Phyllanthus emblica fruit extract alleviates halitosis and reduces the inflammatory response to oral bacteria.

OBJECTIVE: To assess the efficacy of Phyllanthus emblica extract in alleviating halitosis and reducing the inflammatory response to halitosis-related bacteria. METHODOLOGY: This investigation, using Phyllanthus emblica fruit extract (PE), involved four aspects. First, we evaluated the effect on growth and aggregation of halitosis-related bacteria, including Fusobacterium nucleatum, Porphyromonas gingivalis, and Solobacterium moorei, using a microdilution assay and scanning electron microscopy. Second, volatile sulfur compound (VSC) levels were measured on individuals with halitosis in randomized short-term (26 participants) and double-blind randomized long-term trials (18 participants in each group) after rinsing with PE for 3, 6, and 12 h, and 28 days. Third, we analyzed pro-inflammatory cytokine expression in TR146 cells using quantitative real-time PCR and enzyme-linked immunosorbent assays. Lastly, we assessed pro-inflammatory cytokine secretion and Toll-like receptor (TLR) 2 mRNA expression via the same experimental methods in a three-dimensional oral mucosal epithelial model (3D OMEM). RESULTS: PE extract dose-dependently inhibited the growth of F. nucleatum (50% inhibition concentration [IC50]=0.079%), P. gingivalis (IC50=0.65%), and S. moorei (IC50=0.07%) and effectively prevented bacterial aggregation. Furthermore, VSC contents decreased significantly at 3, 6, and 12 h after rinsing with 5% PE compared with those in the control. Long-term use of mouthwash containing 5% PE for 28 days led to a significant decrease in VSC contents. PE attenuated the F. nucleatum- or P. gingivalis-stimulated mRNA expression and protein release of interleukin (IL)-6 and IL-8 in TR146 cells. It also suppressed IL-8 and prostaglandin E2 secretion and TLR2 mRNA expression in F. nucleatum-induced OMEMs. CONCLUSION: Our findings support the use of PE in oral care products to alleviate halitosis and it may reduce inflammation.

Mucoadhesive delivery systems for oral candidiasis treatment: A systematic review and meta-analysis.

OBJECTIVES: This systematic review and meta-analysis aimed to evaluate the clinical and mycological effectiveness of mucoadhesives as vehicles for drugs or natural products in the treatment of oral candidiasis. MATERIALS AND METHODS: The search for articles was carried out in the Medline/PubMed, SCOPUS, EMBASE, Web of Science, Cochrane Library, and SciELO databases before August 2023. We selected the studies, extracted the data, evaluated the study quality, graded the evidence, performed the risk of bias, and carried out meta-analysis. RESULTS: A total of 389 potentially relevant articles were identified, and 11 studies (1869 participants) met the inclusion criteria of the systematic review. The overall risk of bias was considered low. The most common presentation of mucoadhesives was tablets, with miconazole being the most frequently drug used in the delivery system. Mucoadhesives demonstrated comparable efficacy with topical or systemic antifungal agents, with no significant differences between treatments in terms of clinical (RR = 0.907; 95CI = 0.3-1.297; p = 0.591; I2 = 64.648) or mycological (RR = 0.95; 95CI = 0.667-1.360; p = 0.789; I2 = 73.271) efficacy. CONCLUSIONS: Mucoadhesives may be a suitable alternative to conventional treatments, with the advantage of reducing the frequency of application by up to 5 times and the daily dosage by up to 20 times.

Commensal oral microbiota impacts ulcerative oral mucositis clinical course in allogeneic stem cell transplant recipients.

