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1.
J Med Microbiol ; 72(2)2023 Feb.
Article in English | MEDLINE | ID: mdl-36762526

ABSTRACT

Introduction. Mucormycosis is a severe angio-invasive fungal infection caused by mucormycetes, a group of fungi that are ubiquitous in the environment. The incidence of mucormycosis has been surging rapidly due to the global corona virus disease 2019 (COVID-19) pandemic.Gap Statement. The complete picture of the causative fungi associated with mucormycosis and their phylogenetic relationships are not well defined.Aim. This meta-analysis aimed to collate all confirmed fungal pathogens that cause mucormycosis, and assess their taxonomic relationships.Methodology. All types of articles in the PubMed database that report fungi as a cause of mucormycosis were reviewed. We summarized the fungal morphological characteristic up to the genus level. The internal transcribed spacer (ITS) nucleotide sequences of these fungi were retrieved from the National Center for Biotechnology Information (NCBI) and UNITE databases whenever available, and multiple sequence analysis was conducted using Clustal W. The phylogenetic tree was constructed using mega version 7.Results. Forty-seven fungal species were identified as pathogens causing mucormycosis in humans. Thirty-two fungal species were phylogenetically grouped into three clades, and it was evident that the ITS sequences have well-conserved regions in all clades, especially from the 400th to 500th base pairs.Conclusion. The findings of this work contribute to the descriptive data for fungi that cause mucormycosis, emphasizing the need for robust phylogenetic approaches when identifying clinical isolates from infected patients.


Subject(s)
COVID-19 , Mucormycosis , Humans , Phylogeny , Fungi , DNA, Ribosomal Spacer/genetics , DNA, Fungal/genetics , DNA, Fungal/analysis
2.
Biofouling ; 38(6): 614-627, 2022 07.
Article in English | MEDLINE | ID: mdl-35899682

ABSTRACT

This study aimed to determine the effect of synbiotic Musa acuminata skin extract (MASE) and Streptococcus salivarius K12 (K12) on Candida species biofilm formation. Liquid chromatography quadrupole time-of-flight (LC-Q-TOF-MS) was conducted to characterize MASE. To determine the effect of synbiotic on Candida biofilm, 200 µL of RPMI-1640 containing Candida, K12, and MASE were pipetted into the same well and incubated at 37 °C for 72 h. A similar protocol was repeated with K12 or MASE to determine the probiotic and prebiotic effects, respectively. Dimorphism, biofilm biomass, and Candida total cell count (TCC) were determined. A total of 60 compounds were detected in MASE. C. albicans (ALT5) and Candida lusitaniae exhibited the highest reduction in biofilm biomass when co-cultured with prebiotic (77.70 ± 7.67%) and synbiotic (97.73 ± 0.28%), respectively. All Candida spp. had decreased TCC and hyphae when co-cultured with synbiotic. In conclusion, MASE and K12 inhibit Candida biofilm formation.


Subject(s)
Musa , Streptococcus salivarius , Synbiotics , Biofilms , Candida , Candida albicans , Plant Extracts/pharmacology
3.
J Med Microbiol ; 71(6)2022 Jun.
Article in English | MEDLINE | ID: mdl-35687657

ABSTRACT

Candida auris is a recently emerged multidrug-resistant fungal pathogen that causes life-threatening infections to the human population worldwide. Recent rampant outbreaks of C. auris in coronavirus disease 2019 (COVID-19) patients, together with outbreaks in over 45 countries, highlight its threat to patients and healthcare economies. Unlike other pathogenic Candida species, C. auris is capable of surviving in abiotic surfaces of healthcare facilities for prolonged periods, leading to increased risk of transmission within nosocomial settings. C. auris is resistant to multiple classes of antifungal agents, forms dry biofilms and transmits independently to regional epicentres, making its eradication from nosocomial environment arduous. The lack of strategies for environmental decontamination of C. auris from nosocomial settings is evident from the generic guidance and recommendations provided by leading global healthcare bodies. Therefore, this minireview discusses the current guidelines for environmental decontamination of C. auris and compounds and strategies currently under investigation for potential future use. While established guidelines recommend the use of products mainly consisting of sodium hypochlorite and hydrogen peroxide, initial works have been reported on the promising anti-C. auris properties of various other compounds and some biocompatible alternatives. Further validation of these approaches, coupled up with environmentally friendly decontamination protocols, are warranted to achieve superior elimination of C. auris from healthcare settings.


