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Background: Streptococcus salivarius is an opportunistic pathogen, and there have been no reported cases of Streptococcus salivarius pneumonia to date. Pneumomediastinum is usually secondary to tracheal or esophageal injury and is very rare as a complication of pneumonia. We report a case of Streptococcus salivarius pneumonia complicated by pneumomediastinum, aiming to enhance clinicians' awareness of rare pathogens and uncommon complications in pneumonia. Case presentation: The patient, a 36-year-old male, presented with a persistent cough and sputum production for one week, accompanied by a sore throat that had developed just one day prior. Chest computed tomography (CT) disclosed pneumomediastinum alongside obstructive atelectasis in the left lower lobe. Streptococcus salivarius infection was conclusively identified through bronchoalveolar lavage metagenomic next-generation sequencing (mNGS), as well as smear and culture analyses. The patient was administered intravenous amoxicillin-clavulanate potassium for a duration of seven days as part of the anti-infection regimen. Given the stability of the patient's respiratory and circulatory systems, a tube drainage procedure was deemed unnecessary. Post-treatment, the patient's clinical symptoms notably improved. A subsequent chest CT scan revealed the re-expansion of the left lower lung and near-complete resolution of pneumomediastinum. Conclusion: There are numerous pathogens that can cause pneumonia. While focusing on common pathogens, it is important not to overlook rare ones. When considering infections from rare pathogens, it is recommended to promptly perform a bronchoscopy and submit bronchoalveolar lavage fluid for mNGS to improve pathogen detection rates. During the diagnosis and treatment of pneumonia, it is crucial to be vigilant for rare complications. When a patient presents with symptoms such as dyspnea or subcutaneous emphysema, it is advisable to immediately perform a chest CT scan to rule out pneumomediastinum. [ABSTRACT FROM AUTHOR]

This study investigates the efficacy of Streptococcus salivarius K12 in preventing upper respiratory tract infections (URTIs) in healthy adults. URTIs are a common issue, particularly in physically active individuals, leading to significant disruptions in daily life. Probiotics, such as S. salivarius K12, have emerged as a potential preventive strategy for these infections. This research was conducted as a randomized, double-blind, placebo-controlled trial involving 112 participants aged between 19 and 25. Participants were randomly divided into two groups: one group received a daily dose of S. salivarius K12, marketed as Bactoblis®, while the other received a placebo. The trial lasted for four months, during which adherence to the treatment protocol was closely monitored. The primary goal was to measure the incidence of URTIs using the Jackson Scale and the Wisconsin Upper Respiratory Symptom Survey (WURSS-11). The results indicated that higher adherence to the S. salivarius K12 treatment was associated with an increased number of days without URTI symptoms. Although the overall severity of symptoms did not differ significantly between the treatment and control groups, those with high adherence to S. salivarius K12 (greater than 90%) reported more days free from illness. In conclusion, S. salivarius K12 demonstrated potential as a preventive measure against URTIs, especially in individuals who adhered strictly to the treatment regimen. However, further research involving larger populations and longer follow-up periods is needed to fully confirm these findings and better understand the role of S. salivarius K12 in preventing respiratory infections. [ABSTRACT FROM AUTHOR]

Abstract Background Streptococcus salivarius is an opportunistic pathogen, and there have been no reported cases of Streptococcus salivarius pneumonia to date. Pneumomediastinum is usually secondary to tracheal or esophageal injury and is very rare as a complication of pneumonia. We report a case of Streptococcus salivarius pneumonia complicated by pneumomediastinum, aiming to enhance clinicians’ awareness of rare pathogens and uncommon complications in pneumonia. Case presentation The patient, a 36-year-old male, presented with a persistent cough and sputum production for one week, accompanied by a sore throat that had developed just one day prior. Chest computed tomography (CT) disclosed pneumomediastinum alongside obstructive atelectasis in the left lower lobe. Streptococcus salivarius infection was conclusively identified through bronchoalveolar lavage metagenomic next-generation sequencing (mNGS), as well as smear and culture analyses. The patient was administered intravenous amoxicillin-clavulanate potassium for a duration of seven days as part of the anti-infection regimen. Given the stability of the patient’s respiratory and circulatory systems, a tube drainage procedure was deemed unnecessary. Post-treatment, the patient’s clinical symptoms notably improved. A subsequent chest CT scan revealed the re-expansion of the left lower lung and near-complete resolution of pneumomediastinum. Conclusion There are numerous pathogens that can cause pneumonia. While focusing on common pathogens, it is important not to overlook rare ones. When considering infections from rare pathogens, it is recommended to promptly perform a bronchoscopy and submit bronchoalveolar lavage fluid for mNGS to improve pathogen detection rates. During the diagnosis and treatment of pneumonia, it is crucial to be vigilant for rare complications. When a patient presents with symptoms such as dyspnea or subcutaneous emphysema, it is advisable to immediately perform a chest CT scan to rule out pneumomediastinum.

Synbiotics are mixtures of prebiotics and probiotics that enhance the activity of probiotic bacteria when co-administered to provide greater benefits to the host. Traditionally, the synbiotics that have been discovered enhance gut probiotic strains and are nutritionally complex molecules that survive digestive breakdown until they reach the later stages of the intestinal tract. Here, we screened and identified sugars or sugar substitutes as synbiotics for the oral probiotic strains Streptococcus salivarius BLIS K12 and BLIS M18. Using a modified deferred antagonism assay, we found that 0.5% (w/v) galactose and 2.5% (w/v) raffinose were the best candidates for use as synbiotics with BLIS K12 and M18, as they trigger enhanced antimicrobial activity against a range of bacteria representing species from the mouth, gut, and skin. Using reverse transcriptase quantitative PCR, we found that this enhanced antimicrobial activity was caused by the upregulation of the lantibiotic genes salA, salB, and sal9 in either K12 or M18. This led to the conclusion that either 2.5% (w/v) raffinose or 0.5% (w/v) galactose, respectively, are suitable synbiotics for use in conjunction with BLIS K12 and M18 to enhance probiotic performance.

Synbiotics are mixtures of prebiotics and probiotics that enhance the activity of probiotic bacteria when co-administered to provide greater benefits to the host. Traditionally, the synbiotics that have been discovered enhance gut probiotic strains and are nutritionally complex molecules that survive digestive breakdown until they reach the later stages of the intestinal tract. Here, we screened and identified sugars or sugar substitutes as synbiotics for the oral probiotic strains Streptococcus salivarius BLIS K12 and BLIS M18. Using a modified deferred antagonism assay, we found that 0.5% (w/v) galactose and 2.5% (w/v) raffinose were the best candidates for use as synbiotics with BLIS K12 and M18, as they trigger enhanced antimicrobial activity against a range of bacteria representing species from the mouth, gut, and skin. Using reverse transcriptase quantitative PCR, we found that this enhanced antimicrobial activity was caused by the upregulation of the lantibiotic genes salA, salB, and sal9 in either K12 or M18. This led to the conclusion that either 2.5% (w/v) raffinose or 0.5% (w/v) galactose, respectively, are suitable synbiotics for use in conjunction with BLIS K12 and M18 to enhance probiotic performance. [ABSTRACT FROM AUTHOR]

Statement of the Problem: Dental caries and periodontal disease are the most common oral problems. Chemical antibacterial agents often have side effects; thus, researchers have long been in search for organic and herbal products to prevent dental caries and periodontal disease. Purpose: The present study has aimed to assess the effects of Dracocephalum moldavica essential oil on Streptococcus mutans, Streptococcus salivarius, Streptococcus sobrinus, and Lactobacillus acidophilus compared to Chlorhexidine (CHX). Materials and Method: In this in vitro study, the plants were collected from Zanjan Province, Iran. Analysis of the essential oil was carried out by gas chromatography/mass chromatography. Micro-broth dilution and disc diffusion methods were used for assessment of the antimicrobial activity, and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated. Results: The mean diameter of the growth inhibition zones in the well plate method for Dracocephalum moldavica showed that it had greater antimicrobial activity against Lactobacillus acidophilus than others (p Value= 0.01). Furthermore, Dracocephalum moldavica had higher antimicrobial activity than CHX. The results of MIC and MBC showed that Dracocephalum moldavica had lower antibacterial activity than CHX. Conclusion: Dracocephalum moldavica essential oil demonstrated antibacterial properties against cariogenic bacteria. Given that other favorable properties of these essential oils are confirmed, they may be suitable for use as antibacterial agents in the formulation of oral healthcare products. [ABSTRACT FROM AUTHOR]

