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Fournier's gangrene represents a true urologic emergency, potentially resulting in multi-organ failure and frank septic shock. Immediate administration of intravenous antibiotics and debridement of infected tissue are essential to patient survival. The authors describe their clinical approach to treatment and postoperative care of males presenting with this condition and discuss practical techniques for penile and scrotal reconstruction. [ABSTRACT FROM AUTHOR]

Introduction: The joint Canadian Infectious Diseases Society and Canadian Thoracic Society guidelines for community-acquired pneumonia (CAP) recommend 48-72 hour telephone follow-up of patients discharged from the emergency department (ED). The guidelines provide no evidence supporting this practice, and neither the clinical utility nor the effectiveness of such recommendations has been assessed. Our objective was to assess the utility of a 48-72 hour telephone follow-up protocol for patients discharged from the ED with CAP.Methods: This was a retrospective chart audit covering a 2-year period (Jan. 3, 1999 to Jan. 3, 2001) after the introduction of a clinical practice guideline (CPG) that included routine 48-72 hour telephone follow-up of patients discharged from the ED with CAP. Eligible patients were identified in the ED database, rates of referral for telephone follow-up were recorded, and 30-day outcomes (death and readmission) for patients referred versus not referred were compared.Results: During the study period, 867 patients were identified as being eligible for the study. The mean age was 55.7 years (range 16-98 yr), and mean pneumonia severity index (PSI) was 68.9 (range 6-187). Despite the CPG, only 148 patients (17.1%) were referred for telephone follow-up. Age, demographics, comorbidity, clinical status and pneumonia severity were similar for referred and non-referred patients. Thirty-day death (2.5%) and readmission rates (3%) were strongly related to PSI score, but did not differ significantly in the 2 comparison groups.Conclusion: In this setting, physicians were poorly compliant with a routine telephone follow-up protocol. The likelihood of referral for follow-up did not correlate with pneumonia severity, and follow-up referral did not appear to affect patient outcome. These findings do not support recommendations for routine early follow-up mechanisms beyond those already existing in the community. [ABSTRACT FROM AUTHOR]

Background: Current studies assessing the change in pelvic tilt for ambulatory patients with cerebral palsy (CP) after surgical hamstring lengthening (SHL) lack a comparison cohort without prior SHL and are limited to younger patients. This study presents gait data of middle-aged adults with CP, primarily focusing on the pelvis, and compares pelvic tilt, trunk tilt, and knee flexion between those with and without prior SHL., Materials and Methods: A consecutive series of 54 adults with CP, a mean age of 36±13 years, and Gross Motor Function Classification System (GMFCS) levels I-III were included. Thirty-two (59%) had SHL performed at a mean age of 8±5 years. Three-dimensional gait analysis data prospectively collected at a mean of 28±14 years postoperatively were retrospectively analyzed. Chi-square tests were used to compare demographic and surgical history data and statistical parameter mapping was used to compare knee flexion during stance and pelvic and trunk tilts during the gait cycle between SHL and SHL-naive groups., Results: Age, GMFCS level, sex, race, topography, and ethnicity were not different between the groups ( P =.217-.612). Anterior pelvic tilt throughout gait was significantly greater in the SHL group compared with the SHL-naive group (63%-87%; P =.033). This difference was augmented after accounting for other surgical history and revision SHL (0%-32%, P =.019; and 46%-93%, P =.007)., Conclusion: Within a cohort of adults with CP, GMFCS levels I-III, and a mean age of 36 years, those with a history of SHL, performed a mean of 28 years prior to 3-dimensional gait analysis, walked with increased anterior pelvic tilt compared with those without a history of SHL. [ Orthopedics . 2024;47(5):270-275.].

Background: Developmental hip dysplasia (DDH) is a common condition associated with pain, disability and early hip osteoarthritis when untreated. Health utility scores have not previously been defined for a comprehensive set of DDH health states. The purpose of this study was to establish utility scores associated with DDH health states., Methods: Patients treated for DDH using either Pavlik harness or abduction bracing and closed/open hip reduction between February 2016 and March 2023 were identified. Thirteen vignettes describing health states in the DDH life cycle were developed. Parents of patients were asked to score each state from 0 to 100 using the feeling thermometer. A score of "0" represents the worst state imaginable/death and a score of "100" represents perfect health. Utility scores were calculated and compared between parents of patients treated operatively and nonoperatively., Results: Ninety parents of children with DDH (45 operative, 45 nonoperative) were enrolled. There were 82 (91.1%) female children (median age of 4.9 years at enrollment). Median utility scores ranged from 77.5 [interquartile range (IQR): 70.0 to 90.0] for Pavlik harness and 80.0 (IQR: 60.0 to 86.3) for abduction bracing to 40.0 (IQR: 20.0 to 60.0) for reduction/spica cast and 40.0 (IQR: 20.0 to 50.0) for end-stage hip arthritis. Utility scores were lower in the operative group for Pavlik harness (median 70.0 vs. 80.0, P<0.01), end-stage arthritis (30.0 vs. 40.0, P=0.04), and 1 year after total hip arthroplasty (85.0 vs. 90.0, P=0.03) health states compared with the nonoperative group. There were no differences in other scores., Conclusions: Thirteen health states related to the life cycle of DDH were collected. Nonoperative interventions for DDH were viewed by parents slightly more favorably than operative treatments or long-term sequelae of untreated DDH. Future studies can assess other potential treatment experiences for patients with DDH or use these scores to perform cost-effectiveness analysis of different screening techniques for DDH., Level of Evidence: Level III., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Spondylolysis is common in athletes participating in gymnastics, football, dance, and weightlifting. Few studies have reviewed return to sports (RTS) rates in young athletes after surgical intervention for spondylolysis., Purposes: We sought to review the literature on RTS frequencies and timing, as well as postoperative treatment, in children and adolescents who underwent spondylolysis surgery., Methods: This was a systematic review, using the PubMed, Embase, and Cochrane databases, of primary, peer-reviewed studies published from 2014 to 2022 that investigated child and adolescent RTS after spondylolysis surgery. Each author independently reviewed each study's design, number of participants, age range, fixation, postoperative course of treatment, frequency of RTS, and reasons for failure of RTS., Results: The initial search produced 106 articles; 25 were reviewed in full and 9 were included in the final analysis, with a combined total of 177 patients. Sample sizes ranged from 5 to 52 participants. The most common fixations were direct repair (6 studies, n = 120), indirect repair (3 studies, n = 22), and fusion (2 studies, n = 35). Five studies mentioned the use of immediate postoperative immobilization. Physical therapy programs were initiated most often at 6 weeks postoperatively. The RTS rate of the 177 athletes (median age younger than 23 years) was 76% to 100%. The most common reason for failure to RTS was lower back pain., Conclusions: This systematic review suggests that young athletes RTS at a high rate following spondylolysis surgery, but more rigorous study is warranted. The review also found varied preferred fixation methodologies and postoperative treatment regimens across the available studies., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Background: Anterior knee pain is a common reason for referral to a pediatric orthopedic surgeon. Although previous studies have found that adults with anatomic risk factors for patellofemoral instability (patella dislocation) are predisposed to anterior knee pain, no studies have elucidated the relationship between anatomic risk factors for patellofemoral instability and anterior knee pain in children. Purpose : We sought to characterize common radiographic findings in adolescent patients with a chief complaint of anterior knee pain and to determine the prevalence of abnormal patellofemoral morphology. Methods : We conducted a retrospective review of patients 13 to 18 years old with anterior knee pain at a single tertiary care metropolitan institution from 2016 to 2021. X-rays and magnetic resonance imaging (MRI) were evaluated in those diagnosed with "chondromalacia patellae," "chondromalacia," "patellofemoral disorders," or "anterior knee pain." Patella alta, tibial tubercle-trochlear groove (TT-TG) distance, tubercle height, Wiberg patella type, patellar tilt, and trochlear dysplasia characterization were recorded. Results : Of the 293 adolescents with anterior knee pain included, 62 had bilateral anterior knee pain. Of the 172 MRIs, 72 (42%) met criteria for patella alta, Caton-Deschamps Index (CDI) >1.3, 35% had a TT-TG distance >15 mm, and 32% had lateral patellar tilt >15°. Magnetic resonance imaging findings included infrapatellar fat pad signal hyperintensity (41%) and patellofemoral dysplasia (23%). Of all 293 adolescents, 74% had images showing abnormal patellofemoral morphology, of which 30% had a history of 1 or more patellar dislocation. Overall, 40% of the adolescents had surgery, most commonly medial patellofemoral ligament (MPFL) reconstruction (18%). Conclusions : In this retrospective review, nearly 3/4 of adolescents with anterior knee pain had images showing abnormal patellofemoral morphology, including patella alta, increased TT-TG distance, trochlear dysplasia, or abnormal lateral patellar tilt; only 18% had MPFL surgery. These findings suggest that primary care providers might consider obtaining X-rays and/or MRIs to evaluate for pathology that warrants orthopedic evaluation., Competing Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: S.M.S., MD, reports relationships with Organogenesis, Moximed, Smith & Nephew, Vericel, American Journal of Sports Medicine, Arthroscopy Association of North America, Engage, Stryker, and JRF Ortho. The other authors declared no potential conflicts of interest., (© The Author(s) 2024.)

