Expression patterns of melanin-related genes are linked to crypsis and conspicuousness in a pumpkin toadlet.

Colour signals play pivotal roles in different communication systems, and the evolution of these characters has been associated with behavioural ecology, integumentary production processes and perceptual mechanisms of the species involved. Here, we present the first insight into the molecular and histological basis of skin colour polymorphism within a miniaturized species of pumpkin toadlet, potentially representing the lowest size threshold for colour polytypism in tetrapods. Brachycephalus actaeus exhibits a coloration ranging from cryptic green to conspicuous orange skin, and our findings suggest that colour morphs differ in their capability to be detected by potential predators. We also found that the distribution and abundance of chromatophores are variable in the different colour morphs. The expression pattern of coloration related genes was predominantly associated with melanin synthesis (including dct, edn1, mlana, oca2, pmel, slc24a5, tyrp1 and wnt9a). Up-regulation of melanin genes in grey, green and brown skin was associated with higher melanophore abundance than in orange skin, where xanthophores predominate. Our findings provide a significant foundation for comparing and understanding the diverse pathways that contribute to the evolution of pigment production in the skin of amphibians.

The function of prolonged copulations in Enchenopa treehoppers (Hemiptera: Membracidae).

Copulations are very brief in many species, sometimes taking only seconds, but in other species, they can be quite prolonged. Potential explanations for prolonged copulations include time requirements for the transfer of sperm and/or other ejaculate substances. Ejaculate substances could function to regulate female receptivity to subsequent matings, provide nutritional nuptial gifts, or hasten egg oviposition at a potential survival cost to the female. We investigated prolonged copulation in a member of the Enchenopa binotata complex of treehoppers (Hemiptera: Membracidae), in which females rarely remate and copulation can last several hours. We assigned females to treatments in which we interrupted copulation at different times. We also included a control where copulation was not interrupted. We found that females that experienced shorter copulations were more likely to be subsequently receptive to an attractive male. We also found that few females produced offspring when they engaged in short copulations compared to those with longer copulations. We did not find any differences in female survival. Our results support the sperm transfer and receptivity regulation hypotheses. We discuss potential reasons for why these processes should take so long in a species with low female remating.

On the function of a female-like signal type in the vibrational repertoire of Enchenopa male treehoppers (Hemiptera: Membracidae).

Animals often mimic the behaviours or signals of conspecifics of the opposite sex while courting. We explored the potential functions of a novel female-like signal type in the courtship displays of male Enchenopa treehoppers. In these plant-feeding insects, males produce plant-borne vibrational advertisement signals, to which females respond with their own duetting signals. Males also produce a signal type that resembles the female duetting responses. We experimentally tested whether this signal modifies the behaviour of receivers. First, we tested whether the female-like signal would increase the likelihood of a female response. However, females were as likely to respond to playbacks with or without them. Second, we tested whether the female-like signal would inhibit competing males, but males were as likely to produce displays after playbacks with or without them. Hence, we found no evidence that this signal has an adaptive function, despite its presence in the courtship display, where sexual selection affects signal features. Given these findings, we also explored whether the behavioural and morphological factors of the males were associated with the production of the female-like signal. Males that produced this signal had higher signalling effort (longer and more frequent signals) than males that did not produce it, despite being in worse body condition. Lastly, most males were consistent over time in producing the female-like signal or not. These findings suggest that condition-dependent or motivational factors explain the presence of the female-like signal. Alternatively, this signal might not bear an adaptive function, and it could be a way for males to warm up or practice signalling, or even be a by-product of how signals are transmitted through the plant. We suggest further work that might explain our puzzling finding that a signal in the reproductive context might not have an adaptive function.

Semaglutide Use Prior to Total Hip Arthroplasty Results in Fewer Postoperative Prosthetic Joint Infections and Readmissions.