Oral mucositis (OM) is a complex acute cytotoxicity of antineoplastic treatment that affects 40-85% of patients undergoing hematopoietic stem-cell transplantation. OM is associated with prolonged hospitalization, increased extensive pharmacotherapy, need for parenteral nutrition, and elevated treatment costs. As OM onset relates to the mucosal microenvironment status, with a particular role for microbiota-driven inflammation, we aimed to investigate whether the oral mucosa microbiota was associated with the clinical course of OM in patients undergoing allogeneic hematopoietic stem-cell transplantation. We collected oral mucosa samples from 30 patients and analyzed the oral mucosa microbiota by 16S rRNA sequencing. A total of 13 patients (43%) developed ulcerative OM. We observed that specific taxa were associated with oral mucositis grade and time to oral mucositis healing. Porphyromonas relative abundance at preconditioning was positively correlated with ulcerative OM grade (Spearman ρ = 0.61, P = 0.028) and higher Lactobacillus relative abundance at ulcerative OM onset was associated with shortened ulcerative OM duration (P = 0.032). Additionally, we generated a machine-learning-based bacterial signature that uses pre-treatment microbial profiles to predict whether a patient will develop OM during treatment. Our findings suggest that further research should focus on host-microbiome interactions to better prevent and treat OM.

Disruption of the oral microbiota is associated with a higher risk of relapse after allogeneic hematopoietic stem cell transplantation.

Intestinal microbiota (IM) diversity and composition regulates host immunity and affects outcomes after allogeneic stem cell transplantation (allo-HSCT). We evaluated if the oral mucosa microbiota (OM) could impact the outcomes in patients who underwent allo-HSCT. Samples from the oral mucosa of 30 patients were collected at three time points: before the conditioning regimen, at aplasia, and at engraftment. We analyzed the associations of OM diversity and composition with allo-HSCT outcomes. Lower OM diversity at preconditioning was associated with a higher risk of relapse at 3 years (68% versus 33%, respectively; P = 0.04). Dominance (relative abundance ≥ 30%) by a single genus at preconditioning was also associated with a higher risk of relapse (63% versus 36% at 3 years, respectively; P = 0.04), as well as worse progression-free survival (PFS; 19% versus 55%, respectively; P = 0.01), and overall survival (OS) at 3 years (38% versus 81%, respectively; P = 0.02). In our study we observed that OM dysbiosis is associated with a higher risk of relapse and worse survival after allo-HSCT.

Role of Tonsillar Chronic Inflammation and Commensal Bacteria in the Pathogenesis of Pediatric OSA.

Immune responses at the boundary between the host and the world beyond are complex and mucosal tissue homeostasis relies on them. Obstructive sleep apnea (OSA) is a syndrome suffered by children with hypertrophied tonsils. We have previously demonstrated that these tonsils present a defective regulatory B cell (Breg) compartment. Here, we extend those findings by uncovering the crucial role of resident pro-inflammatory B and T cells in sustaining tonsillar hypertrophy and hyperplasia by producing TNFα and IL17, respectively, in ex vivo cultures. Additionally, we detected prominent levels of expression of CD1d by tonsillar stratified as well as reticular epithelium, which have not previously been reported. Furthermore, we evidenced the hypertrophy of germinal centers (GC) and the general hyperplasia of B lymphocytes within the tissue and the lumen of the crypts. Of note, such B cells resulted mainly (IgG/IgM)+ cells, with some IgA+ cells located marginally in the follicles. Finally, by combining bacterial culture from the tonsillar core and subsequent identification of the respective isolates, we determined the most prevalent species within the cohort of OSA patients. Although the isolated species are considered normal oropharyngeal commensals in children, we confirmed their capacity to breach the epithelial barrier. Our work sheds light on the pathological mechanism underlying OSA, highlighting the relevance taken by the host immune system when defining infection versus colonization, and opening alternatives of treatment.

Molecular detection of Mycobacterium tuberculosis from buccal swabs among adult in Peru.

