Insights into the enigma of oral streptococci in carcinogenesis.

SUMMARYThe genus Streptococcus consists of a taxonomically diverse group of Gram-positive bacteria that have earned significant scientific interest due to their physiological and pathogenic characteristics. Within the genus Streptococcus, viridans group streptococci (VGS) play a significant role in the oral ecosystem, constituting approximately 80% of the oral biofilm. Their primary role as pioneering colonizers in the oral cavity with multifaceted interactions like adherence, metabolic signaling, and quorum sensing contributes significantly to the complex dynamics of the oral biofilm, thus shaping oral health and disease outcomes. Perturbations in oral streptococci composition drive oral dysbiosis and therefore impact host-pathogen interactions, resulting in oral inflammation and representing VGS as an opportunistic pathogen. The association of oral streptococci in tumors across distant organs, spanning the esophagus, stomach, pancreas, and colon, illuminates a potential association between oral streptococci, inflammation, and tumorigenesis. This finding emphasizes the need for further investigations into the role of oral streptococci in mucosal homeostasis and their involvement in carcinogenesis. Hence, here, we review the significance of oral streptococci in biofilm dynamics and how the perturbation may impact mucosal immunopathogenesis in the context of cancer, with a vision of exploiting oral streptococci for cancer intervention and for the development of non-invasive cancer diagnosis.

SPINT2 mutations in the Kunitz domain 2 found in SCSD patients inactivate HAI-2 as prostasin inhibitor via abnormal protein folding and N-glycosylation.

Mutations in the Kunitz-type serine protease inhibitor HAI-2, encoded by SPINT2, are responsible for the pathogenesis of syndromic congenital sodium diarrhea (SCSD), an intractable secretory diarrhea of infancy. Some of the mutations cause defects in the functionally required Kunitz domain 1 and/or subcellular targeting signals. Almost all SCSD patients, however, harbor SPINT2 missense mutations that affect the functionally less important Kunitz domain 2. How theses single amino acid substitutions inactivate HAI-2 was, here, investigated by the doxycycline-inducible expression of three of these mutants in HAI-2-knockout Caco-2 human colorectal adenocarcinoma cells. Examining protein expressed from these HAI-2 mutants reveals that roughly 50% of the protein is synthesized as disulfide-linked oligomers that lose protease inhibitory activity due to the distortion of the Kunitz domains by disarrayed disulfide bonding. Although the remaining protein is synthesized as monomers, its glycosylation status suggests that the HAI-2 monomer remains in the immature, lightly glycosylated form, and is not converted to the heavily glycosylated mature form. Heavily glycosylated HAI-2 possesses full anti-protease activity and appropriate subcellular targeting signals, including the one embedded in the complex-type N-glycan. As predicted, these HAI-2 mutants cannot suppress the excessive prostasin proteolysis caused by HAI-2 deletion. The oligomerization and glycosylation defects have also been observed in a colorectal adenocarcinoma line that harbors one of these SPINT2 missense mutations. Our study reveals that the abnormal protein folding and N-glycosylation can cause widespread HAI-2 inactivation in SCSD patents.

Oral streptococci S. anginosus and S. mitis induce distinct morphological, inflammatory, and metabolic signatures in macrophages.

Oral streptococci, key players in oral biofilm formation, are implicated in oral dysbiosis and various clinical conditions, including dental caries, gingivitis, periodontal disease, and oral cancer. Specifically, Streptococcus anginosus is associated with esophageal, gastric, and pharyngeal cancers, while Streptococcus mitis is linked to oral cancer. However, no study has investigated the mechanistic links between these Streptococcus species and cancer-related inflammatory responses. As an initial step, we probed the innate immune response triggered by S. anginosus and S. mitis in RAW264.7 macrophages. These bacteria exerted time- and dose-dependent effects on macrophage morphology without affecting cell viability. Compared with untreated macrophages, macrophages infected with S. anginosus exhibited a robust proinflammatory response characterized by significantly increased levels of inflammatory cytokines and mediators, including TNF, IL-6, IL-1ß, NOS2, and COX2, accompanied by enhanced NF-κB activation. In contrast, S. mitis-infected macrophages failed to elicit a robust inflammatory response. Seahorse Xfe96 analysis revealed an increased extracellular acidification rate in macrophages infected with S. anginosus compared with S. mitis. At the 24-h time point, the presence of S. anginosus led to reduced extracellular itaconate, while S. mitis triggered increased itaconate levels, highlighting distinct metabolic profiles in macrophages during infection in contrast to aconitate decarboxylase expression observed at the 6-h time point. This initial investigation highlights how S. anginosus and S. mitis, two Gram-positive bacteria from the same genus, can prompt distinct immune responses and metabolic shifts in macrophages during infection.IMPORTANCEThe surge in head and neck cancer cases among individuals devoid of typical risk factors such as Human Papilloma Virus (HPV) infection and tobacco and alcohol use sparks an argumentative discussion around the emerging role of oral microbiota as a novel risk factor in oral squamous cell carcinoma (OSCC). While substantial research has dissected the gut microbiome's influence on physiology, the oral microbiome, notably oral streptococci, has been underappreciated during mucosal immunopathogenesis. Streptococcus anginosus, a viridans streptococci group, has been linked to abscess formation and an elevated presence in esophageal cancer and OSCC. The current study aims to probe the innate immune response to S. anginosus compared with the early colonizer Streptococcus mitis as an important first step toward understanding the impact of distinct oral Streptococcus species on the host immune response, which is an understudied determinant of OSCC development and progression.