BACKGROUND: Semaglutide, a novel diabetes management medication, is known for its efficacy in inducing weight loss. Despite this, its impact on outcomes after total hip arthroplasty (THA) remains unclear. The aim of this study was to evaluate if THA patients on semaglutide demonstrate: (1) fewer medical complications; (2) fewer implant-related complications; (3) fewer readmissions; and (4) lower costs. METHODS: Using a national claims database from 2010 to 2021, we retrospectively examined diabetic patients prescribed semaglutide who underwent primary THA. This yielded 9,465 patients (Semaglutide = 1,653; Control = 7,812). Multivariable logistic regression was used to evaluate the following outcomes: 90-day postoperative medical complications, 2-year implant-related complications, 90-day readmissions, in-hospital lengths of stay, and day-of-surgery and 90-day episode of care costs. RESULTS: Semaglutide users exhibited lower 90-day readmission rates (6.2 versus 8.8%; odds ratio 0.68; P < .01) and reduced prosthetic joint infections (1.6 versus 2.9%; odds ratio 0.56; P < .01). However, medical complication rates, hospital stays, same-day surgical costs, and 90-day episode costs showed no significant differences. CONCLUSIONS: This study highlights semaglutide users undergoing THA with fewer 90-day readmissions and 2-year prosthetic joint infections. Although no variance appeared in medical complications, hospital stays, or costs, the medication's notable glycemic control and weight loss benefits could prompt pre-surgery consideration. Further research is essential for a comprehensive understanding of semaglutide's impact on post-THA outcomes.

History of Diabetic Foot Ulcer is Associated With Increased Risk of Prosthetic Joint Infection and Sepsis After Total Joint Arthroplasty.

BACKGROUND: Diabetic foot ulcers (DFUs) are common sequelae of diabetes mellitus. Currently, the effect of DFUs on total joint arthroplasty (TJA) outcomes is sparsely evaluated. This study investigated whether DFU patients undergoing TJA increases risk of (1) prosthetic joint infections (PJI), (2) surgical site infections (SSI), (3) sepsis, (4) readmissions, and (5) revisions. METHODS: Using PearlDiver, a retrospective query from January 1, 2010 to October 31, 2020 was performed. DFU patients undergoing total knee arthroplasty (TKA) and total hip arthroplasty (THA) were included and 1:5 propensity score matched with controls using age, sex, body mass index, and various comorbidities (33,155 TKA patients [DFU = 5,529; control = 27,626]; 17,146 THA patients [DFU = 2,862; control = 14,284]). Outcomes included rates of PJI, SSI, sepsis, readmissions, and revisions. Multivariate logistical regressions calculated odds ratios (ORs), 95% confidence intervals, and P values (P < .001 as significance threshold). RESULTS: DFU increased risk of sepsis within 90 days of TKA (OR 4.59; P < .001) and THA (OR 4.87; P < .001). DFU did not increase risk of PJI at 90 days for TKA (OR 0.8; P = .1) or THA (OR 0.85; P = .34) but did by 2 years post-TKA (OR 1.51; P < .001) and THA (OR 1.55; P < .001). Risk of SSI increased in DFU cohort following TKA and THA at 90 days and 2 years and at 90-day readmissions and 2-year revisions. CONCLUSION: DFU patients undergoing TJA demonstrated increased risk of postoperative sepsis and PJI. Furthermore, DFU patients demonstrated an increased risk of SSI, readmissions, and revisions. Providers should counsel DFU patients about postoperative risks.

Assessing Ability for ChatGPT to Answer Total Knee Arthroplasty-Related Questions.

BACKGROUND: Artificial intelligence in the field of orthopaedics has been a topic of increasing interest and opportunity in recent years. Its applications are widespread both for physicians and patients, including use in clinical decision-making, in the operating room, and in research. In this study, we aimed to assess the quality of ChatGPT answers when asked questions related to total knee arthroplasty. METHODS: ChatGPT prompts were created by turning 15 of the American Academy of Orthopaedic Surgeons Clinical Practice Guidelines into questions. An online survey was created, which included screenshots of each prompt and answers to the 15 questions. Surgeons were asked to grade ChatGPT answers from 1 to 5 based on their characteristics: (1) relevance, (2) accuracy, (3) clarity, (4) completeness, (5) evidence-based, and (6) consistency. There were 11 Adult Joint Reconstruction fellowship-trained surgeons who completed the survey. Questions were subclassified based on the subject of the prompt: (1) risk factors, (2) implant/intraoperative, and (3) pain/functional outcomes. The average and standard deviation for all answers, as well as for each subgroup, were calculated. Inter-rater reliability (IRR) was also calculated. RESULTS: All answer characteristics were graded as being above average (ie, a score > 3). Relevance demonstrated the highest scores (4.43 ± 0.77) by surgeons surveyed, and consistency demonstrated the lowest scores (3.54 ± 1.10). ChatGPT prompts in the Risk Factors group demonstrated the best responses, while those in the Pain/Functional Outcome group demonstrated the lowest. The overall IRR was found to be 0.33 (poor reliability), with the highest IRR for relevance (0.43) and the lowest for evidence-based (0.28). CONCLUSIONS: ChatGPT can answer questions regarding well-established clinical guidelines in total knee arthroplasty with above-average accuracy but demonstrates variable reliability. This investigation is the first step in understanding large language model artificial intelligence like ChatGPT and how well they perform in the field of arthroplasty.

