bluuebunny/crossref_metadata_2025 huggingface dataset:
Antibiotic Prescribing for Children With Nasopharyngitis (Common Colds), Upper Respiratory Infections, and Bronchitis Who Have Health-Professional Parents
Authors: Huang Nicole , Morlock Laura , Lee Cheng-Hua , Chen Long-Shen , Chou Yiing-Jenq
Published: September 2005

Objective. Antibiotic resistance might be reduced if patients could be better informed regarding the lack of benefits of antibiotics for children with viral infections and avoid antibiotic prescriptions in these circumstances. This study investigated whether children having health professionals as parents, a group whose parents are expected to have more medical knowledge and expertise, are less likely than other children to receive antibiotics for nasopharyngitis (common colds), upper respiratory tract infections (URIs), and acute bronchitis.

Methods. Retrospective analyses were conducted by using National Health Insurance data for children of physicians, nurses, pharmacists, and non–health personnel, who had visited hospital outpatient departments or physician clinics for common colds, URIs, and acute bronchitis in Taiwan in 2000. A total of 53733 episodes of care for common colds, URIs, and acute bronchitis in a nationally representative sample of children (aged ≤18 years) living in nonremote areas were analyzed.

Results. The study found that, after adjusting for characteristics of the children (demographic, socioeconomic, and health status) and the treating physicians (demographic, practice style, and setting), children with a physician (odds ratio [OR]: 0.50; 95% confidence interval [CI]: 0.36–0.68) or a pharmacist (OR: 0.69; 95% CI: 0.52–0.91) as a parent were significantly less likely than other children to receive antibiotic prescriptions. The likelihood of receiving an antibiotic for the children of nurses (OR: 0.91; 95% CI: 0.77–1.09) was similar to that for children in the comparison group.

Conclusions. This finding supports our hypothesis that better parental education does help to reduce the frequency of injudicious antibiotic prescribing. Medical knowledge alone, however, may not fully reduce the overuse of antibiotics. Physician-parents, the expected medically savvy parents, can serve as a benchmark for the improvement potentially achievable in Taiwan through a combination of educational, regulatory, communication, and policy efforts targeted at more appropriate antibiotic prescribing in ambulatory settings.
Newborn Hearing Screening in the NICU: Profile of Failed Auditory Brainstem Response/Passed Otoacoustic Emission
Authors: Berg Abbey L. , Spitzer Jaclyn B. , Towers Helen M. , Bartosiewicz Christine , Diamond Beverly E.
Published: September 2005

Objective. Incidence of a specific pattern of auditory responses, absent auditory brainstem responses (ABRs) and present otoacoustic emissions (OAEs), in newborn hearing screening in a regional perinatal center neonatal intensive care unit (NICU) is described. This profile, labeled auditory neuropathy or auditory dyssynchrony (AN/AD), is a dysfunction in neural/brainstem transmission that occurs in individuals whose outer hairs cells are functioning normally. Although the AN/AD profile has been associated with various risk factors, incidence and prediction are unknown.

Method. Analysis of electrophysiologic measures and medical record reviews of the first 22 months of the universal newborn hearing–screening program was conducted. Association of the AN/AD profile was evaluated with the following factors: gender, gestational age, ototoxic drug regimen, low birth weight, hyperbilirubinemia, hydrocephalus, low Apgar score, anoxia, respiratory distress syndrome, pulmonary hypertension, intraventricular hemorrhage, multiple birth, seizure activity, and family history.

Results. One hundred fifteen (24.1%) of the 477 infants failed the ABR in 1 or both ears and passed OAEs bilaterally. Comparisons of infants fitting the AN/AD profile with those not fitting the AN/AD profile were negative with 3 exceptions: those with hyperbilirubinemia and those who were administered vancomycin or furosemide. A logistic-regression analysis model failed to predict which infants would be at risk for the AN/AD profile either unilaterally or bilaterally.

Conclusions. Screening of NICU infants should be conducted with ABR first, followed by OAE after failure on ABR. Because the incidence of the AN/AD profile was found to be 24% in this at-risk population, additional study is warranted.
Does Lidocaine Gel Alleviate the Pain of Bladder Catheterization in Young Children? A Randomized, Controlled Trial
Authors: Vaughan Maureen , Paton Elizabeth A. , Bush Andrew , Pershad Jay
Published: September 2005

Objective. Bladder catheterization (BC) is a commonly performed, painful procedure in the pediatric emergency department (ED). A survey demonstrated that analgesia is infrequently used for several brief painful procedures, including BC, in pediatric patients. In this study, we evaluated the use of 2% lidocaine gel to alleviate the pain associated with BC in young children (<2 years) in the ED.

Methods. We conducted a randomized, double-blind, placebo-controlled trial comparing pain scores during bladder catheterization with 2% lidocaine gel versus nonanesthetic lubricant. We used a previously validated scale for measuring brief procedure-related pain in preverbal children (Face Legs Arms Cry Consolability Pain Scale [FLACC]). A total of 115 patients were recruited; 56 patients were randomized to the control group, and 59 were randomized to the lidocaine group. Lubricant was applied to both the genital mucosa and the catheter. Pain measurements were recorded at 3 time intervals: before insertion of the catheter, during catheterization, and after catheterization. Interobserver reliability had been previously established in an observational pilot study.

Results. The difference in mean FLACC scores between the control (7.55 ± 2.56) and study groups (7.37 ± 2.87) during catheterization was not statistically significant. The change in FLACC from time 1 (preprocedure) to time 2 (during procedure) was statistically significant in both groups, suggesting that bladder catheterization is a painful procedure.