Background: Compared with male senior authors, female senior authors publish less often in orthopedic journals than expected based on their population proportion. It is unknown whether this trend is also present among orthopedic trainees. Purpose : We sought to determine whether there is a gender discrepancy in the publication volume and authorship status among orthopedic residents. Methods : We conducted a cross-sectional analysis to evaluate the research productivity of male and female orthopedic residents. The top 10 ranked US orthopedic surgery residencies by research output in 2021-2022 were obtained from Doximity. Residents' names were recorded from each institution's residency website. We classified each resident as male or female, searched on PubMed, and recorded the number of publications relevant to orthopedic surgery. Resident contribution to each publication was recorded as either a first/last author or a middle author. To assess contributions by postgraduate year, we compared male and female junior residents (PGY1-3) and senior residents (PGY4-5) using the number of total publications, middle author publications, first/last author publications, and the difference between the number of middle and first/last author publications. Results : Among the 335 male and 117 female residents included, male residents had more total publications than female residents. Among PGY4-5, male residents had more total publications and middle author publications. There was no difference in the number of first/last author publications between male and female PGY4-5 residents. Conclusions : Our cross-sectional analysis found that in the 2021-2022 academic year, male orthopedic surgery residents published more often than female residents, although among PGY4-5 residents, we found no gender differences in number of first/last author publications. The difference in total publications among PGY4-5 residents is likely due to differences in middle author publications. Future research should consider residents' self-identified gender, including non-binary and gender-fluid identity., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2023.)

Background: The Pavlik harness has been used for approximately a century to treat developmental dysplasia of the hip (DDH). Femoral nerve palsy is a documented complication of Pavlik harness use, with an incidence ranging from 2.5% to 11.2%. Rare reports of brachial plexus palsy have also been documented. The primary purpose of the current study was to evaluate the incidence of various nerve palsies in patients undergoing Pavlik harness treatment for DDH. Secondary aims were to identify patient demographic or hip characteristics associated with nerve palsy., Methods: We performed a retrospective review of patients diagnosed with DDH and treated with a Pavlik harness from February 1, 2016, to April 1, 2023, at a single tertiary care orthopaedic hospital. Hip laterality, use of a subsequent rigid abduction orthosis, birth order, breech positioning, weight, and family history were collected. The median (and interquartile range [IQR]) or mean (and standard deviation [SD]) were reported for all continuous variables. Independent 2-sample t tests and Mann-Whitney U tests were conducted to identify associations between the variables collected at the initiation of Pavlik harness treatment and the occurrence of nerve palsy., Results: Three hundred and fifty-one patients (547 hips) were included. Twenty-two cases of femoral nerve palsy (4% of all treated hips), 1 case of inferior gluteal nerve palsy (0.18%), and 2 cases of brachial plexus palsy (0.37%) were diagnosed. Patients with nerve palsy had more severe DDH as measured by the Graf classification (p < 0.001) and more severe DDH as measured on physical examination via the Barlow and Ortolani maneuvers (p = 0.003)., Conclusions: Nerve palsies were associated with more severe DDH at the initiation of Pavlik harness use. Upper and lower-extremity neurological status should be scrutinized at initiation and throughout treatment to assess for nerve palsies. The potential for femoral, gluteal, and brachial plexus palsies should be included in the discussion of risks at the beginning of treatment. Families may be reassured that nerve palsies associated with Pavlik harness can be expected to resolve with a short break from treatment., Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: No external funding was received for this work. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJS/H864)., (Copyright © 2024 by The Journal of Bone and Joint Surgery, Incorporated.)

Purpose of Review: The treatment of many distal radius fractures has shifted from casting to splinting or the application of a soft dressing. This review includes a review of the types of pediatric distal radius fractures and the most recent literature on the management of these injuries., Recent Findings: Many nondisplaced distal radius fractures may be treated with removable splints or bandages. This mitigates complications with cast immobilization. Additionally, many of these injuries do not require follow-up treatment and thereby reduce healthcare costs., Summary: This update on distal radius fractures in the pediatric population highlights changes in the treatment paradigm and demonstrates an opportunity to diminish healthcare costs., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Hsp90 and Hsp70 are highly conserved molecular chaperones that help maintain proteostasis by participating in protein folding, unfolding, remodeling and activation of proteins. Both chaperones are also important for cellular recovery following environmental stresses. Hsp90 and Hsp70 function collaboratively for the remodeling and activation of some client proteins. Previous studies using E. coli and S. cerevisiae showed that residues in the Hsp90 middle domain directly interact with a region in the Hsp70 nucleotide binding domain, in the same region known to bind J-domain proteins. Importantly, J-domain proteins facilitate and stabilize the interaction between Hsp90 and Hsp70 both in E. coli and S. cerevisiae. To further explore the role of J-domain proteins in protein reactivation, we tested the hypothesis that J-domain proteins participate in the collaboration between Hsp90 and Hsp70 by simultaneously interacting with Hsp90 and Hsp70. Using E. coli Hsp90, Hsp70 (DnaK), and a J-domain protein (CbpA), we detected a ternary complex containing all three proteins. The interaction involved the J-domain of CbpA, the DnaK binding region of E. coli Hsp90, and the J-domain protein binding region of DnaK where Hsp90 also binds. Additionally, results show that E. coli Hsp90 interacts with E. coli J-domain proteins, DnaJ and CbpA, and that yeast Hsp90, Hsp82, interacts with a yeast J-domain protein, Ydj1. Together these results suggest that the complexes may be transient intermediates in the pathway of collaborative protein remodeling by Hsp90 and Hsp70., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background: With the rise of social media and other web-based platforms, there has been a shift in how medical research findings are disseminated. Questions/Purposes : We sought to investigate how often orthopedic surgeons use different knowledge-seeking methods and how confident they were in their ability to stay up-to-date. Methods : We distributed a 23-question survey to 120 orthopedic surgeons employed at a single tertiary-care metropolitan orthopedic hospital. The survey collected the surgeons' use of reference managers, RSS feeds, and preferred methods of staying up-to-date. Respondents were asked to report the number of hours they spent staying up-to-date per week and their success with keeping up with orthopedic specialty literature. Results : A total of 85 physicians responded (median age, 52 years); 83% of respondents who spent 3 or more hours a week in keeping up-to-date with the literature said they felt successful in doing so, while 40% of participants who spent less than 1 hour a week said they felt successful. Fifty-five percent of surgeons under the median age used social media, while only 29% of surgeons over the median age used social media. Conclusions : This survey suggests that spending only 1 to 2 hours per week was enough to make the orthopedic surgeons we surveyed feel confident that they were keeping up with the literature in their specialty. These findings also suggest that it may be more important for surgeons to choose a convenient method of literature review that will enable them to maximize time spent reading, rather than attempting to use any one source., Competing Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Peter D. Fabricant, MD, MPH, reports relationships with WishBone, Osso VR, and Pediatric Orthopaedic Society of North America (POSNA). The other authors report no potential conflicts of interest., (© The Author(s) 2022.)

