Antibacterial activity of Thymus vulgaris (thyme) essential oil against strains of Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus saprophyticus isolated from meat product.

Meat products represent an important component of the human diet and are a good source of nutrients. Food-borne microorganisms are the main pathogens that cause human diseases as a result of food consumption, especially products of animal origin. The objective of the present research was to verify the antibacterial activity of the essential oil of Thymus vulgaris against strains of Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus saprophyticus isolated from meat products. For this, the analyses of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were performed in microdilution plates. The association of the product with antimicrobials was also studied using disk diffusion. And the anti-adherent activity, which was determined in the presence of sucrose, in glass tubes. Thyme oil showed a strong inhibitory activity against K. pneumoniae, P. aeruginosa and S. saprophyticus, with the MIC values ranging from 64 to 512 µg/mL, and bactericidal effect for most strains, with MBC values ranging from 256 to 1,024 µg/mL. T. vulgaris oil exhibited varied interactions in association with the antimicrobials, with synergistic (41.67%), indifferent (50%) and antagonistic (8.33%) effects. Regarding the anti-adherent activity, the test product was effective in inhibiting the adherence of all bacterial strains under study. Therefore, thyme oil presents itself as an antibacterial and anti-adherent agent against K. pneumoniae, P. aeruginosa and S. saprophyticus, being a natural product that can represent an interesting alternative in the efforts to combat foodborne diseases.

Systemic administration of probiotics reduces the severity of apical periodontitis.

AIM: To evaluate the effect of systemic administration of probiotics on the severity of apical periodontitis (AP). METHODOLOGY: Twenty-four male Wistar rats were used. AP was induced in the maxillary left/right first molars. The animals were arranged into groups: Control, Lactobacillus rhamnosus, and Lactobacillus acidophilus. Probiotics were administered orally for gavage (109 colony-forming units diluted in 5 mL of water for 30 days) during the development of AP. After 30 days, cardiac puncture was performed to analyse the complete blood count. Moreover, microbiological analysis of the root canal contents and saliva was performed. Then, the animals were euthanized and the jaw removed for histopathological and IL-10, IL-1ß and IL-6 immunolabeling analyses. After the Shapiro-Wilk test of normality, the Kruskal-Wallis followed by Dunn's test was performed for nonparametric data, and analysis of variance followed by the Tukey test was performed for parametric data (P < 0.05). RESULTS: No significance difference was observed in the blood profiles and in the counts of microorganisms from the saliva samples among the groups (P > 0.05). Total microorganism counts in the root canal, the inflammatory infiltrate and the immunostaining for IL-1ß and IL-6 in AP were significantly lower in the probiotic groups when compared with the control group (P < 0.05). IL-10 was significantly more immunolabled in the probiotic groups than in the control group (P < 0.05). CONCLUSION: Supplementation with probiotics (Lactobacillus rhamnosus and Lactobacillus acidophilus) had a significant effect on the severity of apical periodontitis in rats, demonstrating the anti-inflammatory effect of probiotics on the development of apical periodontitis.

Osteoradionecrosis prevalence and associated factors: A ten years retrospective study.

BACKGROUND: Osteoradionecrosis (ORN) is one of the most serious complications of head and neck radiotherapy and is considered a public health problem worldwide. This study aims to determine the prevalence and associated factors of ORN in patients undergoing radiotherapy for head and neck malignancy. MATERIAL AND METHODS: A cross-sectional retrospective study was conducted, in which all medical records of patients undergoing head and neck radiation in the period between 2006 to 2015 (10 years) were examined. Clinical and demographic data were extracted. Multivariate Poisson regression analysis with robust variance was employed to access the relationship between ORN and independent variables (p < 0.05; 95% CI). RESULTS: The sample comprised 413 medical records of patients undergoing radiotherapy. The prevalence of ORN was 9.7 %. Most participants were males (78.2%). The mean age of subjects was 55 years (± 14 years). The mandible was the main site of occurrence of ORN (85.0%). The following variables were associated with ORN : presence of oral mucositis (PR = 3.03; 95% CI: 1.30-7.03), history of smoking (PR = 0.23; 95% CI: 0.07-0.74), number of teeth removed before radiotherapy (PR = 1.06; 95% CI: 1.01-1.11) and visit to the dentist before radiation (PR = 0.08; 95% CI: 1.02-1.11). CONCLUSIONS: The prevalence of ORN was low and was associated with the presence of oral mucositis and the number of removed teeth before radiation. Visiting the dentist before radiotherapy and stop-ping smoking were protective factors for ORN.

