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BioMed Research International 2020
Topics: Humans; Mouth; Mouth Diseases
PubMed: 32596322
DOI: 10.1155/2020/5273046 -
Journal of Biotechnology May 2017Infections induced by oral biofilms include caries, as well as periodontal, and peri-implant disease, and may influence quality of life, systemic health, and... (Review)
Review
Infections induced by oral biofilms include caries, as well as periodontal, and peri-implant disease, and may influence quality of life, systemic health, and expenditure. As bacterial biofilms are highly resistant and resilient to conventional antibacterial therapy, it has been difficult to combat these infections. An innovative alternative to the biocontrol of oral biofilms could be to use bacteriophages or phages, the viruses of bacteria, which are specific, non-toxic, self-proliferating, and can penetrate into biofilms. Phages for Actinomyces naeslundii, Aggregatibacter actinomycetemcomitans, Enterococcus faecalis, Fusobacterium nucleatum, Lactobacillus spp., Neisseria spp., Streptococcus spp., and Veillonella spp. have been isolated and characterised. Recombinant phage enzymes (lysins) have been shown to lyse A. naeslundii and Streptococcus spp. However, only a tiny fraction of available phages and their lysins have been explored so far. The unique properties of phages and their lysins make them promising but challenging antimicrobials. The genetics and biology of phages have to be further explored in order to determine the most effective way of applying them. Studying the effect of phages and lysins on multispecies biofilms should pave the way for microbiota engineering and microbiota-based therapy.
Topics: Bacterial Infections; Bacteriophages; Biofilms; Humans; Mouth; Mouth Diseases
PubMed: 28108235
DOI: 10.1016/j.jbiotec.2017.01.002 -
Current Issues in Molecular Biology Jul 2005The oral cavity is a unique environment in which antimicrobial peptides play a key role in maintaining health and may have future therapeutic applications. Present... (Review)
Review
The oral cavity is a unique environment in which antimicrobial peptides play a key role in maintaining health and may have future therapeutic applications. Present evidence suggests that alpha-defensins, beta-defensins, LL-37, histatin, and other antimicrobial peptides and proteins have distinct but overlapping roles in maintaining oral health and preventing bacterial, fungal, and viral adherence and infection. The expression of the inducible hBD-2 in normal oral epithelium, in contrast to other epithelia, and the apparent differential signaling in response to commensal and pathogenic organisms, provides new insights into innate immunity in this body site. Commensal bacteria are excellent inducers of hBD-2 in oral epithelial cells, suggesting that the commensal bacterial community acts in a manner to benefit the overall innate immune readiness of oral epithelia. This may have major significance for understanding host defense in the complex oral environment.
Topics: Animals; Anti-Bacterial Agents; Antimicrobial Cationic Peptides; Epithelium; Gingiva; Immunity, Innate; Mice; Mouth Mucosa
PubMed: 16053246
DOI: 10.1093/jac/dki103 -
Anais Brasileiros de Dermatologia 2024Several topics related to the oral cavity are briefly addressed in this article, from anatomical variations that, when recognized, avoid unnecessary investigations, to...
Several topics related to the oral cavity are briefly addressed in this article, from anatomical variations that, when recognized, avoid unnecessary investigations, to diseases that affect exclusively the mouth, mucocutaneous diseases, as well as oral manifestations of systemic diseases. A complete clinical examination comprises the examination of the mouth, and this approach facilitates clinical practice, shortening the path to diagnosis in the outpatient clinic as well as with in-hospital patients. The objective of this article is to encourage the examination of the oral cavity as a useful tool in medical practice, helping to recognize diseases in this location.
Topics: Humans; Mouth Diseases; Oral Ulcer; Mouth; Mouth Mucosa
PubMed: 37722995
DOI: 10.1016/j.abd.2023.06.001 -
Microbiology Spectrum Feb 2023species are abundant members of the human oral microbiome with multiple interspecies commensal relationships. Examining the distribution patterns of species across the...
