Functional layer-by-layer design of xerogel-based first-generation amperometric glucose biosensors.

Xerogel-based first-generation amperometric glucose biosensors, constructed through specific layer-by-layer assembly of films featuring glucose oxidase doped xerogel, a diffusion-limiting xerogel layer, and capped with both electropolymerized polyphenol and blended polyurethane semipermeable membranes, are presented. The specific combination of xerogels formed from specific silane precursors, including propyl-trimethoxysilane, isobutyl-trimethoxysilane, octyl-trimethoxysilane, and hydroxymethyl-triethoxysilane, exhibit impressive dynamic and linear ranges of detection (e.g., ≥24-28 mM glucose) and low response times, as well as significant discrimination against common interferent species such as acetaminophen, ascorbic acid, sodium nitrite, oxalic acid, and uric acid as determined by selectivity coefficients. Additionally, systematic electrochemical and contact angle studies of different xerogel silane precursors, varying in structure, chain length, and/or functional group, reveal that sensor performance is more dependent on the tunable porosity/permeability of the layered interfaces rather than the hydrophobic character or functional groups within the films. While the sensing performance largely exceeds that of existing electrochemical glucose sensing schemes in the literature, the presented layered approach establishes the specific functionality of each layer working in concert with each other and suggests that the strategy may be readily adaptable to other clinically relevant targets and is amenable to miniaturization for eventual in situ or in vivo sensing.

Potential use of pinenes to improve localized insecticide injections targeting the western drywood termite (Blattodea: Kalotermitidae).

The western drywood termite, Incisitermes minor (Hagen), causes significant economic damage to wood structures in the United States of America, especially California. When infestation is not widespread, localized insecticide injections may be useful for remedial control. However, the extensive gallery structure of drywood termites and their tendency to aggregate at specific parts of the galleries can impact the efficacy of localized insecticide injection. Chemicals that attract termites from a distance may improve the localized insecticide injection by increasing the number of termites contacting the insecticide residues. Two volatile terpenes, α-pinene and ß-pinene, commonly found in many coniferous timber trees, were applied to artificial termite galleries to determine if termites were attracted from their original aggregation site. Furthermore, we examined if adding these pinenes would improve the overall efficacy of some insecticide products for drywood termite control. Behavioral assay results showed that the treatment with pinenes increased the likelihood that drywood termites would leave their original aggregation site and contact the treated part of the gallery. When tested with the pesticide products applied in a small area away from the termite aggregation, ß-pinene significantly accelerated the time course of mortality for the aqueous fipronil. The efficacy of disodium octaborate tetrahydrate dust was not influenced by the addition of pinenes. Implications for drywood termite management and future research directions are discussed.

Can We Just Play? Internal Validity of Assessing Physiological State With a Semistandardized Kicking Drill in Professional Australian Football.

PURPOSE: To examine associations between exercise heart rate (HRex) during a continuous-fixed submaximal fitness test (CF-SMFT) and an intermittent-variable protocol (semistandardized kicking drill [SSD]) in Australian Football athletes, controlling for external intensities, within-session scheduling, and environmental conditions. METHODS: Forty-four professional male Australian Football athletes (22.8 [8.0] y) were monitored over 10 sessions involving a 3-minute CF-SMFT (12 km·h-1) as the first activity and a SSD administered 35.7 (8.0) minutes after the CF-SMFT. Initial heart rate and HRex were collected, with external intensities measured as average velocity (in meters per minute) and average acceleration-deceleration (in meters per second squared). Environmental conditions were sampled. A penalized hierarchical linear mixed model was tuned for a Bayesian information criterion minima using a 10-fold cross-validation, with out-of-sample prediction accuracy assessed via root-mean-squared error. RESULTS: SSD average acceleration-deceleration, initial heart rate, temperature, and ground hardness were significant moderators in the tuned model. When model covariates were held constant, a 1%-point change in SSD HRex associated with a 0.4%-point change in CF-SMFT HRex (95% CI, 0.3-0.5). The tuned model predicted CF-SMFT HRex with an average root-mean-squared error of 2.64 (0.57) over the 10-fold cross-validation, with 74% and 86% of out-of-sample predictions falling within 2.7%-points and 3.7%-points, respectively, from observed values, representing the lower and upper limits for detecting meaningful changes in HRex according to the documented typical error. CONCLUSIONS: Our findings support the use of an SSD to monitor physiological state in Australian Football athletes, despite varied scheduling within session. Model predictions of CF-SMFT HRex from SSD HRex closely aligned with observed values, considering measurement imprecision.