Subject(s)
COVID-19 , Cross Infection , Antifungal Agents/pharmacology , COVID-19/prevention & control , Candida , Candida auris , Cross Infection/prevention & control , Decontamination , Humans
4.
HardwareX ; 11: e00279, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35509923

ABSTRACT

In this work we have designed and developed a low cost and simple instrument to purify air in an enclosure. The device sucks up the air in the enclosed area, kills the microorganisms and let clean air flow out. A combination of an ultra violet light and an electric field are used to kill the microorganisms in air. Three electric field chambers (radial, parallel, perpendicular) are used to clean air more effectively. Stainless steel meshes were used to increase the density of the electric fields. The outer covers were made with plastic and wood. The instrument was tested against an evaporated bacterial solution (Staphylococcus aureus) by letting it flow through the instrument and measuring the bacterial concentration of the output air. The results showed the instrument is extremely effective even when tested against high bacterial concentrations. The instrument is extremely useful to clean air in closed rooms such as in hospitals, schools, etc. and prevent the spread of airborne diseases.

5.
Int Dent J ; 72(5): 607-620, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35367044

ABSTRACT

OBJECTIVES: Studies reviewing orofacial mycoses in coronavirus disease-2019 (COVID-19) caused by severe acute respiratory syndrome 2 (SARS-CoV-2) infection are sparse. Here we review the major oral and maxillofacial mycoses of COVID-19, the associated comorbidities, and the probable precipitating factors. METHODS: English-language manuscripts published between March 2020 and October 2021 were searched using PubMed, OVID, SCOPUS, and Web of Science databases, using appropriate keywords. RESULTS: We identified 30 articles across 14 countries, which met the inclusion criteria of PRISMA guidelines. These yielded a total of 292 patients with laboratory-confirmed COVID-19, 51.4% (n = 150) of whom presented with oral and maxillofacial fungal infections, mainly comprising candidosis, mucormycosis, and aspergillosis. Candida infections were the most prevalent, present in 64% (n = 96), followed by mucormycosis, and only a single case of aspergillosis was noted. Oral and maxillofacial mycoses were predominantly seen in those with comorbidities, especially in those with diabetes (52.4%). Oral mucormycosis was noted in 8.6% (n = 13) and mainly manifested on the hard palate. An overall event rate of oral/maxillofacial mucormycosis manifestation in patients with COVID-19 with diabetes mellitus type 1/2 was about 94% (49/52; 95% confidence interval, 0.73%-0.89%), implying a very high association between diabetes mellitus and the latter condition. All fungal infections appeared either concurrently with COVID-19 symptoms or during the immediate recovery period. CONCLUSIONS: SARS-CoV-2 infection-related immunosuppression, steroid therapy, as well as comorbidities such as diabetic hyperglycemia appear to be the major predisposing factors for the onset of oral and maxillofacial mycoses in patients with COVID-19 across all age groups.


Subject(s)
COVID-19 , Mycoses , COVID-19/complications , Comorbidity , Humans , Mycoses/diagnosis , SARS-CoV-2 , Steroids
8.
Dent Mater ; 38(1): 147-157, 2022 01.
Article in English | MEDLINE | ID: mdl-34836699

ABSTRACT

OBJECTIVE: To develop an aesthetic resin composite using a nitrogen-doped titanium dioxide (NTiO2) filler that possesses antimicrobial properties against cariogenic bacteria. METHODS: N-TiO2 powder was manufactured by calcining commercial TiO2 with urea. Free radical release from the N-TiO2 powder under visible light irradiation was analysed using UV-Vis spectrophotometry. The N-TiO2 powder was incorporated into a dental resin and the photocatalytic activity assessed using a dye under both visible light and dark conditions. Using XTT assay to measure the cellular metabolic activity, the antibacterial properties of the N-TiO2 /resin composite discs were tested using Streptococcus mutans. RESULTS: Doping nitrogen of TiO2 resulted in a band gap shift towards the visible light spectrum, which enabled the powder to release reactive oxygen species when exposed to visible light. When incorporated into a dental resin, the N-TiO2/resin composite still demonstrated sustained release of reactive oxygen species, maintaining its photocatalytic activity and showing an antibacterial effect towards Streptococcus mutans under visible light conditions. SIGNIFICANCE: N-TiO2 filled resin composite shows great promise as a potential aesthetic resin based adhesive for orthodontic bonding.