Conclusions. Altering the standard practice of use of nonanesthetic lubricant with 2% lidocaine gel as lubricant during bladder catheterization in young children may not be helpful in alleviating the pain associated with the procedure.
Influence of Photoperiod and Feed Delivery on Growth and Survival of First-Feeding Arctic Char
Authors: Burke M G , Kirk M R , MacBeth N A , Bevan D J , Moccia R D
Published: September 2005

First-feeding Arctic char Salvelinus alpinus were subjected to two different photoperiods (light conditions at latitude 43°28′N [normal] and 24 h of continuous light) and two different feeding schedules (fed only during the natural photoperiod [normal] and 24-h continuous feeding) for 12 weeks. Arctic char subjected to 24 h of continuous light and continuous feed availability had a significantly lower cumulative mortality (P < 0.05) and higher mean final weights (P < 0.05) without an accompanying increase in within-treatment variability compared with fish raised in either ambient photoperiods or under restricted feeding regimens. These results indicate potential commercial benefits associated with extended photoperiod and feeding regimens for the culture of juvenile Arctic char.
Response of Brazos River Oxbow Fish Assemblages to Patterns of Hydrologic Connectivity and Environmental Variability
Authors: Zeug Steven C. , Winemiller Kirk O. , Tarim Soner
Published: September 2005

Three oxbow lakes with different connection frequencies and an adjacent reach of the middle Brazos River, Texas, were surveyed quarterly from summer 1993 to summer 1996 to examine the effects of hydrology and physicochemical attributes on fish assemblage structure. During flood events, oxbows usually were colonized by about 20 fish species from the river channel, and several fluvial specialists were rarely or never sampled from oxbows. Multivariate analyses of seine samples revealed divergent patterns of assemblage structure during periods of isolation that also were associated with a gradient of maximum water depth, temperature, and conductivity. In contrast, analysis of gill‐net samples that targeted large fishes revealed low between‐site and temporal variation in assemblage structure among oxbow lakes but significant differences in the structure of oxbow versus channel assemblages. The shallowest oxbow (which dried out with greatest frequency) had the most variable fish assemblage across seasons and was dominated by small colonizing species, whereas deeper oxbows and the river channel tended to have higher species richness and more stable assemblages. Despite large differences in connection frequency and distance from the river channel, the deepest oxbows had the most similar fish assemblage structure across all seasons. Multiple regression analysis suggested that the timing and frequency of flood events (yielding colonization) in the most frequently connected oxbow interact with predator abundance (yielding mortality) to influence the abundance of common lotic‐adapted minnows (red shiner Cyprinella lutrensis and bullhead minnow Pimephales vigilax) that periodically dominated the species assemblage of that oxbow after floods. Our results suggest that current hydrologic and geomorphologic dynamics in the middle Brazos River produce oxbow lakes with a range of physical characteristics yielding different disturbance and colonization regimes that strongly influence fish species assemblages.
Stringent Regulation of DNA Repair During Human Hematopoietic Differentiation: A Gene Expression and Functional Analysis
Authors: Bracker Tomke U. , Giebel Bernd , Spanholtz Jan , Sorg Ursula R. , Klein-Hitpass Ludger , Moritz Thomas , Thomale Jürgen
Published: September 2005

For the lymphohematopoietic system, maturation-dependent alterations in DNA repair function have been demonstrated. Because little information is available on the regulatory mechanisms underlying these changes, we have correlated the expression of DNA damage response genes and the functional repair capacity of cells at distinct stages of human hematopoietic differentiation. Comparing fractions of mature (CD34−), progenitor (CD34+38+), and stem cells (CD34+38−) isolated from umbilical cord blood, we observed: 1) stringently regulated differentiation-dependent shifts in both the cellular processing of DNA lesions and the expression profiles of related genes and 2) considerable interindividual variability of DNA repair at transcriptional and functional levels. The respective repair phenotype was found to be constitutively regulated and not dominated by adaptive response to acute DNA damage. During blood cell development, the removal of DNA adducts, the resealing of repair gaps, the resistance to DNA-reactive drugs clearly increased in stem or mature compared with progenitor cells of the same individual. On the other hand, the vast majority of differentially expressed repair genes was consistently upregulated in the progenitor fraction. A positive correlation of repair function and transcript levels was found for a small number of genes such as RAD23 or ATM, which may serve as key regulators for DNA damage processing via specific pathways. These data indicate that the organism might aim to protect the small number of valuable slow dividing stem cells by extensive DNA repair, whereas fast-proliferating progenitor cells, once damaged, are rather eliminated by apoptosis.
Newborn Screening for Developmental Disabilities: Reframing Presumptive Benefit
Authors: Bailey Donald B. , Skinner Debra , Warren Steven F.
Published: September 2005

A fundamental tenet of newborn screening is that screening should lead to a proven benefit for the infant. The standard is usually construed as medical benefit that significantly improves a child’s health. Screening for many conditions that cause developmental disabilities does not currently meet this standard.

We argue for expanding concepts of presumptive benefit. Newborn screening provides access to early intervention programs that are shown to positively influence child development and support families. Consumers want information about their children’s health and their own reproductive risk, and they have a broader view than policymakers of what constitutes a treatable disorder. Newborn screening provides other societal benefits that, in the absence of data showing harm and with appropriate attention to ethical and legal issues, warrant consideration of an expansion of targets for newborn screening.
Disability and Preventive Cancer Screening: Results from the 2001 California Health Interview Survey
Authors: Ramirez Anthony , Farmer Gail C. , Grant David , Papachristou Theodora
Published: September 2005

Objective. We sought to evaluate preventive cancer screening compliance among adults with disability in California.

