Pseudomonas aeruginosa (P. aeruginosa) possesses a plethora of virulence determinants, including the production of biofilm, pigments, exotoxins, proteases, flagella, and secretion systems. The aim of our present study was to establish the relationship between biofilm-forming capacity, the expression of some important virulence factors, and the multidrug-resistant (MDR) phenotype in P. aeruginosa. A total of three hundred and two (n = 302) isolates were included in this study. Antimicrobial susceptibility testing and phenotypic detection of resistance determinants were carried out; based on these results, isolates were grouped into distinct resistotypes and multiple antibiotic resistance (MAR) indices were calculated. The capacity of isolates to produce biofilm was assessed using a crystal violet microtiter-plate based method. Motility (swimming, swarming, and twitching) and pigment-production (pyoverdine and pyocyanin) were also measured. Pearson correlation coefficients (r) were calculated to determine for antimicrobial resistance, biofilm-formation, and expression of other virulence factors. Resistance rates were the highest for ceftazidime (56.95%; n = 172), levofloxacin (54.97%; n = 166), and ciprofloxacin (54.64%; n = 159), while lowest for colistin (1.66%; n = 5); 44.04% (n = 133) of isolates were classified as MDR. 19.87% (n = 60), 20.86% (n = 63) and 59.27% (n = 179) were classified as weak, moderate, and strong biofilm producers, respectively. With the exception of pyocyanin production (0.371 ± 0.193 vs. non-MDR: 0.319 ± 0.191; p = 0.018), MDR and non-MDR isolates did not show significant differences in expression of virulence factors. Additionally, no relevant correlations were seen between the rate of biofilm formation, pigment production, or motility. Data on interplay between the presence and mechanisms of drug resistance with those of biofilm formation and virulence is crucial to address chronic bacterial infections and to provide strategies for their management.

About 30% of male infertility cases are idiopathic. Previous studies reported a positive correlation between deep periodontal pockets and sperm sub-motility, which suggests that periodontitis might have a role in idiopathic semen abnormality pathospermia. We evaluated correlations between periodontal infection parameters and the results of sperm analysis of men with idiopathic infertility. In this observational study, semen quality and periodontal status were analyzed for 95 otherwise healthy men attending an andrology unit for sperm analysis. Half the men in the sperm pathology and normozoospermia groups (50.8% and 50%, respectively) had poor periodontal status. Among the 95 participants, 38% had oligozoospermia, 28% had asthenozoospermia, 16% had cryptozoospermia, and 15% were classified as normozoospermic. Sperm pathology category was not associated with frequency of deep periodontal pockets or calculus. Bleeding on probing was significantly lower among men with asthenozoospermia than among those with normozoospermia. Poor periodontal status was not associated with any sperm pathology category or parameter. In contrast with previous findings, the present results indicate that pathospermia and poor semen quality are not associated with periodontal infection in men with idiopathic infertility. (J Oral Sci 58, 247-253, 2016)

Bacteria can enhance their survival by attaching to inanimate surfaces or tissues, and presenting as multicellular communities encased in a protective extracellular matrix called biofilm. There has been pronounced interest in assessing the relationship between the antibiotic resistant phenotype and biofilm-production in clinically-relevant pathogens. The aim of the present paper was to provide additional experimental results on the topic, testing the biofilm-forming capacity of Escherichia coli isolates using in vitro methods in the context of their antibiotic resistance in the form of a laboratory case study, in addition to provide a comprehensive review of the subject. In our case study, a total of two hundred and fifty (n = 250) E. coli isolates, originating from either clean-catch urine samples (n = 125) or invasive samples (n = 125) were included. The colony morphology of isolates were recorded after 24h, while antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method. Biofilm-formation of the isolates was assessed with the crystal violet tube-adherence method. Altogether 57 isolates (22.8%) isolates were multidrug resistant (MDR), 89 isolates (35.6%) produced large colonies (>3 mm), mucoid variant colonies were produced in 131 cases (52.4%), and 108 (43.2%) were positive for biofilm formation. Biofilm-producers were less common among isolates resistant to third-generation cephalosporins and trimethoprim-sulfamethoxazole (P = 0.043 and P = 0.023, respectively). Biofilms facilitate a protective growth strategy in bacteria, ensuring safety against environmental stressors, components of the immune system and noxious chemical agents. Being an integral part of bacterial physiology, biofilm-formation is interdependent with the expression of other virulence factors (especially adhesins) and quorum sensing signal molecules. More research is required to allow for the full understanding of the interplay between the MDR phenotype and biofilm-production, which will facilitate the development of novel therapeutic strategies.