Subject(s)
Anti-Infective Agents , Nitrogen , Anti-Bacterial Agents/pharmacology , Esthetics, Dental , Light , Polymers , Titanium/pharmacology
9.
Sci Rep ; 10(1): 7769, 2020 05 08.
Article in English | MEDLINE | ID: mdl-32385378

ABSTRACT

Microorganisms employ quorum sensing (QS) mechanisms to communicate with each other within microbial ecosystems. Emerging evidence suggests that intraspecies and interspecies QS plays an important role in antimicrobial resistance in microbial communities. However, the relationship between interkingdom QS and antimicrobial resistance is largely unknown. Here, we demonstrate that interkingdom QS interactions between a bacterium, Pseudomonas aeruginosa and a yeast, Candida albicans, induce the resistance of the latter to a widely used antifungal fluconazole. Phenotypic, transcriptomic, and proteomic analyses reveal that P. aeruginosa's main QS molecule, N-(3-Oxododecanoyl)-L-homoserine lactone, induces candidal resistance to fluconazole by reversing the antifungal's effect on the ergosterol biosynthesis pathway. Accessory resistance mechanisms including upregulation of C. albicans drug-efflux, regulation of oxidative stress response, and maintenance of cell membrane integrity, further confirm this phenomenon. These findings demonstrate that P. aeruginosa QS molecules may confer protection to neighboring yeasts against azoles, in turn strengthening their co-existence in hostile polymicrobial infection sites.


Subject(s)
Antifungal Agents/pharmacology , Candida albicans/drug effects , Candida albicans/physiology , Drug Resistance, Fungal , Fluconazole/pharmacology , Pseudomonas aeruginosa/physiology , Quorum Sensing , Biosynthetic Pathways , Ergosterol/biosynthesis , Gene Expression Regulation, Fungal/drug effects , Microbial Interactions
10.
Appl Bionics Biomech ; 2020: 9160528, 2020.
Article in English | MEDLINE | ID: mdl-32399060

ABSTRACT

Elderly and disabled population is rapidly increasing. It is important to uplift their living standards by improving the confidence towards daily activities. Navigation is an important task, most elderly and disabled people need assistance with. Replacing human assistance with an intelligent system which is capable of assisting human navigation via wheelchair systems is an effective solution. Hand gestures are often used in navigation systems. However, those systems do not possess the capability to accurately identify gesture variances. Therefore, this paper proposes a method to create an intelligent gesture classification system with a gesture model which was built based on human studies for every essential motion in domestic navigation with hand gesture variance compensation capability. Experiments have been carried out to evaluate user remembering and recalling capability and adaptability towards the gesture model. Dynamic Gesture Identification Module (DGIM), Static Gesture Identification Module (SGIM), and Gesture Clarifier (GC) have been introduced in order to identify gesture commands. The proposed system was analyzed for system accuracy and precision using results of the experiments conducted with human users. Accuracy of the intelligent system was determined with the use of confusion matrix. Further, those results were analyzed using Cohen's kappa analysis in which overall accuracy, misclassification rate, precision, and Cohen's kappa values were calculated.

