Establishing Normal Variances and Expectations for Quadriceps Limb Symmetry Index Benchmarks Based on Time from Surgery After Anterior Cruciate Ligament Reconstruction.

The anticipated timeline for muscle strength as well as return to running and sports are some of the most common inquiries by patients undergoing anterior cruciate ligament reconstruction. Despite the popularity of this procedure, the answers to these inquiries are not well described in the literature. The purpose of this study was to evaluate the range of quadriceps strength percentage and function benchmarks at various points after anterior cruciate ligament reconstruction surgery based on sex, age, and graft. Design: Observational Cohort Study. Methods: Patients who underwent anterior cruciate ligament reconstruction (ACLR) were evaluated at various points after their surgery with handheld dynamometer assessments. Additional hop and balance testing was performed and patients were evaluated for clearance for running and sport via a physical therapist directed functional movement assessment (FMA). The progression of quadriceps symmetry throughout the postoperative period was examined with multi-level models, estimates of time to reach 70%, 80%, and 90% quadriceps symmetry were obtained from the fitted model. Results: A total of 164 patients were evaluated. Patients either received bone-tendon-bone (BTB) autograft (n=118) or BTB allograft (n=46) for their ACL graft. Average age was 31.1 years-of-age (SD: 13.6). Males undergoing ACLR using BTB autograft (n=53) were able to achieve 80% quadriceps symmetry earlier than females (n=65) (5.7 months vs 7.1 months), were cleared to return to run sooner (5.6 months vs 6.8 months) and passed an FMA exam earlier (8.5 months vs 10 months). Males undergoing ACLR with allograft (n=13) were able to achieve 80% quadriceps symmetry earlier than females (n=33) (3.9 months vs 5.4 months) and were cleared to run sooner (4.5 months vs 5.8 months). Conclusion: Patients undergoing BTB autograft obtain 80% quadriceps symmetry at an average of 5.7 months for males and 7.1 months for females. Individuals under the age of 25 obtain their quadriceps symmetry faster and are cleared to return to running faster than individuals over 25. Male sex is associated with decreased amount of time to obtain clearance for running and for full activity. Male sex is associated with decreased amount of time to regain quadriceps symmetry however this was not significant. Level of Evidence: 4 (Case series).

Increasing Diversity of Patients in Radiation Oncology Clinical Trials.

Radiation oncology clinical trials lack full representation of the ethnic and racial diversity present in the general United States and in the cancer patient population. There are low rates of both recruitment and enrollment of individuals from underrepresented ethnic and racial backgrounds, especially Black and Hispanic patients, people with disabilities, and patients from underrepresented sexual and gender groups. Even if approached for enrollment, barriers such as mistrust in medical research stemming from historical abuse and contemporary biased systems, low socioeconomic status, and lack of awareness prohibit historically marginalized populations from participating in clinical trials. In this review, we reflect on these specific barriers and detail approaches to increase diversity of the patient population in radiation oncology clinical trials to better reflect the communities we serve. We hope that implementation of these approaches will increase the diversity of clinical trials patient populations in not only radiation oncology but also other medical specialties.

Induction of T Cell Responses by Vaccination of a Streptococcus pneumoniae Whole-Cell Vaccine.

The induction of T cell responses by vaccination is important for protection against infection. We have previously shown that immunization with a killed Streptococcus pneumoniae whole-cell vaccine (SPWCV) by either intranasal immunization or subcutaneous immunization induced T cell responses to SPWCV. Protection against colonization by S. pneumoniae is dependent on CD4+ IL-17A production induced by immunization. Here, we present detailed protocols for preparation of SPWCV, immunization of mice, and assay for T cell responses in blood and splenocytes in immunized mice.

Characterization of a Novel Iron Acquisition Activity That Coordinates the Iron Response with Population Density under Iron-Replete Conditions in Bacillus subtilis.

Iron is an essential micronutrient required for the viability of many organisms. Under oxidizing conditions, ferric iron is highly insoluble (∼10-9 to 10-18 M), yet bacteria typically require ∼10-6 M for survival. To overcome this disparity, many bacteria have adopted the use of extracellular iron-chelating siderophores coupled with specific iron-siderophore uptake systems. In the case of Bacillus subtilis, undomesticated strains produce the siderophore bacillibactin. However, many laboratory strains, e.g., JH642, have lost the ability to produce bacillibactin during the process of domestication. In this work, we identified a novel iron acquisition activity from strain JH642 that accumulates in the growth medium and coordinates the iron response with population density. The molecule(s) responsible for this activity was named elemental Fe(II/III) (Efe) acquisition factor because efeUOB (ywbLMN) is required for its activity. Unlike most iron uptake molecules, including siderophores and iron reductases, Efe acquisition factor is present under iron-replete conditions and is regulated independently of Fur repressor. Restoring bacillibactin production in strain JH642 inhibits the activity of Efe acquisition factor, presumably by sequestering available iron. A similar iron acquisition activity is produced from a mutant of Escherichia coli unable to synthesize the siderophore enterobactin. Given the conservation of efeUOB and its regulation by catecholic siderophores in B. subtilis and E. coli, we speculate that Efe acquisition factor is utilized by many bacteria, serves as an alternative to Fur-mediated iron acquisition systems, and provides cells with biologically available iron that would normally be inaccessible during aerobic growth under iron-replete conditions. IMPORTANCE: Iron is an essential micronutrient required for a variety of biological processes, yet ferric iron is highly insoluble during aerobic growth. In this work, we identified a novel iron acquisition activity that coordinates the iron response with population density in laboratory strains of Bacillus subtilis We named the molecule(s) responsible for this activity elemental Fe(II/III) (Efe) acquisition factor after the efeUOB (ywbLMN) operon required for its uptake into cells. Unlike most iron uptake systems, Efe acquisition factor is present under iron-replete conditions and is regulated independently of Fur, the master regulator of the iron response. We speculate that Efe acquisition factor is highly conserved among bacteria and serves as a backup to Fur-mediated iron acquisition systems.