Purpose of Review: The purpose of this review is to outline the most recent understanding of torticollis in the pediatric population., Recent Findings: It is important to diagnose the underlying condition of torticollis early in childhood, as some conditions that cause torticollis may result in major developmental delays in early motor milestones. Recent studies have highlighted that many of the rarer causes of torticollis are often misdiagnosed as congenital muscular torticollis, suggesting that physicians should pay close attention to the results of clinical and radiographic examinations when patients present with torticollis., Summary: Congenital muscular torticollis is the most common cause of torticollis. Other, less common causes of torticollis include vertebral abnormalities, ocular torticollis, gastrointestinal disorders, soft tissue infections of the neck, posterior fossa tumors, and benign paroxysmal torticollis. Although rare, these differential diagnoses should be considered during a clinical work-up for a patient who presents with torticollis., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Supracondylar humerus (SCH) fractures are common pediatric injuries, typically requiring closed reduction and percutaneous pinning or open reduction. These injuries are managed frequently by both pediatric-trained (PTOS) and nonpediatric-trained (NTOS) orthopaedic surgeons. However, some literature suggests that complications for pediatric injuries are lower when managed by PTOS. Therefore, this meta-analysis sought to compile existing literature comparing patients treated by PTOS and NTOS to better understand differences in management and clinical outcomes., Methods: Using preferred reporting items for systematic reviews and meta-analyses (PRISMA) methodology, a systematic review was conducted for all articles comparing SCH fractures managed by PTOS and NTOS in 4 online databases (PubMed, Embase, CINAHL, Cochrane). Study quality was assessed through the use of the Newcastle-Ottawa Scale. Meta-analyses were then performed for postoperative outcomes using pooled data from the included studies. Statistics were reported as odds ratios and 95% CI., Results: This search strategy yielded 242 unique titles, of which 12 underwent full-text review and 7 met final inclusion. All studies were retrospective and evaluated patients treated in the United States. There were a total of 692 and 769 patients treated by PTOS and NTOS, respectively. PTOS had shorter operative times [mean difference, 13.6 min (CI, -23.9 to -3.4), P=0.01] and less frequently utilized a medial-entry pin [odds ratios, 0.36 (CI, 0.2 to 0.9), P=0.03]. There were no differences in time to treatment, the necessity of open reduction, postoperative Baumann angle, or complications including surgical site infection or iatrogenic nerve injury., Conclusions: Despite shorter operative times and lower frequency of cross-pinning when treated by PTOS, pediatric SCH fracture outcomes are similar when treated by PTOS and NTOS. These findings demonstrate that these fractures may possibly be treated safely by both PTOS and experienced fellowship-trained academic NTOS who are comfortable managing these injuries in pediatric patients., Level of Evidence: Level III; Meta-analysis., Competing Interests: P.D.F.: Clinical Orthopaedics and Related Research: Editorial or Governing board. Pediatric Orthopaedic Society of North America: Board or committee member. Osso VR: Stock or stock options. WishBone Orthopaedics: Paid consultant. Research in Osteochondritis of the Knee (ROCK): Board or committee member. The remaining authors declare no conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Mixing alcohol with caffeinated energy drinks is a common practice among young people. Consumption of alcohol mixed in energy drink is associated with increased risk of binge drinking and alcohol dependence. The purpose of this study was to determine whether voluntary intermittent access to alcohol mixed in energy drink in adolescent rats alters adult self-administration of alcohol, anxiety, and memory., Methods: For 10 weeks in the home-cage, two groups of adolescent female Sprague-Dawley rats had intermittent access to energy drink (ED) or 10% alcohol mixed in energy drink (AmED) with water concurrently available. Other rat groups had daily continuous access to ED or AmED. Anxiety was measured with an open field test and memory was assessed with a novel place recognition test. For self-administration, rats pressed levers for 10% alcohol alone on a fixed ratio (FR1) and on a progressive ratio (PR)., Results: Intermittent access to AmED generated greater intake during the initial 30 min of access (AmED 1.70 ± 0.04 g/kg vs. ED 1.01 ± 0.06 g/kg) and during the subsequent 24 h (AmED 7.04 ± 0.25 g/kg vs. ED 5.60 ± 0.29 g/kg). Intermittent AmED caused a significant but small decrease in anxiety while neither ED nor AmED altered memory. During alcohol self-administration, group differences emerged only during PR testing during which intermittent AmED rats responded more than all other groups., Conclusions: These findings suggest that intermittent access to AmED generates binge-like consumption that supports human findings that AmED generates greater alcohol consumption. Furthermore, experience with AmED may alter the motivational properties of alcohol into adulthood without necessarily causing a major impact on anxiety or memory., (© 2022 Research Society on Alcoholism.)

Background: The cost of cancer care is high and rising. Evidence of increased patient cost burden is prevalent in the medical literature and has been defined as "financial toxicity," the financial hardship and financial concerns experienced by patients because of a disease and its related treatments. With targeted therapies and growing out-of-pocket costs, patient financial toxicity is a growing concern among patients with gynecologic cancer., Objective: This study aimed to determine the prevalence of financial toxicity and identify its risk factors in patients with gynecologic cancer treated at a large cancer center using objective data., Study Design: Using institutional databases, we identified patients with gynecologic cancer treated from January 2016 to December 2018. Patients with a preinvasive disease were excluded. Financial toxicity was defined according to institutionally derived metrics as the presence of ≥1 of the following: ≥2 bills sent to collections, application or granting of a payment plan, settlement, bankruptcy, financial assistance program enrollment, or a finance-related social work visit. Clinical characteristics were gathered using a 2-year look-back from the time of the first financial toxicity event or a randomly selected treatment date for those not experiencing toxicity. Risk factors were assessed using chi-squared tests. All significant variables on univariate analysis were included in the logistic regression model., Results: Of the 4655 patients included in the analysis, 1155 (25%) experienced financial toxicity. In the univariate analysis, cervical cancer (35%), stage 3 or 4 disease (24% and 30%, respectively), younger age (35% for age <30 years), nonpartnered marital status (31%), Black (45%) or Hispanic (37%) race and ethnicity, self-pay (48%) or commercial insurance (30%), clinical trial participation (31%), more imaging studies (39% for ≥9), ≥1 emergency department visit (36%), longer inpatient stays (36% for ≥20 days), and more outpatient clinician visits (41% for ≥20 visits) were significantly associated with financial toxicity (P<.01). In multivariate analysis, younger age, nonpartnered marital status, Black and Hispanic race and ethnicity, commercial insurance, more imaging studies, and more outpatient physician visits were significantly associated with financial toxicity., Conclusion: Financial toxicity is an increasing problem for patients with gynecologic cancer. Our analysis, using objective measures of financial toxicity, has suggested that demographic factors and healthcare utilization metrics may be used to proactively identify at-risk patients for financial toxicity., (Copyright © 2021 Elsevier Inc. All rights reserved.)

In July 2016, a severe coral reef invertebrate mortality event occurred approximately 200 km southeast of Galveston, Texas, at the East Flower Garden Bank, wherein ∼82% of corals in a 0.06-km 2 area died. Based on surveys of dead corals and other invertebrates shortly after this mortality event, responders hypothesized that localized hypoxia was the most likely direct cause. However, no dissolved oxygen data were available to test this hypothesis, because oxygen is not continuously monitored within the Flower Garden Banks sanctuary. Here, we quantify microbial plankton community diversity based on four cruises over 2 years at the Flower Garden Banks, including a cruise just 5 to 8 days after the mortality event was first observed. In contrast with observations collected during nonmortality conditions, microbial plankton communities in the thermocline were differentially enriched with taxa known to be active and abundant in oxygen minimum zones or that have known adaptations to oxygen limitation shortly after the mortality event (e.g., SAR324, Thioglobaceae , Nitrosopelagicus , and Thermoplasmata MGII). Unexpectedly, these enrichments were not localized to the East Bank but were instead prevalent across the entire study area, suggesting there was a widespread depletion of dissolved oxygen concentrations in the thermocline around the time of the mortality event. Hydrographic analysis revealed the southern East Bank coral reef (where the localized mortality event occurred) was uniquely within the thermocline at this time. Our results demonstrate how temporal monitoring of microbial communities can be a useful tool to address questions related to past environmental events. IMPORTANCE In the northwestern Gulf of Mexico in July 2016, ∼82% of corals in a small area of the East Flower Garden Bank coral reef suddenly died without warning. Oxygen depletion is believed to have been the cause. However, there was considerable uncertainty, as no oxygen data were available from the time of the event. Microbes are sensitive to changes in oxygen and can be used as bioindicators of oxygen loss. In this study, we analyze microbial communities in water samples collected over several years at the Flower Garden Banks, including shortly after the mortality event. Our findings indicate that compared to normal conditions, oxygen depletion was widespread in the deep-water layer during the mortality event. Hydrographic analysis of water masses further revealed some of this low-oxygen water likely upwelled onto the coral reef.