Mesodesma mactroides Gill Cells Exposed to Copper: Does Hyposmotic Saline Increase Cytotoxicity or Cellular Defenses?

Gill cells of filter feeding mollusks have cellular defense mechanisms, such as multixenobiotic resistance (MXR), that allow them to extrude possible contaminants. To analyze the cytotoxicity and cellular defenses of gills in the clam Mesodesma mactroides, gill cells were exposed to copper in both iso- and hyposmotic solutions. Analysis of MXR activity by fluorescence microscopy showed that hyposmotic saline activated defenses, whereas the presence of copper in isosmotic solution inhibited the activation of defenses. Cell viability was decreased in cells exposed to copper in isosmotic saline, but not in cells exposed to hyposmotic saline. We conclude that when cells cannot defend themselves due to decreased MXR, cell death occurs. In addition, gill cells under hyposmotic conditions have a greater capacity for defense and a lower rate of cellular mortality than when they are maintained under isosmotic conditions.

Relationship between galactomannan structure and physicochemical properties of films produced thereof.

In this work five sources of galactomannans, Adenanthera pavonina, Cyamopsis tetragonolobus, Caesalpinia pulcherrima, Ceratonia siliqua and Sophora japonica, presenting mannose/galactose ratios of 1.3, 1.7, 2.9, 3.4 and 5.6, respectively, were used to produce galactomannan-based films. These films were characterized in terms of: water vapour, oxygen and carbon dioxide permeabilities (WVP, O 2 P and CO 2 P); moisture content, water solubility, contact angle, elongation-at-break (EB), tensile strength (TS) and glass transition temperature (T g ). Results showed that films properties vary according to the galactomannan source (different galactose distribution) and their mannose/galactose ratio. Water affinity of mannan and galactose chains and the intermolecular interactions of mannose backbone should also be considered being factors that affect films' properties. This work has shown that knowing mannose/galactose ratio of galactomannans is possible to foresee galactomannan-based edible films properties.

A multiplex panel of short-amplicon insertion-deletion DNA polymorphisms for forensic analysis.

We have previously developed a panel of 40 insertion-deletion (INDEL) human DNA polymorphisms that was proven to ad-equately cover the span of global human genetic diversity. The panel was found to have very low matching probabilities with respect to both the global and Brazilian populations. To optimize the panel for application with degraded DNA samples, which are commonly encountered in fo-rensic analysis, we have significantly reduced the amplicon size of the INDELs and developed a new multiplex panel. The panel has an ampli-con size ranging from 50 to 153 base pairs, with a mean of 93 base pairs. It could be amplified by polymerase chain reaction in two multiplex re-actions, which were then combined for electrophoretic separation and identification of the individual products in the ABI3130 four-color DNA analyzer. The results of the new panel were fully validated.

In vitro antimicrobial activity and biocompatibility of propolis containing nanohydroxyapatite.

The high number of biomaterial associated infections demands new strategies to prevent this problem. In this study the suitability of nanohydroxyapatite (nanoHA)-based surfaces containing two Brazilian extracts of propolis (green and red ones) to prevent bacterial growth and biofilm formation, as well as its non-cytotoxic nature, was investigated. Optical density, colony forming units and MTT reduction assay were used to assess the materials' antibacterial activity against planktonic and sessile growth of Staphylococcus aureus. NanoHA matrix was able to absorb both types of propolis and the obtained results revealed the antibacterial effectiveness of the novel materials expressed as the reduction of bacterial growth and biofilm formation ability. Additionally, cell culture tests showed the growth of fibroblasts with high metabolic activity and without membrane damage. Therefore, these nanoHA-based surfaces containing natural products deriving from bees may be a promising bioactive biomaterial to be further studied with the aim of application to orthopaedic or dental devices.

Assessment of the hemodynamic profile in periodontal tissues of diabetic subjects with periodontitis by optical spectroscopy.

