Comparison of Enterococcus faecalis Biofilm Removal Efficiency among Bacteriophage PBEF129, Its Endolysin, and Cefotaxime.

Enterococcus faecalis is a Gram-positive pathogen which colonizes human intestinal surfaces, forming biofilms, and demonstrates a high resistance to many antibiotics. Especially, antibiotics are less effective for eradicating biofilms and better alternatives are needed. In this study, we have isolated and characterized a bacteriophage, PBEF129, infecting E. faecalis. PBEF129 infected a variety of strains of E. faecalis, including those exhibiting antibiotic resistance. Its genome is a linear double-stranded DNA, 144,230 base pairs in length. Its GC content is 35.9%. The closest genomic DNA sequence was found in Enterococcus phage vB_EfaM_Ef2.3, with a sequence identity of 99.06% over 95% query coverage. Furthermore, 75 open reading frames (ORFs) were functionally annotated and five tRNA-encoding genes were found. ORF 6 was annotated as a phage endolysin having an L-acetylmuramoyl-l-alanine amidase activity. We purified the enzyme as a recombinant protein and confirmed its enzymatic activity. The endolysin's host range was observed to be wider than its parent phage PBEF129. When applied to bacterial biofilm on the surface of in vitro cultured human intestinal cells, it demonstrated a removal efficacy of the same degree as cefotaxime, but much lower than its parent bacteriophage.

National Trends in the Repair of Isolated Superior Labral Tear from Anterior to Posterior in Korea.

BACKGROUND: The optimal treatment for superior labral tear from anterior to posterior (SLAP) lesions is controversial. Thus, we aimed to investigate the national surgical trends in isolated SLAP repair in Korea. METHODS: We analyzed a nationwide database from the Korean Health Insurance Review and Assessment Service from 2008 to 2017. We investigated the trends in SLAP repair by time, sex, age, and the type of health care institution. RESULTS: From 2008 to 2017, 27,850 isolated SLAP repairs were identified. Age-adjusted incidence rate of isolated SLAP repair increased by 692% from 1.07/100,000 in 2008 to 8.48/100,000 in 2012 (P = 0.005). However, the incidence rate declined significantly after 2012 (P = 0.032) and was 5.28/100,000 in 2017. Sex-specific incidence rate of isolated SLAP repair was 2.3 times higher in men than in women. The decline since 2012 was most evident in patients aged ≥ 40 years (P = 0.01); however, the incidence rates of isolated SLAP repair during the study period were similar between patients aged ≥ 40 years and those aged < 40 years. Moreover, hospitals with 30-100 beds had the greatest change in the number of isolated SLAP repair cases. CONCLUSION: In Korea, the incidence of isolated SLAP repair increased dramatically until 2012; since then, it has declined. Although the decrease in isolated SLAP repair later in the study was evident in those aged ≥ 40 years, the incidence rate was still relatively high in patients aged ≥ 40 years.

Complete genome sequence of a novel bacteriophage, ATCEA85, infecting Enterobacter aerogenes.

Enterobacter aerogenes is a member of the ESKAPE group of bacteria, and multi-drug-resistant strains are increasingly being found. In this study, a novel bacteriophage, ATCEA85, which infects E. aerogenes, has been isolated and characterized. ATCEA85 is seen to have a circularly permuted linear double-stranded DNA genome of 47,484 base pairs in length. The closest related phage found in the databases is the Klebsiella phage Kp3, which exhibits 77% identity over a 34% query coverage. The G+C content of ATCEA85 is 56.2%, and 15 putative open reading frames are functionally annotated.

Correction to: Complete genome sequence of a novel bacteriophage, PBKP05, infecting Klebsiella pneumoniae.

Unfortunately, the original article was published with incorrect accession number and the correct version is updated here.

Complete genome sequence of a novel bacteriophage, PBKP05, infecting Klebsiella pneumoniae.

An increasing number of Klebsiella pneumoniae isolates have been found to be multi-drug resistant. A novel bacteriophage, PBKP05, which infects K. pneumoniae, was isolated and characterized. It has a linear double-stranded DNA genome of 30,240 base pairs in length. Its G+C content is 53%, and 47 putative open reading frames are functionally annotated. This phage can be a candidate material for phage therapy.