11.
Int J Pharm ; 578: 119096, 2020 Mar 30.
Article in English | MEDLINE | ID: mdl-32006626

ABSTRACT

In contrast to the plethora of antibacterial agents, only a handful of antifungals are currently available to treat Candida albicans biofilm-associated infections. Additional novel antibiofilm strategies to eliminate C. albicans biofilm infections are needed. This study aims to improve the efficacy of a widely used azole, fluconazole by co-delivering it with a Pseudomonas aeruginosa quorum sensing molecule (QSM), N-3-oxo-dodecanoyl-L-homoserine lactone (C12AHL) in a liposomal formulation. C12AHL is known to inhibit C. albicans' morphological transition and biofilm formation. Four different formulations of liposomes with fluconazole (L-F), with C12AHL (L-H), with fluconazole and C12AHL (L-HF), and a drug-free control (L-C) were prepared using a thin-film hydration followed by extrusion method, and characterised. The effect of liposomes on colonising (90 min-24 h) and preformed (24 h) C. albicans biofilms were assessed using a standard biofilm assay. Biofilm viability (XTT reduction assay), biomass (Safranin-O staining) and architecture (confocal laser scanning microscopy, CLSM) were determined. Similar efficiencies of fluconazole entrapment were noticed in L-HF and L-F (11.74% vs 10.2%), however, L-HF released greater quantities of fluconazole compared to L-F during 24 h (4.27% vs 0.97%, P < 0.05). The entrapment and release of C12AHL was similar for L-H and L-HF liposomes (33.3% vs 33% and 88.9% vs 92.3% respectively). L-HF treated colonising, and preformed biofilms exhibited >80%, and 60% reduction in their respective viabilities at a fluconazole concentration as low as 5.5 µg/mL compared to 12% and 36%, respective reductions observed in L-F treated biofilms (P < 0.05). CLSM confirmed biofilm disruption, lack of hyphae, and reduction in biomass when treated with L-HF compared to other liposomal preparations. Liposomal co-delivery of C12AHL and fluconazole appears to suppress C. albicans biofilms through efficacious disruption of the biofilm, killing of constituent yeasts, and diminishing their virulence at a significantly lower antifungal dose. Therefore, liposomal co-formulation of C12AHL and fluconazole appears to be a promising approach to improve the efficacy of this common triazole against biofilm-mediated candidal infections.


Subject(s)
4-Butyrolactone/analogs & derivatives , Antifungal Agents/administration & dosage , Candida albicans/drug effects , Drug Delivery Systems , Fluconazole/administration & dosage , Homoserine/analogs & derivatives , Pseudomonas aeruginosa/physiology , Quorum Sensing , 4-Butyrolactone/administration & dosage , 4-Butyrolactone/chemistry , Antifungal Agents/chemistry , Biofilms/drug effects , Candida albicans/physiology , Drug Liberation , Fluconazole/chemistry , Homoserine/administration & dosage , Homoserine/chemistry , Liposomes
12.
JDR Clin Trans Res ; 5(2): 118-126, 2020 04.
Article in English | MEDLINE | ID: mdl-31283892

ABSTRACT

INTRODUCTION: Ecological approaches to dental caries prevention play a key role in attaining long-term control over the disease and maintaining a symbiotic oral microbiome. OBJECTIVES: This study aimed to investigate the microbial ecological effects of 2 interventional dentifrices: a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) dentifrice and the same dentifrice supplemented with a polyphenol-rich cranberry extract. METHODS: The interventional toothpastes were compared with each other and with an active control fluoride dentifrice in a double-blinded randomized controlled trial. Real-time quantitative polymerase chain reaction (qPCR) analysis was used to determine changes in the bacterial loads of 14 key bacterial species (8 caries associated and 6 health associated) in the dental plaque of trial participants after they used the dentifrices for 5 to 6 wk. RESULTS: From the baseline to the recall visit, significant differences were observed between the treatment groups in the bacterial loads of 2 caries-associated bacterial species (Streptococcus mutans [P < 0.001] and Veillonella parvula [P < 0.001]) and 3 health-associated bacterial species (Corynebacterium durum [P = 0.008], Neisseria flavescens [P = 0.005], and Streptococcus sanguinis [P < 0.001]). Compared to the fluoride control dentifrice, the CPP-ACP dentifrice demonstrated significant differences for S. mutans (P = 0.032), C. durum (P = 0.007), and S. sanguinis (P < 0.001), while combination CPP-ACP-cranberry dentifrice showed significant differences for S. mutans (P < 0.001), V. parvula (P < 0.001), N. flavescens (P = 0.003), and S. sanguinis (P < 0.001). However, no significant differences were observed in the bacterial load comparisons between the CPP-ACP and combination dentifrices for any of the targeted bacterial species (P > 0.05). CONCLUSIONS: Overall, the results indicate that dentifrices containing CPP-ACP and polyphenol-rich cranberry extracts can influence a species-level shift in the ecology of the oral microbiome, resulting in a microbial community less associated with dental caries (Australian New Zealand Clinical Trial Registry ANZCTR 12618000095268). KNOWLEDGE TRANSFER STATEMENT: The results of this randomized controlled trial indicate that dentifrices containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and polyphenol-rich cranberry extracts were able to beneficially modulate the microbial ecology of dental plaque in a group of high caries-risk patients. This could contribute toward lowering the risk of developing new caries lesions, an important goal sought by patients, clinicians, and policy makers.