BACKGROUND AND OBJECTIVE: The influence of diabetes mellitus (DM) on the hemodynamics of periodontal tissues has not been assessed previously. The primary objective of this study was to validate optical spectroscopy as a periodontal diagnostic tool for subjects with type 2 DM and chronic periodontitis. MATERIAL AND METHODS: Using a portable optical near-infrared spectrometer, optical spectra were obtained from healthy (n = 127), gingivitis (n = 115), and periodontitis (n = 109) sites of 65 subjects with type 2 DM and chronic periodontitis. Healthy (n = 65) sites of 15 nondiabetic subjects without periodontitis were used as controls. A modified Beer-Lambert unmixing model that incorporates a nonparametric scattering-loss function was used to determine the relative contribution of deoxygenated hemoglobin and oxygenated hemoglobin (HbO2 ) to the overall spectrum. The balance between tissue oxygen delivery and oxygen utilization in periodontal tissues was assessed. RESULTS: In diabetic subjects, tissue oxygen saturation and HbO2 concentration were significantly decreased in the periodontitis sites (p < 0.01) compared with the healthy and gingivitis sites. Furthermore, tissue oxygenation in healthy sites of control subjects was significantly higher than that in sites of diabetic subjects (p < 0.01). CONCLUSION: In summary, the results of this study suggest that optical spectroscopy can monitor the hemodynamic profile in diabetic subjects with chronic periodontitis. Furthermore, healthy sites of diabetic subjects presented lower tissue oxygenation than did those of nondiabetic subjects.

Full-mouth scaling and root planing in type 2 diabetic subjects: one-year microbiological outcomes.

BACKGROUND: This study evaluated the microbiological effects of full-mouth (FM) and partial-mouth (PM) scaling and root planing (SRP) in type 2 diabetic subjects with chronic periodontitis (ChP), up to 12 months. METHODS: Thirty-four type 2 diabetic subjects with ChP received either FMSRP (n = 17), in two sessions within two consecutive days, or PMSRP (n = 17) in four sessions within 21 days. Six subgingival biofilm samples per subject were analysed by checkerboard DNA-DNA hybridization for 40 bacterial species at baseline, 3 and 12 months. RESULTS: Both therapies significantly reduced the levels of the red complex species up to 12 months (p < 0.05). The levels of three putative pathogens from the orange complex were significantly reduced in the FMSRP group, whereas a single orange complex species was significantly decreased in the PMSRP group (p < 0.05). Furthermore, the proportions of the host-compatible Actinomyces species were significantly increased in both groups at 3 and 12 months. No significant differences were observed between groups for the counts and proportions of the individual species and the proportions of microbial complexes at any time point (p > 0.05). CONCLUSIONS: There were no differences in the bacterial species evaluated after FMSRP and PMSRP in the treatment of type 2 diabetic subjects with ChP, up to 12 months.

Electroretinography in dogs using a fiber electrode prototype.

We compared two electroretinography (ERG) electrodes in dogs using ERG standards of the International Society for Clinical Electrophysiology of Vision (ISCEV). Ten healthy Yorkshire terrier dogs (mean age, 2.80 ± 1.42 years; 6 females) weighing 5.20 ± 1.56 kg were evaluated using an ERG system for veterinary use. Dark- and light-adapted ERG responses were recorded using an ERG-Jet electrode and a fiber electrode prototype. The examinations were performed during 2 visits, 3 weeks apart. Both electrodes (ERG-Jet or fiber prototype) were used on each animal and the first eye to be recorded (OD × OS) was selected randomly. Three weeks later the examination was repeated on the same animal switching the type of electrode to be used that day and the first eye to be examined. The magnitude and waveform quality obtained with the two electrode types were similar for all ERG responses. ERG amplitudes and implicit times obtained from dogs using the fiber electrode prototype were comparable to those obtained with the ERG-Jet electrode for rod, maximal rod-cone summed, cone, and 30-Hz flicker responses. The fiber electrode prototype is a low-cost device, available as an alternative instrument for clinical veterinary ERG recording for retinal function assessment.