3-D finite element analysis of the effects of post location and loading location on stress distribution in root canals of the mandibular 1st molar.

Objective The purpose of this study was to evaluate, by using finite element analysis, the influence of post location and occlusal loading location on the stress distribution pattern inside the root canals of the mandibular 1st molar. Material and Methods Three different 3-D models of the mandibular 1st molar were established: no post (NP) - a model of endodontic and prosthodontic treatments; mesiobuccal post (MP) - a model of endodontic and prosthodontic treatments with a post in the mesiobuccal canal; and distal post (DP) - a model of endodontic and prosthodontic treatments with a post in the distal canal. A vertical force of 300 N, perpendicular to the occlusal plane, was applied to one of five 1 mm2 areas on the occlusal surface; mesial marginal ridge, distal marginal ridge, mesiobuccal cusp, distobuccal cusp, and central fossa. Finite element analysis was used to calculate the equivalent von Mises stresses on each root canal. Results The DP model showed similar maximum stress values to the NP model, while the MP model showed markedly greater maximum stress values. The post procedure increased stress concentration inside the canals, although this was significantly affected by the site of the force. Conclusions In the mandibular 1st molar, the distal canal is the better place to insert the post than the mesiobuccal canal. However, if insertion into the mesiobuccal canal is unavoidable, there should be consideration on the occlusal contact, making central fossa and distal marginal ridge the main functioning areas.

3-D finite element analysis of the effects of post location and loading location on stress distribution in root canals of the mandibular 1st molar

Abstract Objective The purpose of this study was to evaluate, by using finite element analysis, the influence of post location and occlusal loading location on the stress distribution pattern inside the root canals of the mandibular 1st molar. Material and Methods Three different 3-D models of the mandibular 1st molar were established: no post (NP) - a model of endodontic and prosthodontic treatments; mesiobuccal post (MP) - a model of endodontic and prosthodontic treatments with a post in the mesiobuccal canal; and distal post (DP) - a model of endodontic and prosthodontic treatments with a post in the distal canal. A vertical force of 300 N, perpendicular to the occlusal plane, was applied to one of five 1 mm2 areas on the occlusal surface; mesial marginal ridge, distal marginal ridge, mesiobuccal cusp, distobuccal cusp, and central fossa. Finite element analysis was used to calculate the equivalent von Mises stresses on each root canal. Results The DP model showed similar maximum stress values to the NP model, while the MP model showed markedly greater maximum stress values. The post procedure increased stress concentration inside the canals, although this was significantly affected by the site of the force. Conclusions In the mandibular 1st molar, the distal canal is the better place to insert the post than the mesiobuccal canal. However, if insertion into the mesiobuccal canal is unavoidable, there should be consideration on the occlusal contact, making central fossa and distal marginal ridge the main functioning areas.

Long-Term Clinical Outcomes and Survivorship of Revision Total Knee Arthroplasty with Use of a Constrained Condylar Knee Prosthesis.

The purpose of this study was to determine long-term clinical and radiographic results. One hundred and ninety-four patients (228 knees) underwent revision TKA with use of a constrained condylar knee prosthesis. The mean duration of follow-up was 14.6 years (range, 11 to 16 years). The mean pre-revision Knee Society knee scores (43.5 points) and function scores (47.0 points), and Western Ontario and McMaster Universities Osteoarthritis index scores (88 points) were improved significantly (P=0.002) to 85.6, 68.5, and 25 points, respectively, at 14.6 years follow-up. Eighteen knees (8%) had re-revision. Four knees were re-revised for infection. Kaplan-Meier survivorship analysis revealed that the 16-year rate of survival of the components was 94.7% as the end point of loosening and 92% as the end point of revision.

Comparison of infection control rates and clinical outcomes in culture-positive and culture-negative infected total-knee arthroplasty.

BACKGROUND: To compare the outcomes of the culture positive and the culture negative infected TKA. METHODS: We determined the infection control rate in the 242 patients (140 patients with culture-positive and 102 patients with culture-negative diagnoses) with infected TKAs. RESULTS: The overall infection control rate was 90% in the culture positive group and 95% in the culture negative group. INTERPRETATION: The infection control rates and clinical outcomes of infected TKAs was not different between culture-positive and culture-negative groups.