Subject(s)
Dental Caries , Dental Plaque , Vaccinium macrocarpon , Australia , Caseins , Corynebacterium , Humans , Neisseria , Plant Extracts , Tooth Remineralization , Veillonella
13.
Caries Res ; 53(6): 643-649, 2019.
Article in English | MEDLINE | ID: mdl-31163430

ABSTRACT

BACKGROUND: Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) acts as a salivary biomimetic that provides bioavailable calcium and phosphate ions to augment fluoride-mediated remineralisation of early caries lesions. However, there are indications that it may also have beneficial ecological effects on the oral microbiome. OBJECTIVE: This in vitro study investigated whether CPP-ACP could influence microbial counts, acidogenicity, and the relative abundance of specific caries- and health-associated bacterial -species in polymicrobial biofilms. METHODS: Saliva-derived polymicrobial biofilms were grown for 96 h in a cariogenic environment and treated every 12 h with 2% CPP-ACP or vehicle control. Colony forming units (CFUs) and acidogenicity were estimated from the treated biofilms. Microbial ecological effects of CPP-ACP were assessed based on the relative abundance of 14 specific caries- and health-associated -bacterial species using a real-time quantitative PCR assay. -Results: CPP-ACP-treated biofilms showed relatively modest, but significant, reductions in microbial CFUs (21% reduction, p = 0.008) and acidogenicity (33% reduction, p < 0.001), compared to the control-treated biofilms. The CPP-ACP treated biofilms also exhibited significantly lower bacterial loads of cariogenic Scardovia wiggsiae (fold change 0.017, p < 0.001) and Prevotella denticola(fold change 0.005, p < 0.001), and higher bacterial loads of commensal Streptococcus sanguinis(fold change 30.22, p < 0.001), S. mitis/oralis(fold change 9.66, p = 0.012), and S. salivarius/thermophilus(fold change 89.35, p < 0.001) than the control-treated biofilms. CONCLUSIONS: The results indicate that CPP-ACP has virulence-attenuating attributes that can influence a beneficial microbial ecological change in the biofilm.


Subject(s)
Biofilms/drug effects , Calcium Phosphates/pharmacology , Caseins/pharmacology , Saliva/microbiology , Tooth Remineralization , Actinobacteria/drug effects , Bacterial Load , Humans , In Vitro Techniques , Phosphopeptides , Prevotella/drug effects , Streptococcus/drug effects , Virulence
14.
Periodontol 2000 ; 80(1): 148-176, 2019 06.
Article in English | MEDLINE | ID: mdl-31090135

ABSTRACT

For millions of years, microbiota residing within us, including those in the oral cavity, coexisted in a harmonious symbiotic fashion that provided a quintessential foundation for human health. It is now clear that disruption of such a healthy relationship leading to microbial dysbiosis causes a wide array of infections, ranging from localized, mild, superficial infections to deep, disseminated life-threatening diseases. With recent advances in research, diagnostics, and improved surveillance we are witnessing an array of emerging and re-emerging oral infections and orofacial manifestations of systemic infections. Orofacial infections may cause significant discomfort to the patients and unnecessary economic burden. Thus, the early recognition of such infections is paramount for holistic patient management, and oral clinicians have a critical role in recognizing, diagnosing, managing, and preventing either new or old orofacial infections. This paper aims to provide an update on current understanding of well-established and emerging viral, bacterial, and fungal infections manifesting in the human oral cavity.


Subject(s)
Mouth Mucosa , Mycoses , Algorithms , Causality , Humans , Incidence
15.
Arch Oral Biol ; 102: 1-6, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30951891

ABSTRACT

OBJECTIVE: To investigate the effect of cranberry extracts on saliva-derived polymicrobial biofilms with regards to biofilm biomass, acidogenicity, exopolysaccharide (EPS)/microbial biovolumes, colony forming unit (CFU) counts, and the relative abundance of specific caries- and health-associated bacteria. METHODS: Saliva-derived polymicrobial biofilms were grown for 96 h in a cariogenic environment and treated for 2 min every 12 h over the entire biofilm growth period with 500 µg/mL cranberry extract or vehicle control. The effect of the cranberry extract on biofilm behaviour was evaluated using different assays and its influence on key cariogenic and health-associated bacterial populations was assessed with a microarray real-time quantitative PCR method. RESULTS: Cranberry-treated biofilms showed significant drops in biomass (38% reduction, P < 0.001), acidogenicity (44% reduction, P < 0.001), EPS/microbial biovolume ratios (P = 0.033), and CFU counts (51% reduction, P = 0.001). Furthermore, the cranberry extracts effected a significantly lower relative abundance of caries-associated Streptococcus sobrinus (fold change 0.004, P = 0.002) and Provotella denticola (0.002, P < 0.001), and a significantly higher relative abundance of the health-associated Streptococcus sanguinis (fold change 90.715, P = 0.001). CONCLUSIONS: The cranberry extract lowered biofilm biomass, acidogenicity, EPS/microbial biovolumes, CFU counts, and modulated a beneficial microbial ecological change in saliva-derived polymicrobial biofilms.