Marine microbial communities play an important role in biodegradation of subsurface plumes of oil that form after oil is accidentally released from a seafloor wellhead. The response of these mesopelagic microbial communities to the application of chemical dispersants following oil spills remains a debated topic. While there is evidence that contrasting results in some previous work may be due to differences in dosage between studies, the impacts of these differences on mesopelagic microbial community composition remains unconstrained. To answer this open question, we exposed a mesopelagic microbial community from the Gulf of Mexico to oil alone, three concentrations of oil dispersed with Corexit 9500, and three concentrations of Corexit 9500 alone over long periods of time. We analyzed changes in hydrocarbon chemistry, cell abundance, and microbial community composition at zero, three and six weeks. The lowest concentration of dispersed oil yielded hydrocarbon concentrations lower than oil alone and microbial community composition more similar to control seawater than any other treatments with oil or dispersant. Higher concentrations of dispersed oil resulted in higher concentrations of microbe-oil microaggregates and similar microbial composition to the oil alone treatment. The genus Colwellia was more abundant when exposed to multiple concentrations of dispersed oil, but not when exposed to dispersant alone. Conversely, the most abundant Marinobacter amplicon sequence variant (ASV) was not influenced by dispersant when oil was present and showed an inverse relationship to the summed abundance of Alcanivorax ASVs. As a whole, the data presented here show that the concentration of oil strongly impacts microbial community response, more so than the presence of dispersant, confirming the importance of the concentrations of both oil and dispersant in considering the design and interpretation of results for oil spill simulation experiments., Competing Interests: The authors have declared that no competing interests exist.

Purpose of Review: Acute ankle sprains frequently occur in active children and adolescents but may be the initial clinical presentation of other less common disorders affecting the lower extremities. There are many conditions that may cause one or multiple episodes of ankle injury that are misdiagnosed as an acute ankle sprain. This manuscript highlights diagnoses that should be considered when evaluating and managing a child or adolescent who presents initially and/or repeatedly with an acute ankle sprain., Recent Findings: In recent years, various studies have continued to note the prevalence of misdiagnosed ankle sprains, especially amongst the paediatric population. If ankle radiographs demonstrate no abnormalities during an initial clinical examination, often the patient is diagnosed with an acute ankle sprain. However, this can be a misdiagnosis, especially when the patient has had recurrent episodes of ankle injury and ancillary studies are not performed., Summary: There are many diagnoses that can go unnoticed in the initial evaluation of a paediatric or adolescent ankle sprain. It is important for physicians to be aware of these other conditions to ensure proper treatment plans. This manuscript will analyse five conditions that may be misdiagnosed as an ankle sprain, including juvenile idiopathic arthritis, osteochondritis dissecans of the talus, hereditary sensory motor neuropathy (Charcot-Marie Tooth disease), tarsal coalition and transitional ankle fractures., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

As the outermost layer of plants, the epidermis serves as a critical interface between plants and the environment. During leaf development, the differentiation of specialized epidermal cell types, including stomatal guard cells, pavement cells, and trichomes, occurs simultaneously, each providing unique and pivotal functions for plant growth and survival. Decades of molecular-genetic and physiological studies have unraveled key players and hormone signaling specifying epidermal differentiation. However, most studies focus on only one cell type at a time, and how these distinct cell types coordinate as a unit is far from well-comprehended. Here we provide a review on the current knowledge of regulatory mechanisms underpinning the fate specification, differentiation, morphogenesis, and positioning of these specialized cell types. Emphasis is given to their shared developmental origins, fate flexibility, as well as cell cycle and hormonal controls. Furthermore, we discuss computational modeling approaches to integrate how mechanical properties of individual epidermal cell types and entire tissue/organ properties mutually influence each other. We hope to illuminate the underlying mechanisms coordinating the cell differentiation that ultimately generate a functional leaf epidermis., (© American Society of Plant Biologists 2021. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Following oil spills in aquatic environments, oil-associated flocculants observed within contaminated waters ultimately lead to the sedimentation of oil as marine oil snow (MOS). To better understand the role of aggregates in hydrocarbon degradation and transport, we experimentally produced a MOS sedimentation event using Gulf of Mexico coastal waters amended with oil or oil plus dispersant. In addition to the formation of MOS, smaller micrometer-scale (10- to 150-μm) microbial aggregates were observed. Visual inspection of these microaggregates revealed that they were most abundant in the oil-amended treatments and frequently associated with oil droplets, linking their formation to the presence of oil. The peak abundance of the microaggregates coincided with the maximum rates of biological hydrocarbon oxidation estimated by the mineralization of 14 C-labeled hexadecane and naphthalene. To elucidate the potential of microaggregates to serve as hot spots for hydrocarbon degradation, we characterized the free-living and aggregate-associated microbial assemblages using 16S rRNA gene sequencing. The microaggregate population was found to be bacterially dominated and enriched with putative hydrocarbon-degrading taxa. Direct observation of some of these taxa using catalyzed reporter deposition fluorescence in situ hybridization confirmed their greater abundance within microaggregates relative to the surrounding seawater. Metagenomic sequencing of these bacteria-oil microaggregates (BOMAs) further supported their community's capacity to utilize a wide variety of hydrocarbon compounds. Taken together, these data highlight that BOMAs are inherent features in the biological response to oil spills and likely important hot spots for hydrocarbon oxidation in the ocean. IMPORTANCE Vast quantities of oil-associated marine snow (MOS) formed in the water column as part of the natural biological response to the Deepwater Horizon drilling accident. Despite the scale of the event, uncertainty remains about the mechanisms controlling MOS formation and its impact on the environment. In addition to MOS, we observed micrometer-scale (10- to 150-μm) aggregates whose abundance coincided with maximum rates of hydrocarbon degradation and whose composition was dominated by hydrocarbon-degrading bacteria with the genetic potential to metabolize a range of these compounds. This targeted study examining the role of these bacteria-oil microaggregates in hydrocarbon degradation reveals details of this fundamental component of the biological response to oil spills, and with it, alterations to biogeochemical cycling in the ocean.

Background: The 5-HT 1B receptor (5-HT 1B R) agonist, CP94253, enhances cocaine intake during maintenance of self-administration (SA) but attenuates intake after 21 days of forced abstinence in male rats., Aims: We examined whether CP94253 attenuates cocaine intake in female rats after a period of abstinence, and if these attenuating effects persist or revert to enhancing cocaine intake during resumption (i.e. relapse) of daily cocaine SA., Methods: Male and female rats trained to lever press on a fixed ratio 5 schedule of cocaine reinforcement underwent ⩾21 days of forced abstinence. They were then tested for the effects of CP94253 (5.6 mg/kg, SC) or vehicle on cocaine SA. During the test session, rats had 1-h access to the training dose of cocaine (0.75 mg/kg, IV) followed by 1-h access to a lower cocaine dose (0.075 mg/kg, IV). Rats then resumed cocaine SA for 15 days to mimic relapse and were retested as done previously. Subsequently, rats underwent abstinence again (21-60 days) and were tested for CP94253 effects on locomotion and cue reactivity (i.e. responding for light/tone cues previously paired with cocaine infusions)., Results: Regardless of sex, CP94253 decreased cocaine intake after abstinence and during resumption of SA and decreased cue reactivity while having no effect on locomotion., Conclusions: CP94253 decreases cocaine intake and cocaine seeking in both males and females even after resumption of cocaine SA. These findings suggest that the inhibitory effects of CP94253 observed after abstinence are long-lasting, and therefore, 5-HT 1B R agonists may have clinical efficacy as anti-relapse medications for cocaine use disorders.

The plant hormone auxin, a master coordinator of development, regulates hypocotyl elongation during seedling growth. We previously identified the synthetic molecule RubNeddin 1 (RN1), which induces degradation of the AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) transcriptional repressors INDOLE-3-ACETIC ACID-INDUCIBLE3 (IAA3) and IAA7 in planta and strongly promotes hypocotyl elongation. In the present study, we show that despite the structural similarity of RN1 to the synthetic auxin 2,4-dichlorophenoxyacetic-acid (2,4-D), direct treatments with these compounds in Arabidopsis (Arabidopsis thaliana) result in distinct effects, possibly due to enhanced uptake of RN1 and low-level, chronic release of 2,4-D from RN1 in planta. We confirm RN1-induced hypocotyl elongation occurs via specific TRANSPORT INHIBITOR RESISTANT1 (TIR1)/AUXIN SIGNALING F-BOX (AFB) receptor-mediated auxin signaling involving TIR1, AFB2, and AFB5. Using a transcriptome profiling strategy and candidate gene approach, we identify the genes ZINC FINGER OF ARABIDOPSIS THALIANA10 (ZAT10), ARABIDOPSIS TOXICOS EN LEVADURA31 (ATL31), and WRKY DNA-BINDING PROTEIN33 (WRKY33) as being rapidly upregulated by RN1, despite being downregulated by 2,4-D treatment. RN1-induced expression of these genes also occurs via TIR1/AFB-mediated auxin signaling. Our results suggest both hypocotyl elongation and transcription of these genes are induced by RN1 via the promoted degradation of the AUX/IAA transcriptional repressor IAA7. Moreover, these three genes, which are known to be stress-related, act in an inter-dependent transcriptional regulatory network controlling hypocotyl elongation. Together, our results suggest ZAT10, ATL31, and WRKY33 take part in a common gene network regulating hypocotyl elongation in Arabidopsis downstream of a selective auxin perception module likely involving TIR1, AFB2, and AFB5 and inducing the degradation of IAA7., (© The Author(s) 2021. Published by Oxford University Press on behalf of American Society of Plant Biologists.)