Comparison of Patient Demographics and Risk of Surgical Site Infections Following Open Reduction and Internal Fixation of Trimalleolar Ankle Fractures: A Nationwide Analysis of a Private Payor.

Surgical site infections (SSIs) are a notable complication following open reduction and internal fixation (ORIF) for ankle fractures. The purpose of this study was to (1) compare baseline demographics of patients who did and did not develop SSIs within 90 days following ORIF for trimalleolar ankle fractures and (2) identify risk factors associated with SSIs in this setting. A retrospective analysis from 2010 to 2020 was completed using a national administrative database. The study group consisted of patients who underwent ORIF for trimalleolar ankle fractures and developed SSIs within 90 days postoperatively. Patients without SSIs served as the comparison cohort. Baseline demographics of the two cohorts were compared utilizing Pearson's Chi-Square Analyses. A multivariate binomial logistic regression model determined the association of various comorbidities on developing SSIs in this setting. Out of a total sample of 22,118 patients, 1000 individuals (4.52%) developed SSIs. The study revealed that the SSI cohort exhibited a greater burden of comorbidities, as evidenced by significant differences in various individual comorbidities and average Elixhauser-Comorbidity Indices scores. The most strongly associated risk factors for the development of SSIs following ORIF for trimalleolar ankle fractures were peripheral vascular disease (OR: 1.53, p < .0001), diabetes mellitus (OR: 1.26, p = .0010), iron deficiency anemia (OR: 1.24, p = .0010), male sex (OR: 1.22, p = .0010), and tobacco use (OR: 1.15, p = .0010). This study identified several patient risk factors that were associated with developing SSIs after ORIF for trimalleolar ankle fractures, recognizing potential patient-directed interventions that may reduce the rate of SSIs in this setting.

The association of congestive heart failure on in-hospital lengths of stay, morbidity, and financial burden following primary total knee arthroplasty.

BACKGROUND: Current literature states that 6.2 million adults in the United States are living with heart failure. Studies investigating the impact of congestive heart failure (CHF) following primary total knee arthroplasty (TKA) are scarce. Hence, this research aimed to investigate whether individuals with congestive heart failure (CHF) undergoing primary total knee arthroplasty (TKA) experience: (1) longer durations of in-hospital stay; (2) increased incidences of health complications; and (3) a higher financial load. METHODS: A retrospective query using the 100% Parts A and B of the Medicare claims was performed. Cohorts of interest were identified using International Classification of Disease, Ninth Revision (ICD-9) and Current Procedural Terminology. Inclusion criteria for the study group consisted of patients with CHF undergoing primary TKA, whereas patients without CHF undergoing primary TKA served as the comparison cohort. RESULTS: The query yielded 1,101,169 patients (CHF = 183,540; case-matched = 917,629). Patients with CHF had longer in-hospital LOS (5- vs. 4-days) and a higher incidence and odds of developing 90-day medical complications (49.22% vs. 7.45%) following primary TKA. CHF patients incurred higher day of surgery and total global ninety-day episode of care costs compared to their matched counterparts. CONCLUSION: This study illustrated those patients with preexisting CHF undergoing a primary TKA have longer in-hospital lengths of stay and higher rates of morbidity and financial burden. With the increasing prevalence of CHF worldwide, orthopedists and other healthcare professionals can utilize the information provided in this study to educate patients and establish comprehensive treatment plans to help mitigate postoperative effects associated with CHF.

