scholarly journals Effects of cigarette smoking on the growth of Streptococcus mutans biofilms: an in vitro study

Author(s):  
Ye Han

Abstract This study aimed to investigate the differences in growth and virulence (EPSs and acidogenicity) of Streptococcus mutans biofilms (S. mutans) according to the different times of cigarette smoking (CS) treatment. S. mutans biofilms (74-hour-old) were formed on saliva-coated hydroxyapatite disks. The biofilms were treated with CS at different times per day (one time, three times, and six times/day). The control group did not receive CS treatment. Acidogenicity, dry weight, colony-forming units, water-soluble/insoluble extracellular polysaccharides, and intracellular polysaccharides were analyzed and confocal laser scanning microscopy images were obtained of the 74-h-old biofilms. The 74-h-old biofilms on sHA discs in the 6 times/day CS treatment group showed the lowest biofilm accumulation and extracellular polysaccharide amount compared with the control group and other CS treatment groups. In the CLSM study, the biofilms in the six times/day CS treatment group also showed the lowest bacterial count (live and dead cells) and EPS biovolume. CS has an obvious inhibition on the growth of S. mutans biofilms, the degree of inhibition is proportional to the number of CS treatments.

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259895
Author(s):  
Ye Han

The increased incidence of dental caries by cigarette smoking (CS) has been widely reported in epidemiological studies, but the relationship between CS and cariogenic biofilm growth has been rarely studied. This study aims to investigate the effects of CS exposure on the growth and virulence of Streptococcus mutans biofilms (S. mutans). Briefly, S. mutans biofilms were formed on saliva-coated hydroxyapatite disks, which were exposed to CS 1, 3, and 6 times per day, respectively. In addition, S. mutans biofilms without CS exposure were considered as the control group. Acidogenicity, dry weight, colony-forming units (CFUs), water-soluble/insoluble extracellular polysaccharides (EPSs), and intracellular polysaccharides (IPSs) were analyzed and confocal laser scanning microscopy (CLSM) images of 74-h-old S. mutans biofilms were obtained. The lowest accumulation of biofilms and EPSs were detected in the 6 times/day CS exposure group compared with those of the control group and other CS exposure groups in 74-h-old S. mutans biofilms. CLSM also revealed the lowest bacterial count (live and dead cells) and EPSs biovolume in the six times/day CS exposure group in 74-h-old S. mutans biofilms. CS exposure inhibited the growth of S. mutans biofilm in vitro study, the anti-cariogenic biofilm formation was enhanced with a dose (frequency)-dependent at which frequency has more influence in the present findings.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Shaoe Zhang ◽  
Xiao Wang ◽  
Xiaotao Shi ◽  
Honglue Tan ◽  
Himanshu Garg

Background. External socking and washing with the Chinese herbal Sanhuang Jiedu decoction (SHJD) can effectively control local limb infections with bone and implant exposure. However, the antibiofilm activities of this decoction in vitro have not yet been investigated. Therefore, the aim of this study was to examine the effects and characteristics of SHJD on the mature biofilms of multidrug-resistant staphylococci on a titanium surface. Methods. Biofilm-forming methicillin-resistant Staphylococcus epidermidis ATCC 35984 and S. aureus ATCC 43330, and non-biofilm-forming S. epidermidis ATCC 12228 were selected as the experimental strains. The mature biofilms were prepared on titanium surfaces. The five experimental groups were based on dilution concentrations (DC) of SHJD: the control group (biofilm incubated with 0.85% NaCl solution), the SHJD (DC:1/8) group (initial SHJD solution was diluted 1/8), the SHJD (DC:1/4) group, the SHJD (DC:1/2) group, and the SHJD (DC:1/1) group (initial SHJD solution). The effects of SHJD on the mature biofilms were observed with the bacterial spread plate method, crystal violet (CV) staining, scanning electron microscopy, and confocal laser scanning microscopy. Results. After culture in tryptic soy broth for 72 h, ATCC 43300 and ATCC 35984 produced mature biofilms and ATCC 12228 did not. The optical density value of ATCC 12228 was 0.11 ± 0.02 , significantly lower than that of ATCC 35984 ( 0.42 ± 0.05 ) or ATCC 43300 ( 0.41 ± 0.03 ) ( P < 0.05 ). The mature biofilms of ATCC 43300 and ATCC 35984 clearly disintegrated when incubated for 12–24 h with SHJD (DC:1/1) or SHJD (DC:1/2), showing only scattered bacterial adhesion. In the SHJD (DC:1/4) group, although many residual bacterial colonies still clustered together, presenting a biofilm structure, it was very looser than that in the SHJD (DC:1/8) group in which the biofilm was similar to that in the control group. For ATCC 12228, only colony adhesion was observed, and the number of colonies decreased as the concentration of SHJD or the culture period increased. The quantitative results for the bacterial spread plate and CV staining showed significant differences between the SHJD groups ( P < 0.05 ). Conclusion. SHJD has antibiofilm activity against multidrug-resistant Staphylococcus strains. It weakens or disrupts already-formed mature biofilms on titanium surfaces in a concentration- and incubation time-dependent manner.