Delayed Presentation of Displaced Salter-Harris III Distal Tibia Fracture: Does Transfracture Reduction Yield Satisfactory Outcomes?

LEVELS OF EVIDENCE: Level V.

Surgical Management and Return to Activity of an Athlete with Traumatic Posterior Tibial Tendon Rupture and Associated Injuries: A Case Report.

CASE: A 22-year-old athlete sustained a traumatic posterior tibial tendon (PTT) rupture with medial malleolus fracture and anterior tibial plafond chondral lesion during practice. He underwent PTT repair, ankle arthroscopy with microfracture, and medial malleolus open reduction and internal fixation with deltoid ligament repair. At 1 year postoperatively, the patient returned to activity excluding high-level competition. CONCLUSION: Anterior tibial chondral impaction injury with an avulsion fracture of the medial malleolus and PTT tear is effectively treated with a combined arthroscopic and open approach.

The International Classification of Disease Critical Care Severity Score demonstrates that pediatric burden of injury is similar to that of adults: Validation using the National Trauma Databank☆.

BACKGROUND/PURPOSE: Resource-based severity of injury (SOI) measures, such as the International Classification of Disease (ICD) Critical Care Severity Score (ICASS), may characterize traumatic burden better than standard mortality-based measures. The purpose of this study was to validate the ICASS in a representative national-level trauma cohort and compare SOI measures between children and adults. METHODS: The National Trauma Databank was used to derive (2008-12) and validate (2013-15) ICASS and ICD Injury Severity Scores (ICISS, standard mortality-based SOI measure). SOI metrics and outcomes were compared between pediatric, adult, and elderly age groups. Logistic regression modeling evaluated predictors of critical care resource utilization. RESULTS: Derivation and validation cohorts consisted of 3.90 and 1.97 million patients, respectively. ICASS strongly predicted actual critical care utilization (OR 1.04, 95% CI 1.04-1.04, p<0.0001). Mean ICASS was 24.4 for children and 33.0 for adults (ratio 0.74), indicating predicted critical care utilization in children was three-quarters that of adults. In contrast, predicted pediatric mortality was less than half that of adults. CONCLUSIONS: Mortality-based SOI measures underestimate pediatric burden of injury. This study validates ICASS and demonstrates that pediatric resource-based SOI is more similar to that of adults. ICASS is easily calculated without a trauma registry and complements mortality-based measures. Level of evidence III, retrospective comparative study.

Olecranon Fracture in an Older Adult Treated With Locking Plate Osteosynthesis.

Although olecranon fractures are not uncommon in the geriatric population, there has been a considerable difference of opinion between surgical and nonsurgical treatments. Surgical treatment is usually deferred in the elderly, even for displaced olecranon fractures, because of inherent risks associated with poor bone quality and soft tissues, which often necessitate further surgeries. However, nonoperative treatment frequently results in an inability to regain full extension strength of the elbow, which can be disabling in select older adults with higher functional demands. We present an active older adult with a displaced olecranon fracture, who achieved a satisfactory result after open reduction and internal fixation (ORIF) using a low-profile locking plate.

Determinants of the variability of heart rate measures during a competitive period in young soccer players.