Background: Clinical trials investigating the efficacy of oral health prevention materials have conventionally used indices to evaluate the amount of plaque on tooth surfaces. Various methods, including the use of probiotics, have been suggested to prevent oral disease. The present study was conducted to investigate the probiotic products available in Iranian pharmacies that are used for the prevention of dental disease. Materials and Methods: In this double-blind randomized clinical trial, 40 students of medicine and pharmacy were randomly allocated into two equal groups of intervention and control using random allocation software. The intervention group used a probiotic pill containing Streptococcus salivarius M18 and K12 bacteria every night before going to bed. The control group used a mouth freshener tablet with the same flavor as the probiotic tablet every night before going to bed. The mean number of Streptococcus mutans bacteria in both the groups was calculated before and after using probiotic pills. The data were staticali analyzed by descriptive statistics (central tendency and dispersion) and inferential statistics (paired t-test and independent t-test) and Kolmogorov-Smironove tests (P<0.05). Results: The plaque index values at the beginning of the study showed no statistical differences between the intervention and control groups (P = 0.85).The plaque index values in the intervention group before and after the intervention were 0.4I and 0.75, respectively, which showed a statistically significant difference (P < 0.05). The plaque index values in the control group before and after the intervention were 0.42 and 0.42, respectively, which indicated no statistically significant difference (P > 0.05). Conclusion: The mean plaque index in the group using probiotic tablets was significantly increased compared to those of the control group. However, further studies are suggested to evaluate these products. [ABSTRACT FROM AUTHOR]

Background: Various methods, including the use of probiotics, have been suggested to prevent caries. Caries, which is mainly caused by Streptococcus mutans, is one of the bacterial diseases that imposes a heavy cost on society. The present study was conducted to investigate the probiotic products available in Iranian pharmacies that are used for caries prevention. Materials and Methods: In this double-blind randomized clinical trial, 40 students of medicine and pharmacy were randomly allocated to two equal groups of intervention and control using random allocation software. The intervention group used a probiotic pill containing Streptococcus salivarius MI8 and KI2 bacteria every night before going to bed. The control group used a mouth freshener tablet with the same flavor as the probiotic tablet every night before going to bed. The data were analyzed by SPSS (version 24) software using descriptive statistics (central tendency and dispersion) and inferential statistics (paired t-test and independent t-test). Data were collected using Excel software, and statistical analyses were performed by SPSS software (version 24). Results: The mean number of S. mutans in the intervention group was 754.5 cfu/mm before the intervention and 1701.5 cfu/mm after the intervention, which showed a statistically significant difference (P < 0.05). In the control group, the mean S. mutans was 683 cfu/mm at the beginning of the intervention and 659 cfu/mm at the end of the intervention, which did not indicate a statistically significant difference (P > 0.05). Moreover, the normality of data was checked by the Kolmogorov-Smirnov test. Conclusion: The mean number of S. mutans bacteria in the group using probiotic tablets was significantly increased compared to those of the control group. However, further studies are suggested to evaluate these products. [ABSTRACT FROM AUTHOR]

Background. In recent years, fluoride concentrations in toothpaste for children and adults have increased. However, the effects of different concentrations on bacterial activity have rarely been compared. We aimed to investigate and compare the antibacterial activity of children’s and adults’ toothpaste containing 500, 1000‒1100, and 1450‒1500 ppm fluoride. Methods. Three strains of bacteria (Streptococcus mutans, Streptococcus salivarius, and Lactobacillus casei) were cultured in brain heart infusion agar. Thirty commercially available toothpaste products for children and adults containing 500, 1000‒1100, and 1450‒1500 ppm fluoride were selected and tested. Toothpaste’s ability to inhibit bacterial growth was evaluated by agar diffusion assay, in which plates were incubated for 24 hours, and then the diameter of the microbial inhibition zone was measured. Comparisons between children’s and adults’ fluoride toothpastes were made using the Mann-Whitney U test. The association between bacterial growth inhibition and sodium lauryl sulfate (SLS) was analyzed by the chi-square test. A P value of

This study investigates the efficacy of Streptococcus salivarius K12 in preventing upper respiratory tract infections (URTIs) in healthy adults. URTIs are a common issue, particularly in physically active individuals, leading to significant disruptions in daily life. Probiotics, such as S. salivarius K12, have emerged as a potential preventive strategy for these infections. This research was conducted as a randomized, double-blind, placebo-controlled trial involving 112 participants aged between 19 and 25. Participants were randomly divided into two groups: one group received a daily dose of S. salivarius K12, marketed as Bactoblis®, while the other received a placebo. The trial lasted for four months, during which adherence to the treatment protocol was closely monitored. The primary goal was to measure the incidence of URTIs using the Jackson Scale and the Wisconsin Upper Respiratory Symptom Survey (WURSS-11). The results indicated that higher adherence to the S. salivarius K12 treatment was associated with an increased number of days without URTI symptoms. Although the overall severity of symptoms did not differ significantly between the treatment and control groups, those with high adherence to S. salivarius K12 (greater than 90%) reported more days free from illness. In conclusion, S. salivarius K12 demonstrated potential as a preventive measure against URTIs, especially in individuals who adhered strictly to the treatment regimen. However, further research involving larger populations and longer follow-up periods is needed to fully confirm these findings and better understand the role of S. salivarius K12 in preventing respiratory infections.

Background: Clinical trials investigating the efficacy of oral health prevention materials have conventionally used indices to evaluate the amount of plaque on tooth surfaces. Various methods, including the use of probiotics, have been suggested to prevent oral disease. The present study was conducted to investigate the probiotic products available in Iranian pharmacies that are used for the prevention of dental disease. Materials and Methods: In this double-blind randomized clinical trial, 40 students of medicine and pharmacy were randomly allocated into two equal groups of intervention and control using random allocation software. The intervention group used a probiotic pill containing Streptococcus salivarius M18 and K12 bacteria every night before going to bed. The control group used a mouth freshener tablet with the same flavor as the probiotic tablet every night before going to bed. The mean number of Streptococcus mutans bacteria in both the groups was calculated before and after using probiotic pills. The data were staticali analyzed by descriptive statistics (central tendency and dispersion) and inferential statistics (paired t-test and independent t-test) and Kolmogorov-Smironove tests (P 0.05). Conclusion: The mean plaque index in the group using probiotic tablets was significantly increased compared to those of the control group. However, further studies are suggested to evaluate these products.

Background: Various methods, including the use of probiotics, have been suggested to prevent caries. Caries, which is mainly caused by Streptococcus mutans, is one of the bacterial diseases that imposes a heavy cost on society. The present study was conducted to investigate the probiotic products available in Iranian pharmacies that are used for caries prevention. Materials and Methods: In this double-blind randomized clinical trial, 40 students of medicine and pharmacy were randomly allocated to two equal groups of intervention and control using random allocation software. The intervention group used a probiotic pill containing Streptococcus salivarius M18 and K12 bacteria every night before going to bed. The control group used a mouth freshener tablet with the same flavor as the probiotic tablet every night before going to bed. The data were analyzed by SPSS (version 24) software using descriptive statistics (central tendency and dispersion) and inferential statistics (paired t-test and independent t-test). Data were collected using Excel software, and statistical analyses were performed by SPSS software (version 24). Results: The mean number of S. mutans in the intervention group was 754.5 cfu/mm before the intervention and 1701.5 cfu/mm after the intervention, which showed a statistically significant difference (P < 0.05). In the control group, the mean S. mutans was 683 cfu/mm at the beginning of the intervention and 659 cfu/mm at the end of the intervention, which did not indicate a statistically significant difference (P > 0.05). Moreover, the normality of data was checked by the Kolmogorov–Smirnov test. Conclusion: The mean number of S. mutans bacteria in the group using probiotic tablets was significantly increased compared to those of the control group. However, further studies are suggested to evaluate these products.

Streptococcus salivarius (S. salivarius) K12 supplementation has been found to reduce the risk of recurrent upper respiratory tract infections. Yet, studies have not reported the effect of supplementation on oral S. salivarius K12 levels or the salivary microbiome. This clinical trial was designed to determine how supplementation with S. salivarius K12 influences the oral microbiome. In a randomized, double-blind, placebo-controlled trial, 13 healthy adults received a probiotic powder (PRO) containing Lactobacillus acidophilus, Bifidobacterium lactis, and S. salivarius K12 and 12 healthy adults received a placebo-control powder (CON) (n = 12) for 14 consecutive days. Oral S. salivarius K12 and total bacteria were quantified by qPCR and the overall oral microbiome was measured using 16S rRNA amplicon sequencing. Supplementation significantly increased mean salivary S. salivarius K12 levels by 5 logs compared to baseline for the PRO group (p < 0.0005), which returned to baseline 2 weeks post-supplementation. Compared with the CON group, salivary S. salivarius K12 was 5 logs higher in the PRO group at the end of the supplementation period (p < 0.001). Neither time nor supplementation influenced the overall oral microbiome. Supplementation with a probiotic cocktail containing S. salivarius K12 for two weeks significantly increased levels of salivary S. salivarius K12.