Methods. We used data from the 2001 California Health Interview Survey to compare disabled and nondisabled adults for differences in preventive cancer screening behaviors. Compliance rates for cancer screening tests (mammography, Papanicolaou test, prostate-specific antigen, sigmoidoscopy/colonoscopy, and fecal occult blood test) between the 2 subpopulations were evaluated.

Results. Women with disabilities were 17% (Papanicolaou tests) and 13% (mammograms) more likely than women without disabilities to report noncompliance with cancer screening guidelines. Interactions between disability and reports of a doctor recommendation on cervical cancer screening were significant; women with disabilities had a lower likelihood of receiving a recommendation. Men with disabilities were 19% less likely than men without disabilities to report a prostate-specific antigen test within the last 3 years.

Conclusions.secondary to structural and/or clinical factors underpinning the differences found.
Growth Responses of Pinus radiata and Soil Changes following Periodic Fertilization
Authors: Ringrose C. , Neilsen W. A.
Published: September 2005

Low growth rates of Pinus radiata D. Don plantations on soils of low nutrient status in Tasmania require the development of nutrient management systems involving fertilization throughout the life of the stand. Periodic fertilization through 15 yr, in a Pinus radiata D. Don plantation in northeastern Tasmania was evaluated for effects on stand growth and soil. Substantial stem volume increases due to N and P fertilizer, applied as ammonium sulfate and single superphosphate were observed. Two applications of P fertilizer totaling 144 kg P ha−1 produced substantial increases in stem volume growth from 67 to 192 m3 ha−1 With P plus 13 annual applications of N fertilizer at 100 kg N ha−1 yr−1, stem volume growth increased from 192 to 344 m3 ha−1 over the 15‐yr period. Although fertilizing every second and fourth year produced less response, these treatments had better fertilizer‐use efficiency. Long‐term fertilization resulted in increases in concentrations of nutrients in the forest floor and the surface soil. The highest rates of fertilization were accompanied by significant reductions in soil pH throughout the soil profile, from 4.1 to 3.4 units. Reduction in pH occurred with both nitrogenous and phosphatic fertilizers. Substantial reductions in exchangeable Mg concentrations, from 235 to 88 μg g−1, were also measured throughout the soil profile. The highest rate of N application significantly increased the total O2 horizon biomass, with N mass doubling within the O2 horizon.
Improved Interpretation of Water Content Reflectometer Measurements in Soils
Authors: Kelleners T. J. , Seyfried M. S. , Blonquist J. M. , Bilskie J. , Chandler D. G.
Published: September 2005

Water content reflectometers use time domain reflectometry (TDR) to estimate the apparent permittivity of soil, which in turn can be related to the soil water content. The objective of this study is to develop a physical model for water content reflectometers. The length of the sensor rods and the delay time of the circuitry in the probe head are the two unknown parameters. The two parameters are determined both analytically, using sensor readings in air and deionized water, and by optimization, using air and non‐conductive fluids. The calibrated parameters are used to calculate the apparent permittivity as a function of water content for sensor readings in five soils, ranging from sand to silt loam. Calculated permittivity values are compared with Topp's permittivity‐water content relationship. Results show that the calculated permittivity values for the sand compare reasonably well with Topp's equation. The permittivity in the sandy loam to silt loam soils is overestimated by as much as 104 dimensionless permittivity units. The overestimated permittivity values are due to dielectric dispersion and ionic conductivity, brought about by the low effective frequency in the electromagnetic pulse of the sensors as compared with standard TDR. The performance of the reflectometers may be improved by increasing the frequency of operation of the sensors from <175 MHz to >1 GHz. At higher frequencies, the sensors become less sensitive to ionic conductivity. Furthermore, dielectric dispersion becomes less of an issue at higher frequencies, thereby increasing the applicability of existing permitivity‐water content relationships such as Topp's equation.
IKONOS Imagery to Estimate Surface Soil Property Variability in Two Alabama Physiographies
Authors: Sullivan Dana G. , Shaw J. N. , Rickman D.
Published: September 2005

Knowledge of surface soil properties is used to assess past erosion and predict erodibility, determine nutrient requirements, and assess surface texture for soil survey applications. This study was designed to evaluate high resolution IKONOS multispectral data as a soil‐mapping tool. Imagery was acquired over conventionally tilled fields in the Coastal Plain and Tennessee Valley physiographic regions of Alabama. Acquisitions were designed to assess the impact of surface crusting, roughness, and tillage on our ability to depict soil property variability. Soils consisted mostly of fine‐loamy, kaolinitic, thermic Plinthic Kandiudults at the Coastal Plain site and fine, kaolinitic, thermic Rhodic Paleudults at the Tennessee Valley site. Soils were sampled in 0.20‐ha grids to a depth of 15 cm and analyzed for percentages of sand (0.05–2 mm), silt (0.002–0.05 mm), clay (<0.002 mm), citrate‐dithionite extractable Fe, and total C (TC). Four methods of evaluating variability in soil attributes were evaluated: (i) kriging of soil attributes, (ii) cokriging with soil attributes and reflectance data, (iii) multivariate regression based on the relationship between reflectance and soil properties, and (iv) fuzzy c‐means clustering of reflectance data. Results indicate that cokriging with remotely sensed (RS) data improved field scale estimates of surface TC and clay content compared with kriging and regression methods. Fuzzy c‐means worked best using remotely sensed data acquired over freshly tilled fields, reducing soil property variability within soil zones compared with field scale soil property variability.
Bayesian parameter estimation with informative priors for nonlinear systems
Authors: Coleman Matthew C. , Block David E.
Published: September 2005