Measurements of exercise heart rate (HR(ex)), HR recovery (HRR) and HR variability (HRV) are used as indices of training status. However, the day-to-day variability of these indices throughout a competitive soccer period is unknown. On 14 occasions during a 3-week competition camp, 18 under 15 (U15) and 15 under 17 (U17) years soccer players performed a 5-min submaximal run, followed by a seated 5-min recovery period. HR(ex) was determined during the last 30 s of exercise, while HRR and HRV were measured during the first and last 3 min of the post-exercise recovery period, respectively. U15 players displayed greater HR(ex) (P = 0.02) and HRR (P = 0.004) compared with the U17 players, but there was no difference in HRV (P = 0.74). The mean coefficient of variation (CV) for HR(ex) was lower than that for HRV [3.4 (90% CL, 3.1, 3.7) vs. 10.7 (9.6, 11.9)%, P < 0.001]; both were lower than that for HRR [13.3 (12.2, 14.3)%, P < 0.01]. In contrast to HR(ex) and HRR, the CV for HRV was correlated to maximal aerobic speed (r = -0.52, P = 0.002). There was no correlation between total activity time (training sessions + matches) and CV of any of the quantified variables. The variability of each of these measures and player fitness levels should be considered when interpreting changes in training status.

Two novel resource-based metrics to quantify pediatric trauma severity based on probability of requiring critical care and anesthesia services.

BACKGROUND: Mortality-based metrics like the International Classification of Diseases (ICD) Injury Severity Score (ICISS) may underestimate burden of pediatric traumatic disease due to lower mortality rates in children. The purpose of this study was to develop and validate two resource-based severity of injury (SOI) measures, then compare these measures and the ICISS across a broad age spectrum of injured patients. METHODS: The ICISS and two novel SOI measures, termed ICD Critical Care Severity Score (ICASS) and ICD General Anesthesia Severity Score (IGASS), were derived from Florida state administrative 2012 to 2016 data and validated with 2017 data. The ICASS and IGASS predicted the need for critical care services and anesthesia services, respectively. Logistic regression was used to validate each SOI measure. Distributions of ICISS, ICASS, and IGASS were compared across pediatric (0-15 years), adult (16-64 years), and elderly (65-84 years) age groups. RESULTS: The derivation and validation cohorts consisted of 668,346 and 24,070 emergency admissions, respectively. On logistic regression, ICISS, ICASS, and IGASS were strongly predictive of observed mortality, critical care utilization, and anesthesia utilization, respectively (p < 0.001). The mean ICISS was 10.6 for pediatric and 19.0 for adult patients (ratio, 0.56), indicating that the predicted mortality risk in pediatric patients was slightly over half that of adults. In contrast, the mean ICASS for pediatric and adult patients was 50.2 and 53.2, respectively (ratio, 0.94); indicating predicted critical care utilization in pediatric patients was nearly the same as that of adults. The IGASS comparisons followed comparable patterns. CONCLUSION: When a mortality-based SOI measure is used, the severity of pediatric injury appears much lower than that of adults, but when resource-based measures are used, pediatric and adult burden of injury appear very similar. The ICASS and IGASS are novel and valid resource-based SOI measures that are easily calculated with administrative data. They may complement mortality-based measures in pediatric trauma. LEVEL OF EVIDENCE: Level III, prognostic and epidemiological study.

Field Triage of Motor Vehicle Crashes: Which Factors Predict High Injury Severity?

Patient physiology and crash characteristics are essential components of field triage for motor vehicle crashes. We aimed to identify prehospital information that predicted high injury severity or critical patient condition on hospital arrival. The association of demographics, shock index (SI), Glasgow Coma Scale, and 10 crash characteristics of trauma activations for motor vehicle crashes with injury severity score (ISS) ≥ 16 and a composite of hypotension, need for blood transfusions, or immediate operation was determined using univariate and multivariate analyses. A total of 133 of 498 patients (27%) had ISS ≥ 16; SI ≥ 0.9, Glasgow Coma Scale ≤ 8, speed ≥ 55 mph, seatbelt use, airbag deployment, ambulatory patient, severe vehicle damage, ejection, and extrication were associated with ISS ≥ 16. Only abnormal SI and high speed remained independent predictors for ISS ≥ 16 with Odds Ratio (OR) = 10.76 (95% confidence interval (CI), 1.14-101, P = 0.04) and OR = 10.37 (95% CI, 1.48-72.93, P = 0.02), respectively. SI ≥ 0.9 predicted the composite outcome with OR = 5.92 (95% CI, 2.32-15.08, P < 0.01). Many commonly reported crash characteristics did not predict clinically important outcomes. Improvements in road and vehicle safety may be resulting in lower injury severity despite major crash mechanisms.