Tuberculosis (TB) diagnosis relies on a sputum sample, which cannot be easily obtained from all symptomatic patients. Mycobacterium tuberculosis DNA can be detected from oral swabs, a noninvasive, safe alternative sample type; however, reported sensitivities have been variable and likely depend on sample collection, processing procedures and host characteristics. We analyzed three buccal swab samples from 123 adults with culture-confirmed TB in Lima, Peru. We compared the sensitivity and specificity of two sample collection devices (OmniSwab and EasiCollect FTA cards) and examined factors associated with detection. DNA was extracted with a commercially available kit and detected via real-time PCR IS6110 amplification. Overall sensitivity for buccal samples was 51% (95% Confidence Interval [CI] 42-60%). Specificity from a single sample among healthy controls was 96.7% (95% CI 83-99.9%). Positive sputum smear and cavitary disease, correlates of disease burden, were associated with detection via buccal swab. Although we observed higher sensitivities with the Omniswab samples, this appeared to be due primarily to differences in patient characteristics (e.g., cavitary disease). Overall, our findings support the potential for a buccal sample-based TB assay. Future work should focus on assay optimization and streamlining the assay workflow.

Bifidobacterium animalis subsp lactis HN019 presents antimicrobial potential against periodontopathogens and modulates the immunological response of oral mucosa in periodontitis patients.

OBJECTIVE: To evaluate the effects of Bifidobacterium animalis subsp. lactis HN019 (HN019) on clinical periodontal parameters (plaque accumulation and gingival bleeding), on immunocompetence of gingival tissues [expression of beta-defensin (BD)-3, toll-like receptor 4 (TLR4), cluster of differentiation(CD)-57 and CD-4], and on immunological properties of saliva (IgA levels) in non-surgical periodontal therapy in generalized chronic periodontitis (GCP) patients. Adhesion to buccal epithelial cells (BEC) and the antimicrobial properties of HN019 were also investigated. MATERIALS AND METHODS: Thirty patients were recruited and monitored clinically at baseline (before scaling and root planing-SRP) and after 30 and 90 days. Patients were randomly assigned to Test (SRP+Probiotic, n = 15) or Control (SRP+Placebo, n = 15) group. Probiotic lozenges were used for 30 days. Gingival tissues and saliva were immunologically analyzed. The adhesion of HN019 with or without Porphyromonas gingivalis in BEC and its antimicrobial properties were investigated in in vitro assays. Data were statistically analyzed (p<0.05). RESULTS: Test group presented lower plaque index (30 days) and lower marginal gingival bleeding (90 days) when compared with Control group. Higher BD-3, TLR4 and CD-4 expressions were observed in gingival tissues in Test group than in Control group. HN019 reduced the adhesion of P. gingivalis to BEC and showed antimicrobial potential against periodontopathogens. CONCLUSION: Immunological and antimicrobial properties of B. lactis HN019 make it a potential probiotic to be used in non-surgical periodontal therapy of patients with GCP. CLINICAL RELEVANCE: B. lactis HN019 may be a potential probiotic to improve the effects of non-surgical periodontal therapy. Name of the registry and registration number (ClinicalTrials.gov): "Effects of probiotic therapy in the treatment of periodontitis"-NCT03408548.

Enzyme production by Candida albicans and Candida dubliniensis in periodontal HIV-positive patients receiving and not receiving antiretroviral therapy.

Candida dubliniensis (Cd) and Candida albicans (Ca) are the most frequently isolated yeasts in HIV+ patients. Some of the enzymes produced by these yeasts are considered virulence factors since they contribute to pathogenicity of Candida spp. The aim of the present study was to compare production of enzymes such as phospholipase (Ph), proteinase (P), and hemolysin (H) by Cd and Ca strains isolated from periodontal HIV-positive patients receiving and not receiving highly active antiretroviral therapy (HAART). Subgingival biofilm samples were obtained using paper points, and a sample of oral mucosa was taken using a swab. Phenotypic and molecular methods were used to isolate 39 strains of Candida, including 25 strains of Cd and 14 strains of Ca, obtained from 33 periodontal pocket samples and 6 oral mucosa samples collected from 15 HIV+ patients (8 receiving and 7 not receiving HAART). Malt egg-yolk agar, albumin agar and blood agar were used to evaluate pH, P and H production respectively. The strains were inoculated in duplicate and incubated at 37 ºC. Colony and halo diameters were measured. A greater proportion of Ca was observed in patients not receiving HAART, and a higher proportion of Cd was observed in those under HAART, Chi2 p< 0.001. Phospholipase production was observed in 92.9% percent of isolated Ca strains but in none of the isolated Cd strains. Proteinase production was high in Ca and Cd strains isolated from patients not receiving HAART. Hemolysin production was observed in all the studied strains, though it was significantly higher (p=0.04) in Ca and Cd strains isolated from patients not receiving HAART. To sum up, the proportion of Candida dubliniensis strains was highest in the subgingival biofilm of patients receiving HAART, and Cd strains were found to express fewer virulence factors than Ca strains.

