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Background: The orthopaedic literature contains relatively little quantitative information regarding the anatomy of the posterior aspect of the knee. The purpose of the present study was to provide a detailed description of, and to propose a standard nomenclature for, the anatomy of the posterior aspect of the knee.Methods: Detailed dissection of twenty nonpaired, fresh-frozen knees was performed. Posterior knee structures were measured according to length, width, and/or distance to reproducible osseous landmarks.Results: The semimembranosus tendon had eight attachments distal to the main common tendon. The main components were a lateral expansion to the oblique popliteal ligament; a direct arm, which attached to the tibia; and an anterior arm. The oblique popliteal ligament, the largest posterior knee structure, formed a broad fascial sheath over the posterior aspect of the knee and measured 48.0 mm in length and 9.5 mm wide at its medial origin and 16.4 mm wide at its lateral attachment. It had two lateral attachments, one to the meniscofemoral portion of the posterolateral joint capsule and one to the tibia, along the lateral border of the posterior cruciate ligament facet. The semimembranosus also had a distal tibial expansion, which formed a posterior fascial layer over the popliteus muscle. A thickening of the posterior joint capsule, the proximal popliteus capsular expansion, which in this study averaged 40.5 mm in length, connected the posteromedial knee capsule at its attachment at the intercondylar notch to the medial border of the popliteus musculotendinous junction. The plantaris muscle, popliteofibular ligament, fabellofibular ligament, and semimembranosus bursa were present in all specimens.Conclusions: The anatomy of the posterior aspect of the knee is quite complex. This study provides information that can lead to further biomechanical, radiographic imaging, and clinical studies of the importance of these posterior knee structures. [ABSTRACT FROM AUTHOR]

This paper examines some of the problems and questions that must be considered in relation to research on the role of growth factors in preimplantation embryos. It reviews and summarizes the large body of work on gene expression of growth factor receptors and ligands in preimplantation embryos and in oviduct and uterine tissue. It also reviews the literature on the effects of gene knockout in preimplantation embryos and concludes with a review of work on the effects of growth factors on cultured embryos. [ABSTRACT FROM AUTHOR]

Introduction: Clopidogrel hyperresponsiveness is a timely topic, with wide ranging reports of hemorrhagic complications, using various clopidogrel dosing strategies following neuroendovascular procedures. This study serves to investigate hemorrhagic complications using standard clopidogrel doses and timing of these complications in relation to the procedure. Materials and Methods: Retrospective cohort of consecutive adult patients undergoing flow diversion with Pipeline Embolization Device (PED) at an academic medical center, receiving on-label clopidogrel doses. Patients with clopidogrel hyperresponsiveness (VerifyNow TM P2Y12 reaction unit (PRU) ≤ 70) were compared to those who were normoresponsive. The primary outcome is the rate of hemorrhagic complications between groups. Results: Of 148 included patients, 54 (36.5%) were identified as clopidogrel hyperresponsive (PRU ≤ 70) and 94 (63.5%) as clopidogrel normoresponsive (PRU 71 - 194). There were no hemorrhagic complications observed in patients who were clopidogrel hyperresponsive, with 5 occurring in patients who were normoresponsive ( P = 0.09). Three (60%) of the hemorrhages were intracranial with most occurring intra-procedure or within the first week of the procedure. Age > 60 years was the only candidate predictor for hemorrhagic complications ( P = 0.004). Conclusion: Our findings are contradictory, with lower hemorrhagic complications in clopidogrel hyperresponders than prior literature, and most occurring intra-op or in the immediate acute post-op phase., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: The spine, hip, and knee are anatomically and biomechanically connected. Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are commonly employed to treat degenerative changes in the hip and knee, while fusion is used for spine degeneration. Spine deformity correction results in changes in sagittal alignment and pelvic parameters, and patients with stiff spines have higher rates of THA dislocation and revision due to instability. The goal of this study was to determine the prevalence of total joint arthroplasty (TJA) in adult spinal deformity (ASD) patients at our institution., Methods: Following Institutional Review Board approval, we retrospectively reviewed a list of cases performed by the senior author from 4/2017 to 5/2021. Patients > 18 years old undergoing preoperative evaluation for symptomatic lumbar degeneration or ASD were included. Patients < 18 years old, those diagnosed with adolescent idiopathic scoliosis, and non-fusion cases were excluded. Perioperative full-length standing EOS images were examined for the presence or absence of THA, TKA, or both. Demographic data was collected from patient electronic medical records, and statistical analyses were completed., Results: 572 consecutive cases were reviewed, and 322 were excluded. 250 cases (97M:153F) were included in the final analysis, with a mean age of 61.8 ± 11.2 years. A total of 74 patients had a TJA (29.4%). THA was present in 41 patients (16.4%), and TKA was present in 49 patients (19.6%). Males had a higher prevalence of TJA, THA, and TKA (29.9%, 16.5%, and 21.6%) than females (29.4%, 16.3%, and 18.3%)., Conclusions: This study revealed a high prevalence TJA rate of 29.4% in ASD at our institution. This rate surpasses the prevalence rate reported among the general population in previous studies. High prevalence of patients with ASD and TJA may merit special surgical consideration., (© 2024. The Author(s), under exclusive licence to Scoliosis Research Society.)