ABO blood group antigen (ABGA) secretion into the saliva and other body fluids is a well-known phenomenon, and there is evidence to suggest a link between secretor status and the appearance of caries. It has been proposed that secretion of these antigens into the saliva might be caries-preventive, however, this proposition is still a matter of debate. Our aim was to examine the relationship between caries experience and secretor status in a group of Hungarian children and adolescents in a cross-sectional study. Altogether 130 children and adolescents participated in the study (aged 6-18 years). Participants were divided into two groups according to dentition (i.e. mixed and permanent). ABGA were determined from saliva. The DMF-T and dmf-t (decayed, missing, and filled) indices were calculated, as well as the oral health hygiene index-simplified plaque index. Association of these indices with secretor status was examined. In mixed dentition, the mean dmf-t values were significantly lower in the secretor group (2.1 ± 0.52 SEM), as compared to the nonsecretor group (3.8 ± 0.93 SEM; p < 0.05, Mann-Whitney U test). The finding that children of mixed dentition are apparently better protected against caries suggests that the assumed protective effect might be associated with deciduous teeth, but given the general paucity of knowledge about this topic, further research is indicated.

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The formation of a protective biofilm by Pseudomonas aeruginosa (PA) is one of the hallmarks of their survival both in vivo and in harsh environmental conditions, thus, biofilm-eradication has relevance from therapeutic perspectives and for infection control. The aim of our study was to investigate the possible relationship between antibiotic resistance, biofilm-forming capacity and virulence factors in n = 166 PA isolates of environmental origin. Antimicrobial susceptibility testing and the phenotypic detection of resistance determinants were carried out using standard protocols. The biofilm-forming capacity of PA was tested using a standardized crystal violet microtiter plate-based method. Motility (swimming, swarming, and twitching) and siderophore production of the isolates were also assessed. Resistance rates were highest for ciprofloxacin (46.98%), levofloxacin (45.18%), ceftazidime (31.92%) and cefepime (30.12%); 19.28% of isolates met the criteria to be classified as multidrug-resistant (MDR). Efflux pump overexpression, AmpC overexpression, and modified Hodge-test positivity were noted in 28.31%, 18.07% and 3.61%, respectively. 22.89% of isolates were weak/non-biofilm producers, while 27.71% and 49.40% were moderate and strong biofilm producers, respectively. Based on MDR status of the isolates, no significant differences in biofilm-production were shown among environmental PA (non-MDR OD570 [mean ± SD]: 0.416 ± 0.167 vs. MDR OD570: 0.399 ± 0.192; p > 0.05). No significant association was observed between either motility types in the context of drug resistance or biofilm-forming capacity (p > 0.05). 83.13% of isolates tested were positive for siderophore production. The importance of PA as a pathogen in chronic and healthcare-associated infections has been described extensively, while there is increasing awareness of PA as an environmental agent in agriculture and aquaculture. Additional studies in this field would be an important undertaking to understand the interrelated nature of biofilm production and antimicrobial resistance, as these insights may become relevant bases for developing novel therapeutics and eradication strategies against PA.

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Work-related exposures affecting oral health are important factors of morbidity and decreased quality of life, which may emerge from numerous physical, chemical, or mental occupational exposures. Copper (Cu) is an important trace element, however, it may also cause allergies, depose and accumulate in the body, leading to acute and chronic toxicity. In the present report, we describe a rare phenomenon found during the examination of two professional brass players, after incidentally noting an artefact during magnetic resonance imaging (MRI) scans, which were performed to monitor bone healing after bone augmentation procedures in an unrelated clinical study. During a detailed workup of patient characteristics, data on medical history, lifestyle, professional habits related to playing the instrument, and oral health status were collected. Overall, both patients presented with similar histories, and the differences from the context of this study were not relevant; however, both brass players were using an uncoated Cu mouthpiece for over 15 years. Based on the imaging findings (a shadow in the area of the lips on the MRI images) and the organoleptic evaluation of the lips and mucosa of the individuals (temporary faint green discoloration), it is most likely that the brass players were affected by oxidized Cu accumulation in the lip. In contrast to several professions, musicians are usually not required by law to attend obligatory occupational health check-ups, which may facilitate the occurrence of such exposures in musicians. Clinicians should be on the lookout for brass players involved in the profession for a long time, who may have used the mouthpieces for an extended period of time, in addition to musicians affected by Wilson’s disease. In patients affected by this phenomenon, diagnostics of oral cancer and prosthodontic procedures may be cumbersome, due to the detrimental impact on the utility of MRI imaging from artefact-formation and scattering.