricomini Filho
Keyword(s):  
Culture Medium ◽  
Sucrose Solution ◽  
Surface Hardness ◽  
Extracellular Polysaccharides ◽  
Medium Ph ◽  
Lactose Fermentation ◽  
The Media ◽  
Bovine Enamel ◽  
One Way Anova ◽  
Chemical Indicator

We have hypothesized that the association between human milk and caries in breastfeeding children could be explained by the combination of a diurnal cariogenic diet with the nocturnal lactose fermentation, conditions simulated in this experimental study. Cariogenic biofilm was formed on bovine enamel slabs, which were exposed 8x/day for 3 min to a 10% sucrose solution, simulating a highly cariogenic diurnal diet, or 50 mM NaCl solution (control). Simulating the nocturnal retention of milk in mouth, biofilms were transferred to culture medium containing 0.7% lactose for 2 h, or only to culture medium (control). Four groups were designed (n=12): Ctrl, no exposure to diurnal sucrose or nocturnal lactose; Lac, only nocturnal exposure to lactose (2 h); Suc, only diurnal exposure to sucrose (8x/day); and Suc→Lac, diurnal exposure to sucrose (8x/day) followed by nocturnal exposure to lactose (2 h). The medium was changed 3x/day, at the beginning of the day, and after diurnal and nocturnal exposures. Calcium in the medium was determined as chemical indicator of partial demineralizations occurred during the diurnal and the nocturnal treatments; the medium pH was also determined. After 96 h of growth, biofilms were harvested to evaluate CFU, biomass, and extracellular polysaccharides, soluble and insoluble. The percentage of enamel surface hardness loss (%SHL) was evaluated as cumulative demineralization. Data were analyzed by one-way ANOVA, Tukey’s test (α=5%). Highest %SHL (p<0.05) was found for Suc→Lac (40.6%) group when compared to Suc (32.1%), Lac (7.7%), and Ctrl (3.8%). Calcium released during the diurnal and nocturnal treatments were respectively: Suc→Lac=Suc>Lac=Ctrl and Suc→Lac=Lac>Suc=Ctrl (p<0.05). Regarding Ctr group, calcium released from nocturnal lactose fermentation by Suc→Lac group was 4-fold greater than that provoked by Lac group. The findings were supported by the pH of the media. The data suggest that the biofilm formed under diurnal exposure to sucrose enhances the cariogenicity of nocturnal exposure to lactose.

Cariogenic Potential of Human and Bovine Milk on Enamel Demineralization

2021 ◽  
pp. 1-8
Author(s):  
Antonio P. Ricomini Filho ◽  
Ana Camila M. de Assis ◽  
Bárbara E. Costa Oliveira ◽  
Jaime A. Cury
Keyword(s):  
Human Milk ◽  
Bovine Milk ◽  
Surface Hardness ◽  
Human Saliva ◽  
Positive Control ◽  
Negative Control ◽  
Extracellular Polysaccharides ◽  
Enamel Demineralization ◽  
Biofilm Model ◽  
Bovine Enamel

The higher cariogenicity of human milk when compared with bovine milk is still a debatable subject. Therefore, we evaluated the effect of human or bovine milk exposure on biofilm composition and enamel demineralization using a validated cariogenic biofilm model. <i>Streptococcus mutans</i> UA159 biofilms (<i>n</i> = 8) were grown on human saliva-coated bovine enamel slabs of known surface hardness. The biofilms were exposed 8×/day to 0.9% NaCl (negative control), human milk, bovine milk, 7.0% lactose (active human milk control), 4.5% lactose (active bovine milk control), or 10% sucrose (positive control). The culture medium was changed twice daily, and the pH was analyzed as an indicator of biofilm acidogenicity. After 120 h of growth, biofilms were harvested to evaluate viable cells, and soluble and insoluble extracellular polysaccharides (EPS). Enamel demineralization was assessed by the percentage of surface hardness loss (%SHL). Data were analyzed by one-way ANOVA/Tukey’s test (α = 5%). In terms of %SHL, negative control (7.7 ± 3.1), human milk control (13.3 ± 7.5), bovine milk control (15.3 ± 8.2), human milk (7.5 ± 5.0), and bovine milk (8.7 ± 6.3) did not differ among them (<i>p</i> &#x3e; 0.05) but differed (<i>p</i> &#x3c; 0.05) from sucrose (55.1 ± 5.4). The findings of enamel demineralization (%SHL) were statistically supported by the data of biofilm acidogenicity, bacterial counts and EPS biofilm composition. This experimental study suggests that human and bovine milk have low cariogenic potential to provoke caries lesions in enamel.