A matched-control study on the impact of depressive disorders following lumbar fusion for adult spinal deformity: an analysis of a nationwide administrative database.

PURPOSE: In recent years, depression rates have been on the rise, resulting in soaring mental health issues globally. There is paucity of literature about the impact of depression on lumbar fusion for adult spine deformity. The purpose of this study is to investigate whether patients with depressive disorders undergoing lumbar deformity fusion have higher rates of (1) in-hospital length of stay; (2) ninety-day medical and surgical complications; and (3) medical reimbursement. METHODS: A retrospective study was performed using a nationwide administrative claims database from January 2007 to December 2015 for patients undergoing lumbar fusion for spine deformity. Study participants with depressive disorders were selected and matched to controls by adjusting for sex, age, and comorbidities. In total, the query yielded 3706 patients, with 1286 who were experiencing symptoms of depressive disorders, and 2420 who served as the control cohort. RESULTS: The study revealed that patients with depressive disorders had significantly higher in-hospital length of stay (6.0 days vs. 5.0 days, p < 0.0001) compared to controls. Study group patients also had higher incidence and odds of ninety-day medical and surgical complications (10.2% vs. 5.0%; OR, 2.50; 95% CI, 2.16-2.89; p < .0001). Moreover, patients with depressive disorders had significantly higher episode of care reimbursement ($54,539.2 vs. $51,645.2, p < 0.0001). CONCLUSION: This study illustrated that even after controlling for factors such as sex, age, and comorbidities, patients with depressive disorders had higher rates of in-hospital length of stay, medical and surgical complications, and total reimbursement.

Comparison of patient demographics and patient-specific risk factors for readmissions following open reduction and internal fixation for acetabular fractures.

PURPOSE: Acetabular fractures are highly complex injuries often resulting from high-energy trauma. The gold standard treatment for these injuries has become open reduction internal fixation (ORIF). The purpose of this study is to further this understanding and investigate how (1) patient demographics and (2) patient-specific risk factors affect 90-day readmission rates. METHODS: A retrospective, nationwide query of private insurance database from January 1st, 2010 to October 31st, 2020 was performed using ICD-9, ICD-10, and CPT codes. Patients who underwent acetabular ORIF and were readmitted within 90 days following index procedure were included, patients who were not readmitted served as controls. Patients were divided by demographics and specific risk factors associated with readmission. RESULTS: The query yielded a total of 3942 patients. Age and sex were found to be non-significant contributing risk factors to 90-day readmissions. Data also showed that statistically significant comorbidities included arrhythmia, cerebrovascular disease, coagulopathy, fluid and electrolyte abnormalities, and pathologic weight loss. CONCLUSION: This study illustrated how several patient-specific risk factors may contribute to increased 90-day readmission risk following acetabular ORIF. A heightened awareness of these comorbidities in patients requiring acetabular ORIF is required to improve patient outcomes and minimize rates of readmission. Further investigation is needed to improve patient outcomes, and increase awareness of potential post-operative complications in these higher-risk patient populations.

Anterolateral knee complex considerations in contemporary anterior cruciate ligament reconstruction and total knee arthroplasty: a systematic review.

The anterolateral ligament (ALL) was first described in 1879 in the context of Segond fractures, which correlate with a 75-100% chance of an anterior cruciate ligament (ACL) tear or a 66-75% chance of a meniscal tear. The purpose of this paper is to provide an updated comprehensive review on the anterolateral ligament complex of the knee focusing on the: (1) anatomy of the ALL/ALC; (2) associated biomechanics/function; and (3) important surgical considerations in contemporary anterior cruciate ligament (ACL) reconstruction and total knee arthroplasty (TKA). A systematic review of studies on ALL was conducted on Pubmed/MEDLINE and Cochrane databases (May 7th, 2020 to February 1st, 2022), with 20 studies meeting inclusion/exclusion criteria. Studies meeting inclusion criteria were anatomical/biomechanical studies assessing ALL function, cadaveric and computer simulations, and comparative studies on surgical outcomes of ALLR (concomitant with ACL reconstruction). Eight studies were included and graded by MINOR and Newcastle-Ottawa scale to identify potential biases. The anatomy of the ALL is part of the anterolateral ligament complex (ALC), which includes the superficial/deep iliotibial band (including the Kaplan fiber system), iliopatellar band, ALL, and anterolateral capsule. Multiple biomechanical studies have characterized the ALC as a secondary passive stabilizer in resisting tibial internal rotation. Given the role of the ALC in resisting internal tibial rotation, lateral extra-articular procedures including ALL augmentation may be considered for chronic ACL tears, ACL revisions, and a high-grade pivot shift test. In the context of TKA, in the event of injury to the ALC, a more constrained implant or soft-tissue reconstruction may be necessary to restore appropriate knee stability.