The plant epidermis serves many essential functions, including interactions with the environment, protection, mechanical strength, and regulation of tissue and organ growth. To achieve these functions, specialized epidermal cells develop into particular shapes. These include the intriguing interdigitated jigsaw puzzle shape of cotyledon and leaf pavement cells seen in many species, the precise functions of which remain rather obscure. Although pavement cell shape regulation is complex and still a long way from being fully understood, the roles of the cell wall, mechanical stresses, cytoskeleton, cytoskeletal regulatory proteins, and phytohormones are becoming clearer. Here, we provide a review of this current knowledge of pavement cell morphogenesis, generated from a wealth of experimental evidence and assisted by computational modeling approaches. We also discuss the evolution and potential functions of pavement cell interdigitation. Throughout the review, we highlight some of the thought-provoking controversies and creative theories surrounding the formation of the curious puzzle shape of these cells.

In a world that will rely increasingly on efficient plant growth for sufficient food, it is important to learn about natural mechanisms of phytohormone action. In this work, the introduction of a fluorophore to an auxin molecule represents a sensitive and non-invasive method to directly visualise auxin localisation with high spatiotemporal resolution. The state-of-the-art multidisciplinary approaches of genetic and chemical biology analysis together with live cell imaging, liquid chromatography-mass spectrometry (LC-MS) and surface plasmon resonance (SPR) methods were employed for the characterisation of auxin-related biological activity, distribution and stability of the presented compounds in Arabidopsis thaliana. Despite partial metabolisation in vivo, these fluorescent auxins display an uneven and dynamic distribution leading to the formation of fluorescence maxima in tissues known to concentrate natural auxin, such as the concave side of the apical hook. Importantly, their distribution is altered in response to different exogenous stimuli in both roots and shoots. Moreover, we characterised the subcellular localisation of the fluorescent auxin analogues as being present in the endoplasmic reticulum and endosomes. Our work provides powerful tools to visualise auxin distribution within different plant tissues at cellular or subcellular levels and in response to internal and environmental stimuli during plant development., (© 2021 The Authors. New Phytologist © 2021 New Phytologist Trust.)

Purpose of Review: Adolescent and young adult hip dysplasia is a cause of hip pain which can lead to early hip osteoarthritis. This may result in early hip osteoarthrosis and possible total hip arthroplasty if dysplasia is not recognized and treated. Hip dysplasia in this population can be difficult to diagnose. It is important for primary care providers and pediatricians to recognize the symptoms, physical examination findings, and radiographic findings associated with adolescent hip dysplasia so that the patient can be referred to an orthopedist specializing in hip disorder. The current review includes the most up-to-date literature on the diagnosis of adolescent hip dysplasia., Recent Findings: Recent studies have shown that most patients presenting with symptomatic hip dysplasia present with insidious onset hip pain localized to either the groin or lateral aspect of the hip in a C-shape distribution around the inguinal crease. Patients most commonly see several different providers and have pain for a long period prior to accurate diagnosis. There are myriad radiographic measurements of hip dysplasia, many of which are described below that are helpful in initial diagnosis., Summary: Adolescent and young adult hip dysplasia can be a cause of early, progressive hip osteoarthritis. Hip dysplasia is a term that represents a spectrum of disorder due to abnormal formation of the hip joint, resulting in an acetabulum that does not sufficiently cover the femoral head. The ability to recognize symptoms, physical examination findings, and radiographic evidence of adolescent hip dysplasia is critical so that the patient can be referred to the appropriate provider and receive timely treatment prior to the onset of degenerative hip disease. This article will focus mainly on the diagnosis of adolescent hip dysplasia. The standard for treatment of acetabular dysplasia in skeletally mature patients is the periacetabular osteotomy; however, nonoperative management and occasionally arthroscopic surgery can also be considered in cases of symptomatic borderline dysplasia., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: Facebook is a popular social media platform used globally to keep connected and informed. The aims of this study were to determine the contribution of Facebook to the participation rate of young adults enrolled in a longitudinal cohort study, and to examine systematic differences in participants recruited through Facebook compared with those recruited through traditional methods., Methods: Potential participants comprised 297 consecutive survivors born extremely preterm (<28 weeks' gestation) or extremely low birth weight (<1000 g birth weight) in 1991-92 in the state of Victoria, Australia, and 260 contemporaneously recruited normal birth weight (>2499 g birth weight) controls who had participated previously in a prospective cohort study. At 25 years of age participants were approached initially via traditional methods (mail, telephone, texts), and subsequently by Facebook for those difficult to contact or locate., Results: Contact was attempted with 523 young adults via traditional methods and 49% (n = 255) agreed to participate. Of the 208 participants unable to be located or contacted via traditional methods, 153 were subsequently located via Facebook. Of these 82% (n = 125) responded promptly within a day of receiving the Facebook invite, and 41% (n = 63) ultimately participated. The participation rate increased from 49% (255 of 523) to 61% (318 of 523) with the addition of Facebook, an absolute increase of 12%. Participants recruited by Facebook were slightly older, had lower rates of school completion and lower cognitive score at 18 years of age compared with those recruited via traditional methods., Conclusions: Using Facebook improved participation of young adults enrolled in this longitudinal preterm follow up study, 25 years after original recruitment., (Copyright © 2020 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.)

Marine oil spills can impact both coastal and offshore marine environments, but little information is available on how the microbial response to oil and dispersants might differ between these biomes. Here, we describe the compositional and functional response of microbial communities to different concentrations of oil and chemically dispersed oil in coastal and offshore surface waters from the Texas-Louisiana continental shelf. Using a combination of analytical chemistry and 16S rRNA amplicon and metatranscriptomic sequencing, we provide a broad, comparative overview of the ecological response of hydrocarbon-degrading bacteria and their expression of hydrocarbon-degrading genes in marine surface waters over time between two oceanic biomes. We found evidence for the existence of different ecotypes of several commonly described hydrocarbon-degrading bacterial taxa which behaved differentially in coastal and offshore shelf waters despite being exposed to similar concentrations of oil, dispersants, and nutrients. This resulted in the differential expression of catabolic pathways for n -alkanes and polycyclic aromatic hydrocarbons (PAHs)-the two major categories of compounds found in crude oil-with preferential expression of n -alkane degradation genes in coastal waters while offshore microbial communities trended more toward the expression of PAH degradation genes. This was unexpected as it contrasts with the generally held view that n -alkanes, being more labile, are attacked before the more refractory PAHs. Collectively, our results provide new insights into the existence and potential consequences of niche partitioning of hydrocarbon-degrading taxa between neighboring marine environments. IMPORTANCE In the wake of the Deepwater Horizon oil spill, the taxonomic response of marine microbial communities to oil and dispersants has been extensively studied. However, relatively few studies on the functional response of these microbial communities have been reported, especially in a longitudinal fashion. Moreover, despite the fact that marine oil spills typically impact thousands of square kilometers of both coastal and offshore marine environments, little information is available on how the microbial response to oil and dispersants might differ between these biomes. The results of this study help fill this critical knowledge gap and provide valuable insight into how oil spill response efforts, such as chemically dispersing oil, may have differing effects in neighboring coastal and offshore marine environments., (Copyright © 2020 Doyle et al.)