In situ Effect of Arginine-Containing Dentifrice on Plaque Composition and on Enamel Demineralization under Distinct Cariogenic Conditions

2018 ◽  
Vol 52 (6) ◽  
pp. 588-597 ◽  
Author(s):  
Angel Y. Sanchez ◽  
Caroline L. de Oliveira ◽  
Thais C. Negrini ◽  
Lina N. Hashizume ◽  
Anderson T. Hara ◽  
...  
Keyword(s):  
Sucrose Solution ◽  
Surface Hardness ◽  
Extracellular Polysaccharide ◽  
Experimental Phase ◽  
Enamel Demineralization ◽  
Bovine Enamel ◽  
Adult Volunteers ◽  
Mineral Loss ◽  
In Situ Split

There is limited evidence that arginine-containing fluoridated dentifrices (AFD) have a better anticaries effect than regular fluoridated dentifrices (FD), especially in subjects at a higher risk for caries development. This study aimed to assess the effect of AFD on enamel demineralization and on the microbial and biochemical compositions of biofilm formed under different frequencies of sucrose exposure. It consisted of an in situ split-mouth design, where 12 adult volunteers who used FD for at least 2 months prior to the beginning of this study wore acrylic palatal appliances containing 4 bovine enamel specimens (1 pair at each side of the appliance) during 2 phases of 14 days each. FD slurry (3×/day) and 20% sucrose solution (4× and 8×/day) were dripped on the specimens during the first experimental phase. The same volunteers then used AFD during a 2-month washout period, followed by a second experimental phase where the AFD slurry and sucrose solution were applied onto a new subset of specimens. The percentage of enamel surface hardness loss (%SHL), the lesion depth (LD), the integrated mineral loss (IML), microbial counts on biofilms, the biomass, and inorganic and insoluble extracellular polysaccharide (IEPS) biofilm concentrations were determined. Higher %SHL, biomass, and IEPS and lower fluoride values were found at sucrose 8×/day exposure. Lower IEPS were found in the presence of AFD compared to FD. Similar %SHL, LD, and IML values were found between FD and AFD, irrespectively of the cariogenic challenge. The results suggest that AFD have an anticaries effect similar to that of regular FD.

scholarly journals Viability of ‘Candidatus Liberibacter asiaticus’ Prolonged by Addition of Citrus Juice to Culture Medium

2014 ◽  
Vol 104 (1) ◽  
pp. 15-26 ◽  
Author(s):  
Jennifer K. Parker ◽  
Sarah R. Wisotsky ◽  
Evan G. Johnson ◽  
Faraj M. Hijaz ◽  
Nabil Killiny ◽  
...  
Keyword(s):  
Grapefruit Juice ◽  
Culture Medium ◽  
Quantitative Polymerase Chain Reaction ◽  
Chemical Characterization ◽  
Candidatus Liberibacter Asiaticus ◽  
Citrus Greening Disease ◽  
Candidatus Liberibacter ◽  
The Media ◽  
Liberibacter Asiaticus

Huanglongbing, or citrus greening disease, is associated with infection by the phloem-limited bacterium ‘Candidatus Liberibacter asiaticus’. Infection with ‘Ca. L. asiaticus’ is incurable; therefore, knowledge regarding ‘Ca. L. asiaticus’ biology and pathogenesis is essential to develop a treatment. However, ‘Ca. L. asiaticus’ cannot currently be successfully cultured, limiting its study. To gain insight into the conditions conducive for growth of ‘Ca. L. asiaticus’ in vitro, ‘Ca. L. asiaticus’ inoculum obtained from seed of fruit from infected pomelo trees (Citrus maxima ‘Mato Buntan’) was added to different media, and cell viability was monitored for up to 2 months using quantitative polymerase chain reaction in conjunction with ethidium monoazide. Media tested included one-third King's B (K), K with 50% juice from the infected fruit, K with 50% commercially available grapefruit juice, and 100% commercially available grapefruit juice. Results show that juice-containing media dramatically prolong viability compared with K in experiments reproduced during 2 years using different juice sources. Furthermore, biofilm formed at the air–liquid interface of juice cultures contained ‘Ca. L. asiaticus’ cells, though next-generation sequencing indicated that other bacterial genera were predominant. Chemical characterization of the media was conducted to discuss possible factors sustaining ‘Ca. L. asiaticus’ viability in vitro, which will contribute to future development of a culture medium for ‘Ca. L. asiaticus’.

