bluuebunny/crossref_metadata_2025_split huggingface dataset:
Monopolar Radiofrequency Treatment of Partial-Thickness Cartilage Defects in the Sheep Knee Joint Leads to Extended Cartilage Injury
Authors: Kääb Max J. , Bail Herman J. , Rotter Andreas , Mainil-Varlet Pierre , apGwynn Iolo , Weiler Andreas 
Published: July 2005

Background The application of radiofrequency energy to smooth and stabilize the cartilage surface has become increasingly controversial. There is little knowledge on extended-term effects, such as cartilage viability. Purpose To analyze the effect of radiofrequency treatment on artificially created partial-thickness defects in the femoral cartilage of sheep knee joints 24 weeks after surgery. Study Design Controlled laboratory study. Methods Grade II cartilage surface defects on the medial and lateral femoral condyles were artificially created in sheep for in vivo analysis. The cartilage lesions were treated alternately on the lateral or the medial condyle using a monopolar radiofrequency probe. Radiofrequency treatment was performed in a freehand technique until surface smoothing without change of cartilage color was seen. At 24 weeks after surgery, cartilage samples were harvested and were processed for macroscopic and histological evaluation. To analyze the effect of radiofrequency at time zero, samples of sheep femoral condyle cartilage with and without artificially created clefts were treated in vitro with radiofrequency. Evaluation was performed by scanning electron and confocal microscopy. Results At 24 weeks after surgery, grade IV cartilage defects were detected in all radiofrequency-treated samples. The histological findings showed a central ulcer and dead chondrocytes in the radiofrequency-treated regions. The radiofrequency-treated cartilage revealed partial surface irregularities with partial-defect repair. After radiofrequency treatment in vitro, samples at time zero showed smoothing of the artificially created clefts, as seen by scanning electron microscopy. Confocal microscopy showed necrosis of chondrocytes over approximately one fourth of the upper cartilage thickness. Conclusion Even if chondrocyte death is seen only in approximately one fourth of the upper cartilage layers in the sheep femur after in vitro application, radiofrequency treatment can cause damage to cartilage 24 weeks after application. Clinical Relevance Caution is recommended in the application of monopolar radiofrequency energy by visual control to partialthickness cartilage defects. Irregular fronds of chondromalacia may be unattractive but represent viable articular cartilage. Using radiofrequency to obtain a more visually pleasing smooth surface may be counterproductive.
Effect of Patellar Tendon Shortening on Tracking of the Patella
Authors: Upadhyay Neil , Vollans Samuel R. , Seedhom Bahaa B. , Soames Roger W. 
Published: July 2005

Background Although 10% postoperative patellar tendon shortening after bone–patellar tendon–bone autograft reconstruction of the anterior cruciate ligament has been reported, there are no published studies assessing the effect of shortening on patellofemoral joint biomechanics under physiological loading conditions. Purpose To investigate the influence of patellar tendon shortening on patellofemoral joint biomechanics. Study Design Controlled laboratory study. Methods The authors evaluated the patellofemoral contact area, the location of contact, and the patellofemoral joint reaction force and contact stresses in 7 cadaveric knees before and after 10% patellar tendon shortening. Shortening was achieved using a specially designed device. Experimental conditions simulating those occurring during level walking were employed: physiological quadriceps loads and corresponding angles of tibial rotation were applied at 15 °, 30 °, and 60 ° flexion of the knee. Patellofemoral joint contact areas were measured before and after shortening using the silicone oil–carbon black powder suspension squeeze technique. Results After patellar tendon shortening, patellofemoral joint contact areas were displaced proximally on the patellar surface and distally on the femoral surface. Although the contact area increased by 18% at 15 ° of knee flexion (P=. 04), no significant change occurred at 30 ° or 60 ° of knee flexion (P>. 05). Patellofemoral contact stress remained unchanged after patellar tendon shortening (P>. 05) at each flexion angle. Conclusion Our results suggest that a 10% shortening of the patellar tendon does not alter patellar contact stresses during locomotion. It is not clear whether apparent changes in contact location in all positions and contact area at 15 ° would have clinical consequences.
Open Bankart Repair
Authors: Sachs Raymond A. , Williams Bradley , Stone Mary Lou , Paxton Liz , Kuney Mary 
Published: July 2005

