Hyperbaric oxygen therapy for the placement of dental implants in irradiated patients: systematic review and meta-analysis.

This study was a systematic review with meta-analysis to evaluate the influence of hyperbaric oxygen therapy (HBOT) on the survival of dental implants placed in patients who had had radiotherapy for cancer of the head and neck. A systematic literature search was conducted using the PubMed/Medline, Science Direct, Embase and the Cochrane Library, between January 1985 and July 2018. The study observed the PRISMA (Preferred Reporting Items for Systematic review and Meta-Analysis) declaration and norms, and the systematic review was duly recorded in the PROSPERO (International prospective register of systematic reviews) database. Inclusion and exclusion criteria were applied, and all articles were selected on the basis of PICO questions. The process of eligibility and quality evaluation yielded three studies for statistical analysis. Based on the survival rates, there was no evidence that the risk of an implant failing was different between the patients who received HBOT and those who did not. Moreover, the risk of an implant failing did not depend on the anatomical site. HBOT exerted no beneficial influence on the survival rates of implants placed in irradiated patients, and the risk of an implant failing did not depend on its location.

Acetylcholinesterase affinity-based screening assay on Lippia gracilis Schauer extracts.

The use of affinity-based protein assay produced by covalently linking acetylcholinesterase to magnetic beads, followed by chemical characterization of the selective binders using Liquid Chromatography with tandem High-Resolution Mass Spectrometry (LC-HRMS) is herein described for profiling crude aqueous natural product extracts. The fishing assay was first modulated using galanthamine as a reference ligand and then, the assay condition was adjusted for the aqueous leaves extracts obtained from Lippia gracilis Schauer (genotype 201) that was used as the natural combinatory library. From the experiments, a selective binder has been undisclosed with an accurate mass of 449.1131 m/z and identified as eriodictyol 2'-O-glucoside or eriodictyol 3'-O-glucoside. The selectivity of the binding assay was demonstrated, as much as, that erydictiol 7-O-glucoside was not fished, although it was present in the crude aqueous extract. The binding assay platform exhibited high specificity and did not require any sample pretreatment, making it appropriate for profiling binders at natural libraries.

Long-term success of dental implants in patients with head and neck cancer after radiation therapy.

The purpose of this study was to analyze the long-term success and factors potentially influencing the success of dental implants placed in patients with head and neck cancer who underwent radiation therapy with a minimum total dose of 50Gy during the years 1995-2010. Thirty-five patients (169 dental implants) were included in this study. Data on demographic characteristics, tumour type, radiation therapy, implant sites, implant dimensions, and hyperbaric oxygen therapy (HBOT) were obtained from the medical records and analyzed. Implant survival was estimated using Kaplan-Meier survival curves. Seventy-nine dental implants were placed in the maxilla and 90 in the mandible. The mean follow-up after implant installation was 7.4 years (range 0.3-14.7 years). The overall 5-year survival rate for all implants was 92.9%. Sex (P<0.001) and the mode of radiation therapy delivery (P=0.005) had a statistically significant influence on implant survival. Age, time of implantation after irradiation, implant brand and dimensions, and HBOT had no statistically significant influence on implant survival. Osseointegrated dental implants can be used successfully in the oral rehabilitation of patients with head and neck cancer with a history of radiation therapy. Risk factors such as sex and the mode of radiation therapy delivery can affect implant survival.

Survival of vancomycin-intermediate Staphylococcus aureus on hospital surfaces.

BACKGROUND: Contaminated surfaces play an important role in the transmission of certain pathogens that are responsible for healthcare-associated infections. Although previous studies have shown that meticillin-resistant Staphylococcus aureus (MRSA) can survive on dry surfaces at room temperature, no published data regarding vancomycin-intermediate S. aureus (VISA) are available to date. AIM: To compare the survival time on different types of surfaces, cell-surface hydrophobicity, adherence to abiotic surfaces and biofilm formation of meticillin-susceptible S. aureus (MSSA), MRSA and VISA. METHODS: Survival of the S. aureus strains was tested on latex, cotton fabric, vinyl flooring and formica. Cell-surface hydrophobicity was determined using the hydrocarbon interaction affinity method. Adhesion to abiotic surfaces was tested on granite, latex (gloves), glass, vinyl flooring and formica. Biofilm formation was evaluated at 6, 12, 24 and 48 h. FINDINGS: All of the samples survived on the vinyl flooring and formica for at least 40 days. VISA survived on both surfaces for more than 45 days. All of the strains were highly hydrophobic. VISA adhered to latex, vinyl flooring and formica. Biofilm formation increased for all of the tested strains within 6-24 h. CONCLUSION: VISA present high survival, adherence and cell-surface hydrophobicity. Therefore, as the treatment of patients with VISA is a significant challenge for clinicians, greater care with cleaning and disinfection of different types of surfaces in healthcare facilities is recommended because these may become important reservoirs of multi-resistant pathogens.