Las levaduras más aisladas en pacientes VIH+ son Candida dubliniensis (Cd) y Candida albicans (Ca). Algunas de sus enzimas constituyen factores de virulencia ya que favorecen la diseminación tisular. El objetivo fue comparar la producción de enzimas como fosfolipasa (F), proteinasa (P) y hemolisina (H) en cepas de Cd y Ca aisladas de pacientes VIH+ tratados y no tratados con antirretrovirales (TARGA). Se realizó la toma del biofilm de placa subgingival con conos de papel y la muestra de la mucosa bucal con hisopo. Se aislaron y tipificaron por métodos fenotípicos y moleculares 39 cepas: 25 de Cd y 14 Ca, obtenidas 33 de bolsas periodontales y 6 de mucosa bucal de 15 pacientes VIH+ (8 con y 7 sin tratamiento). Se utilizó agar malta con yema de huevo, agar albúmina y agar sangre para demostrar la producción de F, P y H, respectivamente. Se inocularon por duplicado e incubaron a 37°C. Se midieron los diámetros de las colonias y los de hidrólisis alrededor de las mismas. Se observó mayor proporción de Ca en los pacientes sin tratamiento y mayor proporción de Cd en los con tratamiento; Chi2 p< 0.001. El 92,9% de las Ca estudiadas, fueron productoras de fosfolipasa. En tanto que ninguna Cd produjo la enzima. En cuanto a la producción de proteinasa se observa una alta producción tanto en las cepas de Ca, como en las Cd aisladas en los pacientes no tratados. Todas las cepas estudiadas produjeron hemolisina, observándose una diferencia estadísticamente significativa (p=0,04) en ambas especies a favor de la alta producción de la enzima en las cepas obtenidas de pacientes no tratados. Podemos concluir que en el biofilm subgingival, en los pacientes bajo TARGA, se aíslan mayor proporción de Candida dubliniensis las cuales expresan menos factores de virulencia.

Enzyme production by Candida albicans and Candida dubliniensis in periodontal HIV-positive patients receiving and not receiving antiretroviral therapy / Producción enzimática de Candida albicans y Candida dubliniensis de pacientes con periodontitis VIH+ con y sin tratamiento antirretroviral

ABSTRACT Candida dubliniensis (Cd) and Candida albicans (Ca) are the most frequently isolated yeasts in HIV+ patients. Some of the enzymes produced by these yeasts are considered virulence factors since they contribute to pathogenicity of Candida spp. The aim of the present study was to compare production of enzymes such as phospholipase (Ph), proteinase (P), and hemolysin (H) by Cd and Ca strains isolated from periodontal HIV-positive patients receiving and not receiving highly active antiretroviral therapy (HAART). Subgingival biofilm samples were obtained using paper points, and a sample of oral mucosa was taken using a swab. Phenotypic and molecular methods were used to isolate 39 strains of Candida, including 25 strains of Cd and 14 strains of Ca, obtained from 33 periodontal pocket samples and 6 oral mucosa samples collected from 15 HIV+ patients (8 receiving and 7 not receiving HAART). Malt egg-yolk agar, albumin agar and blood agar were used to evaluate pH, P and H production respectively. The strains were inoculated in duplicate and incubated at 37 ºC. Colony and halo diameters were measured. A greater proportion of Ca was observed in patients not receiving HAART, and a higher proportion of Cd was observed in those under HAART, Chi2 p< 0.001. Phospholipase production was observed in 92.9% percent of isolated Ca strains but in none of the isolated Cd strains. Proteinase production was high in Ca and Cd strains isolated from patients not receiving HAART. Hemolysin production was observed in all the studied strains, though it was significantly higher (p=0.04) in Ca and Cd strains isolated from patients not receiving HAART. To sum up, the proportion of Candida dubliniensis strains was highest in the subgingival biofilm of patients receiving HAART, and Cd strains were found to express fewer virulence factors than Ca strains.