Stratification of risk for emergent intracranial abnormalities in children with headaches: a Pediatric Emergency Care Applied Research Network (PECARN) study protocol.

INTRODUCTION: Headache is a common chief complaint of children presenting to emergency departments (EDs). Approximately 0.5%-1% will have emergent intracranial abnormalities (EIAs) such as brain tumours or strokes. However, more than one-third undergo emergent neuroimaging in the ED, resulting in a large number of children unnecessarily exposed to radiation. The overuse of neuroimaging in children with headaches in the ED is driven by clinician concern for life-threatening EIAs and lack of clarity regarding which clinical characteristics accurately identify children with EIAs. The study objective is to derive and internally validate a stratification model that accurately identifies the risk of EIA in children with headaches based on clinically sensible and reliable variables. METHODS AND ANALYSIS: Prospective cohort study of 28 000 children with headaches presenting to any of 18 EDs in the Pediatric Emergency Care Applied Research Network (PECARN). We include children aged 2-17 years with a chief complaint of headache. We exclude children with a clear non-intracranial alternative diagnosis, fever, neuroimaging within previous year, neurological or developmental condition such that patient history or physical examination may be unreliable, Glasgow Coma Scale score<14, intoxication, known pregnancy, history of intracranial surgery, known structural abnormality of the brain, pre-existing condition predisposing to an intracranial abnormality or intracranial hypertension, head injury within 14 days or not speaking English or Spanish. Clinicians complete a standardised history and physical examination of all eligible patients. Primary outcome is the presence of an EIA as determined by neuroimaging or clinical follow-up. We will use binary recursive partitioning and multiple regression analyses to create and internally validate the risk stratification model. ETHICS AND DISSEMINATION: Ethics approval was obtained for all participating sites from the University of Utah single Institutional Review Board. A waiver of informed consent was granted for collection of ED data. Verbal consent is obtained for follow-up contact. Results will be disseminated through international conferences, peer-reviewed publications, and open-access materials.

Evaluation of Host Constitutive and Ex Vivo Coccidioidal Antigen-Stimulated Immune Response in Dogs with Naturally Acquired Coccidioidomycosis.

The early innate immune response to coccidioidomycosis has proven to be pivotal in directing the adaptive immune response and disease outcome in mice and humans but is unexplored in dogs. The objectives of this study were to evaluate the innate immune profile of dogs with coccidioidomycosis and determine if differences exist based on the extent of infection (i.e., pulmonary or disseminated). A total of 28 dogs with coccidioidomycosis (pulmonary, n = 16; disseminated, n = 12) and 10 seronegative healthy controls were enrolled. Immunologic testing was performed immediately, without ex vivo incubation (i.e., constitutive), and after coccidioidal antigen stimulation of whole blood cultures. Whole blood cultures were incubated with a phosphate-buffered solution (PBS) (negative control) or a coccidioidal antigen (rCTS1 (105-310); 10 µg/mL) for 24 h. A validated canine-specific multiplex bead-based assay was used to measure 12 cytokines in plasma and cell culture supernatant. Serum C-reactive protein (CRP) was measured with an ELISA assay. Leukocyte expression of toll-like receptors (TLRs)2 and TLR4 was measured using flow cytometry. Dogs with coccidioidomycosis had higher constitutive plasma keratinocyte chemotactic (KC)-like concentrations (p = 0.02) and serum CRP concentrations compared to controls (p < 0.001). Moreover, dogs with pulmonary coccidioidomycosis had higher serum CRP concentrations than those with dissemination (p = 0.001). Peripheral blood leukocytes from dogs with coccidioidomycosis produced higher concentrations of tumor necrosis factor (TNF)-α (p = 0.0003), interleukin (IL)-6 (p = 0.04), interferon (IFN)-γ (p = 0.03), monocyte chemoattractant protein (MCP)-1 (p = 0.02), IL-10 (p = 0.02), and lower IL-8 (p = 0.003) in supernatants following coccidioidal antigen stimulation when compared to those from control dogs. There was no detectable difference between dogs with pulmonary and disseminated disease. No differences in constitutive or stimulated leukocyte TLR2 and TLR4 expression were found. These results provide information about the constitutive and coccidioidal antigen-specific stimulated immune profile in dogs with naturally acquired coccidioidomycosis.

ROS is a master regulator of in vitro matriptase activation.