Background: In 2005, the Food and Drug Administration placed a black-box warning (the most stringent warning for drugs) on all nonaspirin nonsteroidal anti-inflammatory drugs (NSAIDs) stating that these agents may cause heart attacks and/or strokes. No level I evidence demonstrates that nonselective NSAIDs increase cardiovascular risk. An alternative hypothesis is that hip and knee osteoarthritis (OA) indirectly causes cardiovascular disease (CVD) through decreased activity and NSAIDs are correlated with CVD as an arthritis treatment., Methods: Systematic reviews were conducted to find observational studies evaluating the association of hip and/or knee OA, CVD, activity, walking, and step counts. The systematic review found studies correlating hip and/or knee OA and CVD morbidity incidence (n = 2); CVD morbidity prevalence (n = 6); odds ratios, relative risks, or hazard ratios of CVD morbidity (n = 11); relative risk, standardized mortality ratios, or hazard ratios of CVD mortality (n = 14); and all-cause mortality hazard ratios associated with NSAID use (n = 3)., Results: Hip OA (5 studies), knee OA (9 studies), and hip and knee OA (6 studies) are linked to an increased risk of CVD morbidity and mortality. Cardiac risk increases with validated disability scores, use of walking aids, walking difficulties, longer follow-up times, younger ages of OA onset, numbers of joints involved, and OA severities. No study linked NSAID use to cardiac disease., Conclusions: All studies with more than 10-year follow-up linked cardiac disease with hip and knee OA. No study linked nonselective NSAID use to CVD. The Food and Drug Administration should reconsider the black-box warnings on naproxen, ibuprofen, and celecoxib., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Glutathione-capped copper sulfide (Cu x S y ) nanoparticles with two different average sizes were successfully achieved by using a simple reduction process that involves only changing the reaction temperature. Temperature-induced changes in the size of Cu x S y nanoparticles resulted in particles with different optical, morphological, and electrochemical properties. The dependence of electrochemical sensing properties on the sizes of Cu x S y nanoparticles was studied by using voltammetric and amperometric techniques. The spherical Cu x S y nanoparticles with the average particle size of 25 ± 0.6 nm were found to be highly conductive as compared to Cu x S y nanoparticles with the average particle size of 4.5 ± 0.2 nm. The spherical Cu x S y nanoparticles exhibited a low bandgap energy (E g ) of 1.87 eV, resulting in superior electrochemical properties and improved electron transfer during glucose detection. The sensor showed a very good electrocatalytic activity toward glucose molecules in the presence of interference species such as uric acid (UA), ascorbic acid (AA), fructose, sodium chloride, and sucrose. These species are often present in low concentrations in the blood. The sensor demonstrated an excellent dynamic linear range between 0.2 to 16 mM, detection limit of 0.2 mM, and sensitivity of 0.013 mA/mM. The applicability of the developed sensor for real field determination of glucose was demonstrated by use of spiked blood samples, which confirmed that the developed sensor had great potential for real analysis of blood glucose levels.

A diaryl ketone series was identified as vanin-1 inhibitors from a high-throughput screening campaign. While this novel scaffold provided valuable probe 2 that was used to build target confidence, concerns over the ketone moiety led to the replacement of this group. The successful replacement of this moiety was achieved with pyrimidine carboxamides derived from cyclic secondary amines that were extensively characterized using biophysical and crystallographic methods as competitive inhibitors of vanin-1. Through optimization of potency and physicochemical and ADME properties, and guided by co-crystal structures with vanin-1, 3 was identified with a suitable profile for advancement into preclinical development.

Objective: Alcohol use disorder (AUD) is a leading cause of global disease burden. Chronic, heavy use increases the likelihood of alcohol withdrawal symptoms and associated secondary outcomes of alcohol craving and mood, anxiety, and sleep disturbances, which are predictive of poor treatment outcomes. The authors examined whether alcohol withdrawal symptoms moderate the efficacy of prazosin in reducing alcohol intake and associated secondary outcomes., Methods: A 12-week, double-blind, randomized, controlled proof-of-concept trial of prazosin (16 mg/day, with a 2-week titration) was conducted in community-recruited adults with current alcohol dependence (N=100) with varying levels of alcohol withdrawal symptoms assessed at treatment entry. Primary outcomes were daily self-reported drinking days and heavy drinking days, and secondary outcomes were average drinks/day and mood, anxiety, craving, and sleep quality ratings., Results: Modified intent-to-treat analyses indicated a significant interaction of alcohol withdrawal symptom score by treatment by full-dose treatment period (weeks 3-12) for drinking days, heavy drinking days, and average drinks/day. By week 12, participants with high alcohol withdrawal symptoms on prazosin reported 7.07% heavy drinking days and 27.46% drinking days, while those on placebo had 35.58% heavy drinking days and 58.47% drinking days (heavy drinking days: odds ratio=0.14, 95% CI=0.058, 0.333; drinking days: odds ratio=0.265, 95% CI=0.146, 0.481). No such benefit of prazosin was observed in those reporting low or no alcohol withdrawal symptoms. Individuals with high alcohol withdrawal symptoms on prazosin compared with placebo also showed significantly improved anxiety, depression, and alcohol craving over the course of the trial., Conclusions: The findings indicate that alcohol withdrawal symptoms are a significant moderator of prazosin treatment response for alcohol use outcomes and for associated symptoms of alcohol craving, anxiety, and mood symptoms. These data support further evaluation of alcohol withdrawal symptoms as a prognostic indicator of prazosin's efficacy in the treatment of AUD.

Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest.

Typical recreational water risk to swimmers is assessed using epidemiologically derived correlations by means of fecal indicator bacteria (FIB). It has been documented that concentrations of FIB do not necessarily correlate well with protozoa and viral pathogens, which pose an actual threat of illness and thus sometimes may not adequately assess the overall microbial risks from water resources. Many of the known pathogens have dose-response relationships; however, measuring water quality for all possible pathogens is impossible. In consideration of a typical freshwater receiving secondarily treated effluent, we investigated the level of consistency between the indicator-derived correlations and the sum of risks from six reference pathogens using a quantitative microbial risk assessment (QMRA) approach. Enterococci and E. coli were selected as the benchmark FIBs, and norovirus, human adenovirus (HAdV), Campylobacter jejuni, Salmonella enterica, Cryptosporidium spp., and Giardia spp. were selected as the reference pathogens. Microbial decay rates in freshwater and uncertainties in exposure relationships were considered in developing our analysis. Based on our exploratory assessment, the total risk was found within the range of risk estimated by the indicator organisms, with viral pathogens as dominant risk agents, followed by protozoan and bacterial pathogens. The risk evaluated in this study captured the likelihood of gastrointestinal illnesses only, and did not address the overall health risk potential of recreational waters with respect to other disease endpoints. Since other highly infectious pathogens like hepatitis A and Legionella spp. were not included in our analysis, these estimates should be interpreted with caution.