Some species of oral bacteria can reduce dietary nitrate to nitrite, which can later be converted to nitric oxide in the nitrate—nitrite—nitic oxide pathway. Increasing nitric oxide availability can reduce blood pressure (BP) and improve exercise performance. Streptococcus salivarius M18 (Streptococcus salivarius M18) is a bacteriocin-producing probiotic that is known to improve oral health by inhibiting pathogenic oral bacteria. However, it is presently unclear whether probiotic-induced alterations to the oral microbiome will influence circulating levels of nitric oxide metabolites and BP. Purpose: To determine the effects of Streptococcus salivarius M18 supplementation on plasma and salivary nitrate and nitrite levels and BP. Methods: Ten healthy males (age 32 ± 8 y, body mass 88.2 ± 15.1 kg) completed 2 × 14-day supplementation phases in a randomized order at least 14 days apart. In one phase, participants consumed Streptococcus salivarius M18 probiotic lozenges (2.5 billion colony-forming units/dose) once per day, and in the other, they ingested water (placebo). The abundance of bacteria on the tongue was assessed via Illumina 16S rRNA gene sequencing, unstimulated saliva, and venous blood samples were collected, and BP was measured pre and post each phase. Saliva and plasma were analysed for nitrate and nitrite using chemiluminescence, and pH was measured in saliva. The change in each outcome from pre- to post-supplementation was compared between phases using repeated measures ANOVA. Results: Plasma nitrite increased from baseline following probiotic supplementation (from 173 ± 39 to 223 ± 63 nM, p = 0.003, 95% CI 192–250 nM). In comparison, there was no change in the placebo phase or between baselines (all p > 0.05). The abundance of nitrite-producing bacteria was not altered, salivary nitric oxide metabolites and pH did not change, and the increase in plasma nitrite did not result in reductions in BP (all p > 0.05). Conclusions: Supplementation with Streptococcus salivarius M18 increased plasma nitrite, a key marker of NO availability. Despite this, Streptococcus salivarius M18 did not lower BP in these healthy normotensive participants. Additionally, the increase in plasma nitrite was not associated with abundance changes in bacteria thought important to NO generation. Further research is required to determine the mechanism behind the increase in plasma nitrite and the potential therapeutic and ergogenic benefits of Streptococcus salivarius M18 supplementation. [ABSTRACT FROM AUTHOR]

Objectives: This study presents results of our randomized clinical trial studying the effect of human probiotics on memory and psychological and physical measures following our study protocol registered at clinicaltrials.gov NCT05051501 and described in detail in our previous paper. Methods: Community dwelling participants aged between 55 and 80 years were randomly assigned to receive a single dose of 106 colony-forming units of human Streptococcus thermophilus GH, Streptococcus salivarius GH NEXARS, Lactobacilus plantarum GH, and Pediococcus pentosaceus GH or placebo. A cross-over design allowed each group to receive probiotics and placebo for 3 months each in reverse order. A small subset of participants was examined online due to the COVID-19 pandemic. After 6 months a small number of volunteers were additionally assessed after 2 months without any intervention. Primary outcome measures included changes in cognitive functions assessed using brief tests and a neuropsychological battery and changes in mood assessed using validated questionnaires. Secondary outcome measures included changes in self-report and subjective measures using depression and anxiety questionnaires, seven visual analog scales of subjective feelings (memory, digestion, etc.), and physical performance. Results: At baseline, the probiotic-placebo group A (n = 40, age 69 ± 7 years, education 16 ± 3 years, 63% females, body mass index 28.5 ± 6, subjective memory complaint in 43%) did not differ from the placebo-probiotic group B (n = 32) in any of the sociodemographic characteristics and evaluated measures including cognitive status. At follow-up visits after 3, 6, and 8 months, no cross-sectional differences in any of the measures were found between the groups except worse sentence recall of the ALBA test after 3 months of probiotic use. Score changes were not observed for all cognitive tests but one in any group between visits 1 and 3 and between visits 3 and 6. The only change was observed for the TMT B test after the first three months but no change was observed after the second three months. Conclusion: The treatment with human probiotics and prebiotics did not improve cognitive, affective, or physical measures in community-dwelling individuals with normal or mildly impaired cognitive functions. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa dominates the complex polymicrobial cystic fibrosis (CF) airway and is a leading cause of death in persons with CF. Interestingly, oral streptococcal colonization has been associated with stable CF lung function. The most abundant streptococcal species found in stable patients, Streptococcus salivarius, has been shown to downregulate pro-inflammatory cytokines in multiple colonization models. However, no studies have demonstrated how S. salivarius potentially improves lung function. Our lab previously demonstrated that the P. aeruginosa exopolysaccharide Psl promotes S. salivarius biofilm formation in vitro, suggesting a possible mechanism by which S. salivarius is incorporated into the CF airway microbial community. In this study, we demonstrate that co-infection of rats leads to enhanced S. salivarius colonization and reduced P. aeruginosa colonization. Histological scores for tissue inflammation and damage are lower in dual-infected rats compared to P. aeruginosa infected rats. Additionally, pro-inflammatory cytokines IL-1β, IL-6, CXCL2, and TNF-α are downregulated during co-infection compared to P. aeruginosa single-infection. Lastly, RNA sequencing of cultures grown in synthetic CF sputum revealed that P. aeruginosa glucose metabolism genes are downregulated in the presence of S. salivarius, suggesting a potential alteration in P. aeruginosa fitness during co-culture. Overall, our data support a model in which S. salivarius colonization is promoted during co-infection with P. aeruginosa, whereas P. aeruginosa airway bacterial burden is reduced, leading to an attenuated host inflammatory response. [ABSTRACT FROM AUTHOR]

Background: White spot lesions (WSLs) are a formidable challenge during orthodontic treatment, affecting patients regardless of oral hygiene. Multifactorial in nature, amongst potential contributors to their development are the microbiome and salivary pH. The aim of our pilot study is to determine if pre-treatment differences in salivary Stephan curve kinetics and salivary microbiome features correlate with WSL development in orthodontic patients with fixed appliances. We hypothesize that non-oral hygiene determined differences in saliva could be predictive of WSL formation in this patient population through analysis of salivary Stephan curve kinetics, and that these differences would further manifest as changes in the oral microbiome. Methods: In this prospective cohort study, twenty patients with initial simplified oral hygiene index scores of "good" that were planning to undergo orthodontic treatment with self-ligating fixed appliances for at least 12 months were enrolled. At pre-treatment stage, saliva was collected for microbiome analysis, and at 15-minute intervals after a sucrose rinse over 45 min for Stephan curve kinetics. Results: 50% of patients developed a mean 5.7 (SEM: 1.2) WSLs. There were no differences in saliva microbiome species richness, Shannon alpha diversity or beta diversity between the groups. Capnocytophaga sputigena exclusively and Prevotella melaninogenica predominantly were found in WSL patients, while Streptococcus australis was negatively correlated with WSL development. Streptococcus mitis and Streptococcus anginosus were primarily present in healthy patients. There was no evidence to support the primary hypothesis. Conclusions: While there were no differences in salivary pH or restitution kinetics following a sucrose challenge and no global microbial differences in WSL developers, our data showed change in salivary pH at 5 min associated with an abundance of acid-producing bacteria in saliva. The results suggest salivary pH modulation as a management strategy to inhibit the abundance of caries initiators. Our study may have uncovered the earliest predecessors to WSL/caries development. [ABSTRACT FROM AUTHOR]

Oral mucosal infection, especially oral candidiasis, is currently the most common oral mucosal disease. Traditional drug treatment regimens have difficulty adhering to mucous membranes, coupled with the unique anatomical and physiological characteristics of the oral cavity, thus reducing drug availability and limiting the effective time of drug action. Inspired by cell membrane-coated nanoparticles, this study aimed to construct a bionic adherent oral mucosal drug delivery system and investigated its therapeutic potential for oral candidiasis. The system was obtained by encapsulating Streptococcus salivarius K12 membranes on triclosan-loaded PLGA nanoparticles using an extrusion method. The constructed nanocomplexes (K12/TCS@PLGA-NPs) inherited the properties of the source cell membrane, bionically adhering to the oral mucosa and binding to the candida albicans hypha. Our in vitro and in vivo experiments have confirmed that K12/TCS@PLGA-NPs nanocomplexes significantly inhibits the formation of C. albicans biofilms and the development of oral candidiasis by enhancing the accumulation of drugs in lesions, optimizing drug efficacy. Furthermore, the biomimetic nanocomplexes could be considered safe and effective drug delivery systems, which hold considerable therapeutic promise for oral mucosal infections including candidiasis.