Study Design: Cross-sectional survey., Objective: To determine the prevalence of back pain in American children and adolescents, with a focus on anatomic region, duration, severity, and treatment patterns, and to investigate for any predictive variables., Summary of Background Data: No study has examined the prevalence of back pain in American children and adolescents in the last 15 years. Because the prevalence of back pain varies greatly by country and year of investigation, previous studies are not generalizable., Methods: A United States epidemiologic cross-sectional survey-based investigation was performed in children and adolescents ages 10 and 18 years old, equally split by age and sex, and representing census-weighted distributions of state of residence, race/ethnicity, and health insurance status. Prevalence of back pain was evaluated and described., Results: In total, 1236 (33.7%) participants reported experiencing back pain within the last year and 325 (8.9%) reported severe back pain within the last year. Prevalence of back pain increased with age and was significantly more common in females, P < 0.001 for both. Treatment for back pain was sought by 505 (40.9%) of the participants with pain, of which physical therapy was the most common. Invasive procedural treatment (e.g., injections, surgery) were rare and comprised only 61 (1.6%) of study participants. In addition, government insurance and lack of insurance coverage was associated with low treatment seeking behavior compared to private insurance users (P = 0.010 and P = 0.006, respectively)., Conclusion: Despite how commonly it presents, the majority of young patients with back pain do not report procedural treatment such as injections or surgery. However, because many American children and adolescents seek treatment, future research on the etiology, treatment, and prevention of back pain in children and adolescents is essential to reducing a common and financially demanding problem., Level of Evidence: 4.

Puzzle-shaped pavement cells provide a powerful model system to investigate the cellular and subcellular processes underlying complex cell-shape determination in plants. To better understand pavement cell-shape acquisition and the role of auxin in this process, we focused on the spirals of young stomatal lineage ground cells of Arabidopsis leaf epidermis. The predictability of lobe formation in these cells allowed us to demonstrate that the auxin response gradient forms within the cells of the spiral and fluctuates based on the particular stage of lobe development. We revealed that specific localization of auxin transporters at the different membranes of these young cells changes during the course of lobe formation, suggesting that these fluctuating auxin response gradients are orchestrated via auxin transport to control lobe formation and determine pavement cell shape., Competing Interests: The authors declare no competing interest., (Copyright © 2020 the Author(s). Published by PNAS.)

Microbial heterotopic metabolism in the ocean is fueled by a supply of essential nutrients acquired via exoenzymes catalyzing depolymerization of high-molecular-weight compounds. Although the rates of activity for a variety of exoenzymes across various marine environments are well established, the factors regulating the production of these exoenzymes, and to some extent their correlation with microbial community composition, are less known. This study focuses on addressing these challenges using a mesocosm experiment that compared a natural seawater microbial community (control) and exposed (to oil) treatment. Exoenzyme activities for β-glucosidase, leucine aminopeptidase (LAP), and lipase were significantly correlated with dissolved nutrient concentrations. We measured correlations between carbon- and nitrogen-acquiring enzymes ( β -glucosidase/lipase versus LAP) and found that the correlation of carbon-acquiring enzymes varies with the chemical nature of the available primary carbon source. Notably, a strong correlation between particulate organic carbon and β -glucosidase activity demonstrates their polysaccharide depolymerization in providing the carbon for microbial growth. Last, we show that exoenzyme activity patterns are not necessarily correlated with prokaryotic community composition, suggesting a redundancy of exoenzyme functions among the marine microbial community and substrate availability. This study provides foundational work for linking exoenzyme function with dissolved organic substrate and downstream processes in marine systems. IMPORTANCE Microbes release exoenzymes into the environment to break down complex organic matter and nutrients into simpler forms that can be assimilated and utilized, thereby addressing their cellular carbon, nitrogen, and phosphorus requirements. Despite its importance, the factors associated with the synthesis of exoenzymes are not clearly defined, especially for the marine environment. Here, we found that exoenzymes associated with nitrogen and phosphorus acquisition were strongly correlated with inorganic nutrient levels, while those associated with carbon acquisition depended on the type of organic carbon available. We also show a linear relationship between carbon- and nitrogen-acquiring exoenzymes and a strong correlation between microbial biomass and exoenzymes, highlighting their significance to microbial productivity. Last, we show that changes in microbial community composition are not strongly associated with changes in exoenzyme activity profiles, a finding which reveals a redundancy of exoenzyme activity functions among microbial community. These findings advance our understanding of previously unknown factors associated with exoenzyme production in the marine environment., (Copyright © 2020 Kamalanathan et al.)

Purpose of Review: This review aims to provide primary care physicians with updates on recent literature regarding clubfoot and answer questions asked by parents and caregivers of children with clubfoot. The topics discussed include prenatal counseling, relapse after Ponseti treatment, long-term outcomes following successful treatment of clubfoot, and the effect of diagnosis and treatment on the parent or caregiver., Recent Findings: Clubfoot is one of the most commonly searched orthopaedic conditions on the internet by parents. There is a lack of evidence-based guidelines on clubfoot worldwide. Recent systematic reviews have identified emerging evidence of genetic and modifiable risk factors that lead to clubfoot. Patients treated by the Ponseti method show better ankle power and strength compared with those treated with surgery for residual deformity or recurrence., Summary: The treatment of clubfoot is a long and involved process. Exposure to and familiarity with the Ponseti method will aid primary care physicians and parents in the optimization of children's clubfoot deformity correction using largely nonoperative management.

distribution of auxin within plant tissues is of great importance for developmental plasticity, including root gravitropic growth. Auxin flow is directed by the subcellular polar distribution and dynamic relocalisation of auxin transporters such as the PIN-FORMED (PIN) efflux carriers, which can be influenced by the main natural plant auxin indole-3-acetic acid (IAA). Anthranilic acid (AA) is an important early precursor of IAA and previously published studies with AA analogues have suggested that AA may also regulate PIN localisation. Using Arabidopsis thaliana as a model species, we studied an AA-deficient mutant displaying agravitropic root growth, treated seedlings with AA and AA analogues and transformed lines to over-produce AA while inhibiting its conversion to downstream IAA precursors. We showed that AA rescues root gravitropic growth in the AA-deficient mutant at concentrations that do not rescue IAA levels. Overproduction of AA affects root gravitropism without affecting IAA levels. Treatments with, or deficiency in, AA result in defects in PIN polarity and gravistimulus-induced PIN relocalisation in root cells. Our results revealed a previously unknown role for AA in the regulation of PIN subcellular localisation and dynamics involved in root gravitropism, which is independent of its better known role in IAA biosynthesis., (© 2019 The Authors. New Phytologist © 2019 New Phytologist Trust.)

Members of the Hsp90 and Hsp70 families of molecular chaperones are imp\ortant for the maintenance of protein homeostasis and cellular recovery following environmental stresses, such as heat and oxidative stress. Moreover, the two chaperones can collaborate in protein remodeling and activation. In higher eukaryotes, Hsp90 and Hsp70 form a functionally active complex with Hop (Hsp90-Hsp70 organizing protein) acting as a bridge between the two chaperones. In bacteria, which do not contain a Hop homolog, Hsp90 and Hsp70, DnaK, directly interact during protein remodeling. Although yeast possesses a Hop-like protein, Sti1, Hsp90, and Hsp70 can directly interact in yeast in the absence of Sti1. Previous studies showed that residues in the middle domain of Escherichia coli Hsp90 are important for interaction with the J-protein binding region of DnaK. The results did not distinguish between the possibility that (i) these sites were involved in direct interaction and (ii) the residues in these sites participate in conformational changes which are transduced to other sites on Hsp90 and DnaK that are involved in the direct interaction. Here we show by crosslinking experiments that the direct interaction is between a site in the middle domain of Hsp90 and the J-protein binding site of Hsp70 in both E. coli and yeast. Moreover, J-protein promotes the Hsp70-Hsp90 interaction in the presence of ATP, likely by converting Hsp70 into the ADP-bound conformation. The identification of the protein-protein interaction site is anticipated to lead to a better understanding of the collaboration between the two chaperones in protein remodeling., (Published by Elsevier Ltd.)

Background: Prior reports suggest that osteoarticular infections may be increasing over time., Questions/purposes: We sought to determine if incidence rates, median in-hospital costs, and length of stay (LOS) of osteomyelitis, septic arthritis (SA), and combined infections have changed over time for pediatric patients, and how they compare to previously reported rates., Methods: The Kids' Inpatient Database (KID), a US national sample of pediatric hospital discharge records from 1997, 2000, 2003, 2006, 2009, and 2012, was used to determine yearly estimated counts of infections in children 20 years of age or younger. US census data was used to calculate yearly incidence rates. Trend tests using linear contrast analysis were used to compare estimated median LOS and inflation-adjusted median costs over time for each type of infection., Results: From 1997 through 2012, the incidence rate of osteomyelitis increased from 7.9 to 10.5 per 100,000, SA was unchanged from 5.3 to 5.2 per 100, and combined infections increased from 0.8 to 1.3 per 100,000. Median LOS from 1997 to 2012 showed no significant change for osteomyelitis (5.0 to 4.9 days), SA (4.4 to 4.1 days), or combined infections (6.5 to 6.8 days). Median in-hospital costs from 1997 to 2012 increased for osteomyelitis ($7735 to $11,823), SA ($5041 to $10,574), and combined infections ($12,691 to $16,260)., Conclusion: In pediatric patients, the estimated incidence rate of SA appeared stable, while rates of osteomyelitis and combined infections increased. These estimated rates fall within previously reported ranges. Despite stable LOS, costs have increased over time., Competing Interests: Conflict of InterestGabriella Safdieh, MD, Jason Silberman, BA, Joseph Nguyen, MPH, Shevaun Doyle, MD, John Blanco, MD, David Scher, MD, Daniel Green, MD, MS, Roger Widmann, MD, and Emily Dodwell, MD, MPH, FRCSC, declare that they have no conflict of interest. Joseph Nguyen, MPH, reports grants from Clinical Translational Science Center (CTSC), National Center for Advancing Translational Sciences (NCATS), outside the submitted work.