Background and Purpose- It is unknown whether noncontrast computed tomography (NCCT) can identify patients who will benefit from intra-arterial treatment (IAT) in the extended time window. We sought to characterize baseline Alberta Stroke Program Early CT Score (ASPECTS) in DAWN (DWI or CTP Assessment With Clinical Mismatch in the Triage of Wake-Up and Late Presenting Strokes Undergoing Neurointervention With Trevo) and to assess whether ASPECTS modified IAT effect. Methods- Core lab adjudicated ASPECTS scores were analyzed. The trial cohort was divided into 2 groups by qualifying imaging (computed tomography versus magnetic resonance imaging). ASPECTS-by-treatment interaction was tested for the trial coprimary end points (90-day utility-weighted modified Rankin Scale (mRS) score and mRS, 0-2), mRS 0 to 3, and ordinal mRS. ASPECTS was evaluated separately as an ordinal and a dichotomized (0-6 versus 7-10) variable. Results- Of 205 DAWN subjects, 123 (60%) had NCCT ASPECTS, and 82 (40%) had diffusion weighted imaging ASPECTS. There was a significant ordinal NCCT ASPECTS-by-treatment interaction for 90-day utility-weighted mRS (interaction P=0.04) and mRS 0 to 2 (interaction P=0.02). For both end points, IAT effect was more pronounced at higher NCCT ASPECTS. The dichotomized NCCT ASPECTS-by-treatment interaction was significant only for mRS 0 to 2 (interaction P=0.04), where greater treatment benefit was seen in the ASPECTS 7 to 10 group (odds ratio, 7.50 [2.71-20.77] versus odds ratio, 0.48 [0.04-5.40]). A bidirectional treatment effect was observed in the NCCT ASPECTS 0 to 6 group, with treatment associated with not only more mRS 0 to 3 outcomes (50% versus 25%) but also more mRS 5 to 6 outcomes (40% versus 25%). There was no significant modification of IAT effect by diffusion weighted imaging ASPECTS. Conclusions- Baseline NCCT ASPECTS appears to modify IAT effect in DAWN. Higher NCCT ASPECTS was associated with greater benefit from IAT. No treatment interaction was observed for diffusion weighted imaging ASPECTS.

Objective: Children with special health care needs or chronic conditions are more likely to have unmet health needs than other children. The purpose of this study was to use a community engagement research strategy to assess the essential elements of care coordination that can serve as the foundation for a system-wide care coordination model for children with special health care needs., Study Design: As part of a summit designed to review the status of pediatric care coordination within the state of Arizona and a call to action, a qualitative descriptive study was conducted to solicit anonymous feedback from 104 stakeholders (family, health care provider, or community entity) on the strengths and areas of improvement in the current system that provides care to Arizona children with special health care needs. Data were analyzed using inductive content analysis., Results: Five essential categories crucial to building an effective and seamless care coordination model were extracted from the data: Communication, Insurance, Health Care Capacity, Provider Knowledge, and Family Education., Conclusions: The results from this study can serve as the working foundation to build a system-wide model for pediatric care coordination throughout the state. Providing care coordination services involves many activities across a wide range of organizations and locations. Research that is inclusive of community stakeholders can determine essential components for building a foundation for care coordination., (Published by Elsevier Inc.)

Context: Postural stability is the ability to control the center of mass in relation to a person's base of support and can be affected by both musculoskeletal injury and traumatic brain injury. The NeuroCom Sensory Organization Test (SOT) can be used to objectively quantify impairments to postural stability. The ability of postural stability to predict injury and be used as an acute injury-evaluation tool makes it essential to the screening and rehabilitation process. To our knowledge, no published normative data for the SOT from a healthy, highly active population are available for use as a reference for clinical decision making., Objective: To present a normative database of SOT scores from a US Military Special Operations population that can be used for future comparison., Design: Cross-sectional study., Setting: Human performance research laboratory., Patients or Other Participants: A total of 542 active military operators from Naval Special Warfare Combatant-Craft Crewmen (n = 149), Naval Special Warfare Command, Sea, Air, and Land (n = 101), US Army Special Operations Command (n = 171), and Air Force Special Operations Command (n = 121)., Main Outcome Measure(s): Participants performed each of the 6 SOT conditions 3 times. Scores for each condition, total equilibrium composite score, and ratio scores for the somatosensory, visual, and vestibular systems were recorded., Results: Differences were present across all groups for SOT conditions 1 (P < .001), 2 (P = .001), 4 (P > .001), 5 (P > .001), and 6 (P = .001) and total equilibrium composite (P = .000), visual (P > .001), vestibular (P = .002), and preference (P > .001) NeuroCom scores., Conclusions: Statistical differences were evident in the distribution of postural stability across US Special Operations Forces personnel. This normative database for postural stability, as assessed by the NeuroCom SOT, can provide context when clinicians assess a Special Operations Forces population or any other groups that maintain a high level of conditioning and training.

Background: Most patients have favorable outcomes after primary total knee arthroplasty (TKA). Well-validated methods to predict the risk of poor outcomes have not been developed or implemented. Several patients have annual clinic visits despite well-funcitoning TKA, as a routine practice, to detect early failure requiring revision surgery. It is not known whether assessment of pain and function can be used as a predictive tool for early failure and revision to guide practice. Our objective was to determine whether pain and function can predict revision after TKA., Methods: We retrospectively studied data from a large prospectively gathered TKA registry to examine changes in outcome scores for primary TKAs undergoing revision compared to those not requiring revision to determine the factors that are predictive for revision., Results: Of the 1,012 patients, 721 had had a single-sided primary TKA and had American Knee Society (AKS) Scores for three or more visits. 46 patients underwent revision, 23 acutely (fracture, traumatic component failure or acute infection) and 23 for latent causes (late implant loosening, progressive osteolysis, or pain and indolent infection). Mean age was 70 years for the non-revision patients, and 64 years for those revised. Both AKS Clinical and AKS Function Scores for non-revised patients were higher than in revision patients, higher in acute revision compared to latent revision patients. Significant predictors of revision surgery were preoperative, 3- and 15-month postoperative AKS Clinical Scores and 3-month AKS Function Scores. At 15-month post-TKA, a patient with a low calculated probability of revision, 32 % or less, was unlikely to require revision surgery with a negative predictive value of 99 %., Conclusion: Time dependent interval evaluation post-TKA with the AKS outcome scores may provide the ability to assign risk of revision to patients at the 15-month follow-up visit. If these findings can be replicated using a patient-reported measure, a virtual follow-up with patient-reported outcomes and X-ray review may be an alternative to clinic visit for patients doing well.

