Contamination of Low Frictional Elastomeric Ligatures by Streptococcus mutans: A Prospective RT-PCR and AFM Study

Objective: To compare Streptococcus mutans colonization between low-friction elastomeric ligatures and to correlate microbial colonization levels with the surface roughness status.Methods: The study included 160 premolars of 10 patients. During the study period, which consisted of 4 sessions each lasting 4 weeks, the ligature types Slide™ Low-Friction Ligature (Leone, Firenze, Italy), Tough-O Energy™ (Rocky Mountain Orthodontics, Denver, USA), and Sili Ties™ (Dentsply Sirona, Surrey KT13 0NY, UK), and steel ligatures (American Orthodontics, Sheboygan, USA) as a control, were fixed to the premolar teeth by clockwise rotation among the jaw quadrants. The plaque index (PI) and gingival index (GI) were obtained before bonding (T0), 6 weeks after bonding (T1), and subsequently every 4 weeks (T2, T3, T4). Presence of S. mutans was analyzed by real-time polymerase chain reaction at T1, T2, T3, T4. Surface roughness was evaluated with Atomic Force Microscopy (AFM) before ligation (Ra0) and after (Ra1) ligation. The paired t-test, ANOVA, repeated measures of ANOVA, and the Kruskal–Wallis test were used for the statistical analysis.Results: S. mutans colonization was significantly higher on the Slide group (P .05).Conclusion:S. mutans colonization showed variations in low-friction elastomeric ligatures independent of surface roughness. Ringshaped low-friction elastomeric ligatures were not different from the steel ligature in terms of S. mutans colonization

The Coincidence of Newly Diagnosed Type 1 Diabetes Mellitus with IgM Antibody Positivity to Enteroviruses and Respiratory Tract Viruses

Objective. Viruses trigger and promote islet cell destruction and cause type 1 diabetes mellitus (T1DM). However, the existence of a cause-and-effect relationship is under debate. The aim of this study is to investigate the sero-epidemiological and molecular evidence on enteroviruses and respiratory viruses in patients with newly diagnosed T1DM during the cold season. Design. Forty children newly diagnosed with T1DM and 30 healthy children who presented to the clinic over the course of a year were included in the study. The IgM antibodies against enteroviruses and respiratory viruses were studied using the indirect immunofluorescence assay (IFA) test, and no CBV4-specific RNA was detected in the children. The onset times of T1DM were classified into fall-winter and spring-summer seasons and separated into cold, moderate, or warm months in terms of temperature. Results. The percentages of viral IgM antibodies against most common viruses were detected in the patients as follows: influenza B (IVB) (70%), echovirus 7 (ECHO7) (45%), parainfluenza virus 4 (PIV4) (40%), coxsackievirus A7 (CAV7) (27.5%), and H3N2 (22.5%). Compared with the control group, the above viruses had a significant association with T1DM (p≤0.001, p≤0.001, p=0.035, p=0.003, and p=0.023, resp.). CBV4-specific RNA was not detected in any serum. A total of 75% and 95% patients were diagnosed with T1DM in the fall-winter seasons and cold-moderate months, respectively. Conclusion. Our study demonstrates the significant association between T1DM and the presence of IgM antibodies against IVB, ECHO7, PIV4, CAV7, and H3N2, and the majority of newly diagnosed T1DM appeared in the fall-winter season. It suggests that enteroviruses and respiratory viruses, in addition to seasonal variation, could play a role in the etiopathogenesis and clinical onset of T1DM

Investigating the presence of fungal agents in febrile neutropenic patients using different microbiological, serological, and molecular methods

This study aimed to investigate fungal agents in febrile neutropenic patients with hematological malignancies. Direct microscopy and cultures were performed on clinical samples collected from febrile neutropenic episodes. The galactomannan (GM) antigen was tested using enzyme-linked immunosorbent assays, and Aspergillus fumigatus and Candida albicans deoxyribonucleic acid (DNA) assessed using real-time polymerase chain reaction (PCR) in consecutive serum samples. Of the 199 episodes investigated, 1.5% were classified as definite invasive aspergillosis (IA), 4.0% as IA with high probability, and 4.0% as IA with low probability. Additionally, candidaemia was detected in eight episodes (4.1%). The GM antigen was found negative for 86.4% of episodes, as one positive for 7.0% of episodes, as two or more consecutive positives for 5.5% of episodes, and as positive in any two serum samples in 1.0% of episodes. While no C. albicans DNA was detected in 98.5% of 199 episodes, one positive result was obtained in 1.0% of episodes, and two or more consecutive positives in 0.5% of episodes. A. fumigatus PCR results were found negative in 81.9% of episodes, as one positive in 16.1% of episodes, as positive in any two serum samples in 1.0% of episodes, and consecutively positive in 1.0% of episodes. GM antigen tests were found consecutively positive in all three patients diagnosed as having definite IA. These findings indicate that conventional, serological, and molecular methods should be used in combination to detect fungal agents in febrile neutropenic patients

Frequency of azole resistance in clinical and environmental strains of Aspergillus fumigatus in Turkey: A multicentre study

Objectives: Aspergillus fumigatus causes several diseases in humans and azole resistance in A. fumigatus strains is an important issue. The aim of this multicentre epidemiological study was to investigate the prevalence of azole resistance in clinical and environmental A. fumigatus isolates in Turkey. Methods: Twenty-one centres participated in this study from 1 May 2018 to 1 October 2019. One participant from each centre was asked to collect environmental and clinical A. fumigatus isolates. Azole resistance was screened for using EUCAST agar screening methodology (EUCAST E.DEF 10.1) and was confirmed by the EUCAST E.DEF 9.3 reference microdilution method. Isolates with a phenotypic resistance pattern were sequenced for the cyp51A gene and microsatellite genotyping was used to determine the genetic relationships between the resistant strains. Results: In total, resistance was found in 1.3% of the strains that were isolated from environmental samples and 3.3% of the strains that were isolated from clinical samples. Mutations in the cyp51A gene were detected in 9 (47.4%) of the 19 azole-resistant isolates, all of which were found to be TR34/L98H mutations. Microsatellite genotyping clearly differentiated the strains with the TR34/L98H mutation in the cyp51A gene from the strains with no mutation in this gene. Conclusions: The rate of observed azole resistance of A. fumigatus isolates was low in this study, but the fact that more than half of the examined strains had the wild-Type cyp51A gene supports the idea that other mechanisms of resistance are gradually increasing. © 2022 The Author(s) 2022