scholarly journals Role of the oral mucosa in the invasive infection by Candida parapsilsosis sensu stricto, under the condition of dysbiosis

2019 ◽  
Vol 5 (2) ◽  
Author(s):  
Rodríguez ML ◽  
Rosa AC ◽  
Nastri L ◽  
Jewtuchowicz VM
2021 ◽  
Vol 22 (22) ◽  
pp. 12149
Author(s):  
Hector F. Pelaez-Prestel ◽  
Jose L. Sanchez-Trincado ◽  
Esther M. Lafuente ◽  
Pedro A. Reche

The oral mucosa is a site of intense immune activity, where a large variety of immune cells meet to provide a first line of defense against pathogenic organisms. Interestingly, the oral mucosa is exposed to a plethora of antigens from food and commensal bacteria that must be tolerated. The mechanisms that enable this tolerance are not yet fully defined. Many works have focused on active immune mechanisms involving dendritic and regulatory T cells. However, epithelial cells also make a major contribution to tolerance by influencing both innate and adaptive immunity. Therefore, the tolerogenic mechanisms concurring in the oral mucosa are intertwined. Here, we review them systematically, paying special attention to the role of oral epithelial cells.


2021 ◽  
Author(s):  
Mary Yinghua Zhang ◽  
Shuyi Fang ◽  
Hongyu Gao ◽  
Xiaoli Zhang ◽  
Dongsheng Gu ◽  
...  

ABSTRACTWe report our discovery of an important player in the development of skin fibrosis, a hallmark of scleroderma. Scleroderma is a fibrotic disease, affecting 70,000 to 150,000 Americans. Fibrosis is a pathological wound healing process that produces an excessive extracellular matrix to interfere with normal organ function. Fibrosis contributes to nearly half of human mortality. Scleroderma has heterogeneous phenotypes, unpredictable outcomes, no validated biomarkers, and no effective treatment. Thus, strategies to slow down scleroderma progression represent an urgent medical need. While a pathological wound healing process like fibrosis leaves scars and weakens organ function, oral mucosa wound healing is a scarless process. After re-analyses of gene expression datasets from oral mucosa wound healing and skin fibrosis, we discovered that several pathways constitutively activated in skin fibrosis are transiently induced during oral mucosa wound healing process, particularly the amphiregulin (Areg) gene. Areg expression is upregulated ~10 folds 24hrs after oral mucosa wound but reduced to the basal level 3 days later. During bleomycin-induced skin fibrosis, a commonly used mouse model for skin fibrosis, Areg is up-regulated throughout the fibrogenesis and is associated with elevated cell proliferation in the dermis. To demonstrate the role of Areg for skin fibrosis, we used mice with Areg knockout, and found that Areg deficiency essentially prevents bleomycin-induced skin fibrosis. We further determined that bleomycin-induced cell proliferation in the dermis was not observed in the Areg null mice. Furthermore, we found that inhibiting MEK, a downstream signaling effector of Areg, by selumetinib also effectively blocked bleomycin-based skin fibrosis model. Based on these results, we concluded that the Areg-EGFR-MEK signaling axis is critical for skin fibrosis development. Blocking this signaling axis may be effective in treating scleroderma.


2008 ◽  
Vol 19 (3) ◽  
pp. 179-185 ◽  
Author(s):  
Juliana M. Caldeira Brant ◽  
Anilton C. Vasconcelos ◽  
Luciana V. Rodrigues

Oral lichen planus (OLP) is a chronic inflammatory disease with different clinical types. Reticular and erosive forms are the most common. Although the cause of OLP remains speculative, many findings suggest auto-immune involvement, mediated by T lymphocytes against the basal keratinocytes. Inflammation, mechanical trauma or toxic agents can affect the epithelial homeostasia. Increased apoptosis may cause a decrease in epithelial thickness reflecting in the activity of the lesion. The objective of this study was to evaluate the occurrence of apoptosis and epithelial thickness in reticular and erosive forms of OLP. 15 samples of OLP each type (reticular and erosive) plus 10 of healthy mucosa were collected and processed. After morphometry, the apoptotic index and epitelial thickness were obtained. TUNEL and M30 CytoDEATH immunohistochemical assay were used to validate the morphologic criteria used. Apoptosis in the erosive OLP was significantly more intense than in the reticular type and both forms of OLP presented more apoptosis than the healthy oral mucosa. Healthy oral mucosa was thicker than both OLP forms and thicker in OLP reticular form than in the erosive one. The clinical differences between reticular and erosive forms of OLP are related to variations in epithelial thickness and in intensity of apoptosis.