The estimation of parameters for nonlinear process models is often accomplished through optimization routines that search for a global optimum with respect to a least squares or weighted least squares criterion. While such an approach is often reasonable, it fails to account for all of the information that is available from the data and practitioner. Here we focus on the inclusion of prior knowledge in the estimation of parameters in nonlinear dynamic systems. We use the Bayesian paradigm to define the probability distribution over process model parameters, called the Bayesian posterior. The quantities associated with this posterior distribution (e.g., credible regions, means, modes) are estimated via Markov Chain Monte Carlo (MCMC) integration. We first give a short introduction to Bayesian parameter estimation and the role of MCMC in evaluating arbitrary probability distributions. Bayesian parameter estimation (via MCMC) is then applied to three case studies. The first case study shows the basic methodology of assigning and evaluating a Bayesian posterior to a simple problem that consists of estimating the mean and variance of a sample. The second case study uses prior information that specifies a preference for a particular type of reaction mechanism over another for a simulated fermentation system; the inclusion of such prior information is shown to improve the estimated values of the model parameters in situations where data are sparse or noisy (compared to the more common weighted least squares approach). The third case study develops a hybrid semi‐parametric neural network (NN) model to predict time‐dependent observed state variables (cell and protein concentration) in Escherichia coli fermentations. An integral step in the development of this hybrid model is parameter estimation of a nonlinear dynamic model. A hybrid model developed from the Bayesian parameter estimates is shown to outperform a hybrid model developed from the weighted least squares parameter estimates for predicting the final protein yield of a test set. © 2005 American Institute of Chemical Engineers AIChE J, 2006
Value of accuracy in linear systems
Authors: Bagajewicz Miguel
Published: September 2005

A connection between precision and downside expected lost revenue for linear systems was developed in previous work. Having the value of precision and accuracy in economic terms helps justify the upgrade of instrumentation and/or the increase in corrective maintenance repair rate. The connection between accuracy and economic value is extended in this article to the case where biases are present and in the context of existing corrective maintenance capabilities. © 2005 American Institute of Chemical Engineers AIChE J, 2006
Titelbild: CuH in a Bottle: A Convenient Reagent for Asymmetric Hydrosilylations (Angew. Chem. 39/2005)
Authors: Lipshutz Bruce H. , Frieman Bryan A.
Published: September 2005

Stabilität ist das Hauptmerkmal des außergewöhnlich reaktiven und enantioselektiven Reagens [{(R)‐(−)‐DTBM‐segphos}CuH], das B. H. Lipshutz und B. A. Frieman in ihrer Zuschrift auf S. 6503 ff. vorstellen (die Struktur ist im Titelbild gezeigt). Bisher war es bei ligandenkatalysierten Hydrosilylierungen notwendig, den Katalysator wegen seiner begrenzten Haltbarkeit vor jedem Einsatz eigens herzustellen. Dieses neue Reagens ist nun das erste asymmetrische “CuH aus der Flasche”.
Cover Picture: CuH in a Bottle: A Convenient Reagent for Asymmetric Hydrosilylations (Angew. Chem. Int. Ed. 39/2005)
Authors: Lipshutz Bruce H. , Frieman Bryan A.
Published: September 2005

The innate stability of the extraordinarily reactive and enantioselective reagent [{(R)‐(−)‐DTBM‐segphos}CuH] (whose structure is shown in the cover picture) is revealed in the Communication by Lipshutz and Frieman on page 6345 ff. Although there have been many advances in ligand‐accelerated catalysis of hydrosilylations, these reactions invariably require the preparation of the catalyst prior to use owing to their limited shelf‐life. This new reagent represents the first asymmetric “CuH in a Bottle”.
Correlation of rheumatoid arthritis severity with the genetic functional variants and circulating levels of macrophage migration inhibitory factor
Authors: Radstake Timothy R. D. J. , Sweep Fred C. G. J. , Welsing Paco , Franke Barbara , Vermeulen Sita H. H. M. , Geurts‐Moespot Anneke , Calandra Thierry , Donn Rachelle , van Riel Piet L. C. M.
Published: September 2005

Objective

To study whether genetic variants of macrophage migration inhibitory factor (MIF), the MIF −173G>C and CATT5–8 alleles, are associated with disease severity and levels of circulating MIF in patients with rheumatoid arthritis (RA).

Methods

Genotyping was performed in patients with early RA and in healthy controls. Demographic data, disease activity, and outcome measurements were compared between patients with and without the MIF variants. MIF −173G>C and CATT5–8 polymorphisms were genotyped, and a newly developed enzyme‐linked immunosorbent assay for human MIF was used. Allele and genotype distributions of the MIF −173G>C and CATT5–8 polymorphisms were compared between patients and controls by chi‐square test. Multiple regression analysis was performed to assess the independence of the MIF functional genetic variants as risk factors for radiologic joint damage.