RESUMEN Las levaduras más aisladas en pacientes VIH+ son Candida dubliniensis (Cd) y Candida albicans (Ca). Algunas de sus enzimas constituyen factores de virulencia ya que favorecen la diseminación tisular. El objetivo fue comparar la producción de enzimas como fosfolipasa (F), proteinasa (P) y hemolisina (H) en cepas de Cd y Ca aisladas de pacientes VIH+ tratados y no tratados con antirretrovirales (TARGA). Se realizó la toma del biofilm de placa subgingival con conos de papel y la muestra de la mucosa bucal con hisopo. Se aislaron y tipificaron por métodos fenotípicos y moleculares 39 cepas: 25 de Cd y 14 Ca, obtenidas 33 de bolsas periodontales y 6 de mucosa bucal de 15 pacientes VIH+ (8 con y 7 sin tratamiento). Se utilizó agar malta con yema de huevo, agar albúmina y agar sangre para demostrar la producción de F, P y H, respectivamente. Se inocularon por duplicado e incubaron a 37°C. Se midieron los diámetros de las colonias y los de hidrólisis alrededor de las mismas. Se observó mayor proporción de Ca en los pacientes sin tratamiento y mayor proporción de Cd en los con tratamiento; Chi2 p< 0.001. El 92,9% de las Ca estudiadas, fueron productoras de fosfolipasa. En tanto que ninguna Cd produjo la enzima. En cuanto a la producción de proteinasa se observa una alta producción tanto en las cepas de Ca, como en las Cd aisladas en los pacientes no tratados. Todas las cepas estudiadas produjeron hemolisina, observándose una diferencia estadísticamente significativa (p=0,04) en ambas especies a favor de la alta producción de la enzima en las cepas obtenidas de pacientes no tratados. Podemos concluir que en el biofilm subgingival, en los pacientes bajo TARGA, se aíslan mayor proporción de Candida dubliniensis las cuales expresan menos factores de virulencia.

Detection of Mycobacterium Tuberculosis DNA in Buccal Swab Samples from Children in Lima, Peru.

We examined Mycobacterium tuberculosis DNA detection from buccal swab samples collected from children in Lima, Peru. DNA was extracted and amplified via real-time polymerase chain reaction. Sensitivity was 21% (95% confidence interval [CI]: 7%-42%) in 24 culture-confirmed tuberculosis cases and 4.6% (95% CI: 1%-13%) in 65 clinically diagnosed unconfirmed cases. Sensitivity was highest for smear-positive tuberculosis. Specificity was 99% in the 199 controls (95% CI: 96%-100%).

Antifungal sensitivity and species of yeasts in oral mucosa of street mixed-breed dogs.

The aim of this research is to verify the yeast species isolated from oral mucosa in street mixed-breed dogs and to determine the antifungal profiles. After capturing and sedating the animals, oral mucosa samples were collected from fifty dogs and the materials were inoculated on Sabouraud dextrose agar with chloramphenicol. Forty-three yeast strains were isolated and identified trough the API-20C AUX method. Thirty-seven (86.1%) of the yeasts belonged to genus Candida, five (11.6%) to genus Trichosporon and only one strain (2.3%) to genus Malassezia. The sensitivity profiles to anifungals (amphotericin B, itraconanole, ketoconazole, fluconazole and variconazole) were determined through Etest® method. This study found resistance of some yeasts to amphotericin B and a good susceptibility to voriconazole and ketoconazole. Some of these antifungals are used in veterinary medical practice. This research is the first investigation on street mixed-breed dogs regarding yeast identifications and antifungals profiles.

Candida albicans Mrv8, is involved in epithelial damage and biofilm formation.

