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Medicina (Kaunas, Lithuania) Oct 2021: species are part of the normal flora of humans and rarely cause disease. It is an uncommon cause of disease in humans. The clinical features of actinomycosis have...
: species are part of the normal flora of humans and rarely cause disease. It is an uncommon cause of disease in humans. The clinical features of actinomycosis have been described, and various anatomical sites (such as face, bones and joints, respiratory tract, genitourinary tract, digestive tract, central nervous system, skin, and soft tissue structures) can be affected. It is not easy to identify actinomycosis because it sometimes mimics cancer due to under-recognition. As new diagnostic methods have been applied, can now more easily be identified at the species level. Recent studies have also highlighted differences among species. We report a case of bacteremia with cutaneous actinomycosis. : A 66 years old male developed fever for a day with progressive right lower-leg erythematous swelling. Blood culture isolates yielded species, which was identified as by sequencing of the 16S rRNA gene. In addition, we searched for the term or actinomycosis cross-referenced with bacteremia or "blood culture" or "blood stream" from January 2010 to July 2020. The infectious diseases caused by species of from January 1977 to July 2020 were also reviewed. : The patient recovered well after intravenous ampicillin treatment. Poor oral hygiene was confirmed by dental examination. There were no disease relapses during the following period. Most cases of actinomycosis can be treated with penicillin. However, clinical alertness, risk factor evaluation, and identification of species can prevent inappropriate antibiotic or intervention. We also compiled a total of 18 cases of bacteremia after conducting an online database search. : In summary, we describe a case of fever and progressive cellulitis. species was isolated from blood culture, which was further identified as by 16S rRNA sequencing. The cellulitis improved after pathogen-directed antibiotics. Evaluation of risk factors in patients with bacteremia and further identification of the species are recommended for successful treatment.
Topics: Actinomyces; Actinomyces viscosus; Actinomycosis; Aged; Bacteremia; Humans; Male; RNA, Ribosomal, 16S
PubMed: 34684101
DOI: 10.3390/medicina57101064 -
Frontiers in Bioengineering and... 2022Peri-implantitis is the leading cause of dental implant failure, initially raised by biofilm accumulation on the implant surface. During the development of biofilm, ()...
Peri-implantitis is the leading cause of dental implant failure, initially raised by biofilm accumulation on the implant surface. During the development of biofilm, () plays a pivotal role in initial attachment as well as the bacterial coaggregation of multispecies pathogens. Hence, eliminating the -associated biofilm is fundamental for the regeneration of the lost bone around implants. Whereas clinical evidence indicated that antimicrobials and debridement did not show significant effects on the decontamination of biofilm on the implant surface. In this study, alpha-amylase was investigated for its effects on disassembling biofilm. Then, in order to substantially disperse biofilm under biosafety concentration, D-arginine was employed to appraise its enhancing effects on alpha-amylase. In addition, molecular dynamics simulations and molecular docking were conducted to elucidate the mechanism of D-arginine enhancing alpha-amylase. 0.1-0.5% alpha-amylase showed significant effects on disassembling biofilm, with definite cytotoxicity toward MC3T3-E1 cells meanwhile. Intriguingly, 8 mM D-arginine drastically enhanced the eradication of biofilm biomass by 0.01% alpha-amylase with biosafety in 30 min. The exopolysaccharides of biofilm were also thoroughly hydrolyzed by 0.01% alpha-amylase with 8 mM D-arginine. The biofilm thickness and integrity were disrupted, and the exopolysaccharides among the extracellular matrix were elusive. Molecular dynamics simulations showed that with the hydrogen bonding of D-arginine to the catalytic triad and calcium-binding regions of alpha-amylase, the atom fluctuation of the structure was attenuated. The distances between catalytic triad were shortened, and the calcium-binding regions became more stable. Molecular docking scores revealed that D-arginine facilitated the maltotetraose binding process of alpha-amylase. In conclusion, these results demonstrate that D-arginine enhances the disassembly effects of alpha-amylase on biofilm through potentiating the catalytic triad and stabilizing the calcium-binding regions, thus providing a novel strategy for the decontamination of biofilm contaminated implant surface.
