scholarly journals A Literature Review and Framework Proposal for Halitosis Assessment in Cigarette Smokers and Alternative Nicotine-Delivery Products Users

2021 ◽  
Vol 2 ◽  
Author(s):  
Filippo Zanetti ◽  
Tanja Zivkovic Semren ◽  
James N. D. Battey ◽  
Philippe A. Guy ◽  
Nikolai V. Ivanov ◽  
...  

Halitosis is a health condition which counts cigarette smoking (CS) among its major risk factors. Cigarette smoke can cause an imbalance in the oral bacterial community, leading to several oral diseases and conditions, including intraoral halitosis. Although the best approach to decrease smoking-related health risks is quitting smoking, this is not feasible for many smokers. Switching to potentially reduced-risk products, like electronic vapor products (EVP) or heated tobacco products (HTP), may help improve the conditions associated with CS. To date, there have been few systematic studies on the effects of CS on halitosis and none have assessed the effects of EVP and HTP use. Self-assessment studies have shown large limitations owing to the lack of reliability in the participants' judgment. This has compelled the scientific community to develop a strategy for meaningful assessment of these new products in comparison with cigarettes. Here, we compiled a review of the existing literature on CS and halitosis and propose a 3-layer approach that combines the use of the most advanced breath analysis techniques and multi-omics analysis to define the interactions between oral bacterial species and their role in halitosis both in vitro and in vivo. Such an approach will allow us to compare the effects of different nicotine-delivery products on oral bacteria and quantify their impact on halitosis. Defining the impact of alternative nicotine-delivery products on intraoral halitosis and its associated bacteria will help the scientific community advance a step further toward understanding the safety of these products and their potentiall risks for consumers.

2020 ◽  
Author(s):  
Li Ping ◽  
Chen Jingchao ◽  
Zhiyu Zhang ◽  
Li Yi ◽  
Liu Lei ◽  
...  

Abstract Background: There is a lack of methodological investigation of the in situ functions of a bacterial species in microecosystems such as the animal gut, although the microbiome has become a focus in the microbiology field worldwide. Results: We used native mixed phages containing Escherichia phages T1 and T4 as a microbial editing tool for eliminating Escherichia coli MG1655 labeled with green fluorescent protein in the mouse gut. The phages possessed rigorous host specificity at both the genus and species levels, resulting in an 8.8-log10 decrease in the titer of viable bacteria after 12 h of phage treatment in an in vitro test. In vivo, they knocked out strain MG1655 not only at concentrations of 10 6 -10 8 CFU g -1 colonizing the mouse gut but also even in mice fed with feedstuff containing the bacterium. In addition, the impact of phage treatment on the microbial community structure of the mouse gut was not significantly ( p >0.05) based on a 16S rRNA amplicon gene sequencing analysis, although the richness of some bacteria changed significantly. Conclusions: We provide a feasible microbial editing technique for the animal gut. Native phages with strict host specificity can effectively knock out a target bacterium by single or continuous gastric perfusion, with limited perturbation of microbial diversity, which is beneficial for studies of the function of a specific bacterial species colonizing a complicated microecosystem.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Susana P. Lopes ◽  
Nuno F. Azevedo ◽  
Maria O. Pereira

Concurrent to conventional bacterial pathogens, unusual microbes are emerging from cystic fibrosis (CF) airways. Nonetheless, little is known about the contribution of these newly microbes to the resilience of CF-associated biofilms, particularly under variable-oxygen concentrations that are known to occurin vivoin the mucus of CF patients. Two CF-emergent bacterial species,Inquilinus limosusandDolosigranulum pigrum, and the major pathogenPseudomonas aeruginosawere studied in terms of biofilm development and antibiotic susceptibilities underin vitroatmospheres with different oxygen availabilities. All species were able to developin vitrobiofilms under different oxygen-available environments, withD. pigrumaccumulating high amounts of biomass and respiratory activities. When established, biofilms were of difficult eradication, with antibiotics losing their effectiveness in comparison with the corresponding planktonic populations. Surprisingly, biofilms of each emergent organism displayed multidrug resistance under aerobic environments, enduring even in low-oxygen atmospheres. This study suggests a potential prospect on the impact of nonconventional organismsI. limosusandD. pigrumon CF lung infections, demonstrating capacity to adapt to biofilm mode of life under restricted-oxygen atmospheres resembling CF airways, which may ultimately endanger the efficacy of currently used antibiotic regimens.