Subject(s)
Biofilms , Dental Caries , Vaccinium macrocarpon , Humans , Plant Extracts , Polyphenols , Streptococcus mutans
16.
Eur J Oral Sci ; 127(2): 122-129, 2019 04.
Article in English | MEDLINE | ID: mdl-30592324

ABSTRACT

Dark-colored fruit berries are a rich source of polyphenols that could provide innovative bioactive molecules as natural weapons against dental caries. High-quality extracts of cranberry, blueberry, and strawberry, and a combination of the three berry extracts (Orophenol), were used to treat 24-h-old Streptococcus mutans biofilms. The grown biofilms were treated with the berry extracts at concentrations ranging from 62.5 to 500 µg ml-1 . Treated biofilms were assessed for metabolic activity, acidogenicity, biovolumes, structural organization, and bacterial viability. The biofilms treated with the cranberry and Orophenol extracts exhibited the most significant reductions in metabolic activity, acid production, and bacterial/exopolysaccharide (EPS) biovolumes, while their structural architecture appeared less compact than the control-treated biofilms. The blueberry extract produced significant reductions in metabolic activity and acidogenicity only at the highest concentration tested, without significantly affecting bacterial/EPS biovolumes or biofilm architecture. Strawberry extracts had no significant effects on S. mutans biofilms. None of the berry extracts were bactericidal for S. mutans. The results indicate that cranberry extract was the most effective extract in disrupting S. mutans virulence properties without significantly affecting bacterial viability. This suggests a potential ecological role for cranberry phenols as non-bactericidal agents capable of modulating pathogenicity of cariogenic biofilms.


Subject(s)
Biofilms/drug effects , Dental Caries , Fruit/chemistry , Plant Extracts/pharmacology , Streptococcus mutans/drug effects , Streptococcus mutans/metabolism , Biofilms/growth & development , Humans , Microbial Sensitivity Tests , Plant Extracts/chemistry , Streptococcus mutans/growth & development
17.
Article in English | MEDLINE | ID: mdl-30510769

ABSTRACT

The term "bacterial dysbiosis" is being used quite extensively in metagenomic studies, however, the identification of harmful bacteria often fails due to large overlap between the bacterial species found in healthy volunteers and patients. We hypothesized that the pathogenic oral bacteria are individual-specific and they correlate with oxidative stress markers in saliva which reflect the inflammatory processes in the oral cavity. Temporally direct and lagged correlations between the markers and bacterial taxa were computed individually for 26 volunteers who provided saliva samples during one month (21.2 ± 2.7 samples/volunteer, 551 samples in total). The volunteers' microbiomes differed significantly by their composition and also by their degree of microbiome temporal variability and oxidative stress markers fluctuation. The results showed that each of the marker-taxa pairs can have negative correlations in some volunteers while positive in others. Streptococcus mutans, which used to be associated with caries before the metagenomics era, had the most prominent correlations with the oxidative stress markers, however, these correlations were not confirmed in all volunteers. The importance of longitudinal samples collections in correlation studies was underlined by simulation of single sample collections in 1000 different combinations which produced contradictory results. In conclusion, the distinct intra-individual correlation patterns suggest that different bacterial consortia might be involved in the oxidative stress induction in each human subject. In the future, decreasing cost of DNA sequencing will allow to analyze multiple samples from each patient, which might help to explore potential diagnostic applications and understand pathogenesis of microbiome-associated oral diseases.