SARS-CoV-2 infection can cause changes in the organs and tissues of the oral cavity, which is associated with a wide distribution of angiotensin-converting enzyme type 2 in the oral cavity, mainly epithelial cells of the oral mucosa, gums and fibroblasts of the periodontal ligament. Thus, the oral mucosa is susceptible to SARS-CoV-2 infection and may act as a gateway for the virus, as well as a reservoir for SARS-CoV-2. We searched the literature for the period from the beginning of the pandemic until May 30, 2022, devoted to the study of changes in the organs and tissues of the oral cavity with a new coronavirus infection (COVID-19) in the electronic search engines PubMed/MEDLINE and Scopus. A special place in the study of changes in the organs and tissues of the oral cavity with a new coronavirus infection (COVID-19) is occupied by periodontal pathology. A number of reviews and clinical studies conclude the importance of good oral hygiene and periodontal health as an important aspect of COVID-19 prevention and management. Oral probiotics can be considered as a promising direction for correcting changes in organs and tissues of the oral cavity in COVID-19.

Pseudomonas aeruginosa dominates the complex polymicrobial cystic fibrosis (CF) airway and is a leading cause of death in persons with CF. Interestingly, oral streptococcal colonization has been associated with stable CF lung function. The most abundant streptococcal species found in stable patients, Streptococcus salivarius, has been shown to downregulate pro-inflammatory cytokines in multiple colonization models. However, no studies have demonstrated how S. salivarius potentially improves lung function. Our lab previously demonstrated that the P. aeruginosa exopolysaccharide Psl promotes S. salivarius biofilm formation in vitro, suggesting a possible mechanism by which S. salivarius is incorporated into the CF airway microbial community. In this study, we demonstrate that co-infection of rats leads to enhanced S. salivarius colonization and reduced P. aeruginosa colonization. Histological scores for tissue inflammation and damage are lower in dual-infected rats compared to P. aeruginosa infected rats. Additionally, pro-inflammatory cytokines IL-1β, IL-6, CXCL2, and TNF-α are downregulated during co-infection compared to P. aeruginosa single-infection. Lastly, RNA sequencing of cultures grown in synthetic CF sputum revealed that P. aeruginosa glucose metabolism genes are downregulated in the presence of S. salivarius, suggesting a potential alteration in P. aeruginosa fitness during co-culture. Overall, our data support a model in which S. salivarius colonization is promoted during co-infection with P. aeruginosa, whereas P. aeruginosa airway bacterial burden is reduced, leading to an attenuated host inflammatory response.

The human oral cavity contains a diversity of microbial habitats that have been adopted and adapted to as homeland by an amazingly heterogeneous population of microorganisms collectively referred to as the oral microbiota. These microbes generally co-habit in harmonious homeostasis. However, under conditions of imposed stress, as with changes to the host's physiology or nutritional status, or as a response to foreign microbial or antimicrobial incursions, some components of the oral "microbiome" (viz. the in situ microbiota) may enter a dysbiotic state. This microbiome dysbiosis can manifest in a variety of guises including streptococcal sore throats, dental caries, oral thrush, halitosis and periodontal disease. Most of the strategies currently available for the management or treatment of microbial diseases of the oral cavity focus on the repetitive "broad sweep" and short-term culling of oral microbe populations, hopefully including the perceived principal pathogens. Both physical and chemical techniques are used. However, the application of more focused approaches to the harnessing or elimination of key oral cavity pathogens is now feasible through the use of probiotic strains that are naturally adapted for oral cavity colonization and also are equipped to produce anti-competitor molecules such as the bacteriocins and bacteriocin-like inhibitory substances (viz BLIS). Some of these probiotics are capable of suppressing the proliferation of a variety of recognized microbial pathogens of the human mouth, thereby assisting with the restoration of oral microbiome homeostasis. BLIS K12 and BLIS M18, the progenitors of the BLISproducing oral probiotics, are members of the human oral cavity commensal species Streptococcus salivarius. More recently however, a number of other streptococcal and some non-streptococcal candidate oral probiotics have also been promoted. What is becoming increasingly apparent is that the future for oral probiotic applications will probably extend well beyond the attempted limitation of the direct pathological consequences of oral microbiome dysbiosis to also encompass a plethora of systemic diseases and disorders of the human host. The background to and the evolving prospects for the beneficial modulation of the oral microbiome via the application of BLIS-producing S. salivarius probiotics comprises the principal focus of the present review. [ABSTRACT FROM AUTHOR]

Introduction: Plaque accumulation on the surface of removable orthodontic appliances could lead to dental caries, periodontitis, and fungal infections. This study evaluated the effectiveness of antimicrobial photodynamic therapy (aPDT), chlorhexidine (CHX), sodium fluoride (NaF), and hydrogen peroxide (H2O2) for the disinfection of acrylic resin. Methods: In this in vitro experimental study, 100 acrylic resin specimens were randomly divided into five groups (n = 20 each): Enterococcus faecalis, Streptococcus mutans, Streptococcus salivarius, Streptococcus sanguinis, and Lactobacillus acidophilus. Each group was immersed separately in 5 mL of microbial suspension. They were then incubated until biofilm formation on their surface. Of each microorganism, one biofilm sample in phosphate-buffered saline was considered as negative control, and other biofilm samples (n = 80) were subjected to aPDT with curcumin, 0.12% CHX (positive control), 1% H2O2, and 0.2% NaF. Finally, the number of colonies was counted. Data were analyzed by the Kruskal-Wallis and Mann-Whitney tests, two-way ANOVA, and Bonferroni adjustment at a significance level of 0.05. Results: The interaction effect of the treatment modality and type of microorganism was significant on the microbial count (effect size: 0.91, P < 0.05). Maximum bacterial proliferation was noted in the following combinations: NaF/E. faecalis, H2O2/E. faecalis, and H2O2/S. salivarius. Microorganisms had no or insignificant growth and proliferation in the aPDT and CHX groups. Conclusion: The results supported the optimal antimicrobial efficacy of PDT which was comparable to that of CHX. aPDT showed superior antimicrobial efficacy to NaF and H2O2 for the disinfection of acrylic resin. [ABSTRACT FROM AUTHOR]

Statement of the Problem: There are global efforts for introducing a new herbal antimicrobial agent with minimal side effects. There are some reports about the antimicrobial properties of Pimpinella anisum and Oregano Vulgare. Purpose: In this study, the antimicrobial properties of Pimpinella anisum and Oregano Vulgare have been assessed. Material and Method: In this experimental in vitro study, the dental plaque samples were collected from children aged 3 to 5 years old who were referred to a private dental office with diagnosis of dental caries. After determination of the bacterial colonies of Streptococcus sanguinis, Streptococcus mutans and Streptococcus salivarius, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ethanolic and methanolic extracts of Pimpinella anisum and Oregano vulgare were measured by macrodilution and microdilution methods. Results: The mean MIC and MBC of Pimpinella anisum extract and Oregano vulgare extract and their combination against Streptococcus mutans, Streptococcus sanguinis, and Streptococcus salivarius were statistically different (p< 0.001). The combination of these extracts showed the lowest MIC and MBC. Conclusion: Hydroalcoholic extracts of the Pimpinella anisum and Oregano Vulgare were effective antibacterial agent against Streptococcus mutans, Streptococcus salivarius, and Streptococcus sanguinis so the combination of these two extracts showed the highest antibacterial properties on all the bacteria evaluated.

Aim: To evaluate and compare the effect of probiotic Streptococcus salivarius K12 and M18 on the Streptococcus mutans count, salivary pH and buffer capacity. Materials and method: 69 Subjects within the age group of 18-40 years were randomly allocated to three groups of 23 subjects each. Subjects enrolled in Group A received BLIS K12TM, Subjects in Group B received BLIS M18TM and Subjects in Group C belonged to the control group and did not receive any form of probiotics. Unstimulated salivary samples were collected at baseline and after 30 days. The samples were analysed for Streptococcus mutans level, salivary pH and buffer capacity. Results: A statistically significant reduction in salivary S. mutans levels and an increase in the salivary pH was observed after the use of probiotics when compared to the baseline. The buffer capacity remained unaltered following the use of both the probiotics. There was no change in the Streptococcus mutans level, salivary pH and buffer capacity for the subjects belonging to the control group. Conclusion: Within the limitations of the present study it can be concluded that a 30day use of Streptococcus salivarius K12 and M18 resulted in a reduction in the Streptococcus mutans count while simultaneously improving the salivary pH.