2009 ◽  
Vol 21 (1) ◽  
pp. 165
Author(s):  
M. A. Velazquez ◽  
H. Niemann

It has been hypothesized that high non-physiological IGF-1 levels are partially responsible for the recurrent pregnancy loss observed in women with the polycystic ovary syndrome (Eng GS et al. 2007 Diabetes 56, 2228–2234). The aim of this study was to determine the effect of supraphysiological concentrations of IGF-1 on blastocyst production and the occurrence of apoptosis in bovine embryos, which are a good model for human embryo development (Baumann CG et al. 2007 Mol. Reprod. Dev. 74, 1345–1353). COC obtained by slicing from abattoir ovaries were matured (TCM-199, Sigma) for 24 h and fertilized (Fert-TALP) for 18 h (Day 0) in vitro. Two different IGF-1 (Recombinant human IGF-1, R&D Systems GmbH, Wiesbaden, Germany) concentrations (supraphysiological = 1000 ng mL–1 and physiological = 100 ng mL–1) were added to the culture media (Synthetic oviduct fluid/BSA) and compared with a control group (no IGF-1 supplementation). On Day 8, blastocyst rates (22 replicates) were recorded and DNA degradation was detected in blastocyst nuclei using a cell death detection kit (Roche Diagnostics GmbH, Mannheim, Germany) based on the terminal deoxinucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) principle. Embryos (n = 27 [control], n = 29 [both IGF-1 groups]) from 4 replicates were examined by confocal laser scanning microscopy. Data were analyzed by ANOVA and the Fisher exact test using the SigmaStat 2.0 software package (Jandel Scientific, San Rafael, CA). Cleavage was numerically improved by both, 1000 (59.1 ± 1.8) and 100 (58.2 ± 2.8) ng IGF-1 over controls (53.5 ± 2.2), but the differences did not reach statistical significance (P = 0.22). The proportion of hatched blastocysts was enhanced by 100 (5.8 ± 1.0, P = 0.03) and 1000 (5.1 ± 0.7, P = 0.03) ng IGF-1 compared to controls (2.8 ± 0.6). Total blastocyst rate was increased by 100 ng IGF-1 (34.4 ± 1.9, P = 0.02) over controls (28.3 ± 1.7), but not by 1000 ng IGF-1 (29.1 ± 1.6 P = 0.75). The 100 ng IGF-1 group (38.5 ± 3.7) had fewer degenerated embryos (P = 0.01) compared to 1000 ng IGF-1 (49.7 ± 3.3). The proportion of embryos displaying at least one apoptotic cell was greater in the 1000 ng IGF-1 group over controls (96% v. 77% P = 0.04). The number of blastomeres with TUNEL-positive nuclei per embryo was higher in the supraphysiological group (5.5 ± 0.6, P < 0.001) compared with the control (2.3 ± 0.4) and the physiological group (2.5 ± 0.3). There were no significant differences between the control and the 100 ng IGF-1 group in this regard (P = 0.49). In conclusion, supraphysiological concentrations of IGF-1 do not increase blastocyst production but increase levels of apoptosis in bovine embryos produced in vitro. M. A. V. is in the PhD program of the University of Veterinary medicine, Hannover, Germany, and is supported by the German Academic Exchange Service (DAAD)


2020 ◽  
Vol 13 (06) ◽  
pp. 2050022
Author(s):  
Xiaoyue Liang ◽  
Zhaohui Zou ◽  
Zheng Zou ◽  
Changyi Li ◽  
Xiaoxi Dong ◽  
...  