18.
J Med Microbiol ; 66(8): 1244-1252, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28792381

ABSTRACT

Purpose. We assessed the effects of four different types of tea extracts (green, oolong, black and pu-erh tea) on cellular surface properties (hydrophobicity and auto-aggregation) and the colonization attributes (attachment and biofilm formation) of four strains of Candida albicans and three strains of Candida krusei.Methodology. The cellular surface properties were determined using spectrophotometry. The colonization activities were quantified using colorimetric viability assays and visualized using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM).Results. The tea extracts, in general, reduced the hydrophobicity (by 8-66 %) and auto-aggregation (by 20-65 %), and inhibited the attachment of two C. krusei strains (by 41-88 %). Tea extracts enhanced the biofilm formation of one C. albicans and two C. krusei strains (by 1.4-7.5-fold). The observed reduction in hydrophobicity strongly correlated with the reduction in attachment of the two C. krusei strains (P<0.05). The ultrastructural images of the tea-treated C. krusei biofilm cells demonstrated central indentations, although they remained viable.Conclusion. The tea extracts have the ability to retard C. krusei adhesion to glass surfaces, possibly by reducing fungal cellular hydrophobicity, whilst paradoxically promoting biofilm formation. In practical terms, therefore, consumption of tea beverages appears to have a complex effect on oral candidal colonization.

19.
J Org Chem ; 82(15): 8199-8205, 2017 08 04.
Article in English | MEDLINE | ID: mdl-28664732

ABSTRACT

Potassium (K+) exits electrically excitable cells during normal and pathophysiological activity. Currently, K+-sensitive electrodes and electrical measurements are the primary tools to detect K+ fluxes. Here, we describe the synthesis of a near-IR, oxazine fluorescent K+ sensor (KNIR-1) with a dissociation constant suited for detecting changes in intracellular and extracellular K+ concentrations. KNIR-1 treatment of cells expressing voltage-gated K+ channels enabled the visualization of intracellular K+ depletion upon channel opening and restoration of cytoplasmic K+ after channel closing.


Subject(s)
Fluorescent Dyes/chemical synthesis , Oxazines/chemical synthesis , Palladium/chemistry , Potassium/analysis , Animals , CHO Cells , Cricetulus , Fluorescent Dyes/chemistry , Infrared Rays , Molecular Structure , Oxazines/chemistry , Potassium Channels, Voltage-Gated/chemistry , Potassium Channels, Voltage-Gated/metabolism
20.
BMC Res Notes ; 10(1): 257, 2017 Jul 06.
Article in English | MEDLINE | ID: mdl-28683782

ABSTRACT

BACKGROUND: Intake of medicines and supplements is widespread among the professional athletes in developed countries and there are reports to suggest inappropriate self-administration of medicine. Data from South Asia on this area is lacking. This study examined self-medication practices with regard to use of allopathic and herbal/traditional medicines among national -level Sri Lankan athletes. RESULTS: 209 athletes from 15 national sport teams were assessed using an anonymous, interviewer administered questionnaire. Self-medication practices during the 3 months before data collection were evaluated. 60.8% athletes practiced self-medication. 58.3 and 9.4% consumed western and herbal/traditional medicines respectively, while a third used both. The most common symptom for which self-medication was practiced was musculoskeletal pain (73.2%). Oral non-steroidal anti-inflammatory drugs (NSAIDs) and antibiotics were used by 15.7 and 7.1% respectively. Musculoskeletal pain was the predominant symptom that prompted the use of allopathic medicines, while the majority of athletes with upper respiratory tract symptoms being the predominant symptoms, consumed herbal/traditional medicines. Two different commercially available preparations of herbal mixtures were consumed by 15.7 and 15%. Pain prophylaxis during or prior to a sport event was reported by 20.1%, mainly with topical medicines. Medicines were obtained by direct request from a pharmacy without an authorized prescription by a majority (77.2%), followed by using an old prescription in 12.6%. CONCLUSIONS: This study finds that self-medication with both allopathic and herbal/traditional preparations among athletes in a Sri Lanka is high. The use of oral NSAIDs without an authorized prescription in a significant number of athletes is a potential health risk. Frequency of oral NSAID use is lower than that is reported in non-Asian studies from developed countries. The use of herbal/traditional medications increases the likelihood of inadvertent doping. Enhancing awareness regarding risk of such practices among athletes, trainers, pharmacists and prescribers is essential.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Athletes/statistics & numerical data , Musculoskeletal Pain/drug therapy , Plant Preparations/therapeutic use , Self Medication/statistics & numerical data , Adolescent , Adult , Female , Humans , Male , Musculoskeletal Pain/epidemiology , Sri Lanka , Young Adult
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