After decades of research and development on fabrication of efficient light-emitting diodes (LEDs) throughout the visible spectrum, LED-based lighting has reached unparalleled performance with respect to energy efficiency and has become the light source for virtually all new lighting products being designed today. The development of the core light sources and their subsequent integration into lighting systems continue to present unique challenges and opportunities for product designers. We review these systems and the current development status, as well as provide context for the trends in solid state lighting that are leading to the development of value-added lighting solutions that extend the domain of lighting beyond light generation, into fields as diverse as communications, healthcare, and agricultural production.

First responders are exposed to various types of disasters throughout their career. Because of their roles, they are often regarded as stronger people than individuals from other occupations. A systematic review of literature was conducted to determine if distinct characteristics exist that make first responders more susceptible to psychological trauma. Five categories of traits were found to put first responders at risk for psychological problems: personal, predisposing, peridisposing, postdisposing, and protective. To counteract the impact of psychological trauma, first responders need additional preincident psychological and resiliency training. Preparedness and awareness will help combat psychological impact from disasters and compassion fatigue.

Background: The US Naval Special Warfare's Special Warfare Combatant-Craft Crewmen (SWCC) operate on small, high-speed boats while wearing tactical gear (TG). The TG increases mission safety and success but may affect postural stability, potentially increasing risk for musculoskeletal injury. Therefore, the purpose of this study was to examine the effects of TG on postural stability during the Sensory Organization Test (SOT)., Methods: Eight SWCC performed the SOT on NeuroCom's Balance Manager with TG and with no tactical gear (NTG). The status of gear was performed in randomized order. The SOT consisted of six different conditions that challenge sensory systems responsible for postural stability. Each condition was performed for three trials, resulting in a total of 18 trials., Results: Overall performance, each individual condition, and sensory system analysis (somatosensory, visual, vestibular, preference) were scored. Data were not normally distributed therefore Wilcoxon signed-rank tests were used to compare each variable (ρ = .05). No significant differences were found between NTG and TG tests. No statistically significant differences were detected under the two TG conditions. This may be due to low statistical power, or potentially insensitivity of the assessment. Also, the amount and distribution of weight worn during the TG conditions, and the SWCC's unstable occupational platform, may have contributed to the findings. The data from this sample will be used in future research to better understand how TG affects SWCC., Conclusion: The data show that the addition of TG used in our study did not affect postural stability of SWCC during the SOT. Although no statistically significant differences were observed, there are clinical reasons for continued study of the effect of increased load on postural stability, using more challenging conditions, greater surface perturbations, dynamic tasks, and heavier loads., (2016.)

The interface interactions between surfactants oleic acid and oleylamine and magnetic nanoparticles are studied via molecular mechanics and dynamics. Mixtures of these two surfactants are widely advocated in the chemical synthesis of nanoparticles. However, the exact dynamic mechanism remains unclear. Here we report, for the first time, a comprehensive qualitative model showing the importance of acid-base complex formation between oleic acid and oleylamine as well as the presence of free protons in the engineering of nanoparticles of specific shapes and sizes. We show why critical parameters such as surfactant concentration may modify iron oxide nanoparticle shape and size and how this can be understood in the light of acid-base complex pair formation. We report on the influence these parameters have on both the in situ nanoparticle surface charge and zeta potential. Transmission electron microscopy (TEM), FTIR, and pH studies are used to confirm the validity of the calculated binding energies and number of acid-base pairs.

Magnetic nanoparticles with tailored surface chemistry are widely used for a number of different in vivo applications, ranging from tissue repair and magnetic cell separation through to cancer-hyperthermia, drug delivery and magnetic resonance imaging contrast enhancement. A major requirement for all these biomedical applications is that these nanoparticles must have high magnetization values and sizes smaller than 100 nm with a narrow particle size distribution. Thus nanoparticles must have uniform physical and chemical properties. For these applications, a tailored surface coating/shell needs to be engineered, which has to be non-toxic, biocompatible and make allowance for targetable drug delivery with particle localization in a targeted area. Most work in this field has been done on improving the biocompatibility of the nanoparticles. Only a few scientific investigations have been carried out on improving the quality of magnetic nanoparticles with specific focus on the nanoparticle's surface chemistry, size distribution and shape (which directly influences the magnetic properties). All these particles also need to be properly characterized in order to get a protocol for the quality control of these particles, the nature of the surface coatings and their subsequent geometric arrangement. This will ultimately determine the overall size of the colloids and also plays a significant role in biokinetics and biodistribution of nanoparticles in the body. This review highlights recent advances in the synthetic chemistry, magnetic characterization and biological applications of inorganic/organic - core/shell FexOy based magnetic nanoparticles with specific focus on using the two popular surfactants for producing MNPs namely oleic acid and/or oleylamine as capping agents. Although the main nano-magnets under discussion are magnetite (Fe3O4) nanoparticles, maghemite (γ-Fe2O3) is also briefly mentioned.