Background: Infants previously treated for developmental dysplasia of the hips (DDH) are routinely imaged with ultrasound initially and reimaged with an anteroposterior (AP) pelvis X-ray at 6 months of age to assess for dysplasia. It has become convention to transition from ultrasound to AP X-ray at 6 months of age, but no study has demonstrated that ultrasound is inadequate at this age., Question/purpose: The purpose of this study was to confirm that ultrasound for the 6-month DDH evaluation is a feasible alternative to the standard X-ray., Patients and Methods: Thirty-one 5- to 7-month-old infants undergoing AP pelvis X-ray related to previous Pavlik harness treatment for DDH or to a history of breech presentation were prospectively enrolled. All patients were imaged with an AP pelvis X-ray and bilateral hip ultrasounds. Three senior orthopedic surgeons unfamiliar with the patient histories evaluated both types of imaging for standard measures of hip dysplasia, including acetabular index (AI), alpha angle, and bony rim percent coverage of the femoral head. Pearson correlation coefficients were calculated for the X-ray and ultrasound measures., Results: Good quality ultrasound images were obtained in all patients, despite the presence of the ossific nucleus in 66% of the hips. All three reviewers correctly diagnosed the one dislocated hip via both X-ray and ultrasound. There were no false negatives on ultrasound, and none of the patients with negative ultrasounds required treatment during the mean 26 months of follow up. An increased AI on X-ray was correlated with lower percent coverage of the femoral head on ultrasound., Conclusions: Ultrasound is a technically feasible DDH imaging modality that can be used as an alternative to X-ray for 6-month-olds., Competing Interests: Conflict of InterestAlison Kitay, MD, Roger F. Widmann, MD, Shevaun M. Doyle, MD, Huong T. Do, MA, and Daniel W. Green, MD, declare that they have no conflicts of interest.

Heat shock protein 90 (Hsp90) is a highly conserved molecular chaperone involved in ATP-dependent client protein remodeling and activation. It also functions as a protein holdase, binding and stabilizing clients in an ATP-independent process. Hsp90 remodels over 300 client proteins and is essential for cell survival in eukaryotes. In bacteria, Hsp90 is a highly abundant protein, although very few clients have been identified and it is not essential for growth in many bacterial species. We previously demonstrated that in Escherichia coli , Hsp90 causes cell filamentation when expressed at high levels. Here, we have explored the cause of filamentation and identified a potentially important client of E. coli Hsp90 (Hsp90 Ec ), FtsZ. We observed that FtsZ, a bacterial tubulin homolog essential for cell division, fails to assemble into FtsZ rings (divisomes) in cells overexpressing Hsp90 Ec Additionally, Hsp90 Ec interacts with FtsZ and inhibits polymerization of FtsZ in vitro, in an ATP-independent holding reaction. The FtsZ-Hsp90 Ec interaction involves residues in the client-binding region of Hsp90 Ec and in the C-terminal tail of FtsZ, where many cell-division proteins and regulators interact. We observed that E. coli deleted for the Hsp90 Ec gene htpG turn over FtsZ more rapidly than wild-type cells. Additionally, the length of Δ htpG cells is reduced compared to wild-type cells. Altogether, these results suggest that Hsp90 Ec is a modulator of cell division, and imply that the polypeptide-holding function of Hsp90 may be a biologically important chaperone activity., Competing Interests: The authors declare no conflict of interest.

Auxin phytohormones control most aspects of plant development through a complex and interconnected signaling network. In the presence of auxin, AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) transcriptional repressors are targeted for degradation by the SKP1-CULLIN1-F-BOX (SCF) ubiquitin-protein ligases containing TRANSPORT INHIBITOR RESISTANT 1/AUXIN SIGNALING F-BOX (TIR1/AFB). CULLIN1-neddylation is required for SCF TIR1/AFB functionality, as exemplified by mutants deficient in the NEDD8-activating enzyme subunit AUXIN-RESISTANT 1 (AXR1). Here, we report a chemical biology screen that identifies small molecules requiring AXR1 to modulate plant development. We selected four molecules of interest, RubNeddin 1 to 4 (RN1 to -4), among which RN3 and RN4 trigger selective auxin responses at transcriptional, biochemical, and morphological levels. This selective activity is explained by their ability to consistently promote the interaction between TIR1 and a specific subset of AUX/IAA proteins, stimulating the degradation of particular AUX/IAA combinations. Finally, we performed a genetic screen using RN4, the RN with the greatest potential for dissecting auxin perception, which revealed that the chromatin remodeling ATPase BRAHMA is implicated in auxin-mediated apical hook development. These results demonstrate the power of selective auxin agonists to dissect auxin perception for plant developmental functions, as well as offering opportunities to discover new molecular players involved in auxin responses., Competing Interests: The authors declare no conflict of interest., (Copyright © 2019 the Author(s). Published by PNAS.)

Heat shock proteins 90 (Hsp90) and 70 (Hsp70) are two families of highly conserved ATP-dependent molecular chaperones that fold and remodel proteins. Both are important components of the cellular machinery involved in protein homeostasis and participate in nearly every cellular process. Although Hsp90 and Hsp70 each carry out some chaperone activities independently, they collaborate in other cellular remodeling reactions. In eukaryotes, both Hsp90 and Hsp70 function with numerous Hsp90 and Hsp70 co-chaperones. In contrast, bacterial Hsp90 and Hsp70 are less complex; Hsp90 acts independently of co-chaperones, and Hsp70 uses two co-chaperones. In this review, we focus on recent progress toward understanding the basic mechanisms of Hsp90-mediated protein remodeling and the collaboration between Hsp90 and Hsp70, with an emphasis on bacterial chaperones. We describe the structure and conformational dynamics of these chaperones and their interactions with each other and with client proteins. The physiological roles of Hsp90 in Escherichia coli and other bacteria are also discussed. We anticipate that the information gained from exploring the mechanism of the bacterial chaperone system will provide the groundwork for understanding the more complex eukaryotic Hsp90 system and its modulation by Hsp90 co-chaperones.

Purpose of Review: Provide a comprehensive overview of lumbar spondylolysis, a frequent cause of lower back pain in children and adolescents, from evaluation to management., Recent Findings: With the surge of structured sports participation in the pediatric population, spondylolysis is a common ailment that afflicts many young athletes due to rigorous competition that taxes the growing spine with repetitive extension and rotation., Summary: Spondylolysis is a fracture through the pars interarticularis. When a child presents with lower back pain, spondylolysis should be at the top of the differential. A thorough history and physical examination are essential. In addition, radiographs of the lumbar spine, anterior posterior and lateral views, MRI and, selectively, computed tomography are useful adjuncts to uncover a pars injury. Timely diagnosis facilitates early treatment which includes rest, optimizing bone health, brace treatment, and physical therapy. If delayed or untreated, spondylolysis may result in nonunion or pars defect. If symptomatic, patients may need surgery to fuse the lumbar facet joints or repair the par interarticularis.