The human oral cavity contains a diversity of microbial habitats that have been adopted and adapted to as homeland by an amazingly heterogeneous population of microorganisms collectively referred to as the oral microbiota. These microbes generally co-habit in harmonious homeostasis. However, under conditions of imposed stress, as with changes to the host’s physiology or nutritional status, or as a response to foreign microbial or antimicrobial incursions, some components of the oral “microbiome” (viz. the in situ microbiota) may enter a dysbiotic state. This microbiome dysbiosis can manifest in a variety of guises including streptococcal sore throats, dental caries, oral thrush, halitosis and periodontal disease. Most of the strategies currently available for the management or treatment of microbial diseases of the oral cavity focus on the repetitive “broad sweep” and short-term culling of oral microbe populations, hopefully including the perceived principal pathogens. Both physical and chemical techniques are used. However, the application of more focused approaches to the harnessing or elimination of key oral cavity pathogens is now feasible through the use of probiotic strains that are naturally adapted for oral cavity colonization and also are equipped to produce anti-competitor molecules such as the bacteriocins and bacteriocin-like inhibitory substances (viz BLIS). Some of these probiotics are capable of suppressing the proliferation of a variety of recognized microbial pathogens of the human mouth, thereby assisting with the restoration of oral microbiome homeostasis. BLIS K12 and BLIS M18, the progenitors of the BLIS-producing oral probiotics, are members of the human oral cavity commensal species Streptococcus salivarius. More recently however, a number of other streptococcal and some non-streptococcal candidate oral probiotics have also been promoted. What is becoming increasingly apparent is that the future for oral probiotic applications will probably extend well beyond the attempted limitation of the direct pathological consequences of oral microbiome dysbiosis to also encompass a plethora of systemic diseases and disorders of the human host. The background to and the evolving prospects for the beneficial modulation of the oral microbiome via the application of BLIS-producing S. salivarius probiotics comprises the principal focus of the present review.

Abstract Streptococcus salivarius, the most predominant human oral microbiota, is rarely associated with neonatal sepsis. This report aims to describe a rare culture‐proven case of early‐onset sepsis in a 3‐day‐old boy with isolated high‐grade fever. Streptococcus salivarius was isolated in two consecutive hemocultures and unexpectedly resistant to the conventional empirical antibiotics.

Anatomical and physiological considerations indicate that the oral cavity is a primary source of the lung microbiota community, and recent studies have shown that the microbiota in the lungs contributes to immunological homeostasis, potentially altering the organ's susceptibility to viral infection, including SARS-CoV-2. It has been proposed that, in the case of viral infection, lung Gram-negative bacteria could promote the cytokine cascade with a better performance than a microbiota mainly constituted by Gram-positive bacteria. Recent observations also suggest that Prevotella-rich oral microbiotas would dominate the oral cavity of SARS-CoV-2-infected patients. In comparison, Streptococcus-rich microbiotas would dominate the oral cavity of healthy people. To verify if the modulation of the oral microbiota could have an impact on the current coronavirus disease, we administered for 14 days a well-recognized and oral-colonizing probiotic (S. salivarius K12) to hospitalized COVID-19 patients. The preliminary results of our randomized and controlled trial seem to prove the potential role of this oral strain in improving the course of the main markers of pathology, as well as its ability to apparently reduce the death rate from COVID-19. Although in a preliminary and only circumstantial way, our results seem to confirm the hypothesis of a direct involvement of the oral microbiota in the construction of a lung microbiota whose taxonomic structure could modulate the inflammatory processes generated at the pulmonary and systemic level by a viral infection. [ABSTRACT FROM AUTHOR]

Background: In recent years, fluoride concentrations in toothpaste for children and adults have increased. However, the effects of different concentrations on bacterial activity have rarely been compared. We aimed to investigate and compare the antibacterial activity of children's and adults' toothpaste containing 500, 1000‒1100, and 1450‒1500 ppm fluoride., Methods: Three strains of bacteria ( Streptococcus mutans , Streptococcus salivarius , and Lactobacillus casei ) were cultured in brain heart infusion agar. Thirty commercially available toothpaste products for children and adults containing 500, 1000‒1100, and 1450‒1500 ppm fluoride were selected and tested. Toothpaste's ability to inhibit bacterial growth was evaluated by agar diffusion assay, in which plates were incubated for 24 hours, and then the diameter of the microbial inhibition zone was measured. Comparisons between children's and adults' fluoride toothpastes were made using the Mann-Whitney U test. The association between bacterial growth inhibition and sodium lauryl sulfate (SLS) was analyzed by the chi-square test. A P value of <0.05 was considered statistically significant., Results: No difference in the inhibition zone was observed for different fluoride concentrations. However, there were significant differences between toothpastes for children and adults, with higher inhibition zones for adults' toothpastes. Most toothpastes for adults contained SLS, which was associated with antibacterial activity., Conclusion: Fluoride concentrations ranging from 500 to 1500 ppm did not affect bacterial growth. The antibacterial activity of toothpastes for adults was significantly higher than that of toothpastes for children, which was mainly attributed to the SLS usually added to adult formulations., Competing Interests: Authors have no conflicts of interest to declare., (©2024 The Author(s).)

Statement of the Problem: Streptococcus mutans, Streptococcus sanguinis, and Streptococcus salivarius are most common etiologic bacteria for dental caries. Different sizes of gold nanoparticles may have different antibacterial effects on these species. Purpose: This study aimed to compare the antibacterial effect of chlorhexidine and three sizes of gold nano particles (25, 60, 90nm) against clinical and standard strains of Streptococcus mutans, Streptococcus sanguinis, and Streptococcus salivarius. Materials and Method: In this cross-sectional study, the specimens were collected from 75 children aged 3-5 years old. Antibacterial effect of chlorhexidine and three sizes of gold nano particles (25, 60, 90nm) were investigated by evaluating the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against three bacterial strains. Results: The MIC and MBC of gold nanoparticles with different sizes against Streptococcus mutans, Streptococcus sanguinis, and Streptococcus salivarius were statistically different. The MIC and MBC of smaller gold nano particles (25nm) were significantly lower (p

The gut microbiome is a vast reservoir of microbes, some of which produce antimicrobial peptides called bacteriocins that may inhibit specific bacteria associated with disease. Fusobacterium nucleatum is an emerging human bacterial pathogen associated with gastrointestinal diseases including colorectal cancer (CRC). In this study, fecal samples of healthy donors were screened for potential bacteriocin-producing probiotics with antimicrobial activity against F. nucleatum. A novel isolate, designated as Streptococcus salivarius DPC6993 demonstrated a narrow-spectrum of antimicrobial activity against F. nucleatum in vitro. In silico analysis of the S. salivarius DPC6993 genome revealed the presence of genes involved in the production of the bacteriocins salivaricin A5 and salivaricin B. After 6 h in a colon fermentation model, there was a significant drop in the number of F. nucleatum in samples that had been simultaneously inoculated with S. salivarius DPC6993 + F. nucleatum DSM15643 compared to those inoculated with F. nucleatum DSM15643 alone (mean ± SD: 9243.3 ± 3408.4 vs 29688.9 ± 4993.9 copies/μl). Furthermore, 16S rRNA amplicon analysis revealed a significant difference in the mean relative abundances of Fusobacterium between samples inoculated with both S. salivarius DPC6993 and F. nucleatum DSM15643 (0.05%) and F. nucleatum DSM15643 only (0.32%). Diversity analysis indicated minimal impact exerted by S. salivarius DPC6993 on the surrounding microbiota. Overall, this study highlights the ability of a natural gut bacterium to target a bacterial pathogen associated with CRC. The specific targeting of CRC-associated pathogens by biotherapeutics may ultimately reduce the risk of CRC development and positively impact CRC outcomes.