Matriptase is a type II transmembrane serine protease that is widely expressed in normal epithelial cells and epithelial cancers. Studies have shown that regulation of matriptase expression and activation becomes deranged in several cancers and is associated with poor disease-free survival. Although the central mechanism of its activation has remained unknown, our lab has previously demonstrated that inflammatory conditions such as intracellular pH decrease strongly induces matriptase activation. In this investigation, we first demonstrate clear matriptase activation following Fulvestrant (ICI) and Tykerb (Lapatinib) treatment in HER2-amplified, estrogen receptor (ER)-positive BT474, MDA-MB-361 and ZR-75-30 or single ER-positive MCF7 cells, respectively. This activation modestly involved Phosphoinositide 3-kinase (PI3K) activation and occurred as quickly as six hours post treatment. We also demonstrate that matriptase activation is not a universal hallmark of stress, with Etoposide treated cells showing a larger degree of matriptase activation than Lapatinib and ICI-treated cells. While etoposide toxicity has been shown to be mediated through reactive oxygen species (ROS) and MAPK/ERK kinase (MEK) activity, MEK activity showed no correlation with matriptase activation. Novelly, we demonstrate that endogenous and exogenous matriptase activation are ROS-mediated in vitro and inhibited by N-acetylcysteine (NAC). Lastly, we demonstrate matriptase-directed NAC treatment results in apoptosis of several breast cancer cell lines either alone or in combination with clinically used therapeutics. These data demonstrate the contribution of ROS-mediated survival, its independence of kinase-mediated survival, and the plausibility of using matriptase activation to indicate the potential success of antioxidant therapy.

Differential subcellular distribution renders HAI-2 a less effective protease inhibitor than HAI-1 in the control of extracellular matriptase proteolytic activity.

The integral membrane, Kunitz-type serine protease inhibitors HAI-1 and HAI-2, can suppress the proteolytic activity of the type 2 transmembrane serine protease matriptase with high specificity and potency. High levels of extracellular matriptase proteolytic activity have, however, been observed in some neoplastic B-cells with high levels of endogenous HAI-2, indicating that HAI-2 may be an ineffective matriptase inhibitor at the cellular level. The different effectiveness of the HAIs in the control of extracellular matriptase proteolytic activity is examined here. Upon inducing matriptase zymogen activation in the HAI Teton Daudi Burkitt lymphoma cells, which naturally express matriptase with very low levels of HAI-2 and no HAI-1, nascent active matriptase was rapidly inhibited or shed as an enzymatically active enzyme. With increasing HAI-1 expression, cellular matriptase-HAI-1 complex increased, and extracellular active matriptase decreased proportionally. Increasing HAI-2 expression, however, resulted in cellular matriptase-HAI-2 complex levels reaching a plateau, while extracellular active matriptase remained high. In contrast to this differential effect, both HAI-1 and HAI-2, even at very low levels, were shown to promote the expression and cell-surface translocation of endogenous matriptase. The difference in the suppression of extracellular active matriptase by the two closely related serine protease inhibitors could result from the primarily cell surface expression of HAI-1 compared to the mainly intracellular localization of HAI-2. The HAIs, therefore, resemble one another with respect to promoting matriptase expression and surface translocation but differ in their effectiveness in the control of extracellular matriptase enzymatic activity.

Isothermal Microcalorimetry Improves the Time to Diagnosis of Fracture-related Infection Compared With Conventional Tissue Cultures.