PubMed: 35309977
DOI: 10.3389/fbioe.2022.864012 -
Annals of Medicine and Surgery (2012) Sep 2022The present study aims to study antibacterial effects and cellular mechanisms of iron oxide magnetic nanoparticles loaded with piroctone olamine (Fe3O4@PO NPs) against...
BACKGROUND
The present study aims to study antibacterial effects and cellular mechanisms of iron oxide magnetic nanoparticles loaded with piroctone olamine (Fe3O4@PO NPs) against some cariogenic bacteria ( and
METHODS
Nanoparticles was synthesized by the coprecipitation method. Antibacterial effects of Fe3O4@PO NPs were performed by calculating the minimum inhibitory concentration (MIC). We also evaluated the level of reactive oxygen species (ROS) and protein leakage to assess whether antibacterial effects may be dependent on these mechanisms.
RESULTS
The results demonstrated that PO showed the lowest antibacterial effect compared to other drugs tested with MICs values of 53.33 and 64 μg/ml for and , respectively. In contrast, the highest antibacterial effect was related to Fe3O4@PONPs with MICs values of 2.66 and 3.33 μg/ml for and , respectively. Fe3O4@PONPs, Fe3O4MNP, and PO markedly increased (p < 0.001) ROS production and protein leakage of tested bacteria at ≥¼ MIC, ≥1/3 MIC, and ½ MIC, respectively.
CONCLUSION
The findings of the present survey revealed the promising antibacterial effects of Fe3O4@PONP against some cariogenic bacteria; whereas it triggered the ROS production and protein leakage as the possible antibacterial mode of action of anti-infective agents. However, additional surveys are necessary to elucidate the accurate mechanisms of these nanoparticles.
PubMed: 36147164
DOI: 10.1016/j.amsu.2022.104291 -
Frontiers in Microbiology 2022To investigate the degradation effect of bovine trypsin on multispecies biofilm of periodontitis-related bacteria and to provide an experimental reference for exploring...
To investigate the degradation effect of bovine trypsin on multispecies biofilm of periodontitis-related bacteria and to provide an experimental reference for exploring new methods for controlling biofilms of periodontitis-related microorganisms, the multispecies biofilm of periodontitis-related microorganisms was established. Standard strains of subsp. , , and were co-cultured to form the biofilm. The experimental groups were treated with bovine trypsin, distilled water was applied as the blank control group, and phosphate saline buffer (pH = 7.4) as the negative control group. Morphological observation and quantitative analysis of extracellular polymeric substances (EPS), live bacteria, and dead bacteria were conducted using a laser confocal microscope. The morphological changes of EPS and bacteria were also observed using a scanning electron microscope. The results of morphological observations of modeling were as follows. EPS aggregated as agglomerates, and bacteria flora were wrapped by them, showing a three-dimensional network structure, and channel-like structures were inside the biofilm. Live bacteria were distributed on the surface of the EPS or embedded in them, dead bacteria aggregated between live flora and the bottom layer of biofilms. After being treated with bovine trypsin, the three-dimensional network structure and the channel-like structure disappeared, and the EPS and live and dead bacteria decreased. Quantitative analysis results are as follows. When biofilm was treated for 30 s, 1 min, and 3 min, the minimum effective concentrations of bovine trypsin to reduce EPS were 2 mg/ml ( < 0.05), 0.5 mg/ml ( < 0.05), and 0.25 mg/ml ( < 0.05), respectively. The minimum effective concentrations of bovine trypsin to reduce the live or dead bacteria were 2 mg/ml ( < 0.05), 0.5 mg/ml ( < 0.05), and 0.5 mg/ml ( < 0.05), respectively. There was no significant difference in the ratio of live/dead bacteria after the biofilm was treated for 30 s with bovine trypsin at the concentration of 0.25, 0.5, 1, and 2 mg/ml ( > 0.05), and the minimum effective concentration to reduce the ratio of live bacteria/dead bacteria was 0.25 mg/ml ( < 0.05) after treatment for 1 min and 3 min. Therefore, bovine trypsin can destroy biofilm structure, disperse biofilm and bacteria flora, and reduce the EPS and bacterial biomass, which are positively correlated with the application time and concentration.