Background Cerebral mycotic aneurysms represent a rare but life-threatening complication of infective endocarditis (IE), with high mortality rate when ruptured. Due to the lack of randomized controlled trials, management of infectious aneurysms complicating endocarditis remains a controversial topic. Case summary We describe a case of Streptococcus salivarius bicuspid aortic and mitral valve endocarditis with concurrent spontaneous mycotic aneurysm rupture and acute subarachnoid haemorrhage (SAH). A 40-year-old man with history of intravenous drug abuse presented to our emergency department with altered mental status and dyspnoea. Echocardiography documented large vegetations on a bicuspid aortic valve and on the mitral valve, causing acute severe aortic and mitral regurgitation. Brain computed tomography imaging documented a ruptured fusiform aneurysm in a distal branch of the right middle cerebral artery causing acute SAH and acute obstructive hydrocephalus. An external ventricular drain was emergently placed and endovascular embolization of the aneurysm was achieved with deployment of six coils. Blood cultures grew S. salivarius and antibiotic therapy according to microbiological sensitivities was administered. Hospital stay was complicated by acute heart failure, ST-elevation myocardial infarction, conduction disturbances, cerebral vasospasm, recurrent mycotic aneurysm rupture, and death. Discussion Clinicians should be mindful of the rare, potentially severe complication of IE with cerebral mycotic aneurysms to enable prompt treatment. Generally, central nervous system procedures are performed prior to cardiac surgical management of IE, since cardiopulmonary bypass may exacerbate cerebral haemorrhage, ischaemic damage, and oedema in areas of blood–brain barrier disruption. A multidisciplinary collaboration is crucial for optimal patient management. [ABSTRACT FROM AUTHOR]

The qualified presumption of safety (QPS) approach was developed to provide a regularly updated generic pre-evaluation of the safety of microorganisms, intended for use in the food or feed chains, to support the work of EFSA's Scientific Panels. The QPS approach is based on an assessment of published data for each agent, with respect to its taxonomic identity, the body of relevant knowledge, safety concerns and occurrence of antimicrobial resistance. Safety concerns identified for a taxonomic unit (TU) are, where possible, confirmed at the species/strain or product level and reflected by 'qualifications'. In the period covered by this statement, no new information was found that would change the status of previously recommended QPS TUs. Of the 50 microorganisms notified to EFSA in October 2021 to March 2022 (inclusive), 41 were not evaluated: 10 filamentous fungi, 1 Enterococcus faecium, 1 Clostridium butyricum, 3 Escherichia coli and 1 Streptomyces spp. because are excluded from QPS evaluation, and 25 TUs that have already a QPS status. Nine notifications, corresponding to seven TUs were evaluated: four of these, Streptococcus salivarius, Companilactobacillus formosensis, Pseudonocardia autotrophica and Papiliotrema terrestris, being evaluated for the first time. The other three, Microbacterium foliorum, Pseudomonas fluorescens and Ensifer adhaerens were re-assessed. None of these TUs were recommended for QPS status: Ensifer adhaerens, Microbacterium foliorum, Companilactobacillus formosensis and Papiliotrema terrestris due to a limited body of knowledge, Streptococcus salivarius due to its ability to cause bacteraemia and systemic infection that results in a variety of morbidities, Pseudonocardia autotrophica due to lack of body of knowledge and uncertainty on the safety of biologically active compounds which can be produced, and Pseudomonas fluorescens due to possible safety concerns. [ABSTRACT FROM AUTHOR]

Background: Dental caries and periodontal diseases are among the most common oral diseases, and research to achieve an effective strategy to overcome these diseases is necessary. One of these strategies is to use anti-septics and disinfectants, including mouthwashes. Although chlorhexidine was the first and most common mouthwash and the gold standard of anti-plaque treatments, it bears many side effects. However, herbal mouthwashes with anti-microbial properties and fewer side effects can effectively treat many of these diseases. Objectives: This study aimed to compare the efficiency of the two herbal types of mouthwash produced in Iran. Methods: The present in vitro study was conducted to investigate the anti-bacterial effects of persica and propolis mouthwashes on three strains of oral streptococci. The Zone of Inhibition (ZOI) was measured by the Disk Diffusion Method (DDM). The Minimum Inhibitory Concentration (MIC) value of each mouthwash was determined for all microorganisms using the macrodilution method. Results: Statistical analysis of data of DDM showed that the anti-bacterial effect of persica was significantly higher than propolis against Streptococcus. salivarius and Streptococcus. mutans (P

Background and purpose: Dental plaque is a biofilm that is formed on the surface of the tooth. Carious lesions are caused by inappropriate ecological changes in microbial flora of the plaque biofilm. In this study, the effect of Lactobacillus casei bacteriocin, isolated from dairy products, was investigated on Streptococcus salivarius biofilm formation. Materials and methods: In this experimental study, MRS Broth and MRS Agar medium were used to isolate three strains of Lactobacillus casei probiotic from milk samples under microaerophilic conditions. The initial identification of Lactobacillus casei was performed by sugar fermentation and other biochemical tests. Then, 16SrRNA encoding gene was confirmed by PCR and sequenced. At last, Bacteriocin was isolated by ammonium sulfate sedimentation and its molecular weight was measured by SDS-PAGE and the antimicrobial activities were investigated. The Streptococcus salivarius were isolated from dental plaque and phenotypically and biotypically identified. Molecular confirmation of the isolates was performed using gtfK specific gene by PCR. The ability to form Streptococcus salivarius biofilm and the effect of bacteriocin on biofilm formation were measured by microtiter plate. Results: After partial purification of Lactobacillus casei probiotic from dairy products, two LC3 and LC1 protein samples formed bands (35-40 kDa and about 75 kDa, respectively). The supernatant fluid from the cultivation of Lactobacillus casei and bacteriocins showed antibacterial effects against Streptococcus salivarius isolates from dental plaque and the formation of biofilm by this bacterium. Conclusion: According to this study, bacteriocin and supernatant fluid from Lactobacillus casei cultures could inhibit the growth of Streptococcus salivarius and also reduced biofilm formation, so, it could be used in oral care products.

Abstract Background Periodontal disease represents a major health concern. The administration of beneficial microbes has been increasing in popularity over efforts to manipulate the microbes using antimicrobial agents. This study determined the ability of Streptococcus salivarius to inhibit IL-6 and IL-8 production by gingival fibroblasts when activated by periodontal pathogens and their effect on the salivary microbiome. Methods Primary human gingival fibroblasts were challenged with Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Fusobacterium nucleatum and a combination of all three. IL-6 and IL-8 cytokine release were measured. Using this same model, S. salivarius K12, M18 and different supernatant and whole-cell lysate fractions of S. salivarius K12 were administered to pathogen-induced fibroblasts. A patient study of healthy participants was also conducted to determine the effect S. salivarius K12 had on the native microbiome using 16S next generation sequence analysis. Results All pathogens tested induced a significant IL-6 and IL-8 response. S. salivarius K12 or M18, did not exhibit an increase in inflammatory cytokines. When either of the probiotic strains were co-administered with a pathogen, there were significant reductions in both IL-6 and IL-8 release. This effect was also observed when gingival fibroblasts were pre-treated with either S. salivarius K12 or M18 and then stimulated with the oral pathogens. Chewing gum containing S. salivarius K12 did not alter the salivary microbiome and did not increase inflammatory markers in the oral cavity. Conclusion S. salivarius K12 and M18 prevented immune activation induced by periodontal disease pathogens. S. salivarius K12 did not alter the salivary microbiome or induce immune activation when administered as a chewing gum. These results warrant further study to determine if it may be an effective treatment in a model of periodontal disease.

Background: Oral candidiasis is a frequent form of candidiasis, caused by Candida species, in particular, Candida albicans (C. albicans). The transition of C. albicans from yeast to hyphae allows its attachment to epithelial cells, followed by biofilm formation, invasion, and tissue damage. Hence, we investigated the effect of Streptococcus salivarius subspecies thermophilus (S thermophilus) on the growth as well as biofilm and germ-tube formation of C. albicans both in vitro and in vivo in a murine model.Methods: This experimental study was performed in the Department of Medical Mycology and Parasitology, School of Medicine, in collaboration with the Central Research Laboratory and the Comparative Biomedical Center, Shiraz University of Medical Sciences, Shiraz, Iran (2017 to 2018). The inhibitory activity of S. thermophilus against Candida species growth was evaluated using the broth microdilution method, and the inhibition of C. albicans biofilm formation was measured using the XTT assay. The inhibition of C. albicans germ-tube formation by S. thermophilus was evaluated using the plate assay and fluorescence microscopy. The experimental activity of the probiotic bacterium was assessed by culture and histopathological methods in six groups of five mice, comprising those treated with four concentrations of probiotics, fluconazole, and distilled water. The one-way analysis of variance, followed by a Tukey post hoc test, was used and a P value of less than 0.05 was considered significant.Results: S. thermophilus inhibited Candida species growth at concentrations of 16 to 512 µg/mL. This probiotic inhibited the formation of C. albicans biofilms and germ tubes in a dose-dependent manner. S. thermophilus significantly reduced the colony-forming units in the mice receiving 30 mg/mL of this probiotic treatment compared with the control group (P=0.024). The histopathological analysis showed that Candida colonization was diminished in the mice following the administration of the probiotic. Conclusion: Given the inhibitory activity of S. thermophilus against the growth, transition, and biofilm formation of C. albicans, it could be used in the management of oral candidiasis.

