bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of a Safe Range of Knee Flexion Angles for Fixation of the Grafts in Double-Bundle Anterior Cruciate Ligament Reconstruction
Authors: Vercillo Fabio , Woo Savio L-Y. , Noorani Sabrina Y. , Dede Özgür 
Published: April 2007

Background For anterior cruciate ligament reconstruction with a double-bundle procedure, one of the major concerns is to not predispose either one of the grafts to risk of failure by overloading. Hypothesis Knee flexion angles between 15° and 45° for anteromedial graft fixation and 15° for posterolateral graft fixation are safe for both grafts in double-bundle anterior cruciate ligament reconstruction. Study Design Controlled laboratory study. Methods Nine human cadaveric knees were tested. The double-bundle anterior cruciate ligament reconstruction was conducted with both grafts fixed at 15° of knee flexion (fixation protocol 15/15) and again with the anteromedial and posterolateral grafts fixed at 45° and 15° of knee flexion (fixation protocol 45/15). For both fixation protocols, the knee kinematics and the in situ forces of the reconstructed anterior cruciate ligament and its individual grafts were measured and collected under an anterior tibial load of 134 N and combined rotatory loads of 10 N·m of valgus and 5 N·m of internal tibial torque. The data from both fixation protocols were compared with those of an intact knee. Results In response to the 2 external loading conditions, both fixation protocols (15/15 and 45/15) could restore the knee kinematics to within 2 mm of the intact knee (although statistically significant differences were found between fixation protocol 15/15 and the intact knee) and the overall in situ forces in the grafts similar to the intact anterior cruciate ligament. In response to the 134-N anterior tibial load, the in situ forces in the anteromedial graft for both fixation protocols did not exceed those of the intact anteromedial bundle. But at 30° and 45° of knee flexion, the in situ forces for fixation protocol 15/15 were 20.7% and 22.1% lower, respectively, when compared with the intact anteromedial bundle. Under combined rotatory loads, the anteromedial graft for fixation protocol 15/15 had in situ forces that were 45% lower than the intact anteromedial bundle at 30° of knee flexion. The in situ force in the posterolateral graft for both fixation protocols did not exceed those of the intact posterolateral bundle, nor were they significantly different from the intact posterolateral bundle at any of the flexion angles tested. Conclusion Both fixation protocols restored knee kinematics without predisposing either graft to failure. Therefore, knee flexion angles between 15° and 45° for graft fixation were found to be safe for the anteromedial graft, while 15° of knee flexion was safe for the posterolateral graft. Clinical Relevance A range of knee flexion angles that is safe for the fixation of both grafts in double-bundle anterior cruciate ligament reconstruction was determined.
Patellofemoral Contact Pressures and Lateral Patellar Translation after Medial Patellofemoral Ligament Reconstruction
Authors: Beck Paul , Brown Nicholas A. T. , Greis Patrick E. , Burks Robert T. 
Published: April 2007

Background Overtensioning of medial patellofemoral ligament reconstructions may lead to adverse surgical outcomes. Hypothesis Increasing tension on a medial patellofemoral ligament graft will increase patellofemoral contact forces and decrease lateral patellar translation. Study Design Controlled laboratory study. Methods Patellofemoral contact pressures were measured in 8 fresh-frozen cadaveric knees before and after transection of the medial patellofemoral ligament and after a standardized reconstruction surgery. Contact pressures were measured at 3 knee angles (30°, 60°, and 90°) and under 3 levels of tension applied to the graft (2, 10, and 40 N). For each condition, patellar translation was measured at 30° of knee flexion as a 22-N lateral force was applied. Results Graft tension of 2 N restored normal translation, but 10 N and 40 N significantly restricted motion (5.2 mm and 1.9 mm, respectively). Compared with the intact knee, medial patellofemoral contact pressures significantly increased (P < .05) when 40 N of tension was applied to the reconstruction. Medial contact pressures were restored to normal with 2 N of graft tension. Lateral patellar translation was significantly greater (P < .05) after the medial patellofemoral ligament was cut (16.3 mm) compared with intact (7.7 mm). Conclusion Low (2-N) tension applied to a medial patellofemoral ligament reconstruction stabilized the patella and did not increase medial patellofemoral contact pressures. Higher loads (10 N and 40 N) progressively restricted lateral patellar translation and inappropriately redistributed patellofemoral contact pressures. Clinical Relevance Overtensioning can be avoided by applying low loads to medial patellofemoral ligament reconstructions, which reestablished normal translation and patellofemoral contact pressures.
Concomitant Meniscal Allograft Transplantation and Autologous Chondrocyte Implantation
Authors: Farr Jack , Rawal Ashish , Marberry Kevin M. 
Published: April 2007