Background The potential weakness of the open Bankart procedure is the takedown and repair of the subscapularis tendon. It is not known to what extent this part of the procedure affects the final result. Hypothesis The function of the subscapularis muscle after surgery will be related to the patient's perception of surgical success. Study Design Cohort study; Level of evidence, 2. Methods A total of 30 patients with traumatic anterior instability had an open Bankart repair by a single surgeon. These patients were observed for a mean of 4 years. At final follow-up, the patients filled out 3 self-assessment forms: the American Shoulder and Elbow Surgeons scale, the Western Ontario Shoulder Instability Index, and the Constant and Murley scale. An independent physician performed a complete physical examination. Strength testing of all muscle groups was performed and compared with the opposite normal side. Results Multiple factors were related to the patient's perception of the result. Only subscapularis function was found to have a statistically significant correlation. Of the patients, 23% had an incompetent subscapularis with a mean of 27% strength as compared with the opposite side. These patients had a positive lift-off test result and reported 57% good and excellent results; only 57% would have the surgery again. Of the patients, 77% had a normal functioning subscapularis with at least 80% strength as compared with the opposite side. These patients had a negative lift-off test result and had 91% good and excellent results; 100% would have the surgery again. The Western Ontario Shoulder Instability Index was the only scale that differentiated between a patient with subscapularis function and a patient without subscapularis function. Conclusion Postoperative subscapularis function was the most critical factor in determining the patient's perception of surgical success. Clinical Relevance It is likely that handling of the subscapularis tendon during surgery and protection of the subscapularis in the first weeks after surgery are critical to the success of the open Bankart repair.
The Effect of Lateral Cortex Disruption and Repair on the Stability of the Medial Opening Wedge High Tibial Osteotomy
Authors: Miller Bruce S. , Dorsey William O. P. , Bryant Cari R. , Austin John C. 
Published: July 2005

Background Medial opening wedge high tibial osteotomy is gaining popularity as a treatment option for medial compartment degenerative disease in the young, active patient. One of the potential technical pitfalls of this procedure is inadvertent disruption of the lateral tibial cortex during distraction at the osteotomy site. Purpose (1) To investigate the effect of lateral cortex disruption on stability during medial opening wedge high tibial osteotomy and (2) to evaluate 3 different methods of repair of the disrupted lateral cortex. Study Design Controlled laboratory study. Methods A total of 50 validated replicate tibias were evaluated in a medial opening wedge high tibial osteotomy model. Specimens were divided into 5 groups: (1) control, or intact lateral cortex (n = 10); (2) disrupted lateral cortex (n = 10); (3) lateral cortex repaired with 1 staple (n = 10); (4) lateral cortex repaired with 2 staples (n = 10); and (5) lateral cortex repaired with a periarticular plate and screws (n = 10). Specimens were placed in compression and torsion under physiologic loads, and stiffness and micromotion were calculated. Results Disruption of the lateral cortex resulted in a 58% reduction in axial stiffness and a 68% reduction in torsional stiffness compared to control specimens (P<. 05). Disruption of the lateral cortex also resulted in increased micromotion at the osteotomy site. All 3 methods of repair of the lateral cortex restored stiffness and micromotion values to those of the control group (P<. 05). Conclusions Instability at the osteotomy site may contribute to the high rate of delayed union or nonunion associated with medial opening wedge high tibial osteotomy. Repair of the lateral tibial cortex by each of these techniques restored stability to the osteotomy site in this replicate tibia model and might be effective in clinical use. However, more studies are needed to further explore the relationship between lateral cortex disruption and patient outcomes in the clinical setting before definitive conclusions can be drawn.
First-Time Inversion Ankle Ligament Trauma
Authors: Beynnon Bruce D. , Vacek Pamela M. , Murphy Darlene , Alosa Denise , Paller David 
Published: July 2005