The identification of biological fluids at crime scenes contributes to crime scene reconstruction and provides investigative leads. Traditional methods for body fluid identification are limited in terms of sensitivity and are mostly presumptive. Emerging methods based on mRNA and DNA methylation require high quality template source. An exploitable characteristic of body fluids is their distinct microbial profiles allowing for the discrimination of body fluids based on microbiome content. Microbial DNA is highly abundant within the body, robust and stable and can persist in the environment long after human DNA has degraded. 16S rRNA sequencing is the gold standard for microbial analysis; however, NGS is costly, and requires intricate workflows and interpretation. Also, species level resolution is not always achievable. Based on the current challenges, the first objective of this study was to develop a multiplex conventional PCR assay to identify vaginal fluid and saliva by targeting species-specific 16S rRNA microbial markers. The second objective was to employ droplet digital PCR (ddPCR) as a novel approach to quantify bacterial species alone and in a mixture of body fluids. Lactobacillus crispatus and Streptococcus salivarius were selected because of high abundance within vaginal fluid and saliva respectively. While Fusobacterium nucleatum and Gardnerella vaginalis , though present in healthy humans, are also frequently found in oral and vaginal infections, respectively. The multiplex PCR assay detected L. crispatus and G. vaginalis in vaginal fluid while F. nucleatum and S. salivarius was detected in saliva. Multiplex PCR detected F. nucleatum , S. salivarius and L. crispatus in mixed body fluid samples while, G. vaginalis was undetected in mixtures containing vaginal fluid. For samples exposed at room temperature for 65 days, L. crispatus and G. vaginalis were detected in vaginal swabs while only S. salivarius was detected in saliva swabs. The limit of detection was 0.06 copies/µl for F. nucleatum (2.5 ×10−9 ng/µl) and S. salivarius (2.5 ×10−6 ng/µl). L. crispatus and G. vaginalis had detection limits of 0.16 copies/µl (2.5 ×10−4 ng/µl) and 0.48 copies/µl (2.5 ×10−7 ng/µl). All 4 bacterial species were detected in mixtures and aged samples by ddPCR. No significant differences were observed in quantity of bacterial markers in saliva and vaginal fluid. The present research reports for the first time the combination of the above four bacterial markers for the detection of saliva and vaginal fluid and highlights the sensitivity of ddPCR for bacterial quantification in pure and mixed body fluids. • 16S rRNA gene markers specific to bacterial species found in body fluids can be targeted for body fluid identification. • F. nucleatum , S. salivarius , L. crispatus and G. vaginalis markers were multiplexed for saliva and vaginal fluid detection. • Droplet digital PCR was sensitive for quantification of saliva and vaginal fluid specific bacteria in mixed and aged samples. [ABSTRACT FROM AUTHOR]

Body fluid detection is an important component in the toolbox of forensic scientists, with saliva playing a particularly critical role in forensic evidence. Given that each body fluid possesses a distinct microbiome, the identification of body fluid based on specific representatives of the microbiota presents an appealing approach for forensic applications. In this study, we have developed a real-time polymerase chain reaction (RT-PCR)-based method for the precise identification of saliva, focusing on three bacteria highly associated with saliva but not with other tested body fluids - Porphyromonas gingivalis , Fusobacterium nucleatum , and Streptococcus salivarius. The inclusion of these three bacterial species enhances the accuracy of detection and reinforces validation. Notably, specific identification of saliva was achievable even at low concentrations where Phadebas, a commonly used method for saliva detection, proved ineffective. Importantly, bacteria-based saliva detection utilizes DNA generated for small tandem repeats (STR) profiling, facilitating seamless integration into forensic laboratories and optimizing DNA sample utilization. This study collectively proposes an effective bacterial DNA-based approach for saliva identification, demonstrating promising potential for forensic applications. • Oral bacterial DNA serves as a specific identifier for saliva, distinguishing it from other body fluids. • Bacterial DNA-based saliva identification proves more sensitive than the conventional Phadebas method. • Forensic exhibit DNA extraction facilitates both saliva identification and STR profiling. • RT-PCR is employed for the execution of both saliva identification and STR profiling. [ABSTRACT FROM AUTHOR]

Statement of the Problem: There are global efforts for introducing a new herbal antimicrobial agent with minimal side effects. There are some reports about the antimicrobial properties of Pimpinella anisum and Oregano Vulgare. Purpose: In this study, the antimicrobial properties of Pimpinella anisum and Oregano Vulgare have been assessed. Material and Method: In this experimental in vitro study, the dental plaque samples were collected from children aged 3 to 5 years old who were referred to a private dental office with diagnosis of dental caries. After determination of the bacterial colonies of Streptococcus sanguinis, Streptococcus mutans and Streptococcus salivarius, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ethanolic and methanolic extracts of Pimpinella anisum and Oregano vulgare were measured by macrodilution and microdilution methods. Results: The mean MIC and MBC of Pimpinella anisum extract and Oregano vulgare extract and their combination against Streptococcus mutans, Streptococcus sanguinis, and Streptococcus salivarius were statistically different (p< 0.001). The combination of these extracts showed the lowest MIC and MBC. Conclusion: Hydroalcoholic extracts of the Pimpinella anisum and Oregano Vulgare were effective antibacterial agent against Streptococcus mutans, Streptococcus salivarius, and Streptococcus sanguinis so the combination of these two extracts showed the highest antibacterial properties on all the bacteria evaluated. [ABSTRACT FROM AUTHOR]

Streptococcus salivarius, the most predominant human oral microbiota, is rarely associated with neonatal sepsis. This report aims to describe a rare culture‐proven case of early‐onset sepsis in a 3‐day‐old boy with isolated high‐grade fever. Streptococcus salivarius was isolated in two consecutive hemocultures and unexpectedly resistant to the conventional empirical antibiotics. [ABSTRACT FROM AUTHOR]

Abstract Background In oral candidiasis models, Candida albicans and Streptococcus salivarius sp. biofilms have an antagonistic relationship. Due to this, S. salivarius have been used experimentally as probiotic. However, the interaction between these microorganisms in the peri-implantitis-like microenvironment remains unknown. This study aimed to evaluate the interaction between C. albicans and S. salivarius biofilms developed on titanium surfaces, under reduced oxygen levels. Methods Titanium specimens were pre-conditioned with artificial saliva (1 h, 37 °C). Single-species biofilms of C. albicans (ATCC 90028) and co-culture biofilms of C. albicans and S. salivarius (ATCC 7073) was developed for 24 and 72 h on titanium specimens. Subsequently, the effect of these intervals of biofilm formation and the interactions among the cells were evaluated. Biofilms from cultures were collected and analyzed for cell viability (CFU/mL), biofilm biomass, and total protein dosage. Data were analyzed using Mann–Whitney test (α = 5%). In addition, co-culture biofilms were analyzed using fluorescence microscopy. Results C. albicans growth did not change due to the presence of S. salivarius. Besides, co-culture biofilms showed a significant difference in the number of viable cells between 24 and 72 h of biofilm development (p

Background: Microbial plaque-induced oral diseases are among the most common diseases worldwide. The present study aimed to compare the antimicrobial effect of electrolyzed water (EW), (acidic, mildly basic, and basic) on the growth of bacterial species producing dental plaque and to assess their cytotoxicity on fibroblasts and epithelial cells.Methods: The study was performed at Shahid Beheshti University of Medical Sciences in 2019. Several bacterial species (Streptococcus salivarius, Staphylococcus aureus, Lactobacillus casei, and Aggregatibacter actinomycetemcomitans) were treated with different EW types at three pH values (3, 9, and 11) for 30 seconds and subsequently, the colonies were counted. The cytotoxic effect of these EW types was evaluated on HeLa and L929 cell lines at 30 seconds, 1 minute, and 5 minutes. GraphPad Prism 6.0 was used for statistical analysis. The Kruskal-Wallis test followed by Mann-Whitney U and one-way analysis of variance followed by Tukey’s test were used to analyze bacterial activity and cell cytotoxicity, respectively. PResults: EW types significantly inhibited bacterial growth at all pH values. The strongest antibacterial activity of EW was against A. actinomycetemcomitans (PConclusion: The contradictory effects of the EW types on both HeLa and fibroblasts, in addition to variable results at different exposure times, indicated that the effect of EW could vary depending on cell types and treatment periods.