Background Although recent studies have shown intermediate-term success of both meniscal allograft transplantation (MAT) and autologous chondrocyte implantation (ACI) performed separately, there have been no peer-reviewed studies focused prospectively on the combined procedure. By potentially reestablishing a compartment contact area closer to normal, MAT may allow a more optimal environment for ACI by reducing stress (stress = force/unit area). On the other hand, the literature suggests that MAT alone in the presence of extensive chondrosis performs poorly. Restoring the articular cartilage may allow the MAT to perform more similarly to series with nearly normal articular cartilage. Hypothesis Performed concomitantly, ACI and MAT will result in significant improvements in knee function as measured by functional scoring scales and visual analog pain scales. Study Design Case series; Level of evidence, 4. Methods Preoperative and postoperative comparisons of Browne modified Cincinnati functional levels, Lysholm, visual analog rest and maximum pain, and satisfaction scores were recorded. Thirty-six total procedures were performed between 1999 and 2004. Results Of the 36 patients entering the series, 29 had >2-year evaluation and scores. Four patients were recorded as failures before the 2-year follow-up and required revision surgery. Three patients were lost to follow-up. A total of 21 medial and 8 lateral MAT/femoral condyle ACIs were performed. Sixteen of 29 patients had concomitant procedures performed, including tibial tuberosity osteotomy, anterior cruciate ligament reconstruction, and high tibial osteotomy. Patients demonstrated statistically significant improvement in the standardized outcome surveys, visual analog pain, and satisfaction scores. The Browne Cincinnati (Patient and Clinician, respectively) showed an improvement from 3.9 (standard deviation [SD], 1.5) and 4.0 (SD, 1.4) preoperatively to 6.3 (SD, 1.9) postoperatively for both. The Lysholm also showed an improvement from 57.7 (SD, 16.2) preoperatively to 77.7 (SD, 19.3) postoperatively. There were no significant differences noted in any of the subgroups (medial vs lateral, isolated vs concomitant, or unipolar vs bipolar). Conclusion At a minimum of 2-year follow-up, MAT in combination with ACI demonstrates improvement in both symptoms and knee function. However, the improvements are less than literature-reported outcomes of either procedure performed in isolation.
Quantitation of hepcidin from human and mouse serum using liquid chromatography tandem mass spectrometry
Authors: Murphy Anthony T. , Witcher Derrick R. , Luan Peng , Wroblewski Victor J. 
Published: April 2007

Abstract
The hepatic peptide hormone hepcidin is considered the central regulator of iron metabolism. Characterizing the circulating levels of this peptide is critical to understanding its role in the development of clinically relevant syndromes, such as anemia of inflammation/chronic disease, and may provide insight into potential clinical interventions. While quantitative methods have been published for the determination of urinary hepcidin and serum prohepcidin, no definitive methods have been published for the determination of hepcidin in serum. In this report, we describe a quantitative method for the determination of both human and mouse hepcidin in serum and plasma. The method employs protein precipitation and solid-phase extraction followed by liquid chromatographic separation and tandem mass spectrometry detection. The method has a quantitative range of 0.25 ng/mL to 500 ng/mL serum for mouse hepcidin and 1 ng/mL to 500 ng/mL serum for human hepcidin. The method uses small sample volumes (50 μL for mice and 100 μL for humans) and 96-well formats for rapid sample processing. The method was used to establish baseline serum and plasma concentrations of hepcidin in normal C57Bl/6 mice and healthy human volunteers.
Functional analysis of fibrin γ-chain cross-linking by activated factor XIII: determination of a cross-linking pattern that maximizes clot stiffness
Authors: Standeven Kristina F. , Carter Angela M. , Grant Peter J. , Weisel John W. , Chernysh Irina , Masova Leona , Lord Susan T. , Ariëns Robert A. S. 
Published: April 2007