Candida albicans is the most common human fungal pathogen that can cause superficial and deep-seated infections in susceptible individuals. Despite its medical importance, the vast majority of C. albicans genes remain of unknown function. Here, we report a role for the lineage-specific gene, MRV8, in host pathogen interactions, mycelial microcolony maturation and biofilm formation. In silico analysis indicated that MRV8 encodes a four-pass transmembrane protein unique to the closely related pathogens C. albicans and Candida dubliniensis. Deletion of MRV8 did not affect C. albicans adherence to, or initial invasion into human oral epithelia, but inhibited mycelial development and strongly reduced epithelial damage. mrv8Δ/Δ cells exhibited a media-dependent defect in biofilm formation and mutant biofilm metabolic activity was enhanced by cyclosporin A. mrv8Δ/Δ biofilms were more tolerant to treatment with caspofungin, but not to fluconazole or amphotericin B. Co-stimulation with calcium chloride and calcofluor white rescued biofilm growth in the presence of caspofungin, and this rescue-effect was Mrv8-dependent. Together, our data demonstrate an important role for a lineage-specific gene (MRV8) in C. albicans biofilm formation, drug tolerance and host-pathogen interactions.

Biofilm Interactions of Candida albicans and Mitis Group Streptococci in a Titanium-Mucosal Interface Model.

Streptococci from the mitis group (represented mainly by Streptococcus mitis, Streptococcus oralis, Streptococcus sanguinis, and Streptococcus gordonii) form robust biofilms with Candida albicans in different experimental models. These microorganisms have been found in polymicrobial biofilms forming on titanium biomaterial surfaces in humans with peri-implant disease. The purpose of this work was to study mutualistic interactions in biofilms forming on titanium and their effect on the adjacent mucosa, using a relevant infection model. Single and mixed biofilms of C. albicans and each Streptococcus species were grown on titanium disks. Bacterial and fungal biovolume and biomass were quantified in these biofilms. Organotypic mucosal constructs were exposed to preformed titanium surface biofilms to test their effect on secretion of proinflammatory cytokines and cell damage. C. albicans promoted bacterial biofilms of all mitis Streptococcus species on titanium surfaces. This relationship was mutualistic since all bacterial species upregulated the efg1 hypha-associated gene in C. albicans Mixed biofilms caused increased tissue damage but did not increase proinflammatory cytokine responses compared to biofilms comprising Candida alone. Interestingly, spent culture medium from tissues exposed to titanium biofilms suppressed Candida growth on titanium surfaces.IMPORTANCE Our findings provide new insights into the cross-kingdom interaction between C. albicans and Streptococcus species representative of the mitis group. These microorganisms colonize titanium-based dental implant materials, but little is known about their ability to cause inflammation and damage of the adjacent mucosal tissues. Using an in vitro biomaterial-mucosal interface infection model, we showed that mixed biofilms of each species with C. albicans enhance tissue damage. One possible mechanism for this effect is the increased fungal hypha-associated virulence gene expression we observed in mixed biofilms with these species. Interestingly, we also found that the interaction of multispecies biofilms with organotypic mucosal surfaces led to the release of growth-suppressing mediators of Candida, which may represent a homeostatic defense mechanism of the oral mucosa against fungal overgrowth. Thus, our findings provide novel insights into biofilms on biomaterials that may play an important role in the pathogenesis of mucosal infections around titanium implants.

Cytokines Levels and Salivary Microbiome Play A Potential Role in Oral Lichen Planus Diagnosis.