BACKGROUND: A consensus definition recently was formulated for fracture-related infection, which centered on confirmatory criteria including conventional cultures that take time to finalize and have a 10% to 20% false-negative rate. During this time, patients are often on broad-spectrum antibiotics and may remain hospitalized until cultures are finalized to adjust antibiotic regimens. QUESTIONS/PURPOSES: (1) What is the diagnostic accuracy of isothermal microcalorimetry, and how does its accuracy compare with that of conventional cultures? (2) Does isothermal microcalorimetry decrease time to detection (or diagnosis) of fracture-related infection compared with conventional cultures? (3) Does isothermal microcalorimetry have a diagnostic accuracy or time advantage over conventional cultures in patients on chronic suppressive antibiotics? METHODS: Between July 2020 and August 2021, we treated 310 patients with concerns for infection after prior fracture repair surgery. Of those, we considered all patients older than 18 years of age with fixation hardware in place at the time of presentation as potentially eligible. All included patients returned to the operating room with cultures obtained and assessed by both isothermal microcalorimetry and conventional cultures, and all were diagnosed using the consensus criteria for fracture-related infection. Based on that, 81% (250 of 310) of patients were eligible; a further 51% (157 of 310) were excluded because of the following reasons: the capacity of the isothermal microcalorimetry instrument limited the throughput on that day (34% [106 of 310]), they had only swab cultures obtained in surgery (15% [46 of 310]), or they had less than 3 months follow-up after surgery for infectious concerns (2% [5 of 310]), leaving 30% (93 of 310) of the originally identified patients for analysis. We obtained two to five cultures from each patient during surgery, which were sent to our clinical microbiology laboratory for standard processing (conventional cultures). This included homogenization of each tissue sample individually and culturing for aerobic, anaerobic, acid-fast bacilli, and fungal culturing. The remaining homogenate from each sample was then taken to our orthopaedic research laboratory, resuspended in growth media, and analyzed by isothermal microcalorimetry for a minimum of 24 hours. Aerobic and anaerobic cultures were maintained for 5 days and 14 days, respectively. Overall, there were 93 patients (59 males), with a mean age of 43 ± 14 years and a mean BMI of 28 ± 8 kg/m 2 , and 305 tissue samples (mean 3 ± 1 samples per patient) were obtained and assessed by conventional culturing and isothermal microcalorimetry. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of isothermal microcalorimetry to diagnose fracture-related infection were compared with conventional cultures using a McNemar test based on the consensus definition of fracture-related infection. This consensus criteria is comprised of two levels of certainty for the diagnostic variables. The first is confirmatory criteria, where infection is considered definitely present and includes the presence of fistula/sinus tract/wound breakdown, purulent drainage or the presence of pus, presence of microorganisms in deep tissue specimens on histopathologic examination, presence of more than five neutrophils/high-powered field by histopathologic examination (only for chronic/late onset cases), and identification of phenotypically indistinguishable pathogens by conventional culture from at least two separate deep tissue/implant specimens. The second is suggestive criteria in which further investigation is required to achieve confirmatory status. Fracture-related infection was diagnosed for this study to minimize subjectivity based on the presence of at least one of the confirmatory criteria as documented by the managing surgeon. When suggestive criteria were present without confirmatory criteria, patients were considered negative for fracture-related infection and followed further in clinic after surgical exploration (n = 25 patients). All 25 patients deemed not to have fracture-related infection were considered infection-free at latest follow-up (range 3 to 12 months). The time to detection or diagnosis was recorded and compared via the Mann-Whitney U test. RESULTS: Using the consensus criteria for fracture-related infection, there were no differences with the numbers available between isothermal microcalorimetry and conventional cultures in terms of sensitivity (87% [95% confidence interval 77% to 94%] versus 81% [95% CI 69% to 89%]), specificity (100% [95% CI 87% to 100%] versus 96% [95% CI 79% to 99%]), PPV (100% [95% CI 90% to 100%] versus 98% [95% CI 89% to 99%]), NPV (74% [95% CI 60% to 84%] versus 65% [95% CI 52% to 75%]), or accuracy (90% [95% CI 83% to 96%] versus 85% [95% CI 76% to 91%]; p = 0.13). The concordance by sample between conventional cultures and isothermal microcalorimetry was 85%. Isothermal microcalorimetry had a shorter median (range) time to detection or diagnosis compared with conventional cultures (2 hours [0.5 to 66] versus 51 hours [18 to 147], difference of medians 49 hours; p < 0.001). Additionally, 32 patients used antibiotics for a median (range) duration of 28 days (7 to 1095) before presentation. In these unique patients, there were no differences with the numbers available between isothermal microcalorimetry and conventional cultures in terms of sensitivity (89% [95% CI 71% to 98%] versus 74% [95% CI 53% to 88%]), specificity (100% [95% CI 48% to 100%] versus 83% [95% CI 36% to 99%]), PPV (100% [95% CI 85% to 100%] versus 95% [95% CI 77% to 99%]), NPV (63% [95% CI 37% to 83%] versus 42% [95% CI 26% to 60%]), or accuracy (91% [95% CI 75% to 98%] versus 78% [95% CI 57% to 89%]; p = 0.17). Isothermal microcalorimetry again had a shorter median (range) time to detection or diagnosis compared with conventional cultures (1.5 hours [0.5 to 48] versus 51.5 hours [18 to 125], difference of medians 50 hours; p < 0.001). CONCLUSION: Given that isothermal microcalorimetry considerably decreases the time to the diagnosis of a fracture-related infection without compromising the accuracy of the diagnosis, managing teams may eventually use isothermal microcalorimetry-pending developmental improvements and regulatory approval-to rapidly detect infection and begin antibiotic management while awaiting speciation and susceptibility testing to modify the antibiotic regimen. Given the unique thermograms generated, further studies are already underway focusing on speciation based on heat curves alone. Additionally, increased study sizes are necessary for both overall fracture-related infection diagnostic accuracy and test performance on patients using long-term antibiotics given the promising results with regard to time to detection for this groups as well. LEVEL OF EVIDENCE: Level II, diagnostic study.

Postinterview Communication in Orthopaedic Surgery Residency Interviews: A Survey of Match Applicants.