1997 ◽  
Vol 11 (1) ◽  
pp. 81-99 ◽  
Author(s):  
G.H.W. Bowden ◽  
Y.H. Li

The amounts and types of nutrients in the environment influence the development and final bacterial and chemical composition of biofilms. In oligotrophic environments, organisms respond to nutrient stress by alterations in their cell morphology and cell surfaces, which enhance adherence. Little is known of the responses to stress by bacteria in the animal oral cavity. The environment in the oral cavity is less extreme, and saliva provides a constant source of nutrients. Catabolic cooperation among oral bacteria allows carbon and nitrogen from salivary glycoproteins to be utilized. Modification of growth environments of oral bacteria can influence their cell surfaces and adhesion. Studies in experimental animals have shown that feeding either glucose or sucrose diets or fasting has little effect on the initial stages of development of oral biofilms. However, diet can influence the proportions of different bacterial species later in biofilm development. Studies of competition among populations in communities of oral bacteria in vitro and in vivo have shown the significance of carbon limitation and excess and changes in environmental pH. Relatively few studies have been made of the role of a nitrogen metabolism in bacterial competition in biofilms. In keeping with biofilms in nature, oral biofilms provide a sequestered habitat, where organisms are protected from removal by saliva and where interactions among cells generate a biofilm environment, distinct from that of saliva. Oral biofilms are an essential component in the etiologies of caries and periodontal disease, and understanding the biology of oral biofilms has aided and will continue to aid in the prevention and treatment of these diseases.


2021 ◽  
Vol 10 (Supplement_1) ◽  
pp. S9-S9
Author(s):  
M Indriati Hood-Pishchany ◽  
Seth Rakoff-Nahoum

Abstract Background Nutrient utilization is both critical for niche occupation and is the driver of competitive and cooperative interactions in microbial communities. The FRT is replete with host-associated glycans in the form of glycoproteins, epithelial glycogen stores, and the breakdown products of these glycans. I hypothesized that host-associated glycans drive environment, microbe–microbe and host–microbe interactions in the FRT. Methods We have developed robust, scalable, high-throughput culturing systems to empirically define the substrate utilization traits from more than 60 unique bacterial species capable of colonizing the vagina. In addition, we are using batch and continuous culture in vitro cultivation of multispecies communities to study vaginal bacteria within the complex community, that closely recapitulate key dynamics observed in vivo. Results Demonstrating the power of these in vitro models, I have defined the carbohydrate utilization profiles of hundreds of unique FRT isolates, identifying species and strain-level variation in utilization of host-derived carbohydrates. Given the known abundance of glycogen in the vaginal epithelium, I hypothesized that the utilization of host-associated glycogen represents an adaptation to the vaginal environment. Indeed, we identify glycogen degradation enzymes in diverse species resident in the reproductive tract, and find enrichment in genes encoding glycogen-degrading enzymes in L. crispatus strains derived from vaginal as opposed to intestinal sites. Metatranscriptomic analyses from human samples demonstrate that bacterial glycogen and maltose (a breakdown product of glycogen) utilization genes are highly expressed in the vagina and elucidate patterns of gene expression suggestive of context-dependent competition and cooperation for glycogen utilization in vivo. To empirically investigate the impact of glycogen availability and glycogen utilization in FRT microbiota communities, I assembled type strains or co-resident consortia into model, polymicrobial communities in vitro. These studies demonstrate that among health-associated L. crispatus strains, those that use glycogen have a competitive advantage during growth in a complex community. However, preliminary results suggest that some strains may benefit from cross-fed nutrients liberated by other members of the consortium. Conclusions Taken together, these data establish that strain-level variability in glycan utilization contributes to competitive fitness during growth in community, and suggest that these traits may influence community stability or persistence in vivo. Moreover, the methods we have developed provide a scalable system in which to empirically study ecological dynamics within complex community ex vivo.


2006 ◽  
Vol 73 (2) ◽  
pp. 630-636 ◽  
Author(s):  
Natalia I. Chalmers ◽  
Robert J. Palmer ◽  
Laurence Du-Thumm ◽  
Richard Sullivan ◽  
Wenyuan Shi ◽  
...  