The main objective of this study is to evaluate the antibacterial effect of antibacterial photodynamic therapy (aPDT) on Streptococcus mutans (S. mutans) biofilm model in vitro. The selection of photosensitizers is the key step for the efficacy of photodynamic therapy (PDT). However, no studies have been conducted in the oral field to compare the functional characteristics and application effects of PDT mediated by various photosensitizers. In this research, the antibacterial effect of Methylene blue (MB)/650[Formula: see text]nm laser and Hematoporphyrin monomethyl ether (HMME)/532[Formula: see text]nm laser on S. mutans biofilm was compared under different energy densities to provide experimental reference for the clinical application of the two PDT. The yield of lactic acid was analyzed by Colony forming unit (CFU) and spectrophotometry, and the complete biofilm activity was measured by Confocal Laser Scanning Microscopy (CLSM) to evaluate the bactericidal effect on each group. Based on the results of CFU, the bacterial colonies formed by 30.4[Formula: see text]J/cm2 532[Formula: see text]nm MB-aPDT group and 30.4[Formula: see text]J/cm2 532[Formula: see text]nm HMME-aPDT group were significantly less than those in other groups, and the bacterial colonies in HMME-aPDT group were less than those in HMME-aPDT group. Lactic acid production in all treatment groups except the photosensitizer group was statistically lower than that in the normal saline control group. The activity of bacterial plaque biofilm was significantly decreased in the two groups treated with 30.4[Formula: see text]J/cm2 aPDT. Therefore, aPDT suitable for energy measurement can kill S. mutans plaque biofilm, and MB-aPDT is better than HMME-aPDT.


2018 ◽  
Vol 27 (2) ◽  
Author(s):  
Tatit Nurseta ◽  
Yahya Irwanto ◽  
I W.A. Wiyasa ◽  
Rahajeng Rahajeng ◽  
Imelda Imelda ◽  
...  

Background: Several studies have reported that curcumin exerts chemopreventive effects in various type of cancers, through several mechanisms, however, the effect of curcumin on carcinogenesis in patients with hydatidiform mole has not yet been investigated. This study was conducted to evaluate the effect of curcumin on apoptosis, proliferation, and nuclear translocation of endothelial nitricoxide synthase in trophoblast cells induced by estradiol in complete hydatidiform mole (CHM).Methods: In this in vitro study, trophoblast cells were divided into six groups, the control group (trophoblast cells were exposed to 100 pg/mL of 17-β estradiol) and the treatment group (trophoblast cells were exposed to 100 pg/mL of 17-β estradiol in the presence of curcumin with doses: 50, 100, 200, 400, and 800 µM). At the end of study, the cell proliferation was analyzed using MTT assay and apoptosis with TUNEL test in each group thropoblast cell. eNOS translocation was assayed using confocal laser scanning microscopy at the various dose of curcumin.Results: Curcumin at the doses of 200, 400, and 800 µM significantly decreased the proliferation and increased the apoptotic index in curcumin-treated group compared to those in the control group (p<0.05). All doses of curcumin treatment significantly decreased the nuclear eNOS expression compared to that in the control group. The three highest doses of curcumin increased cytoplasmic eNOS expression compared to that in control group.Conclusion: Curcumin inhibits the proliferation and modulates the apoptosis of trophoblast cells induced by estradiol in CHM involvement.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Yalan Deng ◽  
Yingming Yang ◽  
Bin Zhang ◽  
Hong Chen ◽  
Yangyu Lu ◽  
...  