Crohn's disease is associated with higher rates of implant-related complications following primary total knee arthroplasty.

INTRODUCTION: In Western countries, there has been a rise in the prevalence of Crohn's Disease (CD) and primary total knee arthroplasty (TKA). This study delves deeper into the effects of CD on TKA patients by examining (1) the length of in-hospital stay (LOS); (2) the rates of readmission; (3) complications related to implants; and (4) the costs associated with care. METHODS: A retrospective analysis using the PearlDiver database was conducted, encompassing the time frame between January 1st, 2005 and March 31st, 2014, focusing on patients who underwent TKA and were either diagnosed with CD or not. Patients with CD were paired with control subjects at a 1:5 ratio based on age, gender, and medical comorbidities. The analysis comprised a total of 96,229 patients (CD = 16,039; non-CD = 80,190). RESULTS: Patients with CD had a notably longer hospital stay (3 v. 2 days, p < 0.0001) and faced significantly higher rates of 90-day readmissions and complications (19.80% v. 14.91%, OR: 1.40, p < 0.0001; 6.88% v. 4.88%, OR: 1.43, p < 0.0001 respectively). Additionally, CD patients incurred greater expenses on the surgery day ($18,365.98 v. $16,192.00) and within 90 days post-surgery ($21,337.46 v. $19,101.42). CONCLUSION: This study demonstrates longer in-hospital LOS, higher rates of readmissions, implant-related complications, and costs of care among CD patients following primary TKA.

Does Semaglutide Use Decrease Complications and Costs Following Total Knee Arthroplasty?

BACKGROUND: Diabetes mellitus (DM) and obesity are associated with total knee arthroplasty (TKA) complications. Semaglutide, a medication for DM and weight loss, can potentially affect TKA outcomes. This study investigated whether semaglutide use during TKA demonstrates fewer: (1) medical complications; (2) implant-related complications; (3) readmissions; and (4) costs. METHODS: A retrospective query was performed using a National database to 2021. Patients undergoing TKA for osteoarthritis with DM and semaglutide use were successfully propensity score-matched to controls semaglutide = 7,051; control = 34,524. Outcomes included 90-day postoperative medical complications, 2-year implant-related complications, 90-day readmissions, in-hospital lengths of stay, and costs. Multivariate logistical regressions calculated odds ratios (ORs), 95% confidence intervals, and P values (P < .003 as significance threshold after Bonferroni correction). RESULTS: Semaglutide cohorts had higher incidence and odds of myocardial infarction (1.0 versus 0.7%; OR 1.49; P = .003), acute kidney injury (4.9 versus 3.9%; OR 1.28; P < .001), pneumonia (2.8 versus 1.7%; OR 1.67; P < .001), and hypoglycemic events (1.9 versus 1.2%; OR 1.55; P < .001), but lower odds of sepsis (0 versus 0.4%; OR 0.23; P < .001). Semaglutide cohorts also had lower odds of prosthetic joint infections (2.1 versus 3.0%; OR 0.70; P < .001) and readmission (7.0 versus 9.4%; OR 0.71; P < .001), and trended toward lower odds of revisions (4.0 versus 4.5%; OR 0.86; P = .02) and 90-day costs ($15,291.66 versus $16,798.46; P = .012). CONCLUSION: Semaglutide use during TKA decreased risk for sepsis, prosthetic joint infections, and readmissions, but also increased risk for myocardial infarction, acute kidney injury, pneumonia, and hypoglycemic events.