Oral lichen planus (OLP) is a chronic Th1-mediated inflammatory mucocutaneous disease of the skin and oral mucosa that can have various clinical presentations. Lesions are usually bilateral and often painful. While cutaneous Lichen Planus (LP) lesions are self-limiting, the oral lesions are chronic and rarely remissive. The diagnosis of oral lichen planus (OLP) is often challenging, and confirmation by histopathological criterion is generally advised. The aim of our study was to identify the cytokines present in OLP-suggestive lesions and in non-specific inflammatory lesions (NSIL) used as controls. Moreover, assess cytokines protein levels and oral microbiota composition in whole saliva samples. Histopathological analysis, immunohistochemistry and gene expression were used as techniques to analyze the oral mucosal tissue samples. ELISA was conducted to analyze salivary cytokine levels and 16S rRNA sequencing was used to determine the salivary microbiome. As a result we observed larger number of infiltrated lymphocytes (p = 0.025), as well, more T CD4 lymphocytes in the epithelial tissue (p = 0.006) in OLP samples compared to NSIL. In addition, the OLP samples displayed more apoptotic cells compared to NSIL (p = 0.047). Regarding the cytokine analysis, IFN-γ and IL-33 were more expressed in OLP lesions than in NSIL samples (p < 0.001; p = 0.026). Furthermore, our results demonstrated higher levels of IFN-γ protein expression in the saliva of OLP group compared to controls (p = 0.0156). We also observed noted differences in the oral microbiota composition between OLP and NSIL saliva samples. In conclusion, OLP lesions presented larger numbers of apoptotic and inflammatory cells, higher levels of IFN-γ and IL-33 compared to NSIL, and these lesions also differ regarding oral microbiota composition. These results are consistent with the Th-1-mediated chronic inflammation nature of oral lichen planus investigated lesions and displayed unique features that could be used as a diagnostic tool.

Assessment of the oral microbiome in the development of recurrent oral aphthae in patients with gastrointestinal pathology

Chronic recurrent oral aphthae in residents living in an ecologically unfavourable region are characterized by a permanent course and prolonged recovery processes of regeneration of pathological elements of the oral mucosa. Using the microbiological method and modern test systems, it has been found that on the surface of aphthae an extremely diverse state of the oral microbiota is determined and its types are diverse. Trigger mechanisms have been determined. The role of representatives of various types of microorganisms - enterococci, staphylococci, streptococci, yeast-like fungi of the genus Candida (C. albicans) and obligate-anaerobes in the development of recurrent oral aphthae has been established. The data obtained can serve as an indication for the development of modern treatment and preventive measures regarding this category of patients.

The fecal, oral, and skin microbiota of children with Chagas disease treated with benznidazole.

BACKGROUND: Chagas disease is still prevalent in rural areas of South America. In endemic areas of Bolivia, school children are screened for the program of Chagas disease eradication of the Ministry of Health, and positive children are treated. Here, we compared the fecal, oral and skin microbiomes of children with or without Chagas disease, and before and after benznidazol treatment of infected children. METHODS: A total of 543 Bolivian children (5-14 years old) were tested for Chagas disease, and 20 positive children were treated with Benznidazole. Fecal samples and oral and skin swabs were obtained before and after treatment, together with samples from a group of 35 uninfected controls. The 16S rRNA genes were sequenced and analyzed using QIIME to determine Alpha diversity differences and community distances, and linear discriminant analyses to determine marker taxa by infection status or treatment. RESULTS: Twenty out of 543 children screened were seropositive for Chagas disease (3.7%) and were included in the study, together with 35 control children that were seronegative for the disease. Fecal samples, oral and skin swabs were taken at the beginning of the study and after the anti-protozoa therapy with Benznidazole to the chagasic children. Infected children had higher fecal Firmicutes (Streptococcus, Roseburia, Butyrivibrio, and Blautia), and lower Bacteroides and also showed some skin -but not oral- microbiota differences. Treatment eliminated the fecal microbiota differences from control children, increasing Dialister (class Clostridia) and members of the Enterobacteriaceae, and decreasing Prevotella and Coprococcus, with minor effects on the oral and skin bacterial diversity. CONCLUSIONS: The results of this study show differences in the fecal microbiota associated with Chagas disease in children, and also evidence that treatment normalizes fecal microbiota (makes it more similar to that in controls), but is associated with oral and skin microbiota differences from control children. Since microbiota impacts in children, it is important to determine the effect of drugs on the children microbiota, since dysbiosis could lead to physiological effects which might be avoidable with microbiota restoration interventions.

Paracoccidioidomycosis: characterization of subpopulations of macrophages and cytokines in human mucosal lesions.