species are abundant members of the human oral microbiome with multiple interspecies commensal relationships. Examining the distribution patterns of species across the oral cavity is fundamental to understanding their oral ecology. In this study, we used a combination of pangenomic analysis and oral metagenomic information to clarify taxonomy and to test the site specialist hypothesis for the genus, which contends that most oral bacterial species are adapted to live at specific oral sites. Using isolate genome sequences combined with shotgun metagenomic sequence data, we showed that species have clear, differential site specificity: Veillonella parvula showed strong preference for supra- and subgingival plaque, while closely related V. dispar, as well as more distantly related V. atypica, preferred the tongue dorsum, tonsils, throat, and hard palate. In addition, the provisionally named sp. Human Microbial Taxon 780 showed strong site specificity for keratinized gingiva. Using comparative genomic analysis, we identified genes associated with thiamine biosynthesis and the reductive pentose phosphate cycle that may enable species to occupy their respective habitats. Understanding the microbial ecology of the mouth is fundamental for understanding human physiology. In this study, metapangenomics demonstrated that different species have clear ecological preferences in the oral cavity of healthy humans, validating the site specialist hypothesis. Furthermore, the gene pool of different species was found to be reflective of their ecology, illuminating the potential role of vitamins and carbohydrates in determining distribution patterns and interspecies interactions.
Topics: Humans; Veillonella; Mouth; Tongue; Palatine Tonsil; Microbiota
PubMed: 36695592
DOI: 10.1128/spectrum.04042-22 -
Scientific Reports Apr 2021Shammah is a smokeless tobacco product often mixed with lime, ash, black pepper and flavorings. Exposure to shammah has been linked with dental diseases and oral...
Shammah is a smokeless tobacco product often mixed with lime, ash, black pepper and flavorings. Exposure to shammah has been linked with dental diseases and oral squamous cell carcinoma. There is limited literature on the prevalence of shammah and its role in pathobiology of oral cancer. In this study, we developed a cellular model to understand the effect of chronic shammah exposure on oral keratinocytes. Chronic exposure to shammah resulted in increased proliferation and invasiveness of non-transformed oral keratinocytes. Quantitative proteomics of shammah treated cells compared to untreated cells led to quantification of 4712 proteins of which 402 were found to be significantly altered. In addition, phosphoproteomics analysis of shammah treated cells compared to untreated revealed hyperphosphorylation of 36 proteins and hypophosphorylation of 83 proteins (twofold, p-value ≤ 0.05). Bioinformatics analysis of significantly altered proteins showed enrichment of proteins involved in extracellular matrix interactions, necroptosis and peroxisome mediated fatty acid oxidation. Kinase-Substrate Enrichment Analysis showed significant increase in activity of kinases such as ROCK1, RAF1, PRKCE and HIPK2 in shammah treated cells. These results provide better understanding of how shammah transforms non-neoplastic cells and warrants additional studies that may assist in improved early diagnosis and treatment of shammah induced oral cancer.
Topics: Cells, Cultured; Humans; Keratinocytes; Mouth; Phosphoproteins; Proteome; Signal Transduction; Tobacco, Smokeless
PubMed: 33931671
DOI: 10.1038/s41598-021-88345-x -
International Journal of Molecular... Oct 2020Nitric oxide (NO), a small gaseous and multifunctional signaling molecule, is involved in the maintenance of metabolic and cardiovascular homeostasis. It is endogenously... (Review)
Review
Nitric oxide (NO), a small gaseous and multifunctional signaling molecule, is involved in the maintenance of metabolic and cardiovascular homeostasis. It is endogenously produced in the vascular endothelium by specific enzymes known as NO synthases (NOSs). Subsequently, NO is readily oxidized to nitrite and nitrate. Nitrite is also derived from exogenous inorganic nitrate (NO) contained in meat, vegetables, and drinking water, resulting in greater plasma NO concentration and major reduction in systemic blood pressure (BP). The recycling process of nitrate and nitrite to NO (nitrate-nitrite-NO pathway), known as the enterosalivary cycle of nitrate, is dependent upon oral commensal nitrate-reducing bacteria of the dorsal tongue. , , , and are the most copious among the nitrate-reducing bacteria. The use of chlorhexidine mouthwashes and tongue cleaning can mitigate the bacterial nitrate-related BP lowering effects. Imbalances in the oral reducing microbiota have been associated with a decrease of NO, promoting endothelial dysfunction, and increased cardiovascular risk. Although there is a relationship between periodontitis and hypertension (HT), the correlation between nitrate-reducing bacteria and HT has been poorly studied. Restoring the oral flora and NO activity by probiotics may be considered a potential therapeutic strategy to treat HT.