Results

Genotyping of the −173G>C and CATT5–8 polymorphisms of MIF in RA patients and healthy individuals (n = 277 each) revealed similar frequencies of genotypes and haplotypes in both groups. No significant differences in demographic or clinical features were observed between RA patients carrying the MIF −173C allele or the MIF CATT7 allele or both and noncarrier RA patients. Radiologic joint damage was significantly higher in patients carrying risk alleles of the MIF −173G>C or the MIF CATT5–8 functional variants. No synergistic effects between both genetic variants were observed. Multivariate regression analysis revealed that presence of the MIF −173C/C and MIF CATT7/7 genotypes and having 1 MIF −173C allele were independent prognostic variables. Carriership of the MIF −173C allele (P = 0.002) or MIF CATT7 allele (P = 0.004) was associated with significantly higher circulating MIF levels compared with those in subjects having none of the risk‐conferring alleles, and greater circulating MIF levels correlated with more severe radiologic joint damage (r = 0.64, P = 0.001).

Conclusion

The MIF polymorphisms are not associated with RA susceptibility but are associated with high levels of radiologic joint damage. High circulating MIF levels were shown to correlate strongly with radiologic joint damage, suggesting that MIF expression is genetically determined and can be used as a novel prognostic tool in RA.
The relationship between cartilage loss on magnetic resonance imaging and radiographic progression in men and women with knee osteoarthritis
Authors: Amin Shreyasee , LaValley Michael P. , Guermazi Ali , Grigoryan Mikayel , Hunter David J. , Clancy Margaret , Niu Jingbo , Gale Daniel R. , Felson David T.
Published: September 2005

Objective

To determine the relationship between radiographic progression of joint space narrowing and cartilage loss on magnetic resonance imaging (MRI) in patients with symptomatic knee osteoarthritis (OA), and to investigate the location of MRI‐based cartilage loss in the knee and its relation to radiographic progression.

Methods

Two hundred twenty‐four men and women (mean age 66 years) were studied. Radiographs and MRI of the more symptomatic knee were obtained at baseline and at 15‐ and 30‐month followup. Radiographs of the knee (with weight‐bearing) were read for joint space narrowing (scale 0–3), with progression defined as any worsening in score. We used a semiquantitative method to score cartilage morphology in all 5 regions of the tibiofemoral joint, and defined cartilage loss as an increase in score (scale 0–4) at any region. We examined the relationship between progression of joint space narrowing on radiographic images and cartilage loss on MRI, using a generalized estimating equation proportional odds logistic regression, adjusted for baseline cartilage score, age, body mass index, and sex. The medial and lateral compartments were analyzed separately.

Results

In the medial compartment, 104 knees (46%) had cartilage loss detected by MRI. The adjusted odds ratio was 3.7 (95% confidence interval 2.2–6.3) for radiographic progression being predictive of cartilage loss on MRI. However, there was still a substantial proportion of knees (80 of 189 [42%]) with cartilage loss visible on MRI when no radiographic progression was apparent. Cartilage loss occurred frequently in the central regions of the femur and tibia as well as the posterior femur region, but radiographic progression was less likely to be observed when posterior femur regions showed cartilage loss. Radiographic progression appeared specific (91%) but not sensitive (23%) for cartilage loss. Overall findings were similar for the lateral compartment.

Conclusion

While our results provide longitudinal evidence that radiographic progression of joint space narrowing is predictive of cartilage loss assessed on MRI, radiography is not a sensitive measure, and if used alone, will miss a substantial proportion of knees with cartilage loss.
Racial/ethnic differences in surgical outcomes in veterans following knee or hip arthroplasty
Authors: Ibrahim Said A. , Stone Roslyn A. , Han Xiaoyan , Cohen Peter , Fine Michael J. , Henderson William G. , Khuri Shukri F. , Kwoh C. Kent
Published: September 2005

Objective

The utilization of joint arthroplasty for knee or hip osteoarthritis varies markedly by patient race/ethnicity. Because of concerns about surgical risk, black patients are less willing to consider this treatment. There are few published race/ethnicity‐specific data on joint arthroplasty outcomes. The present study was undertaken to examine racial/ethnic differences in mortality and morbidity following elective knee or hip arthroplasty.

Methods

Using information from the Veterans Administration National Surgical Quality Improvement Program database, data on 12,108 patients who underwent knee arthroplasty and 6,703 patients who underwent hip arthroplasty over a 5‐year period were analyzed. Racial/ethnic differences were determined using prospectively collected data on patient characteristics, procedures, and short‐term outcomes. The main outcome measures were risk‐adjusted 30‐day mortality and complication rates.

Results

Adjusted rates of both non–infection‐related and infection‐related complications after knee arthroplasty were higher among black patients compared with white patients (relative risk [RR] 1.50, 95% confidence interval [95% CI] 1.08–2.10 and RR 1.42, 95% CI 1.06–1.90, respectively). Hispanic patients had a significantly higher risk of infection‐related complications after knee arthroplasty (RR 1.64, 95% CI 1.08–2.49) relative to otherwise similar white patients. Race/ethnicity was not significantly associated with the risk of non–infection‐related complications (RR 0.97, 95% CI 0.68–1.38 in blacks; RR 1.18, 95% CI 0.60–2.30 in Hispanics) or infection‐related complications (RR 1.27, 95% CI 0.91–1.78 in blacks; RR 1.22, 95% CI 0.63–2.36 in Hispanics) after hip arthroplasty. The overall 30‐day mortality was 0.6% following knee arthroplasty and 0.7% following hip arthroplasty, with no significant differences by race/ethnicity observed for either procedure.