Flotation restricted environmental stimulation technique (REST) involves compromising senses of sound, sight, and touch by creating a quiet dark environment. The individual lies supine in a tank of Epsom salt and water heated to roughly skin temperature (34-35° C). This study was performed to determine if a 1-hour flotation REST session would aid in the recovery process after maximal eccentric knee extensions and flexions. Twenty-four untrained male students (23.29 ± 2.1 years, 184.17 ± 6.85 cm, 85.16 ± 11.54 kg) participated in a randomized, repeated measures crossover study. The participants completed 2 exercise and recovery protocols: a 1-hour flotation REST session and a 1-hour seated control (passive recovery). After isometric muscle strength testing, participants were fatigued with eccentric isokinetic muscle contractions (50 repetitions at 60°·s) of the nondominant knee extensors and flexors. Blood lactate, blood glucose, heart rate, OMNI-rating of perceived exertion for resistance exercise (OMNI-RPE), perceived pain, muscle soreness, and isometric strength were collected before exercise, after treatment, and 24 and 48 hours later. A multivariate analysis of covariance found that treatment had a significant main effect on blood lactate, whereas subsequent univariate analyses of variance found statistical significance with the immediate posttreatment blood lactate measures. The results indicate that flotation REST appears to have a significant impact on blood lactate and perceived pain compared with a 1-hour passive recovery session in untrained healthy men. No difference was found between conditions for muscle strength, blood glucose, muscle soreness, heart rate, or OMNI-RPE. Flotation REST may be used for recreational and professional athletes to help reduce blood lactate levels after eccentric exercise.

Symptomatic sacroiliac (SI) joint disease is poorly understood. The literature provides no clear aetiology for SI joint pathology, making evaluation and diagnosis challenging. We hypothesised that patients with documented sacroiliac pain might provide insight into the aetiology of these symptoms. Specifically, we questioned whether SI joint symptoms might be associated with abnormal hip radiographs. We reviewed the pelvic and hip radiographs of a prospectively collected cohort of 30 consecutive patients with SI joint pathology. This database included 33 hips from 30 patients. Radiographic analysis included measurements of the lateral centre edge angle, Tönnis angle, and the triangular index, of the ipsilateral hip. Evidence for retrotorsion of the hemipelvis was recorded. Hips were graded on the Tönnis grading system for hip arthrosis. In this cohort 14/33 (42%) of hips had evidence of significant osteoarthrosis indicated by Tönnis grade 2 or greater and 15/33 (45%) displayed subchondral cyst formation around the hip or head neck junction. In assessing acetabular anatomy, 21% (7/33) had retroversion, 12% (4/33) had a lateral centre edge angle >40° with 3% (1/33) >45°. Tönnis angle was <0° in 27% (9/33). Coxa profunda and acetabuli protrusio were present in 47% (17/33) and 3% (1/33), respectively. When femoral head morphology was assessed, 33% (11/33) showed evidence of cam impingement. Overall, 76% (25/33) had at least one abnormality on their hip radiograph. A significant number of patients meeting strict diagnostic criteria for SI joint pain had radiographic evidence of femoroacetabular impingement (FAI) and hip arthrosis. The clinician should maintain FAI in the differential diagnosis when investigating patients with buttock pain.

Background: Radiographic evaluation of the hip is extremely important in the diagnosis and treatment decisionmaking process for pre-arthritic hip disease. Many different radiographic measurements have been described as indicators of underlying structural hip deformity. The purpose of this study was to determine the interobserver and intraobserver reliability of various musculoskeletal physicians in performing selected measurements of adult structural hip anatomy., Methods: A blinded review of 45 sets of radiographs from patients with developmental dysplasia, femoro-acetabular impingement, and normal anatomy was performed. Data points included the lateral center-edge angle (LCEA), vertical-center-anterior angle (VCA), head-neck offset ratio (UNO), alpha angle, Tönnis angle, Tönnis osteoarthritis grade and a radiographic diagnosis. One orthopaedic fellow, two orthopaedic residents, and two attending musculoskeletal physiatrists analyzed radiographs on two separate occasions. One sports medicine orthopaedic attending physician completed a single analysis of the image sets. Intraobserver and interobserver reliability was established using intra-class correlation coefficients (ICC) for continuous variables. Agreement regarding categorical variables was performed using the kappa coefficient, Results: Excellent intraobserver reliability was found for the following: LCEA (ICC = 0.88), VCA (0.88), Tönnis angle (0.83), HNO on the frog lateral (0.78), alpha angle on the frog lateral (0.76), HNO on the cross-table lateral (0.75), and angle alpha on the cross-table lateral (0.76). Intraobserver reliability for osteoarthritis grade was poor (weighted kappa = 0.57). For all data points, interobserver reliability was considerably worse, with 95% confidence intervals spanning below 0.55., Conclusions: While the described measurements of adult structural hip anatomy provide excellent reliability for a given reader, these measurements are less reliable across readers. Taken in isolation, these measurements, as performed by observers with varied clinical experience and clinical backgrounds, are limited in determining a consistent radiographic diagnosis.

Background: Ligament restraints to terminal knee extension are poorly understood., Hypotheses: (1) As with other motions of the knee, genu recurvatum is limited primarily by a named, identifiable structure. (2) As the largest static structure of the posterior knee, the oblique popliteal ligament is uniquely suited to act as a checkrein to knee hyperextension., Study Design: Descriptive laboratory study., Methods: Twenty fresh-frozen human knees were divided into 3 groups for a ligament sectioning study. Extension moments of 14 and 27 N x m were applied before and after sectioning of each ligament, and motion changes were recorded. In group 1, the oblique popliteal ligament was sectioned first, followed by the fabellofibular ligament, ligament of Wrisberg, anterior cruciate ligament, posterolateral structures, and posterior cruciate ligament. In group 2, the order was altered to section the anterior cruciate ligament first; no other changes were made. Similarly, the cutting order for group 3 was altered to section the posterior cruciate ligament first. The sagittal tibial slope of each specimen was documented off a lateral radiograph., Results: The greatest increase in knee hyperextension was observed after sectioning the oblique popliteal ligament. This was independent of cutting order, consistent across groups, and statistically significant. In all groups, the increase in knee hyperextension after sectioning the oblique popliteal ligament approached or exceeded the increases seen after sectioning the anterior and posterior cruciate ligaments combined. Overall, less knee hyperextension was seen in knees with increased posterior tibial slope., Conclusion: The oblique popliteal ligament was found to be the primary ligamentous restraint to knee hyperextension., Clinical Relevance: Further studies are needed to determine if surgical repair or reconstruction of the oblique popliteal ligament can restore normal motion limits in patients with symptomatic genu recurvatum. Patients with decreased posterior tibial slope would have increased recurvatum with posterior structure injury, which increases the likelihood of increased symptoms in this population.