PubMed: 35992661
DOI: 10.3389/fmicb.2022.951291 -
Journal of Advanced Pharmaceutical... 2021This study is aimed to test the efficacy of C-10 Massoia lactone in oral polymicrobial degradation. Polymicrobial of , , , and were studied. C-10 Massoia lactone...
This study is aimed to test the efficacy of C-10 Massoia lactone in oral polymicrobial degradation. Polymicrobial of , , , and were studied. C-10 Massoia lactone against biofilm degradation was investigated using modified crystal violet for biofilm staining. The effectiveness of C-10 Massoia lactone against biofilms was calculated by the minimum biofilm inhibitory concentration (MBIC) and the minimum value of biofilm eradication concentration (MBEC). Scanning electron microscope was used to study biofilm cell viability and morphological changes. The results showed a degradation effect of C-10 Massoia lactone against mature oral polymicrobial at 0.25% v/v. C-10 Massoia lactone can degrade polymicrobial biofilms of , , and . This compound can destroy the extracellular polymeric substances (EPS) of polymicrobial biofilms. The potential application of C-10 Massoia lactone for anti-polymicrobial medication should be applied in such a way that any negative effects are minimized. Further research is needed to confirm the findings of this study.
PubMed: 33532362
DOI: 10.4103/japtr.JAPTR_105_20 -
Frontiers in Microbiology 2023Actinomycetes can colonize surfaces of tools and equipment and can be transferred to meat and meat products during manufacture, processing, handling, and storage....
Screening, molecular identification, population diversity, and antibiotic susceptibility pattern of Actinomycetes species isolated from meat and meat products of slaughterhouses, restaurants, and meat stores of a developing country, Iran.
INTRODUCTION
Actinomycetes can colonize surfaces of tools and equipment and can be transferred to meat and meat products during manufacture, processing, handling, and storage. Moreover, washing the meat does not eliminate the microorganisms; it only spreads them. As a result, these opportunistic pathogens can enter the human body and cause various infections. Therefore, the aim of the current study was to screen, identify, and determine the antibiotic susceptibility of Actinomycetes species from meat and meat products in the Markazi province of Iran.
METHODS
A total of 60 meat and meat product samples, including minced meat, mutton, beef, chicken, hamburgers, and sausages, were collected from slaughterhouses, butchers, and restaurants in the Markazi province of Iran. The samples were analyzed using standard microbiological protocols for the isolation and characterization of Actinomycetes. PCR amplification of hsp65 and 16SrRNA genes and sequence analysis of 16SrRNA were used for genus and species identification. The minimum inhibitory concentrations (MICs) of antimicrobial agents were determined by the broth microdilution method and interpreted according to the CLSI guidelines.
RESULTS
A total of 21 (35%) Actinomycetes isolates from 5 genera and 12 species were isolated from 60 samples. The most prevalent Actinomycetes were from the genus , with six (28.6%) isolates (, , , and ), followed by the genus with five (23.8%) isolates ( and ), the genus Actinomyces with four (19.1%) isolates (), the genus with four (19.1%) isolates (, , and ), and the genus with two (9.5%) isolates (). Chicken and sausage samples had the highest and lowest levels of contamination, with six and one isolates. Respectively, the results of drug susceptibility testing (DST) showed that all isolates were susceptible to Ofloxacin, Amikacin, Ciprofloxacin, and Levofloxacin, whereas all of them were resistant to Doxycycline and Rifampicin.
DISCUSSION
The findings suggest that meat and meat products play an important role as a reservoir for the transmission of Actinomycetes to humans, thus causing life-threatening foodborne diseases such as gastrointestinal and cutaneous disorders. Therefore, it is essential to incorporate basic hygiene measures into the cycle of meat production to ensure food safety.