Conclusion

Although absolute risks of complication are low, our findings indicate that, after adjustment, black patients have significantly higher rates of infection‐related and non–infection‐related complications following knee arthroplasty, compared with white patients. In addition, adjusted rates of infection‐related complications after knee arthroplasty are higher in Hispanic patients than in white patients. Such differences between ethnic groups are not seen following hip arthroplasty. These groups do not appear to differ significantly in terms of post‐arthroplasty mortality rates.
Adalimumab for the treatment of patients with moderately to severely active psoriatic arthritis: Results of a double‐blind, randomized, placebo‐controlled trial
Authors: Mease Philip J. , Gladman Dafna D. , Ritchlin Christopher T. , Ruderman Eric M. , Steinfeld Serge D. , Choy Ernest H.S. , Sharp John T. , Ory Peter A. , Perdok Renee J. , Weinberg Mark A.
Published: September 2005

Objective

Adalimumab, a fully human, anti–tumor necrosis factor monoclonal antibody, was evaluated for its safety and efficacy compared with placebo in the treatment of active psoriatic arthritis (PsA).

Methods

Patients with moderately to severely active PsA and a history of inadequate response to nonsteroidal antiinflammatory drugs were randomized to receive 40 mg adalimumab or placebo subcutaneously every other week for 24 weeks. Study visits were at baseline, weeks 2 and 4, and every 4 weeks thereafter. The primary efficacy end points were the American College of Rheumatology 20% improvement (ACR20) response at week 12 and the change in the modified total Sharp score of structural damage at week 24. Secondary end points were measures of joint disease, disability, and quality of life in all patients, as well as the severity of skin disease in those patients with psoriasis involving at least 3% of body surface area.

Results

At week 12, 58% of the adalimumab‐treated patients (87 of 151) achieved an ACR20 response, compared with 14% of the placebo‐treated patients (23 of 162) (P < 0.001). At week 24, similar ACR20 response rates were maintained and the mean change in the modified total Sharp score was −0.2 in patients receiving adalimumab and 1.0 in those receiving placebo (P < 0.001). Among the 69 adalimumab‐treated patients evaluated with the Psoriasis Area and Severity Index (PASI), 59% achieved a 75% PASI improvement response at 24 weeks, compared with 1% of the 69 placebo‐treated patients evaluated (P < 0.001). Disability and quality of life measures were also significantly improved with adalimumab treatment compared with placebo. Adalimumab was generally safe and well‐tolerated.

Conclusion

Adalimumab significantly improved joint and skin manifestations, inhibited structural changes on radiographs, lessened disability due to joint damage, and improved quality of life in patients with moderately to severely active PsA.
Deficiency of type I interferon contributes to Sle2‐associated component lupus phenotypes
Authors: Li Jianwei , Liu Yang , Xie Chun , Zhu Jiankun , Kreska Desi , Morel Laurence , Mohan Chandra
Published: September 2005

Objective

Studies in mice and humans have implicated type I interferon (IFN‐I) in the pathogenesis of lupus. Given that the locus for IFN‐I is positioned within the Sle2 murine lupus susceptibility interval on chromosome 4, we undertook this study to investigate whether differences in IFN‐I levels might potentially contribute to the phenotypes ascribed to this locus.

Methods

IFN‐I, anti–IFN‐I, isotype control antibody, or phosphate buffered saline was administered to C57BL/6 and B6.Sle2 mice, and the serologic and cellular phenotypes were studied. In addition, B6.Sle2 mice were examined for structural and expression polymorphisms in the IFN‐I gene.

Results

In both B6.Sle2 congenic mice and C57BL/6 control mice, antibody‐mediated blockade of IFN‐I augmented serum autoantibody levels and boosted B1a cell numbers. Administration of IFN‐I ameliorated these 2 features previously attributed to this disease locus. Importantly, compared with B6 controls, B6.Sle2 mice had reduced levels of IFN‐I in their sera and cell culture supernatants, following stimulation. Although several sequence polymorphisms were noted in the Sle2 alleles of various IFN‐I genes, it was not established whether any of the noted sequence variations were causally related to the observed phenotypes.

Conclusion

Unexpectedly, reduction of IFN‐I levels reproduced the serologic and cellular phenotypes previously associated with the Sle2 lupus susceptibility interval. Placing these findings in the context of other studies, the effect of IFN‐I on systemic autoimmunity appears to be far more complex than originally perceived.
Analysis of the kinetics of osteoclastogenesis in arthritic rats
Authors: Schett Georg , Stolina Marina , Bolon Brad , Middleton Scot , Adlam Matt , Brown Heather , Zhu Li , Feige Ulrich , Zack Debra J.
Published: September 2005

Objective

To analyze the kinetics of osteoclastogenesis in 2 models of chronic immune‐mediated arthritis and 1 model of acute arthritis.

Methods

Adjuvant‐induced arthritis (AIA) and collagen‐induced arthritis (CIA) in Lewis rats were used as models of chronic arthritis. Acute arthritis was induced in Lewis rats by injecting carrageenan into the hind paw. Osteoclasts were identified by cathepsin K immunohistochemistry at various time points after the onset of arthritis. The location, size, and nucleation of osteoclasts were also analyzed.