Clostridium difficile colitis following geriatric hip fracture surgery: incidence, trends, and risk factors from 45,910 patients.

PURPOSE: Clostridium difficile colitis is a serious complication in elderly patients undergoing surgery. The objectives of this study were: (1) to use a nationwide sample of patients to report the incidence and timing of C. difficile colitis in geriatric patients who underwent surgery for hip fractures, (2) to identify preoperative factors associated with developing C. difficile colitis and mortality. METHODS: This was a retrospective evaluation of the 2016-2019 ACS Targeted Hip Fracture database merged with the ACS-NSQIP database. Patients undergoing surgery for hip fracture were included. Outcomes studied were incidence, preoperative, and postoperative risk factors for occurrence of C. difficile infection and mortality. Chi-squared tests were used to compare demographics between the patients infected (study) and not infected (control). Logistic regression models were utilized to compute the odds ratios (OR) testing for the association of independent factors on developing C. difficile infection postoperatively and mortality. A statistical threshold was set at p < 0.008. RESULTS: The incidence of C. difficile infection within 30 days of hip fracture surgery was 0.81%. Fifty percent of infections were diagnosed within 9 days postoperatively. Preoperative and hospital-associated factors associated with development of C. difficile infection were ≥ 2 days until operation (OR 1.88 [95% CI 1.39-2.55], p < 0.001) and dependent functional status (OR 1.43 [95% CI 1.14-1.79], p = 0.002). After adjusting for multiple comorbidities, increased age, male sex, COPD, CHF, dependent functional status, and C. difficile infection were associated with increased mortality within 30 days of surgery (all p < 0.001). CONCLUSION: Clostridium difficile colitis is a serious infection after hip fracture surgery in geriatric patients with an incidence of about 1%. Patients at increased risk should be targeted with preventative measures to prevent the morbidity from this complication.

Trends and risk factors for readmissions following press-fit total knee arthroplasty for the treatment of end-stage osteoarthritis of the knee: a five-year analysis.

INTRODUCTION: The development of new prostheses with improved osseointegration, bone preservation, and reduced cost has renewed interest in uncemented total knee arthroplasty (UCTKA). In the current study, we aimed to: (1) assess demographic data of patients who were and were not readmitted and (2) identify patient-specific risk factors associated with readmission. METHODS: A retrospective query from the PearlDiver database was performed from January 1, 2015, to October 31, 2020. International Classification of Disease, Ninth Revision (ICD-9), ICD-10, or Current Procedural Terminology (CPT) coding was used to distinguish cohorts of patients who had osteoarthritis of the knee and underwent UCTKA. Patients readmitted within 90 days were classified as the study population, while those who were not readmitted were classified as control. A linear regression model was utilized to analyze readmission risk factors. RESULTS: The query yielded 14,575 patients, with 986 (6.8%) being readmitted. Patient demographics such as age (P < 0.0001), sex (P < 0.009), and comorbidity (P < 0.0001) were associated with annual 90-day readmission. Patient-specific risk factors associated with 90-day readmission following press-fit total knee arthroplasty were: arrhythmia (OR: 1.29, 95% CI: 1.11-1.49, P < 0.0005), coagulopathy (OR: 1.36, 95% CI: 1.13-1.63, P < 0.0007), fluid and electrolyte abnormalities (OR: 1.59, 95% CI: 1.38-1.84, P < 0.0001), iron deficiency anemia (OR: 1.49, 95% CI: 1.27-1.73, P < 0.0001), and obesity (OR: 1.37, 95% CI: 1.18-1.60, P < 0.0001). DISCUSSION: This study demonstrates that patients with comorbidities, such as fluid and electrolyte problems, iron deficiency anemia, and obesity, were at an increased risk of readmission after having an uncemented total knee replacement. The risks of readmission following an uncemented total knee arthroplasty can be discussed with patients who have certain comorbidities by arthroplasty surgeons.

Comparison of baseline demographics and risk factors for aseptic loosening following primary total elbow arthroplasty.