2019 ◽  
Vol 98 (10) ◽  
pp. 1150-1158 ◽  
Author(s):  
W. Chen ◽  
A. Alshaikh ◽  
S. Kim ◽  
J. Kim ◽  
C. Chun ◽  
...  

Oral mucosa provides the first line of defense against a diverse array of environmental and microbial irritants by forming the barrier of epithelial cells interconnected by multiprotein tight junctions (TJ), adherens junctions, desmosomes, and gap junction complexes. Grainyhead-like 2 (GRHL2), an epithelial-specific transcription factor, may play a role in the formation of the mucosal epithelial barrier, as it regulates the expression of the junction proteins. The current study investigated the role of GRHL2 in the Porphyromonas gingivalis ( Pg)–induced impairment of epithelial barrier functions. Exposure of human oral keratinocytes (HOK-16B and OKF6 cells) to Pg or Pg-derived lipopolysaccharides ( Pg LPSs) led to rapid loss of endogenous GRHL2 and the junction proteins (e.g., zonula occludens, E-cadherin, claudins, and occludin). GRHL2 directly regulated the expression levels of the junction proteins and the epithelial permeability for small molecules (e.g., dextrans and Pg bacteria). To explore the functional role of GRHL2 in oral mucosal barrier, we used a Grhl2 conditional knockout (KO) mouse model, which allows for epithelial tissue-specific Grhl2 KO in an inducible manner. Grhl2 KO impaired the expression of the junction proteins at the junctional epithelium and increased the alveolar bone loss in the ligature-induced periodontitis model. Fluorescence in situ hybridization revealed increased epithelial penetration of oral bacteria in Grhl2 KO mice compared with the wild-type mice. Also, blood loadings of oral bacteria (e.g., Bacteroides, Bacillus, Firmicutes, β- proteobacteria, and Spirochetes) were significantly elevated in Grhl2 KO mice compared to the wild-type littermates. These data indicate that Pg bacteria may enhance paracellular penetration through oral mucosa in part by targeting the expression of GRHL2 in the oral epithelial cells, which then impairs the epithelial barrier by inhibition of junction protein expression, resulting in increased alveolar tissue destruction and systemic bacteremia.


2020 ◽  
Vol 9 (11) ◽  
pp. 3641
Author(s):  
Giuseppe A. Scardina ◽  
Giovanni Guercio ◽  
Cesare F. Valenti ◽  
Domenico Tegolo ◽  
Pietro Messina

Introduction: Diabetic foot represents one of the most serious and expensive complications of diabetes and is subject to a high percentage of amputations that are almost always preceded by ulcers ascribable to neuropathy and/or vasculopathy. Videocapillaroscopy (VCS) can be a valuable aid in order to uncover morpho-structural anomalies in the vascular bed, both at the level of the oral mucosa and at the level of the terminal vessels of the lower limb. Materials and methods: Sixty subjects divided into 4 groups were enrolled: 15 healthy subjects; 15 patients with diabetes for more than 10 years without ulcerative foot lesions; 15 patients with neuropathic diabetic foot (clinical diagnosis, MDNS); 15 patients with ischemic diabetic foot (clinical diagnosis, ABI, lower limb doppler). A complete videocapillaroscopic mapping of the oral mucosa was carried out on each patient. The areas investigated were: labial mucosa, the retro-commissural region of the buccal mucosa, and the vestibular masticatory mucosa (II and V sextant). Results: The analysis of the morphological and densitometric characteristics of the capillaries revealed the following: a significant reduction in capillary density in neuropathic (mean ± SD 7.32 ± 2.1) and ischemic patients (mean ± SD 4.32 ± 3.2) compared to the control group of patients (both diabetic mean ± SD 12.98 ± 3.1 and healthy mean ± SD 19.04 ± 3.16) (ANOVA test and Bonferroni t test p < 0.05); a reduction in the average length of the capillaries and a significant increase in tortuosity (ANOVA test and Bonferroni t test p < 0.05). In the neuropathic patients, a recurrent capillaroscopic pattern that we defined as “sun” was found, with capillaries arranged radially around an avascular area. Conclusions: The data obtained from this preliminary study suggest a potential diagnostic role of oral capillaroscopy in the early and subclinical identification of microangiopathic damage in patients with diabetic foot.