Electroretinography in dogs using a fiber electrode prototype

We compared two electroretinography (ERG) electrodes in dogs using ERG standards of the International Society for Clinical Electrophysiology of Vision (ISCEV). Ten healthy Yorkshire terrier dogs (mean age, 2.80 ± 1.42 years; 6 females) weighing 5.20 ± 1.56 kg were evaluated using an ERG system for veterinary use. Dark- and light-adapted ERG responses were recorded using an ERG-Jet electrode and a fiber electrode prototype. The examinations were performed during 2 visits, 3 weeks apart. Both electrodes (ERG-Jet or fiber prototype) were used on each animal and the first eye to be recorded (OD × OS) was selected randomly. Three weeks later the examination was repeated on the same animal switching the type of electrode to be used that day and the first eye to be examined. The magnitude and waveform quality obtained with the two electrode types were similar for all ERG responses. ERG amplitudes and implicit times obtained from dogs using the fiber electrode prototype were comparable to those obtained with the ERG-Jet electrode for rod, maximal rod-cone summed, cone, and 30-Hz flicker responses. The fiber electrode prototype is a low-cost device, available as an alternative instrument for clinical veterinary ERG recording for retinal function assessment.

Appendicular Lean Soft Tissue: Development and Cross-Validation of Predictive Models for Older Men and Women.

BACKGROUND: Sarcopenia may explain, in a large proportion, physical disability, falls and fractures, especially in aged elderly. However, a diagnosis in an operationally systematic, simple and low cost way is extremely important, particularly for home-based, epidemiological studies. OBJECTIVE: The purpose of this study was to develop and validate predictive equations of appendicular lean soft tissue (ALST) in elderly older than 80 years. DESIGN AND SETTINGS: A validation study was performed in 106 elderly (men and women) aged 80 years and older. MEASUREMENTS: Body weight, height, circumference (arm, midcalf, hip and waist) and triceps skinfold were measured in the elderly. ALST were measured using as the reference method dual-energy X-ray absorptiometry (DXA). RESULTS: Two models were predicted. The first model (ALST, in kg = 0.074*height + 0.277*weight - 0.144*triceps skinfold - 0.103*waist circumference + 1.831*gender -0.966), which considered all possible variables in stepwise multiple regression, presented better statistical performance (r2 = 0.82; SEE = 1.67 kg), compared to the second model (ALST, in kg = 0.138*height + 0.103*weight + 3.061*gender - 12.489), a more practical equation, due to a lesser quantity of predictive variables (r2 = 0.75; SEE = 1.94 kg). Both models were validated, however, it was verified trend (p<0.05) for overestimation of predicted ALST. CONCLUSION: In summary, two models for predicting ALST in men and women with age ≥ 80 years were developed and cross-validated. Model 1, with a greater number of predictive variables, presented a better accuracy than did the model with only three variables (height, weight, and gender). Validation studies are needed to test the usefulness of both models in other populations.

Subgingival biodiversity in subjects with uncontrolled type-2 diabetes and chronic periodontitis.

BACKGROUND AND OBJECTIVE: There is a bidirectional relationship between periodontal disease and type-2 diabetes mellitus (DM). Inflammatory mediators may negatively affect glycemic control, and increased glucose levels and resultant glycation end-products may alter the host response against bacterial infection. However, no agreement has been reached regarding the effect of DM on periodontal subgingival microbiota. Therefore, the purpose of the present study was to compare the subgingival biodiversity in deep periodontal pockets of subjects with chronic periodontitis and either uncontrolled type-2 diabetes or no diabetes using 16S rRNA gene cloning and sequencing. MATERIAL AND METHODS: Twelve subjects with uncontrolled type-2 diabetes (glycated hemoglobin > 8%) and eleven nondiabetic subjects presenting severe and generalized chronic periodontitis were selected. Subgingival biofilm from periodontal pockets > 5 mm were assessed using the 16S rRNA gene cloning and sequencing technique. RESULTS: Significant differences were observed in subgingival microbiota between diabetic and nondiabetic subjects. Diabetic subjects presented higher percentages of total clones of TM7, Aggregatibacter, Neisseria, Gemella, Eikenella, Selenomonas, Actinomyces, Capnocytophaga, Fusobacterium, Veillonella and Streptococcus genera, and lower percentages of Porphyromonas, Filifactor, Eubacterium, Synergistetes, Tannerella and Treponema genera than nondiabetic individuals (p < 0.05). Moreover, some phylotypes, such as Fusobacterium nucleatum, Veillonella parvula, V. dispar and Eikenella corrodens were detected significantly more often in diabetic subjects than in nondiabetic subjects (p < 0.05). CONCLUSION: Subjects with uncontrolled type-2 diabetes and chronic periodontitis presented significant dissimilarities in subgingival biodiversity compared with nondiabetic subjects.