BACKGROUND: Aseptic loosening is a feared complication following total elbow arthroplasty (TEA); however, literature regarding factors that may contribute to this complication is limited. The aims of this investigation were to: (1) compare baseline demographics of patients who developed aseptic loosening following primary TEA; and (2) identify patient-specific risk factors for the development of loosening. METHODS: Retrospective analysis using a nationwide claims database was performed to identify patients who underwent primary TEA and developed aseptic loosening within 2 years (study n = 307, control n = 10,741). Multivariate regression analysis generated odds ratio (OR), 95% confidence interval (95% CI), and p-value of risk factors. p < 0.05 was considered statistically significant. RESULTS: Patients who developed aseptic loosening had significant differences in numerous demographics, including age (p = 0.0001), sex (p = 0.0251), and various comorbid conditions such as obesity (15.96% vs. 8.36%, p < 0.0001). Furthermore, the risk factors most associated with aseptic loosening were obesity (OR 1.65, 95% CI 1.18-2.28, p = 0.002), male sex (OR 1.51, 95% CI 1.13-2.00, p = 0.004), and concomitant opioid use disorder (OR 1.58, 95% CI 1.14-2.15, p = 0.004). DISCUSSION: This study is the first to identify demographics and patient-related risk factors associated with aseptic loosening following primary TEA. This evidence could be applied to the clinical setting in order to educate at-risk patients of this potential complication as well as inform their post-operative clinical management. LEVEL OF EVIDENCE: Level III: Prognostic.

Combined Meniscus Repair and Anterior Cruciate Ligament Reconstruction.

Meniscal tear patterns associated with anterior cruciate ligament (ACL) tears, such as root tears and ramp lesions are common but less easily recognized on magnetic resonance imaging (MRI) compared with a complete radial tear or a locked bucket-handle tear. Timely treatment of these tears improves outcomes in the setting of ACL reconstruction. While physical examination does not enable a definitive diagnosis of meniscal root tears and ramp lesions, high-grade laxity, including a 3+ Lachman and 3+ pivot shift, should raise suspicions for these tear patterns. MRI allows visualization of both root tears and ramp lesions, although the gold standard for diagnosis is probing at the time of arthroscopy due to a high false-negative rate on MRI. Up to 17% of patients with an ACL tear have a lateral meniscal root tear; a contact mechanism and increased posterior slope are both associated with a greater incidence of lateral meniscal root tears and these are repaired with a tunnel technique. Meniscal ramp lesions occur in up to 41% of patients with ACL tears due to a contact mechanism, and we prefer repair with an inside-out technique. More than 60% of complete radial meniscal tears occur in the setting of ACL tears and are preferentially repaired with a hashtag technique for minimally separated tears and a 2-tunnel technique combined with an inside-out repair for more severe tears. Bucket-handle tears are more common in the setting of chronic ACL deficiency; concurrent with ACL reconstruction urgent meniscal repair with an inside-out technique is the gold standard, which allows for precise approximation of the tear with multiple points of fixation for improved biomechanical performance. It is critical to identify and treat these tears during ACL reconstruction because of their role as secondary stabilizers and for long-term chondral protection.

Being red, blue and green: the genetic basis of coloration differences in the strawberry poison frog (Oophaga pumilio).

BACKGROUND: Animal coloration is usually an adaptive attribute, under strong local selection pressures and often diversified among species or populations. The strawberry poison frog (Oophaga pumilio) shows an impressive array of color morphs across its distribution in Central America. Here we quantify gene expression and genetic variation to identify candidate genes involved in generating divergence in coloration between populations of red, green and blue O. pumilio from the Bocas del Toro archipelago in Panama. RESULTS: We generated a high quality non-redundant reference transcriptome by mapping the products of genome-guided and de novo transcriptome assemblies onto a re-scaffolded draft genome of O. pumilio. We then measured gene expression in individuals of the three color phenotypes and identified color-associated candidate genes by comparing differential expression results against a list of a priori gene sets for five different functional categories of coloration - pteridine synthesis, carotenoid synthesis, melanin synthesis, iridophore pathways (structural coloration), and chromatophore development. We found 68 candidate coloration loci with significant expression differences among the color phenotypes. Notable upregulated examples include pteridine synthesis genes spr, xdh and pts (in red and green frogs); carotenoid metabolism genes bco2 (in blue frogs), scarb1 (in red frogs), and guanine metabolism gene psat1 (in blue frogs). We detected significantly higher expression of the pteridine synthesis gene set in red and green frogs versus blue frogs. In addition to gene expression differences, we identified 370 outlier SNPs on 162 annotated genes showing signatures of diversifying selection, including eight pigmentation-associated genes. CONCLUSIONS: Gene expression in the skin of the three populations of frogs with differing coloration is highly divergent. The strong signal of differential expression in pteridine genes is consistent with a major role of these genes in generating the coloration differences among the three morphs. However, the finding of differentially expressed genes across pathways and functional categories suggests that multiple mechanisms are responsible for the coloration differences, likely involving both pigmentary and structural coloration. In addition to regulatory differences, we found potential evidence of differential selection acting at the protein sequence level in several color-associated loci, which could contribute to the color polymorphism.