AbstractActivated coagulation factor XIII (FXIIIa) cross-links the γ-chains of fibrin early in clot formation. Cross-linking of the α-chains occurs more slowly, leading to high molecular weight multimer formations that can also contain γ-chains. To study the contribution of FXIIIa-induced γ-chain cross-linking on fibrin structure and function, we created 2 recombinant fibrinogens (γQ398N/Q399N/K406R and γK406R) that modify the γ-chain cross-linking process. In γK406R, γ-dimer cross-links were absent, but FXIIIa produced a cross-linking pattern similar to that observed in tissue transglutaminase cross-linked fibrin(ogen) with mainly α-γ cross-links. In Q398N/Q399N/K406R, cross-links with any γ-chain involvement were completely absent, and only α-chain cross-linking occurred. Upon cross-linking, recombinant normal fibrin yielded a 3.5-fold increase in stiffness, compared with a 2.5-fold increase by α-chain cross-linking alone (γQ398N/Q399N/K406R). γK406R fibrin showed a 1.5-fold increase in stiffness after cross-linking. No major differences in clot morphology, polymerization, and lysis rates were observed, although fiber diameter was slightly lower in cross-linked normal fibrin relative to the variants. Our results show that γ-chain cross-linking contributes significantly to clot stiffness, in particular through γ-dimer formation; α-γ hybrid cross-links had the smallest impact on clot stiffness.
SIV-specific CD8+ T cells express high levels of PD1 and cytokines but have impaired proliferative capacity in acute and chronic SIVmac251 infection
Authors: Petrovas Constantinos , Price David A. , Mattapallil Joseph , Ambrozak David R. , Geldmacher Christof , Cecchinato Valentina , Vaccari Monica , Tryniszewska Elzbieta , Gostick Emma , Roederer Mario , Douek Daniel C. , Morgan Sara H. , Davis Simon J. , Franchini Genoveffa , Koup Richard A. 
Published: April 2007

AbstractProgrammed death-1 (PD-1) is a critical mediator of virus-specific CD8+ T-cell exhaustion. Here, we examined the expression of PD-1 on simian immunodeficiency virus (SIV)-specific CD8+ T cells and its possible involvement in regulation of cytokine production, proliferation, and survival of these cells. The majority of SIV-specific CD8+ T cells expressed a PD-1high phenotype, independent of their differentiation status, in all tissues tested. PD-1 expression gradually declined on CD8+ T cells specific for SIV-derived epitopes that had undergone mutational escape, indicating that antigen-specific TCR stimulation is the primary determinant of PD-1 expression. SIV-specific PD-1highCD8+ T cells produced IFN-γ, TNF-α, and IL-2 under cognate peptide stimulation. While CD8+ T cells that proliferated in response to antigen had a PD-1high phenotype, it was determined that there was a reduced proliferative capacity of PD-1high compared with PD-1low SIV-specific CD8+ T cells. PD-1high SIV-specific CD8+ T cells were highly susceptible to cell death leading to loss of such cells after in vitro stimulation. Thus, PD-1 is a negative regulator of SIV-specific CD8+ T cells, operating predominantly through the induction of cell death. Manipulation of the interaction of PD-1 with its ligands could thus potentially restore the CD8+ T-cell responses in SIV infection.
Femoral Head Osteonecrosis in Pediatric and Young Adult Patients With Leukemia or Lymphoma
Authors: Karimova Evguenia J. , Rai Shesh N. , Howard Scott C. , Neel Michael , Britton Lunetha , Pui Ching-Hon , Kaste Sue C. 
Published: April 2007