Biochemical markers for pregnancy in the spent culture medium of in vitro produced bovine embryos

2021 ◽  
Author(s):  
Gabriela de Oliveira Fernandes ◽  
Marcella Pecora Milazzotto ◽  
Andrei Antonioni Guedes Fidelis ◽  
Taynan Stonoga Kawamoto ◽  
Ligiane de Oliveira Leme ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Biochemical Markers ◽  
Culture Medium ◽  
Culture Media ◽  
Ionization Mass ◽  
Metabolic Profiles ◽  
Bovine Embryos ◽  
The Media

Abstract The present study aimed to identify biomarkers to assess the quality of in vitro produced (IVP) bovine embryos in the culture media. IVP embryos on Day (D) 5 of development were transferred to individual drops, where they were maintained for the last 48 h of culture. Thereafter, the medium was collected and the embryos were transferred to the recipients. After pregnancy diagnosis, the media were grouped into the pregnant and nonpregnant groups. The metabolic profiles of the media were analyzed via electrospray ionization mass spectrometry, and the concentrations of pyruvate, lactate, and glutamate were assessed using fluorimetry. The spectrometric profile revealed that the media from embryos from the pregnant group presented a higher signal intensity compared to that of the nonpregnant group; the ions 156.13 Da [M + H]+, 444.33 Da [M + H]+, and 305.97 Da [M + H]+ were identified as biomarkers. Spent culture medium from expanded blastocysts (Bx) that established pregnancy had a greater concentration of pyruvate (p = 0.0174) and lesser concentration of lactate (p = 0.042) than spent culture medium from Bx that did not establish pregnancy. Moreover, pyruvate in the culture media of Bx can predict pregnancy with 90.9% sensitivity and 75% specificity. In conclusion, we identified markers in the culture media that helped in assessing the most viable IVP embryos with a greater potential to establish pregnancy.

scholarly journals Effect of medium pH and cultivation period on mycelial biomass, polysaccharide, and ligninolytic enzyme production by Ganoderma lucidum from Montenegro

2006 ◽  
Vol 58 (3) ◽  
pp. 179-182 ◽  
Author(s):  
Jelena Vukojevic ◽  
Mirjana Stajic ◽  
Sonja Duletic-Lausevic ◽  
Jasmina Simonic
Keyword(s):  
Ganoderma Lucidum ◽  
Enzyme Production ◽  
Ligninolytic Enzymes ◽  
Extracellular Polysaccharide ◽  
Ligninolytic Enzyme ◽  
Extracellular Polysaccharides ◽  
Medium Ph ◽  
Polysaccharide Production ◽  
Intracellular Polysaccharide ◽  
Maximal Production

The effect of initial medium pH on biomass, extracellular and intracellular polysaccharide, and ligninolytic enzyme production by Ganoderma lucidum was investigated at different pH values after 7 and 14 days of cultivation. Maximal production of biomass was recorded at pH 4.5 and 5.0; maximal production of extracellular polysaccharides at pH 7.0 and 3.0; and maximal production of intracellular polysaccharides at pH 7.0 and 5.5. Ligninolytic enzymes were not produced at any pH of the medium. Maximal biomass production was obtained on the 11th day of cultivation; maximal extracellular polysaccharide production on the 7th day; and maximal intracellular polysaccharide production on the 6th and 10th day of cultivation. .

scholarly journals The effect of low initial medium pH on in vitro white poplar growth

2013 ◽  
pp. 67-80
Author(s):  
Branislav Kovacevic ◽  
Dragana Miladinovic ◽  
Marina Katanic ◽  
Zoran Tomovic ◽  
Sasa Pekec
Keyword(s):  
Biomass Accumulation ◽  
Dry Mass ◽  
White Poplar ◽  
Medium Ph ◽  
Shoot Height ◽  
Initial Ph ◽  
The Media ◽  
Initial Medium ◽  
Shoot Mass

The effect of low initial medium pH on shoot and root development of five white poplar (Populus alba L.) genotypes was tested. The shoot height, fresh mass of shoots per jar, dry mass of shoots per jar, number of roots, as well as the length of the longest root were measured and final pH of the media determined, after 35 days of culture in vitro. Three initial pH values of the medium were tested: 3.0, 4.0 and 5.5 as control. Agar solidification at pH 3.0 was not achieved after sterilization in autoclave, but it was successful after sterilizing in a microwave oven. The obtained results indicate that the tested genotypes are able to significantly influence the changes of media pH during culture. The effect of differences among the examined media was significant for biomass accumulation and final media pH. Generally, significantly higher values of fresh and dry shoot mass, shoot height and the longest root length were recorded on a medium with initial pH 3.0 then on a standard medium with pH 5.5.The implications of the obtained results for the improvement of in vitro propagation of white poplars are discussed.

scholarly journals Glycoprotein metabolism in normal and β-mannosidase-deficient cultured goat skin fibroblasts