Results

In both AIA and CIA, multinucleated and cathepsin K–positive osteoclasts first were observed on the day of disease onset. Initially, osteoclasts were localized at the periosteum next to the synovial membrane and in subchondral bone channels. The number, size, and nucleation of osteoclasts rapidly increased, leading to severe bone loss within days after disease onset. In addition, numerous mononucleated cathepsin K–positive osteoclast precursor cells emerged in the synovial membrane. All osteoclasts (cathepsin K–positive, multinucleated, attached to bone) and osteoclast precursors (cathepsin K–positive, mononucleated or multinucleated, within synovial tissue) were also positive for a macrophage‐specific marker. Upon induction of acute arthritis with carrageenan, osteoclasts formed transiently in subchondral bone, but regressed 7 days after disease onset.

Conclusion

Functional osteoclasts are generated at the earliest stage of arthritis, and new precursors are continuously formed in the synovial membrane to replenish the osteoclast pool. These data indicate that antiresorptive therapies may provide the most effective bone protection, when treatment is started soon after the onset of arthritis.
Tonic activation of hypoxia‐inducible factor 1α in avascular articular cartilage and implications for metabolic homeostasis
Authors: Brucker Peter U. , Izzo Nicholas J. , Chu Constance R.
Published: September 2005

Objective

To determine whether oxygen‐dependent activation patterns of hypoxia‐inducible factor 1α (HIF‐1α) observed in vascularized tissues are conserved within avascular and hypoxic articular cartilage and whether HIF‐1α affects cartilage matrix synthesis.

Methods

Explants of bovine articular cartilage and primary chondrocytes were exposed to normoxia (21% O2), hypoxia (2% O2), and simulated hypoxia (21% O2 plus CoCl2). Western blot and immunofluorescence analyses of HIF‐1α were performed to determine HIF‐1α activation patterns. To simulate cartilage loss from disease or injury, the top layers of cartilage were removed from osteochondral explants, and the residual cartilage was assessed for HIF‐1α immunolocalization and proteoglycan synthesis.

Results

We demonstrated continuous nuclear translocation of HIF‐1α in deeper layers of intact articular cartilage. HIF‐1α was not completely degraded in chondrocytes exposed to normoxia, but rather, colocalized to the Golgi complex, a finding not previously reported for any cell type. Following alteration of the oxygen gradient by removal of the top layers of cartilage, predominantly perinuclear HIF‐1α was found in the deeper layers. Restoration of intranuclear HIF‐1α to these areas was achieved by hypoxia and simulated hypoxia. Under conditions in which HIF‐1α was inactivated, matrix synthetic activity was altered (P < 0.0001) compared with control cartilage.

Conclusion

These findings demonstrate that hypoxia‐dependent activation of HIF‐1α is highly conserved and that changes in oxygen tensions following cartilage loss from injury or disease alter cartilage metabolism in part by changing HIF‐1α activity. The discovery of tonic activation of HIF‐1α within intact articular cartilage underscores its potential importance to cartilage homeostasis.
How much of the increased incidence of heart failure in rheumatoid arthritis is attributable to traditional cardiovascular risk factors and ischemic heart disease?
Authors: Crowson Cynthia S. , Nicola Paulo J. , Kremers Hilal Maradit , O'Fallon W. Michael , Therneau Terry M. , Jacobsen Steven J. , Roger Veronique L. , Ballman Karla V. , Gabriel Sherine E.
Published: September 2005

Objective

To compare the proportion of the risk for the development of heart failure (HF) that is attributable to traditional cardiovascular (CV) risk factors, ischemic heart disease (IHD), and alcohol abuse between subjects with and subjects without rheumatoid arthritis (RA).

Methods

A population‐based inception cohort of RA patients was assembled along with a similar cohort of subjects without RA. All individuals were followed up through their complete medical records, until HF incidence, death, migration, or January 1, 2001. The attributable risk of HF was estimated as the difference between the observed cumulative incidence of HF in each cohort (estimated from multivariable Cox models and adjusted for the competing risk of death) and the predicted cumulative incidence of HF in the absence of risk factors, with results expressed as a percentage of the observed cumulative incidence.

Results

A total of 575 RA subjects and 583 non‐RA subjects (mean age 57 years, 73% women) without HF at incidence/index date had a mean followup of 15.1 and 17.0 years, respectively. During that period, 165 RA and 115 non‐RA subjects had a first episode of HF, with a cumulative incidence of 36.3% and 20.4%, respectively, at age 80 years. Among non‐RA subjects, 77% of the HF at age 80 years was attributable to CV risk factors, IHD, and alcohol abuse combined, whereas among RA subjects, only 54% of the HF at age 80 years was attributable to these factors (P < 0.01).

Conclusion

The excess risk of HF among RA patients is not explained by an increased frequency or effect of CV risk factors and IHD.
Genome‐wide analysis of the transcriptional response of murine hybridomas to osmotic shock
Authors: Shen Duan , Sharfstein Susan T.
Published: September 2005