Unlabelled: Prophylactic antibiotics are frequently withheld until cultures are obtained in revision total knee arthroplasty (TKA). We undertook a prospective study to determine whether prophylactic preoperative intravenous antibiotics would affect the results of cultures obtained intraoperatively. We enrolled 25 patients with 26 infected TKAs, a known preoperative infecting organism, and no recent antibiotic therapy. Reaspiration of the infected TKA was performed after anesthesia and sterile preparation. Intravenous antibiotic prophylaxis was then administered and the tourniquet inflated. Intraoperative culture swabs and tissue were obtained at arthrotomy. The timing of events was recorded. Pre- and postantibiotic culture data were analyzed to determine the effect of intravenous preoperative prophylactic antibiotics on cultures obtained intraoperatively. Infections were acute postoperative (four), chronic (19), and acute hematogenous (three). The most common infecting organism was cloxacillin-sensitive Staphylococcus aureus (nine knees [35%]). Preoperative prophylactic antibiotics did not affect the results of intraoperative cultures and we therefore believe should not be withheld before surgery for an infected TKA when an organism has been identified on aspiration preoperatively, and there has been no recent (4 weeks) antimicrobial therapy., Level of Evidence: Level II, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

Background: The accurate preoperative diagnosis of infection is an essential component of decision-making prior to revision total knee arthroplasty. When preoperative modalities used to detect infection reveal equivocal findings, the surgeon may rely on intraoperative testing. While intraoperative Gram stains are routinely performed during revision total knee arthroplasty, their value remains unclear., Methods: We retrospectively reviewed the records on 945 revision total knee arthroplasties performed at three university institutions to which patients were referred for total joint arthroplasty; the results of an intraoperative Gram stain were available for review in 921 cases (97.5%). Of these knees, 247 were classified as infected on the basis of (1) the presence of the same organism in two cultures; (2) growth, on solid media, of an organism as well as other objective evidence of infection; (3) histologic evidence of acute inflammation; (4) gross purulence; and/or (5) an actively draining sinus. We reviewed the results of preoperative laboratory studies, which included measurements of the erythrocyte sedimentation rate, C-reactive protein values, and white blood-cell count in 90%, 76%, and 98% of cases, respectively. Preoperative aspiration to obtain a specimen for culture and a cell count was performed routinely at one center and selectively at the other two centers, and the results were available for review in 439 (48%) of the 921 cases., Results: Intraoperative Gram staining was found to have a sensitivity of 27% and a specificity of 99.9%. The positive and negative predictive values were 98.5% and 79%, respectively. The test accuracy was 80%. Patients with a true-positive Gram stain had a significantly higher preoperative white blood-cell count, C-reactive protein level, and nucleated cell count in the aspirate when compared with patients with a false-negative Gram stain (p < 0.001). In no case did the results of the intraoperative Gram stain alter treatment., Conclusions: The intraoperative Gram stain was found to have poor sensitivity and a poor negative predictive value, and its results did not alter the treatment of any patient undergoing revision total knee arthroplasty because of a suspected infection. These data do not support the routine use of intraoperative Gram staining in revision total knee arthroplasty; instead, they suggest a much more limited role for this test.

Unlabelled: A wide variation exists in rehabilitation after total hip arthroplasty (THA) in part due to a paucity of evidence-based literature. We asked whether a minimally invasive surgical approach, a multimodal approach to pain control with revised anesthesia protocols, hip restrictions, or preoperative physiotherapy achieved a faster rehabilitation and improved immediate short-term outcome. We conducted a systematic review of 16 level I and II studies after a strategy-based search of English literature on OVID Medline, PubMed, CINAHL, Cochrane, and EMBASE databases. We defined the endpoint of assessment as independent ambulation and ability to perform activities of daily living. Literature supports the use of a multimodal pain control to improve patient compliance in accelerated rehabilitation. Multimodal pain control with revised anesthesia protocols and accelerated rehabilitation speeds recovery after minimally invasive THA compared to the standard approach THA, but a smaller incision length or minimally invasive approach does not demonstrably improve the short-term outcome. Available studies justify no hip restrictions following an anterolateral approach but none have examined the question for a posterior approach. Preoperative physiotherapy may facilitate faster postoperative functional recovery but multicenter and well-designed prospective randomized studies with outcome measures are necessary to confirm its efficacy., Level of Evidence: Level II, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