Background: To maintain the integrity of the match, postinterview communication (PIC) from programs to applicants is monitored and discouraged. The most recent report on the prevalence of PIC in orthopaedics found that 64% of surveyed applicants in 2014 and 2015 had received some form of PIC during their match cycle. In July 2019, the American Orthopaedic Association's Council of Orthopaedic Residency Directors (AOA/CORD) released a guideline recommending the elimination of all PIC in any form. The goal of this follow-up study was to determine the current prevalence of PIC with orthopaedic surgery applicants and assess the perspectives of medical students who recently applied for orthopaedic surgery residency positions. Methods: A 35-question survey was e-mailed to all orthopaedic surgery residency applicants of 4 geographically diverse residency programs in postmatch March 2020. The survey was open for 1 month, and the responses were reported using descriptive statistics. Results: Of the 229 respondents (21% response rate), 91 (39.7%) received PIC during the 2019 to 2020 residency match cycle. The program director was most commonly identified (80.2%) as the person who communicated with the applicants. At the interview day, 198 respondents (86.5%) were told that programs would not be contacting the applicants with PIC. However, over a quarter of respondents (25.3%) who received PIC answered that those programs contacted applicants after announcing they would not. Nearly half of the respondents (48.5%) agreed or strongly agreed that PIC causes added stress on applicants, and over half (52.9%) agreed or strongly agreed that all programs should stop participating in any form of PIC. Conclusions: Although the prevalence of PIC seems to have decreased since the 2014 and 2015 match, there is still room for improvement toward eliminating PIC. The AOA/CORD position statement from July 2019 should be disseminated to all members of the residency selection team to ensure consistency from all programs. The primary limitation of this study was the 21% response rate. Level of Evidence: Level IV (survey study).

N,N-Dimethyldithiocarbamate Elicits Pneumococcal Hypersensitivity to Copper and Macrophage-Mediated Clearance.

Streptococcus pneumoniae is a Gram-positive, encapsulated bacterium that is a significant cause of disease burden in pediatric and elderly populations. The rise in unencapsulated disease-causing strains and antimicrobial resistance in S. pneumoniae has increased the need for developing new antimicrobial strategies. Recent work by our laboratory has identified N,N-dimethyldithiocarbamate (DMDC) as a copper-dependent antimicrobial against bacterial, fungal, and parasitic pathogens. As a bactericidal antibiotic against S. pneumoniae, DMDC's ability to work as a copper-dependent antibiotic and its ability to work in vivo warranted further investigation. Here, our group studied the mechanisms of action of DMDC under various medium and excess-metal conditions and investigated DMDC's interactions with the innate immune system in vitro and in vivo. Of note, we found that DMDC plus copper significantly increased the internal copper concentration, hydrogen peroxide stress, nitric oxide stress, and the in vitro macrophage killing efficiency and decreased capsule. Furthermore, we found that in vivo DMDC treatment increased the quantity of innate immune cells in the lung during infection. Taken together, this study provides mechanistic insights regarding DMDC's activity as an antibiotic at the host-pathogen interface.

Extensive evaluation of ATAC-seq protocols for native or formaldehyde-fixed nuclei.

BACKGROUND: The "Assay for Transposase Accessible Chromatin sequencing" (ATAC-seq) is an efficient and easy to implement protocol to measure chromatin accessibility that has been widely used in multiple applications studying gene regulation. While several modifications or variants of the protocol have been published since it was first described, there has not yet been an extensive evaluation of the effects of specific protocol choices head-to-head in a consistent experimental setting. In this study, we tested multiple protocol options for major ATAC-seq components (including three reaction buffers, two reaction temperatures, two enzyme sources, and the use of either native or fixed nuclei) in a well-characterized cell line. With all possible combinations of components, we created 24 experimental conditions with four replicates for each (a total of 96 samples). In addition, we tested the 12 native conditions in a primary sample type (mouse lung tissue) with two different input amounts. Through these extensive comparisons, we were able to observe the effect of different ATAC-seq conditions on data quality and to examine the utility and potential redundancy of various quality metrics. RESULTS: In general, native samples yielded more peaks (particularly at loci not overlapping transcription start sites) than fixed samples, and the temperature at which the enzymatic reaction was carried out had a major impact on data quality metrics for both fixed and native nuclei. However, the effect of various conditions tested was not always consistent between the native and fixed samples. For example, the Nextera and Omni buffers were largely interchangeable across all other conditions, while the THS buffer resulted in markedly different profiles in native samples. In-house and commercial enzymes performed similarly. CONCLUSIONS: We found that the relationship between commonly used measures of library quality differed across temperature and fixation, and so evaluating multiple metrics in assessing the quality of a sample is recommended. Notably, we also found that these choices can bias the functional class of elements profiled and so we recommend evaluating several formulations in any new experiments. Finally, we hope the ATAC-seq workflow formulated in this study on crosslinked samples will help to profile archival clinical specimens.

Ankle Fracture and Length of Stay in US Adult Population Using Data From the National COVID Cohort Collaborative.