Background Inversion ankle trauma is disabling, yet little is known regarding the incidence rate of first-time ankle sprains and how it is influenced by factors including sex, level of competition, and sport. Hypothesis The incidence rates of first-time ankle ligament sprains are influenced by sex, level of competition (high school vs college), and type of sports participation (basketball, soccer, lacrosse, and field hockey). Study Design Cohort study; Level of evidence, 2. Methods Between 1999 and 2003, high school and college athletes were evaluated before participation in their sports. Subjects were included in the study if they had not experienced a prior ankle or lower extremity injury and were then followed during participation in soccer, basketball, lacrosse, or field hockey to document their days of exposure to sport and injuries sustained. The relative risk associated with sex, level of competition, and sport was estimated by Cox regression. Results A total of 901 athletes had 50 680 person-days of exposure to sports, and 43 (4.8%) had an inversion injury that produced an ankle ligament sprain. Overall, the injury incidence rate was 0.85 sprains per 1000 person-days of exposure to sport. There were 0.68 and 0.97 ankle sprains per 1000 person-days of exposure to sport for the men and women, respectively. Although the risk of suffering an ankle sprain was higher for women than for men (relative risk, 1.51), the difference was not statistically significant (P=. 21) and was owing to the increased risk in female basketball athletes compared to male basketball athletes (relative risk, 4.11; P=. 045). Risk of injury was similar for the high school athletes in comparison to the college athletes (relative risk, 1.16). For the men, there was no difference in the risk of suffering an ankle sprain between the sports of basketball, soccer, and lacrosse, whereas for the women, the risk of suffering an ankle sprain was significantly greater during participation in basketball compared to lacrosse. Conclusion In this study of first-time ankle sprains, for most sports, the incidence rate of inversion injury is less than 1 per 1000 days of exposure to sport, a value lower than previously reported. Among female athletes, ankle injury is associated with type of sport. Risk is highest for female basketball athletes, who are at significantly greater risk than male basketball athletes and female lacrosse athletes. The risk of first-time ankle injury is similar for high school and college-level athletes.
Team Physicians in College Athletics
Authors: Steiner Mark E. , Quigley D. Bradford , Wang Frank , Balint Christopher R. , Boland Arthur L. 
Published: July 2005

Background There has been little documentation of what constitutes the clinical work of intercollegiate team physicians. Team physicians could be recruited based on the needs of athletes. Hypothesis A multidisciplinary team of physicians is necessary to treat college athletes. Most physician evaluations are for musculoskeletal injuries treated nonoperatively. Study Design Descriptive epidemiology study. Methods For a 2-year period, a database was created that recorded information on team physician encounters with intercollegiate athletes at a major university. Data on imaging studies, hospitalizations, and surgeries were also recorded. The diagnoses for physician encounters with all undergraduates through the university's health service were also recorded. Results More initial athlete evaluations were for musculoskeletal diagnoses (73%) than for general medical diagnoses (27%) (P<. 05). Four percent of musculoskeletal injuries required surgery. Most general medical evaluations were single visits for upper respiratory infections and dermatologic disorders, or multiple visits for concussions. Football accounted for 22% of all physician encounters, more than any other sport (P<. 05). Per capita, men and women sought care at an equal rate. In contrast, 10% of physician encounters with the general pool of undergraduates were for musculoskeletal diagnoses. Student athletes did not require a greater number of physician encounters than did the general undergraduate pool of students on a per capita basis. Conclusion Intercollegiate team physicians primarily treat musculoskeletal injuries that do not require surgery. General medical care is often single evaluations of common conditions and repeat evaluations for concussions.
DCD – a novel plant specific domain in proteins involved in development and programmed cell death
Authors: Tenhaken Raimund , Doerks Tobias , Bork Peer 
Published: July 2005

Abstract
Background
Recognition of microbial pathogens by plants triggers the hypersensitive reaction, a common form of programmed cell death in plants. These dying cells generate signals that activate the plant immune system and alarm the neighboring cells as well as the whole plant to activate defense responses to limit the spread of the pathogen. The molecular mechanisms behind the hypersensitive reaction are largely unknown except for the recognition process of pathogens. We delineate the NRP-gene in soybean, which is specifically induced during this programmed cell death and contains a novel protein domain, which is commonly found in different plant proteins.