Topics: Animals; Blood Pressure; Gastrointestinal Microbiome; Humans; Mouth; Nitric Oxide; Periodontal Diseases
PubMed: 33066082
DOI: 10.3390/ijms21207538 -
Australian Dental Journal Mar 2006Cryotherapy is the deliberate destruction of tissue by application of extreme cold. It is well received by patients due to a relative lack of discomfort, the absence of... (Review)
Review
Cryotherapy is the deliberate destruction of tissue by application of extreme cold. It is well received by patients due to a relative lack of discomfort, the absence of bleeding and minimal to no scarring after healing. It has many applications in oral medicine and clinical oral pathology, and is extremely usefu in patients for whom surgery is contra-indicated due to either age or medical history. In this paper we outline the principles, mechanisms of action, and current applications of cryotherapy in the treatment of oral lesions, and present some clinical cases.
Topics: Cryosurgery; Humans; Mouth Diseases; Mouth Mucosa
PubMed: 16669469
DOI: 10.1111/j.1834-7819.2006.tb00392.x -
Experimental Physiology Feb 2020What is the central question of this study? Does the parafacial respiratory group (pFRG), which mediates active expiration, recruit nasofacial and oral motoneurons to...
NEW FINDINGS
What is the central question of this study? Does the parafacial respiratory group (pFRG), which mediates active expiration, recruit nasofacial and oral motoneurons to coordinate motor activities that engage muscles controlling airways in rats during active expiration. What is the main finding and its importance? Hypercapnia/acidosis or pFRG activation evoked active expiration and stimulated the motoneurons and nerves responsible for the control of nasofacial and oral airways patency simultaneously. Bilateral pFRG inhibition abolished active expiration and the simultaneous nasofacial and oral motor activities induced by hypercapnia/acidosis. The pFRG is more than a rhythmic oscillator for expiratory pump muscles: it also coordinates nasofacial and oral motor commands that engage muscles controlling airways.
ABSTRACT
Active expiration is mediated by an expiratory oscillator located in the parafacial respiratory group (pFRG). Active expiration requires more than contracting expiratory muscles as multiple cranial nerves are recruited to stabilize the naso- and oropharyngeal airways. We tested the hypothesis that activation of the pFRG recruits facial and trigeminal motoneurons to coordinate nasofacial and oral motor activities that engage muscles controlling airways in rats during active expiration. Using a combination of electrophysiological and pharmacological approaches, we identified brainstem circuits that phase-lock active expiration, nasofacial and oral motor outputs in an in situ preparation of rat. We found that either high chemical drive (hypercapnia/acidosis) or unilateral excitation (glutamate microinjection) of the pFRG evoked active expiration and stimulated motoneurons (facial and trigeminal) and motor nerves responsible for the control of nasofacial (buccal and zygomatic branches of the facial nerve) and oral (mylohyoid nerve) motor outputs simultaneously. Bilateral pharmacological inhibition (GABAergic and glycinergic receptor activation) of the pFRG abolished active expiration and the simultaneous nasofacial and oral motor activities induced by hypercapnia/acidosis. We conclude that the pFRG provides the excitatory drive to phase-lock rhythmic nasofacial and oral motor circuits during active expiration in rats. Therefore, the pFRG is more than a rhythmic oscillator for expiratory pump muscles: it also coordinates nasofacial and oral motor commands that engage muscles controlling airways in rats during active expiration.
Topics: Animals; Exhalation; Facial Muscles; Male; Motor Activity; Motor Neurons; Mouth; Nasal Cavity; Rats; Rats, Wistar; Respiratory Center
PubMed: 31820827
DOI: 10.1113/EP088046 -
Viruses Mar 2021This study is focused on the epidemiological characteristics and biomolecular mechanisms that lead to the development of precancerous and cancerous conditions of oral... (Review)
Review
This study is focused on the epidemiological characteristics and biomolecular mechanisms that lead to the development of precancerous and cancerous conditions of oral lesions related to Human Papilloma Virus (HPV) infections. Current evidence from the literature demonstrates the role of HPV in potentially malignant oral disorders. Therefore, the underlying biomolecular processes can give arise, or contribute to, benign lesions as well as to oral carcinogenesis.
Topics: Carcinogenesis; Humans; Microbiota; Mouth; Mouth Neoplasms; Papillomaviridae; Papillomavirus Infections
PubMed: 33810374
DOI: 10.3390/v13040559