Mucosal lesions of paracoccidioidomycosis (PCM) are frequently described and clinically important. Macrophages are classified as M1 or M2. M1 are proinflammatory and M2 are related to chronicity. Dectin-1 recognizes ß-glucan and plays an important role against fungal cells. The objective was to verify the presence of M1, M2, and dectin-1 and a possible correlation with Th1/Th2 cytokines in mucosal PCM lesions. In sum, 33 biopsies of oral PCM were submitted to histological and immunohistochemistry analysis, and positive cells were quantified. Eleven biopsies were characterized by compact granulomas (G1), 12 with loose granulomas (G2), and 10 with both kind of granulomas (G3). pSTAT-1 was equally increased in the three groups. G1 was characterized by an increased number of CD163+ macrophages. G2 presented similar number of arginase 1, iNOS, and CD163 expressing cells. G3 presented an increased number of cells expressing arginase 1 and CD163 over iNOS. G1 and G3 presented high number of cells expressing interferon (IFN)-γ; interleukin (IL) 5 was increased in G2 and G3; the expression of IL10 was similar among the three groups, and the expression of tumor necrosis factor (TNF)-α was higher in G3. G1 correlates to Th1 cytokines and pSTAT-1 and G2 correlates to Th2 cytokines. G3 presents both kinds of cytokines. We could not associate the expression of arginase-1, CD163, iNOS, and dectin-1 with the pattern of cytokines or kind of granuloma.

Detection of intracellular Helicobacter pylori in Candida. SPP from neonate oral swabs.

BACKGROUND: There is evidence of detection of Helicobacter pylori (H. pylori) in the stool of newborns and in the yeast that colonizes the oral cavity of this age group. However, there is a lack of research to confirm it. This study proposes to determine the existence of the bacteria at an early age, specifically in newborns. OBJECTIVE: To identify intracellular H. pylori in oral yeasts and to detect antigens of the bacteria in newborn stools. METHODOLOGY: Cross-sectional and descriptive study. Samples were obtained from infants (oral swab and meconium). Identification of yeast species was performed using the following techniques: CHROMagar Candida, Germinal Tube Test and API Candida Identification System, then the yeasts were observed by light microscopy and fluorescence. Detection of H. pylori antigen in meconium and PCR were performed to amplify specific genes of the bacterium (rRNA16S, cagA, vacA s1a, vacA s1b, vacA s2, vacA m1, vacA m2 and dupA). RESULTS: Intracellular H. pylori was detected in yeast of the species Candida glabrata (C. glabrata) isolated from an oral swab of a newborn. CONCLUSION: The results of this study evidenced the existence of intracellular H. pylori in newborns.

[Factors related to oral candidiasis in HIV children and adolescents, species characterization and antifungal susceptibility]. / Factores relacionados a candidiasis oral en niños y adolescentes con VIH, caracterización de especies y susceptibilidad antifúngica.

BACKGROUND: Factors associated with candidiasis and colonization in HIV-positive children and adolescents in developing countries are not well understood. AIM: To identify the factors associated with oral Candida colonization and candidiasis in institutionalized HIV-positive children and adolescents in Tijuana, México, as well as the response of the isolates to antifungals. MATERIALS AND METHODS: Sample of the oral mucosa of 30 HIV positive children and adolescents were obtained to isolate and identify Candida species by culture and metabolic profile. Antifungal drugs susceptibility was determined according to CLSI. Indicators of immunological and virologic failure were classified in accordance to WHO criteria. RESULTS: Six Candida species were identified from oral mucosa, 53% colonizers and 47% in candidiasis. Factors associated with candidiasis and oral colonization were viral load (p = 0,001), CD4+ counts (p = 0,002) and HAART regimen (p ≤ 0,014). The most prevalent species was C. glabrata (33%), but C. albicans (27%) was more resistant to fluconazole (p = 0,001). Itraconazol resistant species were identified in regimens that include an NNRTI (p = 0,041). CONCLUSION: HIV-positive children and adolescents living in an orphanage showed high prevalence of colonizing Candida spp. and resistance to antifungals, related to NNRTI.