BACKGROUND: The National COVID Cohort Collaborative (N3C) is an innovative approach to integrate real-world clinical observations into a harmonized database during the time of the COVID-19 pandemic when clinical research on ankle fracture surgery is otherwise mostly limited to expert opinion and research letters. The purpose of this manuscript is to introduce the largest cohort of US ankle fracture surgery patients to date with a comparison between lab-confirmed COVID-19-positive and COVID-19-negative. METHODS: A retrospective cohort of adults with ankle fracture surgery using data from the N3C database with patients undergoing surgery between March 2020 and June 2021. The database is an NIH-funded platform through which the harmonized clinical data from 46 sites is stored. Patient characteristics included body mass index, Charlson Comorbidity Index, and smoking status. Outcomes included 30-day mortality, overall mortality, surgical site infection (SSI), deep SSI, acute kidney injury, pulmonary embolism, deep vein thrombosis, sepsis, time to surgery, and length of stay. COVID-19-positive patients were compared to COVID-19-negative controls to investigate perioperative outcomes during the pandemic. RESULTS: A total population of 8.4 million patient records was queried, identifying 4735 adults with ankle fracture surgery. The COVID-19-positive group (n=158, 3.3%) had significantly longer times to surgery (6.5 ± 6.6 vs 5.1 ± 5.5 days, P = .001) and longer lengths of stay (8.3 ± 23.5 vs 4.3 ± 7.4 days, P < .001), compared to the COVID-19-negative group. The COVID-19-positive group also had a higher rate of 30-day mortality. CONCLUSION: Patients with ankle fracture surgery had longer time to surgery and prolonged hospitalizations in COVID-19-positive patients compared to those who tested negative (average delay was about 1 day and increased length of hospitalization was about 4 days). Few perioperative events were observed in either group. Overall, the risks associated with COVID-19 were measurable but not substantial.Level of Evidence: Level III, retrospective cohort study.

Financial Literacy in Orthopaedic Surgery Residents: A COERG Survey.

INTRODUCTION: Financial literacy is the individual ability and skill to make informed decisions in the management of resources within the financial marketplace to yield a lifetime of financial well-being. Residents across several subspecialties have demonstrated low levels of financial literacy, and it is thought that more financial education is needed during residency training. The purpose of this study is to perform a comprehensive evaluation on financial literacy and financial attitudes of orthopaedic surgery residents. The authors hypothesize that orthopaedic residents will have low levels of financial literacy and financial satisfaction. METHODS: A 46-question anonymous survey was administered through COERG (Collaborative Orthopaedic Educational Research Group) to 1028 orthopaedic surgery residents of all postgraduate year at 43 programs with broad national distribution. Resident demographics and survey responses regarding knowledge of finance and investment topics, application of financial principles, and personal financial status were compared. RESULTS: The survey response rate was 48% (494/1028). The average financial literacy score of all orthopaedic resident participants was 60.9% (±16.5%). A total of 35.5% of orthopaedic residents were satisfied with their current financial situation. Saving for retirement and lower loan burdens correlated with greater financial satisfaction in financial situation. Scores were higher in orthopaedic residents with greater childhood annual household income, no credit card debt, higher levels of parent education, and active retirement savings plans. CONCLUSIONS: Orthopaedic residents show significant deficits in overall financial and investment knowledge combined with a dissatisfaction with financial situations while in residency. Orthopaedic residency programs have the opportunity to implement program-sponsored training and financial resources to enhance the resident education experience.

The US Medical Licensing Examination Step 1 Scoring Change: A Survey of Orthopaedic Surgery Residency Applicants From the 2019 to 2020 Match Cycle.

INTRODUCTION: The USMLE Step 1 examination has been used as an objective measure for comparing residency applicants. Recently, the National Board of Medical Examiners and the Federation of State Medical Boards decided that the USMLE Step 1 examination will transition to a pass/fail result starting no earlier than 2022. The purpose of this study was to investigate the perspective of medical students who applied for orthopaedic surgery residency positions during the 2019 to 2020 interview cycle on the USMLE scoring change, and the potential effect this change may result in for future applicants and the residency selection process. METHODS: A 15-item anonymous web-based survey was sent to 1,090 orthopaedic surgery residency applicants from four regionally diverse residency programs. The survey elicited attitudes toward the transition of the Step 1 examination to pass/fail and perspectives this change may or may not have on the residency selection process. RESULTS: Responses were received from 356 applicants (32.7%). The majority (61.6%) disagreed with the change to pass/fail scoring, and 68.5% do not believe that the change will decrease stress levels in medical students. For interview invitations, respondents chose Step 2 clinical knowledge, letters of recommendation, and performance on away rotations as the most influential factors in the absence of a Step 1 score. CONCLUSION: Most of the students surveyed who applied for an orthopaedic surgery residency position during the most recent application cycle disagreed with the National Board of Medical Examiner/Federation of State Medical Board decision to change Step 1 to pass/fail and feel that this change may have disadvantage in certain student groups while either increasing or having no effect on medical student stress. LEVEL OF EVIDENCE: IV.

