Purine and pyrimidine synthesis differently affect the strength of the inoculum effect for aminoglycoside and ß-lactam antibiotics.

The inoculum effect has been observed for nearly all antibiotics and bacterial species. However, explanations accounting for its occurrence and strength are lacking. We previously found that growth productivity, which captures the relationship between [ATP] and growth, can account for the strength of the inoculum effect for bactericidal antibiotics. However, the molecular pathway(s) underlying this relationship, and therefore determining the inoculum effect, remain undiscovered. We show that nucleotide synthesis can determine the relationship between [ATP] and growth, and thus the strength of inoculum effect in an antibiotic class-dependent manner. Specifically, and separate from activity through the tricarboxylic acid cycle, we find that transcriptional activity of genes involved in purine and pyrimidine synthesis can predict the strength of the inoculum effect for ß-lactam and aminoglycosides antibiotics, respectively. Our work highlights the antibiotic class-specific effect of purine and pyrimidine synthesis on the severity of the inoculum effect and paves the way for intervention strategies to reduce the inoculum effect in the clinic.

A comprehensive comparison and evaluation of surgical techniques for anterior shoulder instability: a Bayesian network meta-analysis.

BACKGROUND: Anterior shoulder instability is a common clinical problem; however, conflicting evidence exists regarding optimal treatment algorithms. We perform a comparative analysis of stabilization techniques used for recurrent anterior shoulder instability to identify the one associated with the lowest rate of recurrent instability. We additionally explore how glenoid bone loss and osseus lesions affect recurrence rates. METHODS: PubMed, MEDLINE, Embase, and Cochrane databases were searched for clinical studies comparing surgical techniques for anterior shoulder instability. Two team members independently assessed all potential studies for eligibility and extracted data. Each included study underwent a risk of bias assessment using the Cochrane risk of bias summary tool. The primary outcome of interest was the rate of recurrent instability, which underwent a Bayesian network meta-analysis. Additional analyses were performed relating to the degree of glenoid bone loss and the presence of osseous lesions. RESULTS: Of 2699 studies screened, 52 studies with 4209 patients were included. Patients who underwent open Latarjet demonstrated the overall lowest rate of recurrent instability [log odds ratio (LOR) 1.93], whereas patients who underwent arthroscopic Bankart repair demonstrated the highest (LOR 2.87). When glenoid bone loss was 10% to 20%, open Latarjet had significantly lower recurrent instability (P = .0016) compared to arthroscopic Bankart repair. When glenoid bone loss increased from 0%-10% to 10%-20%, arthroscopic Bankart repair had a significantly increased rate of recurrence (P = .021). In the presence of an engaging Hill-Sachs lesion, both open Latarjet (P = .01) and arthroscopic Bankart with remplissage (P = .029) had significantly reduced recurrence rates compared to arthroscopic Bankart repair. Finally, regardless of procedure, the presence of a Hill-Sachs or bony Bankart lesion was associated with an increased risk of recurrent instability (r = 0.44, P = .0003, and r = 0.40, P = .006, respectively). CONCLUSION: The open Latarjet has the overall lowest recurrent instability and significantly lower compared to arthroscopic Bankart repair in the setting of increasing glenoid bone loss. Bone loss between 0% and 10% results in similar outcomes across all procedures.

Do Patients Accurately Recall Their Preoperative Symptoms After Elective Orthopedic Procedures?

Patient-reported outcome measures are a frequent tool used to assess orthopedic surgical outcomes. However, recall bias is a potential limitation of these tools when used retrospectively, as they rely on patients to accurately recall their preoperative symptoms. A database search of Cochrane Library, PubMed, Medline Ovid, and Scopus until May 2021 was completed in duplicate by two reviewers. Studies considered eligible for inclusion were those which reported on patient recall bias associated with orthopedic surgery. The primary outcome of interest investigated was the accuracy of patient recollection of preoperative health status. Any factors that were identified as affecting patient recall were secondary outcomes of interest. Of the 4,065 studies initially screened, 20 studies with 3,454 patients were included in the final analysis. Overall, there were 2,371 (69%) knee and hip patients, 422 (12%) shoulder patients, 370 (11%) spine patients, 208 (6%) other upper extremity patients, and 83 (2%) foot and ankle patients. Out of the eight studies that evaluated patient recall within three months postoperatively, seven studies concluded that patient recall is accurate. Out of the 13 studies that evaluated patient recall beyond three months postoperatively, nine studies concluded that patient recall is inaccurate. The accuracy of patient recall of preoperative symptoms after elective orthopedic procedures is not reliable beyond three months postoperatively.

Arthroscopy Association of Canada Position Statement on Exercise for Knee Osteoarthritis: A Systematic Review of Guidelines.

BACKGROUND: Exercise is widely regarded to improve pain and function in patients with knee osteoarthritis (OA) through building supportive muscle mass, facilitating weight loss, and through the other beneficial effects associated with it. PURPOSE: To explore literature that presents clinical guidelines for the use of exercise in the treatment of knee OA to inform an evidence-based position statement for the Arthroscopy Association of Canada. STUDY DESIGN: Position statement. METHODS: PubMed, MEDLINE, Embase, and Cochrane databases were searched for guidelines commenting on the role of exercise for knee OA. The search was limited to guidelines published in the last 10 years. Articles were screened for relevance, focusing on recently published research with clinical guidelines. Inclusion criteria involved all articles providing clinical guidelines for exercise and knee OA. RESULTS: Eight guidelines were identified. All eight recommended exercise as an important component of treatment for knee OA, with 6/8 strongly recommending it. CONCLUSION: Exercise is an effective and important component of the non-pharmacological management of knee OA. The Arthroscopy Association of Canada strongly recommends the use of exercise in the management of knee OA.