Antimicrobial efficacy of alcohol-based hand gels with a 30-s application.

AIMS: The objective of this study was to assess the antimicrobial efficacy of alcohol-based hand gels according to European Norm 1500 (EN 1500). METHODS AND RESULTS: We assessed the antimicrobial efficacy of 12 alcohol-based hand gels produced in Brazil, containing 70% w/w or v/v ethyl alcohol as the active ingredient, according to EN 1500, with a 30-s application. In addition, 70% w/w ethyl alcohol and three alcohol-based hand rubs commonly used in Europe and effective according to EN 1500 were also tested. Eight of 12 (67%) alcohol-based hand gels produced in Brazil failed by EN 1500. In contrast, 70% w/w ethyl alcohol and European alcohol-based hand rubs were approved by EN 1500. CONCLUSIONS: In this study, the majority of Brazilian alcohol-based hand gels showed limited efficacy on hand hygiene within 30 s. SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of this study may be used as an important argument to motivate Brazilian manufacturers to improve the antimicrobial efficacy of alcohol-based hand gels, because it is prudent to suppose that alcohol-based hand gels can be recommended for use in healthcare settings only if they show antimicrobial activity at least similar to that of alcohol-based liquid preparations, including the traditional 70% w/w ethyl alcohol.

Evolution of antimicrobial resistance of Acinetobacter baumannii in a university hospital.

AIMS: To investigate the susceptibility pattern and the molecular epidemiology of Acinetobacter baumannii isolates in two periods (1994-1996 and 2004-2007) in Londrina University Hospital. METHODS AND RESULTS: Antimicrobial susceptibility of 150 A. baumannii isolates was assessed by disc diffusion and agar dilution methods. Genetic similarity amongst the isolates was evaluated by ERIC-PCR. Resistance of A. baumannii to carbapenems increased from 2% (1994-1996) to 73% (2004-2007). Thirty-eight clones were detected. CONCLUSIONS: The results of the study suggest that the high prevalence of carbapenem resistance amongst Acinetobacter baumannii organisms in this institution is not caused by the spread of a predominant clone. SIGNIFICANCE AND IMPACT OF THE STUDY: This work reinforces the importance monitoring antimicrobial susceptibility rates.

Effect of MTGase, dietary fiber and UV irradiation upon heat-induced Gilthead seabream (Sparus aurata) gels.

The effects of microbial transglutaminase (MTGase, 0.5%, w/w), dietary fiber (konjac flour, Kjc, 1. 0%, w/w) and ultraviolet irradiation, UV (254 nm, 3300 µW/cm(2) and 40 min), on heat-induced gels from gilthead seabream mince (Sparus aurata) were studied. MTGase addition improved texture, force at rupture increased from 44.3±18.1 to 131.9 ± 56.7 N, and increased pH and water-holding capacity. Moreover, MTGase reduced the elastic modulus E(1) and darkened the gels; protein solubility declined, meaning greater protein aggregation, according to electropherograms. Evidence was found that disulfide bonding has a role in textural improvement by MTGase. Kjc increased the hardness from 15.1±3.1 to 20.6 ± 4.7 N, the elastic modulus and WHC. Kjc itself and not its effect upon proteins may explain the hardening effect. However, gels containing Kjc were less deformable and Kjc reduced the extractable protein in the various selective bond media. UV did not present advantages as a gelation-promoting technology. MTGase and Kjc were texturally advantageous, although without synergies for gel strength: it fell from 56.9±7.1 to 24.6±5.9 N mm as a result of adding Kjc to gels containing MTGase. Nevertheless, the hardening effect of Kjc and MTGase combined surpassed the sum of the individual effects, thereby indicating the existence of a mutual reinforcement of the hardness through MTGase and konjac. Additionally, this study showed that gilthead seabream may be used to produce good quality (concerning texture, color and WHC) heat-induced gels.