A preliminary study on the FAM5C expression in generalized chronic periodontitis.

OBJECTIVE: The Family with sequence similarity 5 member C (FAM5C) has been suggested to contribute in aggressive periodontitis. However, there is no data regarding its role in chronic periodontitis. The aim of this study was to evaluate the FAM5C expression in chronic periodontitis and to study association of FAM5C with key immunoinflammatory markers. MATERIAL AND METHODS: Gingival biopsies were harvested from periodontally healthy subjects (n = 10) and chronic periodontitis subjects (n = 15). The levels of mRNA of FAM5C, interleukin (IL)-17, IL-6, IL-23, IL-10, IL-4, interferon-c, toll-like receptor (TLR)-2, TLR-4, osteoprotegerin (OPG), receptor activator of NF-κB ligand (RANKL), tumor necrosis factor (TNF)-a, transforming growth factor-b, transcription factor forkhead box p3, and transcription factor orphan nuclear receptor C2 were evaluated by real-time polymerase chain reaction. RESULTS: FAM5C mRNA levels were not different between periodontally healthy and diseased tissues (P > 0.05). Gene expressions of IL-17, TNF-a, OPG, RANKL, TLR-2, and TLR-4 were higher in periodontitis, when compared to periodontally healthy sites (P < 0.05), while no differences between groups were observed for the other genes evaluated (P > 0.05). There were no correlations between the gene expression of FAM5C and the other immunoinflammatory markers (P > 0.05). CONCLUSION: Within the limits of this study, it seems that FAM5C expression does not contribute to chronic periodontitis.

Partial- and full-mouth scaling and root planing in type 2 diabetic subjects: a 12-mo follow-up of clinical parameters and levels of cytokines and osteoclastogenesis-related factors.

BACKGROUND AND OBJECTIVE: The aim of this study was to evaluate the effects of full-mouth scaling and root planing (FMSRP) and partial-mouth scaling and root planing (PMSRP), up to 12 mo after treatment, on clinical parameters, and levels of cytokines and osteoclastogenesis-related factors in type 2 diabetic subjects with chronic periodontitis. MATERIAL AND METHODS: Thirty-four subjects received FMSRP (n = 17) or PMSRP (n = 17) within 24 h or in multiple sessions, respectively. Clinical parameters and local levels of tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin (IL)-17, IL-23, IL-4, receptor activator of NF-ß ligand and osteoprotegerin were assessed at baseline, and 3, 6 and 12 mo after therapies. RESULTS: Clinical parameters improved after both therapies (p < 0.05), and no between-group differences were observed at any time-point (p > 0.05). Overall, there were no considerable differences in the local levels of the biomarkers studied between groups (p > 0.05). The IL-23 concentration and total amount of IFN-γ increased in the FMSRP group and decreased in the PMSRP group from baseline to 3 mo and from baseline to 6 mo, respectively (p < 0.05). CONCLUSION: Both PMSRP and FMSRP promoted benefits in clinical parameters and showed a similar modulation of cytokines and osteoclastogenesis-related factors at 12 mo in type 2 diabetic subjects.

Contributions of mature granule cells to structural plasticity in temporal lobe epilepsy.

During the development of epilepsy in adult animals, newly generated granule cells integrate abnormally into the hippocampus. These new cells migrate to ectopic locations in the hilus, develop aberrant basal dendrites, contribute to mossy fiber sprouting, and exhibit changes in apical dendrite structure and dendritic spine number. Mature granule cells do not appear to exhibit migration defects, basal dendrites, and mossy fiber sprouting, but whether they exhibit apical dendrite abnormalities or spine changes is not known. To address these questions, we examined the apical dendritic structure of bromodeoxyuridine (Brdu)-birthdated, green fluorescent protein (GFP)-expressing granule cells born 2 months before pilocarpine-induced status epilepticus. In contrast to immature granule cells, exposing mature granule cells to status epilepticus did not significantly disrupt the branching structure of their apical dendrites. Mature granule cells did, however, exhibit significant reductions in spine density and spine number relative to age-matched cells from control animals. These data demonstrate that while mature granule cells are resistant to developing the gross structural abnormalities exhibited by younger granule cells, they show similar plastic rearrangement of their dendritic spines.