Results
The sequence analysis of the protein, encoded by the NRP-gene from soybean, led to the identification of a novel domain, which we named DCD, because it is found in plant proteins involved in d evelopment and c ell d eath. The domain is shared by several proteins in the Arabidopsis and the rice genomes, which otherwise show a different protein architecture. Biological studies indicate a role of these proteins in phytohormone response, embryo development and programmed cell by pathogens or ozone.

Conclusion
It is tempting to speculate, that the DCD domain mediates signaling in plant development and programmed cell death and could thus be used to identify interacting proteins to gain further molecular insights into these processes.
Tim50a, a nuclear isoform of the mitochondrial Tim50, interacts with proteins involved in snRNP biogenesis
Authors: Xu Hongzhi , Somers Z Brad , Robinson Melvin L , Hebert Michael D 
Published: July 2005

Abstract

Background
The Cajal body (CB) is a nuclear suborganelle involved in the biogenesis of small nuclear ribonucleoproteins (snRNPs), which are vital for pre-mRNA splicing. Newly imported Sm-class snRNPs traffic through CBs, where the snRNA component of the snRNP is modified, and then target to other nuclear domains such as speckles and perichromatin fibrils. It is not known how nascent snRNPs localize to the CB and are released from this structure after modification. The marker protein for CBs, coilin, may play a role in snRNP biogenesis given that it can interact with snRNPs and SMN, the protein mutated in Spinal Muscular Atrophy. Loss of coilin function in mice leads to significant viability and fertility problems and altered CB formation.

Results
In this report, we identify a minor isoform of the mitochondrial Tim50, Tim50a, as a coilin interacting protein. The Tim50a transcript can be detected in some cancer cell lines and normal brain tissue. The Tim50a protein differs only from Tim50 in that it contains an additional 103 aa N-terminal to the translation start of Tim50. Importantly, a putative nuclear localization signal is found within these 103 residues. In contrast to Tim50, which localizes to the cytoplasm and mitochondria, Tim50a is strictly nuclear and is enriched in speckles with snRNPs. In addition to coilin, Tim50a interacts with snRNPs and SMN. Competition binding experiments demonstrate that coilin competes with Sm proteins of snRNPs and SMN for binding sites on Tim50a.

Conclusion
Tim50a may play a role in snRNP biogenesis given its cellular localization and protein interaction characteristics. We hypothesize that Tim50a takes part in the release of snRNPs and SMN from the CB.
Predictors and prognosis of paroxysmal atrial fibrillation in general practice in the UK
Authors: Ruigómez Ana , Johansson Saga , Wallander Mari-Ann , García Rodríguez Luis Alberto 
Published: July 2005

Abstract

Background
Natural history of paroxysmal atrial fibrillation (AF) is not very well documented. Clinical experience suggests that paroxysmal AF could progress to chronic AF with estimates ranging between 15 and 30% over a period of 1–3 years. We performed an epidemiologic study to elucidate the natural history of paroxysmal AF, this study estimated its incidence in a general practice setting, identified associated factors and analyzed the progression into chronic AF as well as the mortality rate.

Methods
Using the UK General Practice Research Database (GPRD), we identified patients aged 40–89 years with a first-recorded episode of paroxysmal AF during 1996. Risk factors were assessed using 525 incident paroxysmal AF cases confirmed by the general practitioner (GP) and a random sample of controls. We follow-up paroxysmal AF patients and estimated their mortality rate and progression to chronic AF.

Results
The incidence of paroxysmal AF was 1.0 per 1,000 person-years. Major risk factors for paroxysmal AF were age and prior valvular heart disease, ischaemic heart disease, heart failure and hyperthyroidism. During a mean follow-up of 2.7 years, 70 of 418 paroxysmal AF patients with complete information progressed to chronic AF. Risk factors associated with progression were valvular heart disease (OR 2.7, 95% CI 1.2–6.0) and moderate to high alcohol consumption (OR 3.0, 95% CI 1.1–8.0). Paroxysmal AF patients did not carry an increased risk of mortality, compared to an age and sex matched sample of the general population. There was a suggestion of a small increased risk among patients progressing to chronic AF (RR 1.5, 96% CI 0.8–2.9).