Fibroma de células gigantes: una presentación inusual en un niño de 2 años de edad / Giant cell fibroma: an unusual presentation in a child of 2 years old

El objetivo de este artículo es relatar un caso clínico de fibroma de células gigantes en un niño de 2 años de edad. Asimismo, presentar una revisión de literatura sobre esta entidad y discutir sobre posibles factores involucrados a su etiología

The aim of this paper is to report a clinical case of giant cell fibroma in a 2-years-old child. Also present a review of literature from this entity and discuss possible factors involved in its etiology

O objetivo deste artigo é relatar um caso clínico de fibroma de células gigantes em uma criança de 2 anos de idade. Além disso, apresentar uma revisão de literatura sobre esta entidade e discutir sobre possíveis fatores associados a sua etiologia

In vitro evaluation of the antimicrobial activity of meropenem in combination with polymyxin B and gatifloxacin against Pseudomonas aeruginosa and Acinetobacter baumannii.

The antimicrobial activity of meropenem combined with either polymyxin B or gatifloxacin was evaluated by the checkerboard method against Pseudomonas aeruginosa (10 strains) and Acinetobacter baumannii (10 strains). In addition, the triple combination of polymyxin B, gatifloxacin, and meropenem was also studied as well as the polymyxin B and gatifloxacin combination. A partial synergism interaction between meropenem and polymyxin B was observed for 80% of the A. baumannii strains. In contrast, this combination showed an indifferent effect for 80% of the P. aeruginosa strains tested. The combination of meropenem and gatifloxacin showed synergism only for two strains of A. baumannii, and partial synergism and additive effect for seven strains and indifference for four strains of both species. For the strains of P. aeruginosa, the double combination of polymyxin B and gatifloxacin and the triple combination of meropenem, polymyxin B and gatifloxacin were indifferent for the majority of the strains tested, that is, 90 and 80% respectively.

Survival of tubercle bacilli in heat-fixed and stained sputum smears.

We used a slide culture technique to detect tubercle bacilli surviving in sputum smears (n=46) after conventional heat fixation and Ziehl-Neelsen staining. In all heat-fixed sputum smears, tubercle bacilli survived after time 0 (n=22), 24 h (n=7), 48 h (n=7), 72 h (n=4), and seven days (n=6). None of the stained sputum smears showed growth on slide cultures. Viable tubercle bacilli remaining in heat-fixed sputum smears for at least seven days may present an infection risk to laboratory staff. Thus, sputum smears should be stained immediately by the Ziehl-Neelsen method or stored in a safe container to avoid transmission of tuberculosis.

Effectiveness of hand-cleansing agents for removing methicillin-resistant Staphylococcus aureus from contaminated hands.

OBJECTIVE: The effectiveness of hand-cleansing agents in removing a hospital strain of methicillin-resistant Staphylococcus aureus from artificially contaminated hands of five volunteers was studied. DESIGN: The products used were plain liquid soap, ethyl alcohol 70% (by weight), 10% povidone-iodine liquid soap (PVP-I), and chlorhexidine gluconate (4%) detergent. The experiments were performed using a Latin square statistical design, with two 5x4 randomized blocks. The removal rates of S aureus cells from contaminated fingertips were estimated by analysis of variance, the response variable being the log10 reduction factor (RF), ie, log10 of the initial counts minus log10 of the final counts. In the first and second blocks, the fingertips of the volunteers were contaminated in mean with 3.76 log10 colony-forming units ([CFU] light-contamination hand) and 6.82 log10 CFU (heavy-contamination hand), respectively. RESULTS: In the first block, there were significant differences between treatments (P<.05). The 10% PVP-I (RF, 3.76) and 70% ethyl alcohol (RF, 3.51) had significantly higher removal rates than plain liquid soap (RF, 1.96) and 4% chlorhexidine (RF, 1.91). In the second block, 10% PVP-I (RF, 4.39) and 70% ethyl alcohol (RF, 3.27) also were significantly more effective than plain liquid soap (RF, 1.77) and 4% chlorhexidine (RF, 1.37; P<.05). Plain liquid soap was significantly more effective than chlorhexidine (4%) detergent. CONCLUSIONS: The results suggest that 10% PVP-I and 70% ethyl alcohol may be the most effective hand-cleansing agents for removing methicillin-resistant S aureus strain from either lightly or heavily contaminated hands.