Possible involvement of IL-21 and IL-10 on salivary IgA levels in chronic periodontitis subjects.

Specific cytokines and the costimulatory protein CD40 play role in inducing immunoglobulin (Ig)A production by B cells in the humoral immune response. However, to date, the role of these mediators was not investigated in chronic periodontitis. Therefore, the aim of this study was to assess the local levels of interleukin (IL)-21, IL-21 receptor (IL-21R), IL-4, IL-10 and CD40 ligand (CD40L) on chronic periodontitis subjects and their relationship with the salivary levels of IgA. Gingival biopsies and un-stimulated saliva were collected from chronic periodontitis (n = 15) and periodontally healthy (n = 15) subjects. The mRNA levels of IL-4, IL-10, IL-21, IL-21R, CD40L in the gingival biopsies were evaluated by quantitative real-time polymerase chain reaction. The salivary levels of IgA and the levels of IL-4 and IL-10 in the gingival biopsies were analyzed by ELISA. The mean levels of IgA were significantly higher in the chronic periodontitis compared to periodontally healthy group (P < 0.05). The mRNA levels for IL-21 was higher (P < 0.05) in the chronic periodontitis when compared to the healthy group. However, the expression of IL-21R and CD40L did not differ between groups. The IL-10 was significantly elevated at mRNA and protein levels in chronic periodontitis when compared to periodontally healthy group (P < 0.05). Conversely, the mRNA levels as well as the protein amount of IL-4 were significantly lower (P < 0.05) in chronic periodontitis than healthy ones. In conclusion, the upregulation of IL-21 and IL-10 and downregulation of IL-4 in periodontitis tissues may be collectively involved in the increased levels of salivary IgA in chronic periodontitis subjects.

Assessment of the antimicrobial activity of Casearia sylvestris extract against oral pathogenic microorganisms

An ethanolic extract of leaves from the tree Casearia sylvestris, known as guaçatonga in Brazil, was tested for in vitro activity against oral pathogenic bacteria and fungi. The results showed susceptibility of all the microorganisms tested. This study suggests a potential use of ethanolic extract of C. sylvestris as a novel treatment of oral infectious conditions, such as denture stomatitis, periodontitis and dental caries.

Oral candidiasis treatment with Brazilian ethanol propolis extract.

The Brazilian commercial ethanol propolis extract, also formulated to ensure physical and chemical stability, was found to inhibit oral candidiasis in 12 denture-bearing patients with prosthesis stomatitis candidiasis association.

Surface effects and desorption of tetracycline supramolecular complex on bovine dentine.

The aim of this in vitro study was to evaluate the antimicrobial activity, the substantivity, and surface effects of the inclusion compound tetracycline: beta-cyclodextrin on bovine roots. The antimicrobial activity was assessed by dentine slabs which had been immersed in the inclusion complex in concentrations 8.0%, 4.0%, 2.0%, 1.0%, 0.5% and 0.25% for 5min compared to a control of tetracycline hydrochloride. Each slab was tested in a broth of overnight culture of Actinobacillus actinomycetemcomitans (Y4-FDC). The inclusion complex significantly inhibited the A. actinomycetemcomitans (p<0.01) verified at concentrations from 1.0% to 8.0%. The substantivity of tetracycline was evaluated by the measure of desorption from the slabs previously immersed in solution samples and removed at 24h intervals. The tetracycline encapsulated in beta-cyclodextrin showed a flow rate near to zero order in comparison to free tetracycline. The surface morphology determined by SEM showed a more homogeneous and integrated layer with the complex compared to the effect of free tetracycline. We concluded that the root surfaces treated with tetracycline: beta-cyclodextrin release lower concentrations of active drug over 5 days at inhibitory concentrations against A. actinomycetemcomitans with enhanced disponibility in comparison to tetracycline.