The Effect of Body Mass on Eccentric Knee-Flexor Strength Assessed With an Instrumented Nordic Hamstring Device (Nordbord) in Football Players.

PURPOSE: To examine the effect of body mass (BM) on eccentric knee-flexor strength using the Nordbord and offer simple guidelines to control for the effect of BM on knee-flexor strength. METHODS: Data from 81 soccer players (U17, U19, U21, senior 4th French division, and professionals) and 41 Australian Football League (AFL) players were used for analysis. They all performed 1 set of 3 maximal repetitions of the bilateral Nordic hamstring exercise, with the greatest strength measure used for analysis. The main regression equation obtained from the overall sample was used to predict eccentric knee-flexor strength from a given BM (moderate TEE, 22%). Individual deviations from the BM-predicted score were used as a BM-free index of eccentric knee- flexor strength. RESULTS: There was a large (r = .55, 90% confidence limits .42;.64) correlation between eccentric knee-flexor strength and BM. Heavier and older players (professionals, 4th French division, and AFL) outperformed their lighter and younger (U17-U21) counterparts, with the soccer professionals presenting the highest absolute strength. Professional soccer players were the only ones to show strength values likely slightly greater than those expected for their BM. CONCLUSIONS: Eccentric knee-flexor strength, as assessed with the Nordbord, is largely BM-dependent. To control for this effect, practitioners may compare actual test performances with the expected strength for a given BM, using the following predictive equation: Eccentric strength (N) = 4 × BM (kg) + 26.1. Professional soccer players with specific knee-flexor-training history and enhanced neuromuscular performance may show higher than expected values.

Structure-function relationships affecting the sensing mechanism of monolayer-protected cluster doped xerogel amperometric glucose biosensors.

A systematic study of the structure-function relationships critical to understanding the sensing mechanism of 1st generation amperometric glucose biosensors with an embedded nanoparticle (NP) network is presented. Xerogel-based films featuring embedded glucose oxidase enzyme and doped with alkanethiolate-protected gold NPs, known as monolayer protected clusters (MPCs), exhibit significantly enhanced performance compared to analogous systems without NPs including higher sensitivity, faster response time, and extended linear/dynamic ranges. The proposed mechanism involves diffusion of the glucose to glucose oxidase within the xerogel, enzymatic reaction production of H2O2 with subsequent diffusion to the embedded network of MPCs where it is oxidized, an event immediately reported via fast electron transfer (ET) through the MPC system to the working electrode. Various aspects of the film construct and strategy are systematically probed using amperometry, voltammetry, and solid-state electronic conductivity measurements, including the effects of MPC peripheral chain length, MPC functionalization via place-exchange reaction, MPC core size, and the MPC density or concentration within the xerogel composite films. The collective results of these experiments support the proposed mechanism and identify interparticle spacing and the electronic communication through the MPC network is the most significant factor in the sensing scheme with the diffusional aspects of the mechanism that may be affected by film/MPC hydrophobicity and functionality (i.e., glucose and H2O2 diffusion) shown to be less substantial contributors to the overall enhanced performance. Understanding the structure-function relationships of effective sensing schemes allows for the employment of the strategy for future biosensor design toward clinically relevant targets.

The use of veno-venous extracorporeal membrane oxygenation for perinatal support of an infant with d-transposition of the great arteries, intact atrial and ventricular septa, and flow-restricted ductus arteriosus.

Prenatal assessment of a fetus with D-transposition of the great arteries demonstrated an absence of mixing between systemic and pulmonary circulations, and predicted lethal postnatal hypoxemia. A multidisciplinary meeting evaluated therapeutic options. After cesarean delivery, veno-venous extracorporeal membrane oxygenation was instituted in preparation for open atrial septectomy. The infant subsequently underwent an arterial switch procedure. Prenatal delineation of pulmonary and systemic circulations in the fetus with D-transposition of the great arteries influences postnatal management. Multidisciplinary planning enhanced the perinatal outcome.

Evaluation of a novel calcium phosphate-coated titanium porous oxide implant surface: a study in rabbits.