Effectiveness of hand-cleansing agents for removing Acinetobacter baumannii strain from contaminated hands.

BACKGROUND: The effectiveness of hand-cleansing agents (plain liquid soap, 70% ethyl alcohol, 10% povidone-iodine, and 4% chlorhexidine gluconate) for removing a hospital strain of Acinetobacter baumannii from artificially contaminated hands of 5 volunteers was studied. METHODS: The experiments were performed by using a Latin square statistical design, with two 5 x 4 randomized blocks, and the results were estimated by ANOVA. In the first and second blocks, the fingertips of the volunteers were contaminated with approximately 10(3) colony-forming units (light contamination hand) and 10(6) colony-forming units (heavy contamination hand), respectively. RESULTS: In the first block, all products tested were effective, almost completely removing the microbial population of A baumannii artificially applied to the hands. In the second block, the use of hand-cleansing agents resulted in 91.36% (4% chlorhexidine), 92.33% (liquid soap), 98.49% (10% povidone-iodine), and 98.93% (70% ethyl alcohol) reduction in counts of A baumannii cells applied to the fingertips. The ethyl alcohol and povidone-iodine had significantly higher removal rates than plain soap and chlorhexidine (P <.05). CONCLUSIONS: These results suggest that 70% ethyl alcohol and 10% povidone-iodine may be the most effective hand-cleansing agents for removing A baumannii strain from heavily contaminated hands (10(6) colony-forming units/fingertip).

Rapid decontamination of gutta-percha cones with sodium hypochlorite.

Gutta-percha cones are now widely used to fill root canals. Because they cannot be sterilized by conventional autoclaving or in a hot-air oven, gutta-percha cones require rapid chairside decontamination before use to maintain the aseptic chain, an essential factor in successful endodontic therapy. The purpose of this study was to compare the effectiveness of different concentrations of sodium hypochlorite (0.25% to 4%) in sterilizing gutta-percha cones artificially contaminated with Staphylococcus aureus and Escherichia coli strains, and Bacillus subtilis spores. After 1 min of treatment, the solutions tested showed bactericidal and sporicidal effects at concentrations of 0.25% and 1%, respectively. At a concentration of 0.25%, the solutions tested were effective in destroying spores after 5 min of exposure. Based on this study, treatment of the cones for 1 min with 1% sodium hypochlorite (Milton's solution) or for 5 min with Dakin's liquid (0.5% sodium hypochlorite) is recommended.

Rapid sterilization of gutta-percha cones with glutaraldehyde.

Five commercially available liquid glutaraldehyde preparations (Glutaron II, Cidex 28, Glutalabor, Banicide, and Anti-G-Plus) were compared for effectiveness in sterilizing gutta-percha cones artificially contaminated with Bacillus subtilis ATCC 6633 spores. Sporicidal activity differed for the various brands of cones, but after 15 min all glutaraldehyde solutions were effective in eliminating the spores. However, three solutions (Cidex 28, Banicide, and Anti-G-Plus) showed sporicidal activity within a shorter time (10 min). All glutaraldehyde solutions tested may be used in endodontic practice for rapid decontamination of gutta-percha cones, thus contributing to the maintenance of the aseptic chain, an essential factor for successful root canal treatment.

Simplified technique for detection of significant bacteriuria by microscopic examination of urine.

A comparative study of microscopic examination of 10 microl (simplified loop technique) and 50 microl (traditional drop technique) of uncentrifuged Gram-stained urine specimens for detection of significant bacteriuria was carried out. The results demonstrated that the 10-microl loop technique can be used as an alternative to the 50-microl drop technique for presumptive diagnosis of urinary-tract infection in bacteriological practice, with the advantages of greater rapidity and ease of performance.