PubMed: 37520382
DOI: 10.3389/fmicb.2023.1134368 -
The Canadian Journal of Infectious... 2022In dental treatments, the reason for secondary caries and the failure of root canal treatment is the microbial infection, which concerns most dentists. The challenge of...
INTRODUCTION
In dental treatments, the reason for secondary caries and the failure of root canal treatment is the microbial infection, which concerns most dentists. The challenge of how to reduce the number of bacteria at the filling materials and the number of residual bacteria in the root canal has become a research hotspot. In this study, the bacterial adhesion properties of several common dental materials were compared to provide a theoretical basis for the selection of antibacterial properties of dental materials. . Three commonly used dental restorative materials and five sealers in root canal treatment were selected. Each material block was immersed in the corresponding supragingival ( and ) or subgingival ( and ) bacterial solution and cultured under anaerobic conditions at 37°C for 2, 4, 6, 8, 12, 16, 20, and 24 h. The adhesion of bacteria was observed, and the number of different bacteria adhering to various material model disks was calculated at different time intervals under a scanning electron microscope. The adherent CFU load of the materials was determined by colony counting.
RESULTS
and exhibited the strongest adhesion ability to the resin material blocks. and exhibited the highest adhesion ability to the AH-Plus sealer block.
CONCLUSIONS
In dental treatments, dental materials should be selected based on the chemical, physical, and biological properties of materials. In addition, it is necessary to develop new antibacterial dental materials.
PubMed: 35959001
DOI: 10.1155/2022/9595067 -
Microbiology Spectrum Aug 2022The cross-kingdom interactions between Candida albicans and Actinomyces viscosus play critical roles in root caries. However, the key pathway by which C. albicans...
The cross-kingdom interactions between Candida albicans and Actinomyces viscosus play critical roles in root caries. However, the key pathway by which C. albicans regulates its interactions with A. viscosus is unclear. Here, we first employed 39 volunteers with root caries and 37 caries-free volunteers, and found that the abundances of C. albicans and A. viscosus were significantly increased in the individuals with root caries and showed a strong positive correlation. Their dual-species combination synergistically promoted biofilm formation and root caries in rats. The arginine biosynthesis pathway of C. albicans was significantly upregulated in dual-species biofilms and dental plaques from another 10 root caries volunteers compared with the 10 caries-free volunteers. The exogenous addition of arginine increased the cariogenicity of the dual-species biofilm. The C. albicans , a key gene from the arginine biosynthesis pathway, null mutant failed to promote dual-species biofilm formation and root caries in rats; however, the addition of arginine restored its synergistic actions with A. viscosus. Our results identified the critical roles of the C. albicans arginine biosynthesis pathway in its cross-kingdom interactions with A. viscosus for the first time and indicated that targeting this pathway was a practical way to treat root caries caused by multiple species. Root caries is a critical problem that threatens the oral health of the elderly population. Our results identified the essential roles of the C. albicans arginine biosynthesis pathway in its cross-kingdom interactions with A. viscosus in root caries for the first time and indicated that targeting this pathway was a practical way to treat root caries caused by multiple species.