PURPOSE: To evaluate osseointegration of a novel calcium phosphate (CaP)-coated titanium porous oxide implant surface. MATERIALS AND METHODS: Twenty adult male New Zealand White rabbits were used. Each animal received two titanium porous oxide-surfaced implants (benchmark control: TiUnite, Nobel Biocare) and two novel CaP-coated titanium porous oxide-surfaces implants; they were randomly allocated to contralateral tibia implant sites. The animals were sacrificed after 2 or 4 weeks, and tissues were evaluated histometrically. RESULTS: Healing was generally uneventful. A removal torque analysis showed significantly higher mean (± SE) peak values for the control implants than for the test implants at 2 weeks (31.4 ± 2.5 Ncm versus 20.4 ± 1.8 Ncm) and 4 weeks (48.4 ± 5.5 Ncm versus 30.3 ± 3.9 Ncm). Light microscopy showed no significant differences in local bone density around control and test implants at 2 and 4 weeks (range, 85% to 91% within the thread area and 91% to 95% immediately outside the threads). At 2 weeks, bone-implant contact for control and test implants averaged 81.8% ± 2.8% and 75.7% ± 4.6%, respectively, and at 4 weeks the bone-implant contact values were 79.4% ± 2.8% and 73.5% ± 4.2%, respectively; these differences were not significant. Backscatter scanning electron microscopy also showed no significant differences in local bone density at control and test implants at 2 and 4 weeks (range, 55% to 72% within the thread area and 75% to 81% immediately outside the threads). At 2 weeks, bone-implant contact for control and test implants averaged 66.4% ± 2.9% and 61.5% ± 5.1%, respectively, and at 4 weeks mean values were 60.1% ± 4.2% and 53.3% ± 4.6% (differences not significant). CONCLUSIONS: The results suggest that the novel CaP-coated surface effectively supports osseointegration.

Staged reconstruction of large congenital diaphragmatic defects with synthetic patch followed by reverse latissimus dorsi muscle.

BACKGROUND/PURPOSE: Synthetic repair of large congenital diaphragmatic defects (>90%) invariably will lead to recurrence, progressive chest wall deformity, and restrictive pulmonary disease. Staged reconstruction with living, growing tissue can help avoid these complications. METHODS: Between November 1995 and December 1999, 5 patients (median age, 25 months) with diaphragmatic agenesis underwent staged replacement with a reverse latissimus dorsi (RLD) flap. All required extracorporeal membrane oxygenation (ECMO) support at birth followed by synthetic patch (polytetrafluoroethylene or PTFE) diaphragm closure. Clinical evidence of patch disproportion, including recurrence (n = 3), chest wall deformity (n = 3), radiographic findings (n = 2), and restrictive respiratory patterns (n = 1), provided indication for replacement. The procedure involves removal of the original patch via thoracotomy followed by transposition of a RLD flap (based on the paraspinous and intercostal perforating vessels) into the defect through the bed of the 10th rib. Two patients underwent concomitant fundoplication. RESULTS: RLD flap was completed successfully in all 5 patients. Median length of stay after the procedure was 8 days. With a mean follow-up of 28 months (15 to 64 months), there have been no recurrences and no complications related to the procedure. Respiratory status and chest wall deformity have improved. There was neither evidence of paradoxical chest wall movement nor obvious limitation of the ipsilateral upper extremity on physical examination. The RLD flaps have grown proportionately to the children and remained at a stable level on chest x-ray. CONCLUSIONS: Staged reconstruction with patch closure followed by definitive reverse latissimus dorsi flap repair is a safe and highly effective treatment option in patients with diaphragmatic agenesis. A planned replacement should be considered in all patients with severe diaphragmatic hernias and patch closure before the development of thoracic complications.

Duplication of the cervical esophagus: a case report and review of the literature.

This report describes a newborn with a cervical esophageal duplication cyst, a rare developmental anomaly of the neck. Only a few cases of this cystic entity have been described in the literature to date. This case is unique in that the patient had an air-fluid level within the lesion as a result of communication of the duplication cyst with the native esophagus.