AbstractStreptococcus mutans (S. mutans) is generally regarded as a major contributor to dental caries because of its ability to synthesize extracellular polysaccharides (EPS) that aid in the formation of plaque biofilm. The VicRKX system of S. mutans plays an important role in biofilm formation. The aim of this study was to investigate the effects of vicK gene on specific characteristics of EPS in S. mutans biofilm. We constructed single-species biofilms formed by different mutants of vicK gene. Production and distribution of EPS were detected through atomic force microscopy, scanning electron microscopy and confocal laser scanning microscopy. Microcosmic structures of EPS were analyzed by gel permeation chromatography and gas chromatography-mass spectrometry. Cariogenicity of the vicK mutant was assessed in a specific pathogen-free rat model. Transcriptional levels of cariogenicity-associated genes were confirmed by quantitative real-time polymerase chain reaction. The results showed that deletion of vicK gene suppressed biofilm formation as well as EPS production, and EPS were synthesized mostly around the cells. Molecular weight and monosaccharide components underwent evident alterations. Biofilms formed in vivo were sparse and contributed a decreased degree of caries. Moreover, expressional levels of genes related to EPS synthesis were down-regulated, except for gtfB. Our report demonstrates that vicK gene enhances biofilm formation and subsequent caries development. And this may due to its regulations on EPS metabolism, like synthesis or microcosmic features of EPS. This study suggests that vicK gene and EPS can be considered as promising targets to modulate dental caries.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1809
Author(s):  
Jifen Zhang ◽  
Yanhua Wang ◽  
Jirui Wang ◽  
Tao Yi

A drug nanocrystals self-stabilized Pickering emulsion (NSSPE) with a unique composition and microstructure has been proven to significantly increase the bioavailability of poorly soluble drugs. This study aimed to develop a new solid NSSPE of puerarin preserving the original microstructure of NSSPE by spray-drying. A series of water-soluble solid carriers were compared and then Box-Behnken design was used to optimize the parameters of spray-drying. The drug release and stability of the optimized solid NSSPE in vitro were also investigated. The results showed that hydroxypropyl-β-cyclodextrin (HP-β-CD), rather than solid carriers commonly used in solidification of traditional Pickering emulsions, was suitable for the solid NSSPE to retain the original appearance and size of emulsion droplets after reconstitution. The amount of HP-β-CD had more influences on the solid NSSPE than the feed rate and the inlet air temperature. Fluorescence microscopy, confocal laser scanning microscopy and scanning electron microscopy showed that the reconstituted emulsion of the solid NSSPE prepared with HP-β-CD had the same core-shell structure with a core of oil and a shell of puerarin nanocrystals as the liquid NSSPE. The particle size of puerarin nanocrystal sand interfacial adsorption rate also did not change significantly. The cumulative amount of released puerarin from the solid NSSPE had no significant difference compared with the liquid NSSPE, which were both significantly higher than that of puerarin crude material. The solid NSSPE was stable for 3 months under the accelerated condition of 75% relative humidity and 40 °C. Thus, it is possible todevelop the solid NSSPE preserving the unique microstructure and the superior properties in vitro of the liquid NSSPE for poorly soluble drugs.


2018 ◽  
Vol 53 (3) ◽  
pp. 322-331 ◽  
Author(s):  
Aline A. Sampaio ◽  
Samilly E. Souza ◽  
Antônio P. Ricomini-Filho ◽  
Altair A. Del Bel Cury ◽  
Yuri W. Cavalcanti ◽  
...  

Streptococcus mutans are considered the most cariogenic bacteria, but it has been suggested that Candida albicans could increase their cariogenicity. However, the effect of this dual-species microorganisms’ combination on dentine caries has not been experimentally evaluated. Biofilms of C. albicans, S. mutans and C. albicans + S. mutans (n = 12/biofilm) were grown in ultra-filtered tryptone yeast extract broth culture medium for 96 h on root dentine slabs of known surface hardness and exposed 8 times per day for 3 min to 10% sucrose. The medium was changed 2 times per day (after the 8 cariogenic challenges and after the overnight period of famine), and aliquots were analyzed to determinate the pH (indicator of biofilm acidogenicity). After 96 h, the biofilms were collected to determine the wet weight, colony-forming units, and the amounts of extracellular polysaccharides (soluble and insoluble). Dentine demineralization was assessed by surface hardness loss (% SHL). The architecture of the biofilms was analyzed by confocal laser scanning microscopy (CLSM) and transmission electron microscopy (TEM). Data were analyzed by ANOVA followed by Tukey’s test (α = 0.05). The dual-species C. albicans + S. mutans biofilm provoked higher % SHL on dentine (p < 0.05) than the S. mutans and C. albicans biofilm. This was supported by the results of biofilm acidogenicity and the amounts of soluble (6.4 ± 2.14 vs. 4.0 ± 0.94 and 1.9 ± 0.97, respectively) and insoluble extracellular polysaccharides (24.9 ± 9.22 vs. 18.9 ± 5.92 and 0.7 ± 0.48, respectively) (p < 0.05). The C. albicans biofilm alone presented low cariogenicity. The images by CLSM and TEM, respectively, suggest that the C. albicans + S. mutans biofilm is more voluminous than the S. mutans biofilm, and S. mutans cells interact with C. albicans throughout polysaccharides from the biofilm matrix. These findings show that C. albicans enhances the cariogenic potential of the S. mutans biofilm, increasing dentine demineralization.


Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3517
Author(s):  
Mariia Chernykh ◽  
Dmytro Zavalny ◽  
Viktoriya Sokolova ◽  
Stanislav Ponomarenko ◽  
Svitlana Prylutska ◽  
...  

A new water-soluble thermosensitive star-like copolymer, dextran-graft-poly-N-iso-propilacrylamide (D-g-PNIPAM), was created and characterized by various techniques (size-exclusion chromatography, differential scanning calorimetry, Fourier-transform infrared (FTIR) spectroscopy, and dynamic light scattering (DLS) spectroscopy). The viability of cancer cell lines (human transformed cervix epithelial cells, HeLa) as a model for cancer cells was studied using MTT and Live/Dead assays after incubation with a D-g-PNIPAM copolymer as a carrier for the drug doxorubicin (Dox) as well as a D-g-PNIPAM + Dox mixture as a function of the concentration. FTIR spectroscopy clearly indicated the complex formation of Dox with the D-g-PNIPAM copolymer. The size distribution of particles in Hank’s solution was determined by the DLS technique at different temperatures. The in vitro uptake of the studied D-g-PNIPAM + Dox nanoparticles into cancer cells was demonstrated by confocal laser scanning microscopy. It was found that D-g-PNIPAM + Dox nanoparticles in contrast to Dox alone showed higher toxicity toward cancer cells. All of the aforementioned facts indicate a possibility of further preclinical studies of the water-soluble D-g-PNIPAM particles’ behavior in animal tumor models in vivo as promising carriers of anticancer agents.


2010 ◽  
Vol 55 (2) ◽  
pp. 860-866 ◽  
Author(s):  
Zhao-Xiang Peng ◽  
Bing Tu ◽  
Yang Shen ◽  
Lin Du ◽  
Ling Wang ◽  
...  

ABSTRACTOur previous study (Z. X. Peng et al., Carbohydr. Polym.81:275-283, 2010) demonstrated that water-soluble quaternary ammonium salts, which are produced by the reaction of chitosan with glycidyl trimethylammonium chloride, provide chitosan derivatives with enhanced antibacterial ability. Because biofilm formation is believed to comprise the key step in the development of orthopedic implant-related infections, we further evaluated the efficacy of hydroxypropyltrimethyl ammonium chloride chitosan (HACC) with different degrees of substitution (DS; referred to as HACC 6%, 18%, and 44%) in preventing biofilm formation on a titanium surface. We used a tissue culture plate method to quantify the biomass ofStaphylococcus epidermidisandStaphylococcus aureusbiofilms and found that HACC, especially HACC 18% and 44%, significantly inhibited biofilm formation compared to the untreated control, even at concentrations far below their MICs (P< 0.05). Scanning electron microscopy showed that inhibition of biofilm formation on titanium increased dramatically with increased DS and HACC concentrations. Confocal laser scanning microscopy indicated that growth of a preexisting biofilm on titanium was inhibited by concentrations of HACC 18% and 44% below their minimum biofilm eradication concentrations. We also demonstrated that HACC inhibited the expression oficaA, which mediates the production of extracellular polysaccharides, both in new biofilms and in preexisting biofilms on titanium. Our results indicate that HACC may serve as a new antibacterial agent to inhibit biofilm formation and prevent orthopedic implant-related infections.


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