The need for rapid methods to accurately detect methicillin-resistant Staphylococcus aureus (MRSA) is widely acknowledged, and a number of molecular assays are commercially available. This study evaluated the Xpert MRSA assay, which is run on the GeneXpert real-time PCR platform (Cepheid) for use in a clinical laboratory. The following parameters were investigated: (i) the limits of detection (LoDs) for four MRSA strains; (ii) the ability to detect isolates of MRSA from a collection representative of MRSA in Ireland since 1974 (n = 114) and the ability to detect control strains with staphylococcal cassette chromosome mec types IVa (IV.1.1.1), IVb (IV.2.1.1), IVc (IV.3.1.1), IVd (IV.4.1.1), V (V.1.1.1), V(T), and VI; and (iii) performance in a clinical trial with swabs from nose, throat, and groin/perineum sites from 204 patients, where results were compared with those obtained by direct and enrichment cultures. The average LoD of the four test strains was 610 CFU/ml (equivalent to 58 CFU/swab). All 114 MRSA isolates and 7 control strains tested were detected. Sensitivity, specificity, and positive and negative predictive values for clinical specimens from all sites investigated were 90%, 97%, 86%, and 98%, respectively, but throat specimens yielded poor sensitivity (75%). Sensitivity, specificity, and positive and negative predictive values for nasal specimens were 95%, 98%, 90%, and 99%, respectively. Overall, the assay was rapid and easy to perform, but performance might be enhanced by the inclusion of an equivocal interpretive category based on analysis of all available amplification data.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) carrying pvl is an emerging problem worldwide. CA-MRSA tends to harbor staphylococcal cassette chromosome mec type IV (SCCmec IV), to be non-multiantibiotic resistant, and to have different genotypes from the local hospital-acquired MRSA (HA-MRSA). However, in Ireland, 80% of HA-MRSA isolates have the non-multiantibiotic-resistant genotype ST22-MRSA-IV. This study investigated MRSA isolates from Ireland (CA-MRSA, health care-associated MRSA, and HA-MRSA) for the carriage of pvl and determined the genotypic characteristics of all pvl-positive isolates identified. All 1,389 MRSA isolates were investigated by antibiogram-resistogram typing and SmaI DNA macrorestriction analysis. pvl-positive isolates were further characterized by multilocus sequence typing and SCCmec, agr, and toxin gene typing. Twenty-five (1.8%) MRSA isolates belonging to six genotypes (ST30, ST8, ST22, ST80, ST5, and ST154) harbored pvl. Nineteen of these (76%) were CA-MRSA isolates, but a prospective study of MRSA isolates from 401 patients showed that only 6.7% (2/30) of patients with CA-MRSA yielded pvl-positive isolates. Thus, pvl cannot be used as a sole marker for CA-MRSA. Fifty-two percent of pvl-positive MRSA isolates were recovered from patients with skin and soft tissue infections; thirty-six percent were from patients of non-Irish ethnic origin, reflecting the increasing heterogeneity of the Irish population due to immigration. All 25 pvl-positive isolates carried SCCmec IV; 14 (56%) harbored SCCmec IV.1 or IV.3, and the remaining 11 isolates could not be subtyped. This study demonstrates that pvl is not a reliable marker for CA-MRSA in Ireland and reveals the emergence and importation of diverse genotypes of pvl-positive MRSA in Ireland.

Rapid accurate detection is a prerequisite for the successful control of meticillin-resistant Staphylococcus aureus (MRSA). The IDI-MRSA real-time polymerase chain reaction (PCR) assay was designed to provide rapid results from nasal specimens collected in Stuart's liquid transport medium. This study has evaluated the IDI-MRSA kit for use in a clinical laboratory by investigating the following parameters: (1) limits of detection (LoD), (2) performance with Amies' gel-based transport medium, (3) ability to detect strains of MRSA in a collection representative of MRSA in Ireland since 1974 (n=113) and (4) performance in a clinical trial with swabs from nose, throat and groin/perineum sites from 202 patients. LoDs (colony-forming units per ml) of the IDI-MRSA kit, direct culture on MRSA-Select chromogenic agar (CA) and salt-enrichment culture (with subculture onto CA) were 10(3), 10(3) and 10(2), respectively. LoDs with Stuart's and Amies' transport media were comparable. All except one of the 113 MRSA isolates were detected by the kit but, when six control strains carrying staphylococcal cassette chromosome mec (SCCmec) type IV element subtypes IVa-d and SCCmec types V and V(T) were tested, the kit failed to detect MRSA carrying SCCmec V. The sensitivity and specificity for detection of MRSA from nose, throat and groin/perineum specimens were comparable with slightly lower sensitivities from throat and groin/perineum specimens compared with nasal swabs (90%, 97%; 89%, 99%; 88%, 99%, respectively). Overall sensitivity, specificity and positive and negative predictive values for specimens from all sites were 88%, 99%, 94% and 97%, respectively. Further developments to improve the sensitivity of this highly worthwhile assay are required.

The widespread conversion of rural land to low-density residential development poses an immediate threat to biodiversity and to the provision of ecosystem services. Given that development will continue and environmental stakes are high, analyzing alternative growth strategies is critical. Conservation development is one such strategy that has the potential to benefit ecosystems and diverse stakeholders including developers, homebuyers, governments, and society as a whole. Conservation development clusters homes on one part of a property to manage the most ecologically important land for the conservation of biodiversity and ecosystem services. We draw on lessons learned from landscape ecology, open-space development, and regional planning to weigh the biophysical, economic, and institutional evidence for and against conservation development. Conservation development offers many potential environmental and economic advantages: relatively high home values and appreciation rates, lower development costs, and social and ecological benefits to society including landscape connectivity, protection and active stewardship of important ecological assets, and the maintenance of ecosystem services. But this approach also has shortcomings: it may require enlightened institutional regulations and regional planning (and/or ecologically aware developers), it is not always more profitable than conventional development and thus may require subsidies or incentives, and additional research is required to fully understand its benefits and drawbacks. With more information on the effects of clustering, the development of flexible zoning laws, and effective regional planning, conservation development could be a viable strategy for sustaining biodiversity and ecosystem services in changing landscapes.

Between 1999 and 2003, meticillin-resistant Staphylococcus aureus (MRSA) isolates recovered from blood cultures in Irish hospitals that participate in the European Antimicrobial Resistance Surveillance System were investigated by epidemiological typing using antibiogram-resistogram (AR) typing, biotyping, and DNA macrorestriction digestion using SmaI followed by pulsed-field gel electrophoresis (PFGE). PFGE patterns were assigned five-digit pulsed-field type (PFT) numbers, and PFTs of apparently related patterns were abbreviated to two-digit PFT groups (PFGs). AR and PFGE typing results were combined to produce AR-PFG types. Representative isolates of each AR-PFG type recovered in 2002 were typed by multilocus sequence typing and staphylococcal cassette chromosome (SCC) mec analysis. Isolates from 1999 and 2000 were also typed by phage typing. The extent to which epidemiological types of MRSA from blood cultures could be extrapolated to the total MRSA population was investigated by comparing results obtained with isolates from the total MRSA population versus those obtained with blood cultures during three study periods. Over the 5 years from 1999 to 2003, 1,580 blood culture isolates from 1,495 patients were analysed. Typeability and discriminatory indices were as follows: AR typing, 1 and 0.97; phage typing, 0.29 and 0.89; PFGE, 0.99 and 0.95; AR-PFG typing, 1 and 0.95. The most frequently occurring AR-PFG types were 06-01, 07-02, 13-00, and 14-00 and were exhibited by 57, 7, 14, and 12% of isolates, respectively. During the study period, the distribution of AR-PFG type changed markedly, with the prevalence of one type (AR-PFG 06-01) increasing by 880%, from 22% (39/181) in 1999 to 80% (343/430) in 2003. Investigation of whether epidemiological types among blood culture isolates of MRSA were representative of the total MRSA population showed that there was no significant difference in most instances. MLST and SCCmec typing showed that AR-PFG types 06-01, 07-02, 13-00, and 14-00 were ST22-MRSA-IV, ST36-MRSA-II, ST8-MRSA-IID, and ST8-MRSA-IIE, respectively.