Abstract Aim The aim was to investigate the salivary detection frequencies and quantities of caries‐associated bacteria from patients with orthodontic brackets. Methods Patients wearing orthodontic brackets (n = 40, mean age = 26 years) and healthy controls without brackets (n = 40, mean age = 17 years) were enrolled in the study. Saliva samples from each patient was collected. After DNA purification, target species comprising streptococci and a Lactobacillus species were detected and quantified from the samples using polymerase chain reaction (PCR) and real‐time quantitative PCR. Results Detection frequencies did not differ between the orthodontic patients and the control subjects for any target species except for Streptococcus sobrinus, which showed significantly lower detection rates in orthodontic patients (p

Human breast milk Streptococcus spp. are transferred to infant guts via breast feeding, but their effects on the gut microbiota and immunity remain unclear. In this study, we characterized gut microbiota and immune modulatory properties of human breast milk S. salivarius F286 and S. parasanguinis F278 that had been shown to be able to colonize gut. The two Streptococcus strains were orally administered to mouse pups individually at 1 × 107 cells/day from postnatal Days 1 to 21. At postnatal week 3 (the weaning period), S. salivarius F286 reduced the colonic microbiota α-diversity, increased 21 amplicon sequence variants (ASVs), including bacteria from Akkermansia, Intestinimonas, and Lachnospiraceae, and decreased 52 ASVs, including bacteria from Eubacterium, Bifidobacterium, Escherichia-Shigella, and Turicibacter; however, S. parasanguinis F278 didn't change the colonic microbiota. Both Streptococcus strains reduced the ileal mRNA expression of cytokine/transcription factor representatives of T helper (Th) cells, including IFN-γ (Th1), Gata3 (Th2), and TGF-β (Treg) in 2-week-old suckling mice, and promoted the ileal expression of Foxp3 and TGF-β, which are representatives of anti-inflammatory Treg cells, in 3-week-old weaning mice. The two Streptococcus strains exhibited anti-inflammatory potential when incubated in vitro with human peripheral blood mononuclear cells and TNF-α-treated gut epithelial HT29 cells. In C. elegans, both strains activated immune response genes, which was associated with their lifespan-prolonging effects. Our results suggest that S. salivarius F286 and S. parasanguinis F278 may exert regulatory (anti-inflammatory) roles in gut immunity and S. salivarius F286 can modulate gut microbiota, and highlight the probiotic potential of milk S. salivarius and S. parasanguinis strains.

Streptococcus salivarius (S. salivarius) is an oral commensal bacterium that rarely causes disease. Here, we report a case of emphysematous cystitis due to S. salivarius infection in a patient with a neurogenic bladder. A 56-year-old woman was hospitalized and managed for left putamen hemorrhage. Afterward, she developed poor oral intake. Although the patient was afebrile, laboratory test results suggested an inflammatory response. Urinalysis revealed pyuria and hematuria. Abdominal computed tomography revealed a thickened urinary bladder wall and intraluminal gas. Additionally, she was diagnosed with a neurogenic bladder as she had approximately 200 mL of residual urine. The patient was diagnosed with emphysematous cystitis, and S. salivarius was isolated from urine culture specimens. The patient’s condition improved immediately after treatment, which included bladder drainage and administration of appropriate antibiotics. We could not find any report on S. salivarius causing urinary tract infections, such as emphysematous cystitis. Accordingly, we report this case along with a review of the literature.

Background: Various methods, including the use of probiotics, have been suggested to prevent caries. Caries, which is mainly caused by Streptococcus mutans , is one of the bacterial diseases that imposes a heavy cost on society. The present study was conducted to investigate the probiotic products available in Iranian pharmacies that are used for caries prevention., Materials and Methods: In this double-blind randomized clinical trial, 40 students of medicine and pharmacy were randomly allocated to two equal groups of intervention and control using random allocation software. The intervention group used a probiotic pill containing Streptococcus salivarius M18 and K12 bacteria every night before going to bed. The control group used a mouth freshener tablet with the same flavor as the probiotic tablet every night before going to bed. The data were analyzed by SPSS (version 24) software using descriptive statistics (central tendency and dispersion) and inferential statistics (paired t -test and independent t -test). Data were collected using Excel software, and statistical analyses were performed by SPSS software (version 24)., Results: The mean number of S. mutans in the intervention group was 754.5 cfu/mm before the intervention and 1701.5 cfu/mm after the intervention, which showed a statistically significant difference ( P < 0.05). In the control group, the mean S. mutans was 683 cfu/mm at the beginning of the intervention and 659 cfu/mm at the end of the intervention, which did not indicate a statistically significant difference ( P > 0.05). Moreover, the normality of data was checked by the Kolmogorov-Smirnov test., Conclusion: The mean number of S. mutans bacteria in the group using probiotic tablets was significantly increased compared to those of the control group. However, further studies are suggested to evaluate these products., Competing Interests: The authors of this manuscript declare that they have no conflicts of interest, real or perceived, financial or non-financial in this article., (Copyright: © 2024 Dental Research Journal.)

We herein report a 67-year-old Japanese woman with liver cirrhosis caused by primary biliary cholangitis. The patient was admitted to the hospital with loss of consciousness. Hepatic encephalopathy (HE) was diagnosed after diagnostic imaging and symptom assessments. Molecular biology tests were performed on oral saliva and stool samples. The test results indicated sequence similarity between urease-positive S. salivarius in both oral saliva and stool, as revealed by the signals in the overlapping peaks. This bacterium can potentially increase ammonia production in the gut, leading to HE in patients with liver cirrhosis.

Background. Dental caries is known as a multimicrobial disease. Caries are very prevalent in numerous countries, and the incidence is higher in underdeveloped countries than in developed countries. Dental caries is a major public health problem, and it is the most prevalent health problem across the world, affecting 2.4 billion people. Natural mouthwashes can be beneficial in the prevention of dental caries and oral infections without the side effects of synthetic mouthwashes. Aim. The aim of the present study was to investigate the antibacterial, antifungal, and cytotoxicity properties of sea salt from different areas of Iran. Methods and Materials. Sea salts from different areas (Urmia, Qom, and Jarquyeh) of Iran were collected. In order to define the elemental and mineralogical features of different salt samples, X-ray powder diffraction (XRD) was employed. Different concentrations (0.19–50 mg/mL) of sea salt were used in the antimicrobial and antibiofilm tests. The antimicrobial (MIC, MBC, MFC, and DAD tests) and antibiofilm (formation and degradation tests) effects were evaluated against L. acidophilus, S. aureus, E. coli, S. mitis, S. mutans, S. salivarius, and C. albicans. The cytotoxic effect of salts was evaluated on human gingival fibroblasts by the MTT test. Results. The range of MIC values in mg ml−1 was as follows: S. salivarius (50), S. mutans (50), S. mitis (50), L. acidophilus (12.5 to >50), C. albicans (50), E. coli (12.5 to 25), and S. aureus (12.5 to 25), while MBC values were, S. mutans (>50), S. salivarius (>50), S. mitis (>50), L. acidophilus (50 to >50), C. albicans (>50), E. coli (50), and S. aureus (50). MTT results showed that more than 50% of cell viability depends on decreasing the salt concentration (<1.56 mg/ml). Conclusion. Sea salts had significant antimicrobial effects on cariogenic bacteria and C. albicans. Therefore, sea salts can be a suitable candidate for mouthwash. [ABSTRACT FROM AUTHOR]

Statement of the Problem: Streptococcus mutans, Streptococcus sanguinis, and Streptococcus salivarius are most common etiologic bacteria for dental caries. Different sizes of gold nanoparticles may have different antibacterial effects on these species. Purpose: This study aimed to compare the antibacterial effect of chlorhexidine and three sizes of gold nano particles (25, 60, 90nm) against clinical and standard strains of Streptococcus mutans, Streptococcus sanguinis, and Streptococcus salivarius. Materials and Method: In this cross-sectional study, the specimens were collected from 75 children aged 3-5 years old. Antibacterial effect of chlorhexidine and three sizes of gold nano particles (25, 60, 90nm) were investigated by evaluating the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against three bacterial strains. Results: The MIC and MBC of gold nanoparticles with different sizes against Streptococcus mutans, Streptococcus sanguinis, and Streptococcus salivarius were statistically different. The MIC and MBC of smaller gold nano particles (25nm) were significantly lower (p<0.001) than larger ones. Patient-derived bacteria had significantly higher values of MIC and MBC in comparison to standard species (p<0.001). Conclusion: The results of this study confirmed the significant size-dependency of gold nano particles for antibacterial activity. As the size of gold nano particles decrease, the antibacterial properties enhance. [ABSTRACT FROM AUTHOR]