ABSTRACT Oral biofilms are multispecies communities, and in their nascent stages of development, numerous bacterial species engage in interspecies interactions. Better insight into the spatial relationship between different species and how species diversity increases over time can guide our understanding of the role of interspecies interactions in the development of the biofilms. Quantum dots (QD) are semiconductor nanocrystals and have emerged as a promising tool for labeling and detection of bacteria. We sought to apply QD-based primary immunofluorescence for labeling of bacterial cells with in vitro and in vivo biofilms and to compare this approach with the fluorophore-based primary immunofluorescence approach we have used previously. To investigate QD-based primary immunofluorescence as the means to detect distinct targets with single-cell resolution, we conjugated polyclonal and monoclonal antibodies to the QD surface. We also conducted simultaneous QD conjugate-based and fluorophore conjugate-based immunofluorescence and showed that these conjugates were complementary tools in immunofluorescence applications. Planktonic and biofilm cells were labeled effectively by considering two factors: the final nanomolar concentration of QD conjugate and the amount of antibody conjugated to the QD, which we define as the degree of labeling. These advances in the application of QD-based immunofluorescence for the study of biofilms in vitro and in vivo will help to define bacterial community architecture and to facilitate investigations of interactions between bacterial species in these communities.


2020 ◽  
Vol 16 (1) ◽  
Author(s):  
Eva Cunha ◽  
Sandra Rebelo ◽  
Carla Carneiro ◽  
Luís Tavares ◽  
Luís Miguel Carreira ◽  
...  

Abstract Background Periodontal disease (PD) in dogs is prompted by the establishment of a polymicrobial biofilm at the tooth surface and a subsequent host inflammatory response. Several strategies may be used for PD control, including dental hygiene home care procedures, like toothbrushing, special diet and chew toys that reduce dental plaque accumulation, or professional periodontal treatments. Aiming at PD control, a biogel composed by nisin and guar-gum was previously developed. This work aimed to establish an in vitro model mimicking the PD-associated biofilms and to evaluate the nisin-biogel inhibitory activity against this polymicrobial biofilm by determining its Minimum Biofilm Inhibitory (MBIC) and Eradication Concentrations (MBEC). Bacterial species tested included Neisseria zoodegmatis CCUG 52598T, Corynebacterium canis CCUG 58627T, Porphyromonas cangingivalis DSMZ VPB 4874, Peptostreptococcus canis CCUG 57081 and an Enterococcus faecalis isolate belonging to a collection of oral bacteria obtained from dogs with PD. Before establishing the biofilm, coaggregation between species was determined by optical density measurement after 2 and 24 hours. Nisin-biogel MBIC and MBEC values regarding the polymicrobial biofilm were determined using a modified version of the Calgary biofilm pin lid device, after confirming the presence of the five bacterial species by Fluorescent In Situ Hybridization. Results Only 40% of the bacterial dual suspensions were able to coaggregate at 2 hours, but all species tested exhibited a coaggregation percentage higher than 30% at 24 hours. It was possible to establish a 48 h polymicrobial biofilm model composed by the five bacterial species selected. This model was used to determine nisin-biogel MBIC (26.39 ± 5.89 µg/mL) and MBEC (62.5 ± 27.73 µg/mL) values. Conclusions Our results showed that the nisin-biogel can inhibit and eradicate PD multispecies biofilms. As this in vitro model mimics an in vivo periodontal polymicrobial biofilm, our results reinforce the potential of the application of nisin-biogel for canine PD control.