L-Ribulose-5-phosphate (L-Ru5P) 4-epimerase and L-fuculose-1-phosphate (L-Fuc1P) aldolase are evolutionarily related enzymes that display 26% sequence identity and a very high degree of structural similarity. They both employ a divalent cation in the formation and stabilization of an enolate during catalysis, and both are able to deprotonate the C-4 hydroxyl group of a phosphoketose substrate. Despite these many similarities, subtle distinctions must be present which allow the enzymes to catalyze two seemingly different reactions and to accommodate substrates differing greatly in the position of the phosphate (C-5 vs C-1). Asp76 of the epimerase corresponds to the key catalytic acid/base residue Glu73 of the aldolase. The D76N mutant of the epimerase retained considerable activity, indicating it is not a key catalytic residue in this enzyme. In addition, the D76E mutant did not show enhanced levels of background aldolase activity. Mutations of residues in the putative phosphate-binding pocket of the epimerase (N28A and K42M) showed dramatically higher values of K(M) for L-Ru5P. This indicates that both enzymes utilize the same phosphate recognition pocket, and since the phosphates are positioned at opposite ends of the respective substrates, the two enzymes must bind their substrates in a reversed or "flipped" orientation. The epimerase mutant D120N displays a 3000-fold decrease in the value of k(cat), suggesting that Asp120' provides a key catalytic acid/base residue in this enzyme. Analysis of the D120N mutant by X-ray crystallography shows that its structure is indistinguishable from that of the wild-type enzyme and that the decrease in activity was not simply due to a structural perturbation of the active site. Previous work [Lee, L. V., Poyner, R. R., Vu, M. V., and Cleland, W. W. (2000) Biochemistry 39, 4821-4830] has indicated that Tyr229' likely provides the other catalytic acid/base residue. Both of these residues are supplied by an adjacent subunit. Modeling of L-Ru5P into the active site of the epimerase structure suggests that Tyr229' is responsible for deprotonating L-Ru5P and Asp120' is responsible for deprotonating its epimer, D-Xu5P.

A mixture of the 8-O-beta-D-glucopyranoside of omega-hydroxyxanthorin 1-O-methyl ether (3) and the 8-O-beta-D-gentiobioside of xanthorin 1-O-methyl ether (4) was isolated from the water-soluble extractives of the Australian toadstool Dermocybe sp. WAT 22963. Compounds 3 and 4 were identified by characterization of their respective peracetyl derivatives 5 and 6.

Immunocytochemical analysis was carried out on samples of 5-, 6-, and 9-week old regenerated soft tissue taken from healing periodontal defects treated by guided tissue regeneration using expanded polytetrafluorethylene (ePTFE) membranes. A panel of monoclonal and polyconal antibodies to cytokeratins, vimentin, and collagen was used to label cells and collagen types I, III, and IV. Epithelium was identified in 7 of the 9 samples examined, in addition to mesenchymal cells staining positively for vimentin and co-distribution of collagen types I, III, and IV in all samples. Clinical observations indicated that exposure of the ePTFE membranes during healing was a frequent occurrence, and the presence and quantity of epithelium found within the healing defect beneath the membrane may be related to the extent to which this occurs.

The protein content of rabbit embryos during the first 7 days of development in vivo was determined. The protein content of intact embryos, embryonic cells (intact embryos without mucin coats for developmental stages up to 96 h post-coitum and free of blastocyst coverings for later stages) and blastocyst coverings were determined by the Pierce Micro BCA assay. The mean protein content of intact one-cell or two-cell embryos was 0.16 micrograms and increased at the four- to six-cell stage with no further increase until the late morula/early blastocyst stages (days 3 to 4). There was a 53-fold increase in protein from the early to late blastocyst stages. The protein content of embryonic cells was stable at a mean value of 0.16 micrograms until the late morula stage (day 3) and then increased to a mean of 6.85 micrograms on day 6 and 50.38 micrograms on day 7. The increase in protein content of intact embryos up to about 72 h appeared to be due solely to an increase in the protein content of the mucin coat. The protein content of the blastocyst coverings increased from a mean of 2 micrograms on day 5 to a mean of 35 micrograms on day 7. For blastocyst stages, the total protein content of intact blastocysts and of embryonic cells was correlated with the surface area of the embryos (r2 = 0.895 and 0.873, respectively) and, thus, an increase in blastocyst size is a true index of blastocyst development.

A factor of low M(r) with growth-promoting effects on rabbit embryos was extracted and purified from commercial bovine serum albumin (BSA). This embryotrophic factor was extracted from BSA dissolved in formic acid by membrane filtration (membrane cutoff of M(r) 10,000) and then freeze-drying of the filtrate. The extract was purified successively by chromatography on G-10 Sephadex, QAE-Sephadex A-25 anion exchange and high-performance liquid chromatography (HPLC) reverse-phase columns. Mass spectrometry of the active reverse-phase material indicated that the major component in this material had an M(r) of 192. The embryotrophic factor in the low M(r) extract of BSA was shown to be citrate, because: (i) the mass spectra of the active reverse-phase material and citrate were identical, (ii) the activity was eluted at the identical position to citrate on an analytical HPLC anion-exchange column, (iii) the original BSA sample was shown by enzyme assay to be heavily contaminated by citrate and (iv) citrate stimulated cell proliferation and expansion of blastocysts.