1986 ◽  
Vol 234 (1) ◽  
pp. 175-183 ◽  
Author(s):  
L W Hancock ◽  
M Z Jones ◽  
G Dawson
Keyword(s):  
Culture Medium ◽  
Human Fibroblasts ◽  
Skin Fibroblasts ◽  
Medium Ph ◽  
Cytosolic Ph ◽  
Catabolic Pathways ◽  
No Conversion ◽  
Lysosomal Ph ◽  
Cultured Skin ◽  
Oligosaccharide Structures

Cultured skin fibroblasts established from goats affected with beta-mannosidosis, an inherited neurovisceral storage disorder, showed an absence of lysosomal beta-mannosidase activity and the corresponding accumulation of a trisaccharide (TS) with the structure Man beta (1→4)GlcNAc beta (1→4)GlcNAc (0.4 mumol/g) and lesser amounts (0.15 mumol/g) of a Man beta (1→4)GlcNAc disaccharide (DS). By using purified storage TS isolated from fibroblasts metabolically labelled with [3H]GlcN, no conversion of TS into DS could be demonstrated in homogenates of affected cells at either lysosomal pH (4.4) or cytosolic pH (6.1), or in the culture medium (pH 7.0) of affected cells. Both TS and DS were secreted into the culture medium by affected fibroblasts. When affected fibroblasts were treated with tunicamycin before labelling with [3H]GlcN, the accumulation of both labelled TS and DS was completely inhibited. Treatment of both affected and normal goat fibroblasts with swainsonine resulted in the inhibition of lysosomal alpha-mannosidase activity and in the accumulation of the same labelled oligosaccharides in both. The major storage pentasaccharide from both normal and affected swainsonine-treated fibroblasts was sensitive to digestion with alpha-mannosidase and endo-beta-N-acetylhexosaminidase D, suggesting a branched mannose structure and a chitobiose core. In the absence of evidence for the existence of unusual N-linked glycoprotein-associated chitotriose oligosaccharide structures in affected goat fibroblasts, it must be concluded that degradative pathways for N-linked oligosaccharides are similar in both normal and affected goat fibroblasts, and that these pathways differ from catabolic pathways in human fibroblasts.

Effect of Fluoride Toothpaste Containing Nano-Sized Sodium Hexametaphosphate on Enamel Remineralization: An in situ Study

2018 ◽  
Vol 53 (3) ◽  
pp. 260-267 ◽  
Author(s):  
Marcelle Danelon ◽  
Luhana G. Garcia ◽  
Juliano P. Pessan ◽  
Amanda Passarinho ◽  
Emerson R. Camargo ◽  
...  
Keyword(s):  
Surface Hardness ◽  
Sodium Hexametaphosphate ◽  
Treatment Groups ◽  
Fluoride Toothpaste ◽  
Integrated Recovery ◽  
Phase Surface ◽  
Double Blinded ◽  
Bovine Enamel ◽  
Caries Lesions

Objective: To evaluate the remineralizing potential of a conventional toothpaste (1,100 ppm F) supplemented with nano-sized sodium hexametaphosphate (HMPnano) in artificial caries lesions in situ. Design: This double-blinded crossed study was performed in 4 phases of 3 days each. Twelve subjects used palatal appliances containing 4 bovine enamel blocks with artificial caries lesions. Volunteers were randomly assigned into the following treatment groups: no F/HMP/HMPnano (Placebo); 1,100 ppm F (1100F); 1100F plus 0.5% micrometric HMP (1100F/HMP) and 1100F plus 0.5% nano-sized HMP (1100F/HMPnano). Volunteers were instructed to brush their natural teeth with the palatal appliances in the mouth for 1 min (3 times/day), so that blocks were treated with natural slurries of toothpastes. After each phase, surface hardness post-remineralization (SH2), integrated recovery of subsurface hardness (ΔIHR), integrated mineral recovery (ΔIMR) and enamel F concentration were determined. Data were submitted to analysis of variance and Student-Newman-Keuls’ test (p < 0.001). Results: Enamel surface became 42% harder when treated with 1100F/HMPnano in comparison with 1100F (p < 0.001). Treatment with 1100F/HMP and 1100F/HMPnano promoted an increase of ∼23 and ∼87%, respectively, in ΔIHR when compared to 1100F (p < 0.001). In addition, ΔIMR for the 1100F/HMPnano was ∼75 and ∼33% higher when compared to 1100F and 1100F/HMP respectively (p < 0.001). Enamel F uptake was similar among all groups except for the placebo (p < 0.001). Conclusion: The addition of 0.5% HMPnano to a conventional fluoride toothpaste was able to promote an additional remineralizing effect of artificial caries lesions.

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