Hyperosmotic stress has been shown to increase specific antibody productivity in murine hybridoma systems; however, the mechanisms underlying this phenomenon are still poorly understood. To elucidate the mechanisms for this phenomenon as well as other physiological changes that occur in response to hyperosmotic stress, we performed a genome‐wide analysis of the transcriptional response of murine hybridoma OKT3 toward hyperosmotic stress using DNA microarrays. GeneChip® MOE430A from Affymetrix was used to determine the differences in transcription patterns between OKT3 in hyperosmotic culture (∼100 mOsm above control) and control culture. The chip contains 22,690 probe sets for over 14,000 known genes and more than 4,000 ESTs. Signals were normalized using the GC‐RMA algorithm and the effectiveness of hyperosmotic stress in altering the expression of each gene was evaluated using one‐way ANOVA. 2,793 probe sets on the chip were differentially expressed with a P < 0.05. Among them, 349 probe sets exhibited a two‐fold or greater change (with 202 up‐regulated and 147 down‐regulated) at one or more time points. Within the 215 characterized, differentially expressed genes, many are involved in metabolism/catabolism (19 induced, 12 repressed), cell‐cycle regulation (10 induced, 5 repressed) and apoptosis (8 induced, 2 repressed), regulation of transcription (18 induced, 13 repressed) and translation (2 induced, 2 repressed), transport and signaling pathways (24 induced, 12 repressed). Surprisingly, there were very few changes within the stress‐response genes. Interestingly, the transcription levels of both the immunoglobulin kappa and lambda light chains showed a significant change in response to hyperosmotic stress, although there is no detectable lambda chain in the immunoglobulin produced in this cell line. Quantitative PCR assays with TaqMan® probes were applied to selected genes to validate the results obtained from microarray analysis. © 2005 Wiley Periodicals, Inc.
Functionalized Nanodiamonds Part I. An Experimental Assessment of Diamantane and Computational Predictions for Higher Diamondoids
Authors: Fokin Andrey A. , Tkachenko Boryslav A. , Gunchenko Pavel A. , Gusev Dmitriy V. , Schreiner Peter R.
Published: September 2005

The structures, strain energies, and enthalpies of formation of diamantane 1, triamantane 2, isomeric tetramantanes 3–5, Td‐pentamantane 6, and D3d‐hexamantane 7, and the structures of their respective radicals, cations, as well as radical cations, were computed at the B3LYP/6‐31G* level of theory. For the most symmetrical hydrocarbons, the relative strain (per carbon atom) decreases from the lower to the higher diamondoids. The relative stabilities of isomeric diamondoidyl radicals vary only within small limits, while the stabilities of the diamondoidyl cations increase with cage size and depend strongly on the geometric position of the charge. Positive charge located close to the geometrical center of the molecule is stabilized by 2–5 kcal mol−1. In contrast, diamondoid radical cations preferentially form highly delocalized structures with elongated peripheral CH bonds. The effective spin/charge delocalization lowers the ionization potentials of diamondoids significantly (down to 176.9 kcal mol−1 for 7). The reactivity of 1 was extensively studied experimentally. Whereas reactions with carbon‐centered radicals (Hal)3C. (Hal=halogen) lead to mixtures of all possible tertiary and secondary halodiamantanes, uncharged electrophiles (dimethyldioxirane, m‐chloroperbenzoic acid, and CrO2Cl2) give much higher tertiary versus secondary selectivities. Medial bridgehead substitution dominates in the reactions with strong electrophiles (Br2, 100 % HNO3), whereas with strong single‐electron transfer (SET) acceptors (photoexcited 1,2,4,5‐tetracyanobenzene) apical C4H bridgehead substitution is preferred. For diamondoids that form well‐defined radical cations (such as 1 and 4–7), exceptionally high selectivities are expected upon oxidation with outer‐sphere SET reagents.
Simulation of 59Co NMR Chemical Shifts in Aqueous Solution
Authors: Bühl Michael , Grigoleit Sonja , Kabrede Hendrik , Mauschick Frank T.
Published: September 2005

59Co chemical shifts were computed at the GIAO‐B3LYP level for [Co(CN)6]3−, [Co(H2O)6]3+, [Co(NH3)6]3+, and [Co(CO)4]− in water. The aqueous solutions were modeled by Car–Parrinello molecular dynamics (CPMD) simulations, or by propagation on a hybrid quantum‐mechanical/molecular‐mechanical Born–Oppenheimer surface (QM/MM‐BOMD). Mean absolute deviations from experiment obtained with these methods are on the order of 400 and 600 ppm, respectively, over a total δ(59Co) range of about 18 000 ppm. The effect of the solvent on δ(59Co) is mostly indirect, resulting primarily from substantial metal–ligand bond contractions on going from the gas phase to the bulk. The simulated solvent effects on geometries and δ(59Co) values are well reproduced by using a polarizable continuum model (PCM), based on optimization and perturbational evaluation of quantum‐mechanical zero‐point corrections.
“Heavy Fluorous” Cyclopentadienes and Cyclopentadienyl Complexes with Three to Five Ponytails: Facile Syntheses from Polybromocyclopentadienyl Complexes, Phase Properties, and Electronic Effects
Authors: Dinh Long V. , Gladysz John A.
Published: September 2005

The reactions between [(η5‐C5H5−xBrx)M(CO)3] (M=Re, Mn; x=1, 3, 4, 5) and [IZn{(CH2)nRf8}] (n=2, 3; Rf8=(CF2)7CF3) in the presence of [Cl2PdL2] catalysts give the title complexes [{η5‐C5H5−x[(CH2)nRf8]x}M(CO)3]. In the case of x=5, the major product is actually [{η5‐C5H[(CH2)nRf8]4}M(CO)3], in which one of the bromides has been substituted by hydride. Minor amounts of multiple hydride substitution products are formed, all of them readily separable on fluorous silica gel. Irradiation of the manganese complexes in CF3C6H5/MeOH/ether gives uncoordinated cyclopentadienes, which can be deprotonated and reattached to other metals. Partition coefficients have been measured (CF3C6F11/toluene): complexes with three or more ponytails are highly fluorophilic, with values of >99.8:<0.2. The IR $\tilde \nu $CO bands have been used to probe the inductive effects of the ponytails at the metal centers.