Conclusion
Paroxysmal AF is a common arrhythmia in the general practice setting, increasing with age and commonly associated with other heart diseases. It sometimes is the initial presentation and then progress to chronic AF. A history of valvular heart disease and alcohol consumption are associated with this progression.
The impact of illness in patients with moderate to severe gastro-esophageal reflux disease
Authors: El-Dika Samer , Guyatt Gordon H , Armstrong David , Degl'innocenti Alessio , Wiklund Ingela , Fallone Carlo A , Tanser Lisa , van Zanten Sander Veldhuyzen , Heels-Ansdell Diane , Wahlqvist Peter , Chiba Naoki , Barkun Alan N , Austin Peggy , Schünemann Holger J 
Published: July 2005

AbstractBackgroundGastro-esophageal reflux disease (GERD) is a common disease. It impairs health related quality of life (HRQL). However, the impact on utility scores and work productivity in patients with moderate to severe GERD is not well known.MethodsWe analyzed data from 217 patients with moderate to severe GERD (mean age 50, SD 13.7) across 17 Canadian centers. Patients completed three utility instruments – the standard gamble (SG), the feeling thermometer (FT), and the Health Utilities Index 3 (HUI 3) – and several HRQL instruments, including Quality of Life in Reflux and Dyspepsia (QOLRAD) and the Medical Outcomes Short Form-36 (SF-36). All patients received a proton pump inhibitor, esomeprazole 40 mg daily, for four to six weeks.ResultsThe mean scores on a scale from 0 (dead) to 1 (full health) obtained for the FT, SG, and HUI 3 were 0.67 (95% CI, 0.64 to 0.70), 0.76 (95% CI, 0.75 to 0.80), and 0.80 (95% CI, 0.77 to 0.82) respectively. The mean scores on the SF-36 were lower than the previously reported Canadian and US general population mean scores and work productivity was impaired.ConclusionGERD has significant impact on utility scores, HRQL, and work productivity in patients with moderate to severe disease. Furthermore, the FT and HUI 3 provide more valid measurements of HRQL in GERD than the SG. After treatment with esomeprazole, patients showed improved HRQL.
Influence of electrical and thermal properties on RF ablation of breast cancer: is the tumour preferentially heated?
Authors: Ekstrand Vilhelm , Wiksell Hans , Schultz Inkeri , Sandstedt Bengt , Rotstein Samuel , Eriksson Anders 
Published: July 2005

Abstract

Background
Techniques based on radio frequency (RF) energy have many applications in medicine, in particular tumour ablation. Today, mammography screening detects many breast cancers at an early stage, facilitating treatment by minimally invasive techniques such as radio frequency ablation (RFA). The breast cancer is mostly surrounded by fat, which during RFA-treatment could result in preferential heating of the tumour due to the substantial differences in electrical parameters. The object of this study was to investigate if this preferential heating existed during experimental in vitro protocols and during computer simulations.

Methods
Excised breast material from four patients with morphologically diagnosed breast cancers were treated with our newly developed RFA equipment. Subsequently, two finite element method (FEM) models were developed; one with only fat and one with fat and an incorporated breast cancer of varying size. The FEM models were solved using temperature dependent electrical conductivity versus constant conductivity, and transient versus steady-state analyses.

Results
Our experimental study performed on excised breast tissue showed a preferential heating of the tumour, even if associated with long tumour strands. The fat between these tumour strands was surprisingly unaffected. Furthermore, the computer simulations demonstrated that the difference in electrical and thermal parameters between fat and tumour tissue can cause preferential heating of the tumour. The specific absorption rate (SAR) distribution changed significantly when a tumour was present in fatty tissue. The degree of preferential heating depended on tissue properties, tumour shape, and placement relative to the electrode. Temperature dependent electrical conductivity increased the thermal lesion volume, but did not change the preferential heating. Transient solutions decreased the thermal lesion volume but increased the preferential heating of the tumour.

Conclusion
Both the computer model and the in vitro study confirmed that preferential heating of the tumour during RFA exists in breast tissue. However, the observed preferential heating in the in vitro studies were more pronounced, indicating that additional effects other than the difference in tissue parameters might be involved. The existing septa layers between the cancer tissue and the fatty tissue could have an additional electrical or thermal insulating effect, explaining the discrepancy between the in vitro study and the computer model.