Purpose Osteonecrosis of the capital femoral epiphysis is a significant late toxicity of treatment for childhood leukemia and lymphoma. We determined clinical and imaging risk factors predicting clinical joint outcomes of femoral head osteonecrosis in pediatric patients with leukemia or lymphoma. Patients and Methods We reviewed retrospectively medical records and magnetic resonance imaging scans of 80 patients with osteonecrosis of the capital femoral epiphysis. Logistic regression was used to examine relationships between risk factors and outcomes of joint surface collapse and arthroplasty. We used Kaplan-Meier survival curves to display the time to joint surface collapse and arthroplasty based on selected predictors. Results Median time between primary diagnosis and diagnosis of osteonecrosis of the hip was 1.7 years (range, 0.1 to 17.5 years). Twenty-three patients (29%) underwent arthroplasty in 36 hips at a mean of 1.3 years (range, 0.5 to 8.6 years) after diagnosis of osteonecrosis. Median age at time of first arthroplasty was 20.1 years (range, 15.1 to 35.4 years). Joint outcome of osteonecrosis was predicted solely by lesion size at diagnosis of osteonecrosis. The worst prognosis was associated with lesions occupying more than 30% of the femoral head volume; 80% of hips with these lesions collapsed within 2 years of diagnosis and 50% required arthroplasty. Conclusion Lesion size of osteonecrosis is the best predictor of clinical joint outcome of hip osteonecrosis in survivors of pediatric hematologic malignancy. Lesions occupying more than 30% of the femoral head have high likelihood of joint deterioration necessitating arthroplasty at a young age.
Adverse effects on growth rates in rats caused by buprenorphine administration
Authors: Jacobson C. 
Published: April 2007

As a routine postoperative treatment, a single dose of buprenorphine was given to rats at a dose of 0.05 mg/kg subcutaneously. However, some rats developed abnormal secretions around the nose and mouth and some animals died 3-5 days after surgery and analgesic treatment. At autopsy a yellow fibrous mass was found in the stomach and intestines. Observations of animals given buprenorphine revealed an abnormal ingestion of bedding material. This caused a disturbance to normal digestion, with gastric distension, weight loss or decreased growth rate, constipation and occasionally death. In this study rats were monitored for 6 days following surgery and analgesic treatment. A comparison of growth rates was made between rats given saline and buprenorphine or na1buphine and between animals kept on bedding or grid floors for the first 24 h after treatment. Of the animals held on bedding, the buprenorphine-treated animals did not lose weight as the other animals did, but had on the other hand a decreased growth rate during the measuring period of 6 days after surgery. When denied access to bedding for the first 24 h after surgery, rats given saline or na1buphine had a reduced weight gain over the first 24 h, similar to the groups held on bedding. Rats held on grid floors and given buprenorphine continued to gain weight for the first 24h. From day 3, there was no significant difference between the groups, which all gained weight.
Influence of situational and conceptual rewording on word problem solving
Authors: Vicente Santiago. , Orrantia Jose. , Verschaffel Lieven. 
Published: April 2007

Background. Studies on rewording word problems can be grouped into two main groups: situational rewording, in which the situation denoted by the text is described more richly, and conceptual rewording, in which the underlying semantic relations are highlighted.Aims. Our aims are to define and distinguish these two kinds of rewording and to test empirically their relative effectiveness in two different studies.Sample. In the first study, 79 third graders, 64 fourth graders and 65 fifth graders took part; the sample for Study 2 was similar.Method. In Study 1, children were asked to solve both easy and difficult two‐step change problems in three different versions: standard, situational and conceptual rewording. In Study 2, three different versions of the situational version were compared: one with only temporal elaborations, one with only causal elaborations and a ‘complete’ version combining both elaborations.Results. In Study 1, conceptually reworded problems elicited the best results, especially among younger children and for difficult two‐step problems. Neither in Study 1 nor in Study 2 did the situationally reworded problems yield better performance than standard items.Conclusion. Only conceptual rewording has proved to be useful for improving children's performance, especially among younger children and for difficult problems. The lack of impact of situational rewording cannot be explained in terms of the length of the resulting text.
Old Love: Johannes Brahms, Clara Schumann, and the Poetics of Musical Memory
Authors: BERRY PAUL 
Published: April 2007