Background: There is no standardized complication classification system that has been evaluated for use in pediatric or general orthopaedic surgery. Instead, subjective terms such as major and minor are commonly used. The Clavien-Dindo-Sink complication classification system has demonstrated high interrater and intrarater reliability for hip-preservation surgery and has increasingly been used within other orthopaedic subspecialties. This classification system is based on the magnitude of treatment required and the potential for each complication to result in long-term morbidity. The purpose of the current study was to modify the Clavien-Dindo-Sink system for application to all orthopaedic procedures (including those involving the spine and the upper and lower extremity) and to determine interrater and intrarater reliability of this modified system in pediatric orthopaedic surgery cases., Methods: The Clavien-Dindo-Sink complication classification system was modified for use with general orthopaedic procedures. Forty-five pediatric orthopaedic surgical scenarios were presented to 7 local fellowship-trained pediatric orthopaedic surgeons at 1 center to test internal reliability, and 48 scenarios were then presented to 15 pediatric orthopaedic surgeons across the United States and Canada to test external reliability. Surgeons were trained to use the system and graded the scenarios in a random order on 2 occasions. Fleiss and Cohen kappa (κ) statistics were used to determine interrater and intrarater reliabilities, respectively., Results: The Fleiss κ value for interrater reliability (and standard error) was 0.76 ± 0.01 (p < 0.0001) and 0.74 ± 0.01 (p < 0.0001) for the internal and external groups, respectively. For each grade, interrater reliability was good to excellent for both groups, with an overall range of 0.53 for Grade I to 1 for Grade V. The Cohen κ value for intrarater reliability was excellent for both groups, ranging from 0.83 (95% confidence interval [CI], 0.71 to 0.95) to 0.98 (95% CI, 0.94 to 1.00) for the internal test group and from 0.83 (95% CI, 0.73 to 0.93) to 0.99 (95% CI, 0.97 to 1.00) for the external test group., Conclusions: The modified Clavien-Dindo-Sink classification system has good interrater and excellent intrarater reliability for the evaluation of complications following pediatric orthopaedic upper extremity, lower extremity, and spine surgery. Adoption of this reproducible, reliable system as a standard of reporting complications in pediatric orthopaedic surgery, and other orthopaedic subspecialties, could be a valuable tool for improving surgical practices and patient outcomes.

Background: The randomized controlled trial (RCT) is the gold standard study design allowing critical comparison of clinical outcomes while minimizing bias. Traditionally clinical trials are evaluated through statistical significance, expressed by P-values and confidence intervals. However, until recently, the robustness of a study's conclusions has been given little attention. A new metric, the fragility index, quantifies the number of patients theoretically required to switch outcomes in order to reverse the study conclusions. The primary aim of our work was to determine the fragility index of RCTs in the pediatric orthopaedic literature. The secondary aim was to determine study factors associated with lower fragility index., Methods: Pubmed and Embase were systematically searched for pediatric orthopaedic RCTs published September 1, 2006 to September 1, 2016. Two independent reviewers screened titles, abstracts, and manuscripts to identify studies published in English involving 2 treatment arms. Trials without dichotomous primary or secondary outcomes or with patients >18 years were excluded. Data were extracted from each eligible article in duplicate and the fragility index was determined using Fisher exact test, with previously published methods. Univariate analysis was used to determine factors associated with lower fragility index., Results: Seventeen trials were eligible for inclusion. The median treatment arm size was 58 and overall sample size was 116 patients. The median fragility index was 3 (range, 0 to 18). A fragility index of 3 means that just 3 patients would need to switch treatment outcomes in order for the trial results to become statistically nonsignificant. In 1 study, the number of patients lost to follow-up exceeded the fragility index, such that the study conclusions could be completely reversed purely depending on the outcomes of the patients lost to follow-up. Lower fragility index was associated with smaller patient sample sizes and greater P-values., Conclusions: The fragility index is a useful adjunct metric to the P-value and confidence intervals, allowing analysis of the robustness of study conclusions. RCTs in pediatric orthopaedics often have small sample sizes, many with low fragility indices. Future efforts could focus on encouraging institutional collaboration and patient recruitment with the ultimate goal of improving RCT sample sizes, and potentially improving the robustness of RCT results., Level of Evidence: Level I.

Background: Clubfoot is a common congenital anomaly with multiple potential risk factors. Identification of modifiable risk factors may minimize future incidence of clubfoot. The aim of this meta-analysis was to systematically review and analyze the best clinical evidence regarding risk factors associated with clubfoot., Methods: Medline, Embase, and Cochrane databases were systematically searched from 1967 to May 11, 2016 for studies reporting risk factors for clubfoot. Randomized trials and observational studies were eligible for inclusion, and assessed in duplicate. Study quality was assessed with the Newcastle-Ottawa Scale or Cochrane risk of bias tool; low quality studies were excluded, all randomized trials were included. Two reviewers extracted data independently. This meta-analysis was conducted in accordance with PRISMA guidelines. Pooled effect estimates for the odds of clubfoot were calculated using random or fixed-effects models based on heterogeneity., Results: Forty-two studies (28 case-control, 10 cohort, 4 randomized trials) comprising 31,844 clubfoot cases and 6,604,013 controls were included. Risk factors associated with increased odds of clubfoot included maternal smoking [odds ratio (OR)=1.65; 95% confidence interval (CI), 1.54-1.78], paternal smoking (OR=1.72; 95% CI, 1.05-2.84), maternal body mass index >30 (OR=1.46; 95% CI, 1.29-1.65), family history (OR=7.80; 95% CI, 4.04-15.04), amniocentesis (OR=2.08; 95% CI, 1.34-3.21), selective serotonin reuptake inhibitor exposure (OR=1.78; 95% CI, 1.34-2.37) maternal single status (OR=1.17; 95% CI, 1.11-1.23), gestational diabetes (OR=1.40; 95% CI, 1.13-1.72), nulliparity (OR=1.32; 95% CI, 1.19-1.45), male sex (OR=1.68; 95% CI, 1.48-1.94), and aboriginal Australian race (OR=2.35; 95% CI, 1.63-3.38)., Conclusions: Smoking, maternal obesity, family history, amniocentesis, and some selective serotonin reuptake inhibitor exposures are the most clinically relevant exposures associated with increased odds of clubfoot, with family history representing the greatest risk. Recognition of modifiable risk factors may help in counseling patients, and minimizing clubfoot incidence., Level of Evidence: Level II.

Background: Glaciers cover ~ 10% of land but are among the least explored environments on Earth. The basal portion of glaciers often harbors unique aquatic microbial ecosystems in the absence of sunlight, and knowledge on the microbial community structures and their metabolic potential is very limited. Here, we provide insights into the microbial lifestyle present at the base of the Matanuska Glacier, Alaska., Results: DNA and RNA were extracted from samples of the Matanuska Glacier basal ice. Using Illumina MiSeq and HiSeq sequencing, we investigated the microbial diversity with the metagenomic shotgun reads and 16S ribosomal RNA data. We further assembled 9 partial and draft bacterial genomes from the metagenomic assembly, and identified key metabolic pathways such as sulfur oxidation and nitrification. Collectively, our analyses suggest a prevalence of lithotrophic and heterotrophic metabolisms in the subglacial microbiome., Conclusion: Our results present the first metagenomic assembly and bacterial draft genomes for a subglacial environment. These results extend our understanding of the chemical and biological processes in subglacial environments critically influenced by global climate change.

Extracellular enzymes and extracellular polymeric substances (EPS) play a key role in overall microbial activity, growth and survival in the ocean. EPS, being amphiphilic in nature, can act as biological surfactant in an oil spill situation. Extracellular enzymes help microbes to digest and utilize fractions of organic matter, including EPS, which can stimulate growth and enhance microbial activity. These natural processes might have been altered during the 2010 Deepwater Horizon oil spill due to the presence of hydrocarbon and dispersant. This study aims to investigate the role of bacterial extracellular enzymes during exposure to hydrocarbons and dispersant. Mesocosm studies were conducted using a water accommodated fraction of oil mixed with the chemical dispersant, Corexit (CEWAF) in seawater collected from two different locations in the Gulf of Mexico and corresponding controls (no additions). Activities of five extracellular enzymes typically found in the EPS secreted by the microbial community - α- and β-glucosidase, lipase, alkaline phosphatase, leucine amino-peptidase - were measured using fluorogenic substrates in three different layers of the mesocosm tanks (surface, water column and bottom). Enhanced EPS production and extracellular enzyme activities were observed in the CEWAF treatment compared to the Control. Higher bacterial and micro-aggregate counts were also observed in the CEWAF treatment compared to Controls. Bacterial genera in the order Alteromonadaceae were the most abundant bacterial 16S rRNA amplicons recovered. Genomes of Alteromonadaceae commonly have alkaline phosphatase and leucine aminopeptidase, therefore they may contribute significantly to the measured enzyme activities. Only Alteromonadaceae and Pseudomonadaceae among bacteria detected here have higher percentage of genes for lipase. Piscirickettsiaceae was abundant; genomes from this order commonly have genes for leucine aminopeptidase. Overall, this study provides insights into the alteration to the microbial processes such as EPS and extracellular enzyme production, and to the microbial community, when exposed to the mixture of oil and dispersant.