Prevalence, Bias, and Rank List Impact of Illegal Questions in Surgical Specialty Residency Interviews.

OBJECTIVE: The purpose of this study is to characterize illegal questions as defined by federal law and to assess their impact on applicants' rank lists across four surgical specialties. DESIGN: A survey was developed and sent to surgical specialty residency applicants. The survey asked demographics, the frequency of questions about age, gender, religion, sexual orientation, family status and impact on final rank list. Applicants were asked to respond anonymously based on their experience at all institutions at which they interviewed during the interview cycle. Results were compared by applicant specialty and gender. SETTING: A large university-affiliated academic medical center PARTICIPANTS: Survey was administered to 3854 applicants (comprising between 28.9% and 41.2% of applicants nationwide) to general surgery, orthopaedic surgery, urology, and otolaryngology residency programs at a single institution during the 2018 and 2019 cycles. A total of 1066 applicants completed the survey. RESULTS: A total of 789 (74.0%) of applicants reported being asked at least one illegal question during the interview process at any institution. Applicants to orthopaedic surgery programs were most likely to be asked illegal question (n = 315, 81.6%), and general surgery applicants were least likely to be asked illegal questions (n = 324, 66.8%, p < 0.001). Females were more likely than males to be asked about gender (n = 99, 26.3% vs. n = 18, 2.6%, p < 0.001) and plans for pregnancy (n = 78, 20.8% vs. n = 78, 11.4%, p < 0.001). 152 (19.4%). Applicants reported that being asked an illegal question lowered a program on their rank list. Female applicants were more likely to lower a program on their rank list as a result of an illegal question (n = 102, 35.4% vs. n = 50, 10.1%, p < 0.001). CONCLUSIONS: Illegal questions in surgical specialty residency interviews are common, vary by specialty and applicant gender, and lower programs on applicants' rank lists. This data should serve to inform larger and more inclusive studies in the future. Programs should focus on educating interviewers on illegal topics in an effort to minimize illegal topics that may alienate applicants and contribute to workplace discrimination.

What Are the Risk Factors for Infection After Operative Treatment of Peritalar Fracture Dislocations?

OBJECTIVE: To assess the risk factors associated with deep infection after operative treatment of peritalar fracture dislocations. DESIGN: A retrospective study was performed to identify patients who had operative treatment of a peritalar fracture dislocation over an 11-year period (2008-2019). SETTING: Level 1 trauma center. PARTICIPANTS: Patients were identified by review of all surgical billing that included open reduction of peritalar dislocation. Minimum follow-up for inclusion was 3 months or the outcome of interest. A total of 178 patients were identified, and 154 patients met inclusion criteria. MAIN OUTCOME: The primary outcome was deep infection, defined as return to the operating room for debridement with positive cultures. RESULTS: A total of 19 (12.3%) patients developed a postoperative deep infection. The most common associated fractures were talus (47%), calcaneus (33%), and fibula (9%) fractures. The infected group was significantly older (47.2 vs. 39.5 years, P = 0.03). Patients undergoing operative management for peritalar fracture dislocations with current smoking were found to have significantly higher odds of postoperative deep infection (74 vs. 34%, adjusted odds ratio = 7.4, 95% confidence interval, 2.3-24.1, P = 0.001). There was a significantly higher risk of infection in patients with a Gustilo-Anderson type 3 open fracture (32 vs. 12%, adjusted odds ratio = 5.7, 95% confidence interval, 1.6-20.3, P = 0.007). The infected group had high rates of below knee amputation when compared with the group without infection (47 vs. 1%, P < 0.001). CONCLUSION: In our retrospective study, risk factors for infection after peritalar fracture dislocation included older age, smoking, and Gustilo-Anderson type 3 open fracture. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Targeted HAI-2 deletion causes excessive proteolysis with prolonged active prostasin and depletion of HAI-1 monomer in intestinal but not epidermal epithelial cells.

Mutations of SPINT2, the gene encoding the integral membrane, Kunitz-type serine inhibitor HAI-2, primarily affect the intestine, while sparing many other HAI-2-expressing tissues, causing sodium loss in patients with syndromic congenital sodium diarrhea. The membrane-bound serine protease prostasin was previously identified as a HAI-2 target protease in intestinal tissues but not in the skin. In both tissues, the highly related inhibitor HAI-1 is, however, the default inhibitor for prostasin and the type 2 transmembrane serine protease matriptase. This cell-type selective functional linkage may contribute to the organ-selective damage associated with SPINT 2 mutations. To this end, the impact of HAI-2 deletion on matriptase and prostasin proteolysis was, here, compared using Caco-2 human colorectal adenocarcinoma cells and HaCaT human keratinocytes. Greatly enhanced prostasin proteolytic activity with a prolonged half-life and significant depletion of HAI-1 monomer were observed with HAI-2 loss in Caco-2 cells but not HaCaT cells. The constitutive, high level prostasin zymogen activation observed in Caco-2 cells, but not in HaCaT cells, also contributes to the excessive prostasin proteolytic activity caused by HAI-2 loss. HAI-2 deletion also caused increased matriptase zymogen activation, likely as an indirect result of increased prostasin proteolysis. This increase in activated matriptase, however, only had a negligible role in depletion of HAI-1 monomer. Our study suggests that the constitutive, high level of prostasin zymogen activation and the cell-type selective functional relationship between HAI-2 and prostasin renders Caco-2 cells more susceptible than HaCaT cells to the loss of HAI-2, causing a severe imbalance favoring prostasin proteolysis.