ABSTRACT
In September 1871, Johannes Brahms presented Clara Schumann with an untitled work in F# minor for solo piano, which he later revised and published as the Capriccio, op. 76/1. Surviving correspondence demonstrates Clara's intimate familiarity with the work throughout the 1870s. In May 1876, two years before releasing manuscripts of the Capriccio among his wider circle, Brahms composed the song Alte Liebe (Old Love) to a poem by Carl Candidus; he immediately sent an autograph to the baritone Julius Stockhausen, along with instructions to sing it to Clara, whom he proclaimed the best person to hear it. Examination of the music against the backdrop of its origins and the circumstances of its initial performance reveals that Brahms deliberately incorporated echoes of the Capriccio into Alte Liebe and points to ways in which those echoes might have influenced Clara's understanding of the song and its text. A broad array of music-analytic and documentary evidence (including the newly rediscovered autograph of Alte Liebe) permits detailed investigation of the interpretive perspective that Brahms's compositional choices encouraged from a listener with Clara's unique musical memories and manner of interacting with chamber music. Imaginatively reconstructing her encounter with Alte Liebe yields fresh insights into Brahms's compositional practice in the private genres of song and small-scale chamber music, a rich new historical context in which to ground the study of allusion in his works, and a rare opportunity to explore the musical and personal dynamics of his closest friendship.
Ozone toxicity symptoms among flight attendants
Authors: Reed Dwayne , Glaser Sally , Kaldor John 
Published: April 2007

AbstractBecause of persistent complaints of ozone‐toxicity type symptoms among crew members of commercial airlines, we undertook a survey to determine the extent of the problem and the associated flight factors. Self‐reported questionnaires and flight diaries were completed by 1,330 flight attendants, (FAs) working for three different airlines. Ozone‐toxicity type symptoms were reported three or four times more frequently by FAs with airlines flying at high altitudes than by those with low‐flying airlines. When examined by characteristics of flights, the ozone‐toxicity type symptoms were significantly associated with flight altitude, duration and type of aircraft, but not with years worked, sex, medical history, or home residence. Other symptoms indicative of fatigue or stress were mainly associated with flight duration. While these indirect data cannot implicate ozone specifically, they offer evidence that ozone‐related health problems do exist among a large proportion of FAs.
Spirometric “abnormality” in a normal male reference population: Further analysis of the 1971 oregon survey
Authors: Miller Albert , Thornton John C. , Smith Harry , Morris James F. 
Published: April 2007

AbstractConventional criteria for spirometric impairment (FVC and FEV1 ⩽ 79% predicted, FEF25‐75 ⩽ 74% predicted, FEV1/FVC ⩽ 0.69 for most ages) were applied to 507 healthy nonsmoking male subjects in the 1971 Oregon survey. Frequency of air flow impairment was higher than expected for a normal population. Of all subjects, 17.8% had an “abnormal” FEF25‐75% and 19.7% an “abnormal” FEV1/FVC. “Decreased” lung volumes were seen in older subjects; of those over 55 years of age, 8.8% had a reduced FVC and 11.8% a reduced FEV1. These rates in a normal population may be used as a rough baseline for making inferences about a population under study. Similar rates were found in a cross‐sectional survey of nonsmoking males representative of the population of a large industrial state.The major reason for these high rates of “abnormal” spirometry lies in the conventional definitions of abnormality. Tables showing cut‐off points for abnormal spirometric values based on a 95% confidence interval for adult males of all ages and heights permit an alternative method for classification as abnormal.
Low‐level arsenic exposure in wood processing plants
Authors: Rosenberg Michael J. , Landrigan Philip J. , Crowley Stephen 
Published: April 2007

AbstractIn October 1978, seven construction workers building a pier in Monterey, California, developed symptoms consistent with arsenic intoxication and had elevated urinary levels of arsenic. The wood used for the pier had been pressure‐treated with an arsenic preservative. To evaluate the potential acute medical hazards of preserving wood with arsenic, we evaluated employees at three California plants where arsenic preservatives are mixed and applied to wood. Histories, physical examinations, and urine specimens for arsenic analysis were collected from 44 workers exposed to arsenic and from 37 controls in three woodworking plants where arsenic is not used. A comparison of the groups failed to show any significant differences in history or physical examination. Adjustment for age, length of employment, and smoking histories did not alter the pattern. Urinary arsenic concentration was found to increase with increased exposure. These results do not imply absence of chronic or delayed toxicity, nor do they preclude the presence of a more subtle toxicity such as nerve conduction deficits. The data indicate existence of an arsenic exposure hazard in wood processing.