Topics: Actinomyces viscosus; Aged; Animals; Arginine; Biofilms; Candida albicans; Dental Caries; Humans; Rats; Root Caries
PubMed: 35862976
DOI: 10.1128/spectrum.00782-22 -
Polish Journal of Microbiology 2018This study compared the outcome of photosensitization on the viability of four different cariogens in planktonic form as well as biofilms in human dentine. Photodynamic... (Comparative Study)
Comparative Study
This study compared the outcome of photosensitization on the viability of four different cariogens in planktonic form as well as biofilms in human dentine. Photodynamic therapy was carried out with a gallium aluminium arsenide laser (670 nm wavelength) using Toluidine blue O (TBO) as the photosensitizer. Cariogenic bacteria ( Streptococcus mutans , Lactobacillus casei , Streptococcus salivarius and Actinomyces viscosus ) were exposed to TBO and then to the laser for 1 minute in planktonic suspension. Then, tooth slices previously incubated for 24 hours with broth cultures of broth culture of the four cariogenic organisms were exposed to antimicrobial photosensitization. The control samples consisted of planktonic and sessile cells that were exposed to TBO alone, laser alone and the bacterial cells that were not treated with TBO or laser. The results showed significant reductions in the viability of S. mutans , L. casei and A. viscosus in both planktonic form (to 13%, 30%, and 55%, respectively) and sessile form hosted in dentinal tubules (to 19%, 13% and 52%, respectively), relative to the controls. S. salivarius was the least affected in planktonic (94% viability) and sessile form (86% viability). In conclusion, sensitivity to photosensitization is species-dependent and sessile biofilm cells are affected to the same extent as their planktonic counterparts. This study compared the outcome of photosensitization on the viability of four different cariogens in planktonic form as well as biofilms in human dentine. Photodynamic therapy was carried out with a gallium aluminium arsenide laser (670 nm wavelength) using Toluidine blue O (TBO) as the photosensitizer. Cariogenic bacteria (, , and ) were exposed to TBO and then to the laser for 1 minute in planktonic suspension. Then, tooth slices previously incubated for 24 hours with broth cultures of broth culture of the four cariogenic organisms were exposed to antimicrobial photosensitization. The control samples consisted of planktonic and sessile cells that were exposed to TBO alone, laser alone and the bacterial cells that were not treated with TBO or laser. The results showed significant reductions in the viability of , and in both planktonic form (to 13%, 30%, and 55%, respectively) and sessile form hosted in dentinal tubules (to 19%, 13% and 52%, respectively), relative to the controls. was the least affected in planktonic (94% viability) and sessile form (86% viability). In conclusion, sensitivity to photosensitization is species-dependent and sessile biofilm cells are affected to the same extent as their planktonic counterparts.
Topics: Adult; Biofilms; Dental Caries; Humans; Lacticaseibacillus casei; Microbial Viability; Photochemotherapy; Photosensitizing Agents; Streptococcus mutans; Streptococcus salivarius; Tolonium Chloride; Tooth; Young Adult
PubMed: 30550231
DOI: 10.21307/pjm-2018-053 -
Journal of Oral and Maxillofacial... 2019The Ayurvedic system of medicine is popular in India and has gone through various change and remains as the mainstay of medical relief to a large population. Dental...
INTRODUCTION
The Ayurvedic system of medicine is popular in India and has gone through various change and remains as the mainstay of medical relief to a large population. Dental caries is the one of the major issue in the recent time, and there is no definite caries prevention method so far apart from Topical fluoride application, regular oral hygiene measures, pit and fissure sealants and diet measure. In spite of the above mentioned preventive measures the people are still prone to dental caries. In order to find a better solution the present study evaluates the antimicrobial properties widely available and cost effective herbal extracts of Solanum xanthocarpum and Pistacia lentiscus extract on cariogenic oral microbial flora.
AIM
To Evaluate the Antimicrobial properties of Solanum xanthocarpum and Pistacia lentiscus extracts on cariogenic oral microbial flora.
METHODOLOGY
The antimicrobial properties of Solanum xanthocarpum and Pistacia lentiscus extracts on cariogenic oral microbial flora (streptococcus mutans, lactobacillus, actinomyces viscosus) by different culture techniques to estimate the zone of inhibition (well diffusion method) and minimum inhibitory concentration (tube dilution method).
RESULTS
The antimicrobial efficacy of Solanum xanthocarpum and Pistacia lentiscus on test bacteria were analysed using kurskal wallis test and values of 0.003 and 0.002 were obtained respectively, since the values were less than 0.005, indicating that both herbal products possess statistically significant antimicrobial properties.
CONCLUSION
The antimicrobial effects of the herbal extracts were almost on par with commercially available allopathic agents like chlorhexidine on oral cariogenic microbes. The efficacy should be further validated in a large scale studies and can be utilized for caries prevention in the form of mouth rinses, dentifrices and topical application in the future.
PubMed: 31942118
DOI: 10.4103/jomfp.JOMFP_30_19