2012 ◽  
Vol 78 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Donald E. Fry

Human sepsis is thought to be systemic inflammatory response syndrome (SIRS) that is activated by invasive infection. The multiple organ dysfunction syndrome (MODS) is the identified failure of critical organ function in patients that have sustained SIRS. Because SIRS and MODS are consequences of the excessive activation of inflammation, extensive research and numerous clinical trials have pursued treatments that would modify the inflammatory response. This presentation reviews the normal local mechanisms of inflammation and provides a theoretical framework for the transition of the inflammatory process to a systemic level. Clinical trials with biomodulators to block or inhibit inflammation have generally failed to improve the outcomes in patients with severe sepsis, septic shock, and MODS. The role of counter-inflammatory signaling and the newer concept of the cholinergic anti-inflammatory pathway are being investigated, and newer hypotheses are focusing upon the balancing of proinflammatory and counter-inflammatory mechanisms as important directions for newer therapies. It is concluded that failure to define novel and effective treatments reflects fundamental gaps in our understanding of inflammation and its regulation.


2020 ◽  
Vol 41 (04) ◽  
pp. 455-469 ◽  
Author(s):  
Charles Feldman ◽  
Ronald Anderson

AbstractWith the notable exceptions of the United States and Canada in particular, the global burden of disease in adults due to invasive infection with the dangerous respiratory, bacterial pathogen, Streptococcus pneumoniae (pneumococcus) remains. This situation prevails despite the major successes of inclusion of polysaccharide conjugate vaccines (PCVs) in many national childhood immunization programs and associated herd protection in adults, as well as the availability of effective antimicrobial agents. Accurate assessment of the geographic variations in the prevalence of invasive pneumococcal disease (IPD) has, however, been somewhat impeded by the limitations imposed on the acquisition of reliable epidemiological data due to reliance on often insensitive, laboratory-based, pathogen identification procedures. This, in turn, may result in underestimation of the true burden of IPD and represents a primary focus of this review. Other priority topics include the role of PCVs in the changing epidemiology of IPD in adults worldwide, smoking as a risk factor not only in respect of increasing susceptibility for development of IPD, but also in promoting pneumococcal antibiotic resistance. The theme of pneumococcal antibiotic resistance has been expanded to include mechanisms of resistance to commonly used classes of antibiotics, specifically β-lactams, macrolides and fluoroquinolones, and, perhaps somewhat contentiously, the impact of resistance on treatment outcome. Finally, but no less importantly, the role of persistent antigenemia as a driver of a chronic, subclinical, systemic proinflammatory/procoagulant phenotype that may underpin the long-term sequelae and premature mortality of those adults who have recovered from an episode of IPD, is considered.


2008 ◽  
Author(s):  
A. Kosciarz-Grzesiok ◽  
J. Waskowska ◽  
A. Kawczyk-Krupka ◽  
A. Ledwon ◽  
A. Misiak ◽  
...  
Keyword(s):  

2008 ◽  
Vol 5 (3) ◽  
pp. 182-186 ◽  
Author(s):  
Aleksander Sieroń ◽  
Anna Kościarz-Grzesiok ◽  
Jadwiga Waśkowska ◽  
Aleksandra Kawczyk-Krupka ◽  
Anna Misiak ◽  
...  
Keyword(s):  

2011 ◽  
Vol 11 (4) ◽  
pp. 87-94 ◽  
Author(s):  
Luiz Roberto Ribeiro Faria ◽  
Fernando Amaral da Silveira

The composition of local orchid-bee faunas (Hymenoptera, Apidae, Euglossina) in open-vegetation domains is poorly known, making the ecology and biogeography of the group difficult to understand. The aim of this work was to answer the following questions: i) Is the orchid-bee fauna composition, species richness and abundance in the cerrado (Brazilian savanna) sensu stricto similar to that of riparian forests immersed in that domain? ii) Do species from neighboring forest domains use riparian forests as mesic corridors into the Cerrado? Two sites in cerrado s.s. and two in riparian forests were sampled monthly, one day per month, during one year (Nov/2003-Oct/2004) in northwestern Minas Gerais state, Brazil. Six aromatic compounds (β-ionone, 1,8-cineole, eugenol, methyl trans-cinnamate, methyl salicilate and vanillin) were exposed from 8:00 AM to 4:00 PM to attract orchid bees. The results suggest that: i) The composition of the orchid bee fauna in the two kinds of environments is the same; ii) Riparian forests apparently have no role as mesic corridors for penetration of forest-dependent euglossine species into the core of the Cerrado Domain.


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