Incidence of supraventricular tachycardia after inhaled short-acting beta agonist treatment in children.

INTRODUCTION: Albuterol can trigger supraventricular tachycardia (SVT). The clinical characteristics, incidence, and risk factors of SVT after inhaled SABA treatment in children are currently unknown. Through review of regional care delivery, we will describe cases of SVT during asthma treatment in hospital-based settings, define the incidence of SVT in our population, and evaluate risk factors of SABA-induced SVT. METHODS: We identified hospital-based care episodes of children 0-18 years old between 2006 and 2015 recorded in the Intermountain Healthcare EDW with either 1) diagnosis codes for both asthma and SVT or 2) both SABA and adenosine listed as billed medications. Controls were matched with cases by age and sex to determine risk factors for SVT after SABA using conditional logistic regression. RESULTS: Of 93 care episodes meeting criteria, we found 7 cases of SVT after SABA treatment in 6 patients over 10 years. In our population, the incidence of SVT is 3.9 per 10,000 episodes of SABA treatment, and 5.1 per 10,000 children with asthma receiving hospital-based asthma care. Two episodes of SVT followed treatment with only levalbuterol, three after only albuterol, and two after both albuterol and levalbuterol treatment. Five cases of SVT were converted to sinus rhythm with adenosine, one converted with synchronized electrical cardioversion, and one resolved spontaneously. No cases of SVT led to death. No examined variables were associated with SABA-induced SVT. CONCLUSIONS: SVT is rare during hospital-based treatment for acute asthma using inhaled SABAs and has low morbidity and mortality.

Applications of the transfibular approach to the hindfoot: A systematic review and description of a preferred technique.

BACKGROUND: The indications and technique for the transfibular approach to the tibiotalar joint have evolved since its initial popularization in 1942. The purpose of this systematic review is to assess the indications, techniques, and postoperative outcomes among procedures performed with the transfibular approach. METHODS: A comprehensive search of PubMed, Medline, and Embase databases from 1942 to 2018 was performed in accordance with PRISMA guidelines. After an initial broad search of transfibular approach indications, articles were stratified into 4 major surgical categories for assessment: (1) tibiotalar arthrodesis (2) tibiotalocalcaneal arthrodesis (3) total ankle replacement and (4) distal tibial tumor excision. Data was analyzed according to these 4 categories. RESULTS: A total of 32 studies (874 ankles) were included. Fibular non-union rates were 0.7 % (5 of 672) across all studies, 0.6% (2 of 329) for tibiotalar arthrodesis, 0.0% (0 of 12) for tibiotalocalcaneal arthrodesis, 1.0 % (3 of 296) for total ankle arthroplasty and 0.0% (0 of 15) for other procedures. Rates of deep infection were 2.5% (23 of 903) across all studies, 3.2% (15 of 466) for tibiotalar arthrodesis, 3.7% (4 of 106) for tibiotalocalcaneal arthrodesis, 1.3% (4 of 296) for total ankle arthroplasty, and 0.0% (0 of 15) for other procedures. CONCLUSIONS: The transfibular approach is useful for cases requiring extensile exposure of the tibiotalar joint. This study provides evidence that the transfibular approach yields satisfactory results, with low complication and infection rates. LEVEL OF EVIDENCE: IV.

Factors Associated with Low and High Article Citations in Four Prominent Orthopaedic Surgery Journals.

BACKGROUND: Research is a cornerstone for the advancement of clinical practice and guidelines across all medical and surgical fields. To achieve significant contribution to the field, research must be circulated, read, and understood. PURPOSE: The purpose of this paper is to investigate which factors are associated with higher and lower citation rates in orthopaedic surgery literature. METHODS: A query was performed to identify all of the primary research articles published between 1998 and 2008 in four prominent orthopaedics journals. From there, the 50 most highly and lowly cited articles were identified and analyzed for various factors that distinguished the highly cited group from the lowly cited group. Various statistical tests were used depending on the type of variable being evaluated. RESULTS: After data compilation and statistical analysis, 16 statistically significant factors were apparent that differed between the two groups. Seven non-statistically significant factors were also identified. CONCLUSION: This study illustrates that certain statistically significant factors influence the citation rates of papers in orthopaedic surgery literature. If utilized appropriately, these factors could lead to increased consumption and circulation of future orthopaedic surgery literature.