2018 ◽  
Vol 85 (2) ◽  
Author(s):  
Andrew J. Sommer ◽  
Peter D. Newell

ABSTRACTInteractions between species shape the formation and function of microbial communities. In the gut microbiota of animals, cross-feeding of metabolites between microbes can enhance colonization and influence host physiology. We examined a mutually beneficial interaction between two bacteria isolated from the gut microbiota ofDrosophila, i.e.,Acetobacter fabarumandLactobacillus brevis. After developing anin vitrococulture assay, we utilized a genetic screen to identifyA. fabarumgenes required for enhanced growth withL. brevis. The screen, and subsequent genetic analyses, showed that the gene encoding pyruvate phosphate dikinase (ppdK) is required forA. fabarumto benefit fully from coculture. By testing strains with mutations in a range of metabolic genes, we provide evidence thatA. fabarumcan utilize multiple fermentation products ofL. brevis. Mutualism between the bacteriain vivoaffects gnotobioticDrosophila melanogaster; flies associated withA. fabarumandL. brevisshowed >1,000-fold increases in bacterial cell density and significantly lower triglyceride storage than monocolonized flies. Mutation ofppdKdecreasedA. fabarumdensity in flies cocolonized withL. brevis, consistent with the model in whichAcetobacteremploys gluconeogenesis to assimilateLactobacillusfermentation products as a source of carbonin vivo. We propose that cross-feeding between these groups is a common feature of microbiota inDrosophila.IMPORTANCEThe digestive tracts of animals are home to a community of microorganisms, the gut microbiota, which affects the growth, development, and health of the host. Interactions among microbes in this inner ecosystem can influence which species colonize the gut and can lead to changes in host physiology. We investigated a mutually beneficial interaction between two bacterial species from the gut microbiota of fruit flies. By coculturing the bacteriain vitro, we were able to identify a metabolic gene required for the bacteria to grow better together than they do separately. Our data suggest that one species consumes the waste products of the other, leading to greater productivity of the microbial community and modifying the nutrients available to the host. This study provides a starting point for investigating how these and other bacteria mutually benefit by sharing metabolites and for determining the impact of mutualism on host health.


Author(s):  
V. Ramadas ◽  
G. Chandralega

Sponges, exclusively are aquatic and mostly marine, are found from the deepest oceans to the edge of the sea. There are approximately 15,000 species of sponges in the world, of which, 150 occur in freshwater, but only about 17 are of commercial value. A total of 486 species of sponges have been identified in India. In the Gulf of Mannar and Palk Bay a maximum of 319 species of sponges have been recorded. It has been proved that marine organisms are excellent source of bioactive secondary metabolites and number of compounds of originated from marine organisms had been reported to possess in-vitro and in-vivo immuno stimulatory activity. Extracts from 20 sponge species were tested for bacterial symbionts and bioactive compounds were isolated from such associated bacterial species in the present study.


2013 ◽  
Vol 150 (3) ◽  
pp. 1024-1031 ◽  
Author(s):  
Mohammad Hossein Boskabady ◽  
Sakine Shahmohammadi Mehrjardi ◽  
Abadorrahim Rezaee ◽  
Houshang Rafatpanah ◽  
Sediqeh Jalali

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hiroaki Kanzaki ◽  
Tetsuhiro Chiba ◽  
Junjie Ao ◽  
Keisuke Koroki ◽  
Kengo Kanayama ◽  
...  

AbstractFGF19/FGFR4 autocrine signaling is one of the main targets for multi-kinase inhibitors (MKIs). However, the molecular mechanisms underlying FGF19/FGFR4 signaling in the antitumor effects to MKIs in hepatocellular carcinoma (HCC) remain unclear. In this study, the impact of FGFR4/ERK signaling inhibition on HCC following MKI treatment was analyzed in vitro and in vivo assays. Serum FGF19 in HCC patients treated using MKIs, such as sorafenib (n = 173) and lenvatinib (n = 40), was measured by enzyme-linked immunosorbent assay. Lenvatinib strongly inhibited the phosphorylation of FRS2 and ERK, the downstream signaling molecules of FGFR4, compared with sorafenib and regorafenib. Additional use of a selective FGFR4 inhibitor with sorafenib further suppressed FGFR4/ERK signaling and synergistically inhibited HCC cell growth in culture and xenograft subcutaneous tumors. Although serum FGF19high (n = 68) patients treated using sorafenib exhibited a significantly shorter progression-free survival and overall survival than FGF19low (n = 105) patients, there were no significant differences between FGF19high (n = 21) and FGF19low (n = 19) patients treated using lenvatinib. In conclusion, robust inhibition of FGF19/FGFR4 is of importance for the exertion of antitumor effects of MKIs. Serum FGF19 levels may function as a predictive marker for drug response and survival in HCC patients treated using sorafenib.


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