The impact of gender and institutional factors on depression and suicidality in urology residents.

INTRODUCTION Surgical trainees experience high rates of depression and suicidal ideation (SI). However, there remain a gap in knowledge on the drivers of depression and SI in trainees, especially within the field of urology. MATERIALS AND METHODS: We conducted a national study of urology trainees using a 50-item questionnaire in May 2018. The survey included demographic, depression (Patient Health Questionnaire-9 (PHQ-9)), burnout (Maslach Burnout Inventory (MBI)), and quality of life (QoL) questions. RESULTS: Overall, 37 (17.6%) endorsed depression; 24 residents endorsed SI (11%). SI was higher in those with depression (p < 0.001). Burnout was also higher among depressed residents (97.3% versus 61.8%, p < 0.001) and those endorsing SI (16.1% versus 1.5%, p < 0.001). Depression was associated with female gender (29.2% versus 12.4%, p = 0.005), fatigue (29.5% versus 7.8%, p < 0.001), and lack of structured mentorship (23.7% versus 9.8%, p = 0.010). Access to mental health services was protective (p = 0.016). Older age, low QoL, dissatisfaction with work-life-balance (WLB), and fatigue were associated with SI. On adjusted analysis, gender (OR 3.1 [95%CI 1.4-6.9], p = 0.006), fatigue (OR 3.8[95%CI 1.6-9.0], p = 0.002), and burnout (OR 16.7 [95%CI 2.2-127.5], p = 0.007) increased the odds of depression. On exploratory analysis, self-reported burnout alone was predictive of SI (OR 7.6 [95%CI 2.5-23]), and performed similarly to an adjusted model (AUC Area 0.718 [95%CI 0.634-0.802] versus 0.825 [0.753-0.897]). CONCLUSIONS: Urology trainees experience high rates of depression and SI. Female residents have significantly higher risk of depression. A single-item appears useful to screen for SI. Further investigation is needed to understand and promote urology resident wellness.

Locality, time and heterozygosity affect chytrid infection in yellow-bellied toads.

The chytrid fungus Batrachochytrium dendrobatidis (Bd) infects numerous amphibian species worldwide and is suggested to drive population declines and extinction events. We report a study of Bd infection at the northernmost distribution of the European yellow-bellied toad Bombina variegata. A total of 577 individuals from ponds in 16 study sites were sampled for DNA and Bd throughout the breeding season. Microsatellite genotyping revealed 3 genetic clusters for the host B. variegata with an overall low genetic diversity. One of the clusters displayed a low microsatellite heterozygosity, a high inbreeding coefficient as well as high Bd infection prevalence and intensities. Multi-model estimates identified site, time of sampling, and heterozygosity to be important predictors of an individual's Bd infection status, and identified a strong effect of site on individual Bd infection intensity. The study site effects are suggestive of localized infection peaks, and the increase of individual Bd infection probabilities towards the end of the sampling period suggests cumulative infection during the breeding season. This study highlights the need for regular monitoring of Bd infection variables at multiple localities and times to gain insights into Bd dynamics. Due to the detected relationship between individual Bd infection status and heterozygosity, conservation measures should focus on the maintenance of high genetic diversity and connectivity within and among amphibian populations.