bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of a nitinol stent to palliate a colorectal neoplastic obstruction in a dog
Authors: Culp William T. N. , MacPhail Catriona M. , Perry James A. , Jensen Tracey D. 
Published: July 2011

Abstract
Case Description—A 12-year-old castrated male Labrador Retriever was evaluated for clinical signs associated with colorectal obstruction.
Clinical Findings—The dog had a 2-week history of tenesmus and hematochezia. On rectal examination, an annular colorectal mass was palpable extending orad into the pelvic canal. The original diagnosis of the colorectal mass was a mucosal adenoma. The dog was maintained on a low-residue diet and fecal softeners for a period of 13 months after initial diagnosis. At that time, medical management was no longer effective.
Treatment and Outcome—Placement of a colonic stent was chosen to palliate the clinical signs associated with colorectal obstruction. By use of fluoroscopic and colonoscopic guidance, a nitinol stent was placed intraluminally to open the obstructed region. Placement of the stent resulted in improvement of clinical signs, although tenesmus and obstipation occurred periodically after stent placement. At 212 days after stent placement, the patient had extensive improvement in clinical signs with minimal complications; however, clinical signs became severe at 238 days after stent placement, and the dog was euthanized. Histologic evaluation of the rectal tumor from samples obtained during necropsy revealed that the tumor had undergone malignant transformation to a carcinoma in situ.
Clinical Relevance—A stent was successfully placed in the colon and rectum to relieve obstruction associated with a tumor originally diagnosed as a benign neoplasm. Placement of colorectal stents may be an option for the palliation of colorectal obstruction secondary to neoplastic disease; however, clinical signs may persist, and continuation of medical management may be necessary.
A category Ψ-density topology
Authors: Wilczyński Władysław , Wojdowski Wojciech 
Published: July 2011

Abstract
Ψ-density point of a Lebesgue measurable set was introduced by Taylor in [Taylor S.J., On strengthening the Lebesgue Density Theorem, Fund. Math., 1958, 46, 305–315] and [Taylor S.J., An alternative form of Egoroff’s theorem, Fund. Math., 1960, 48, 169–174] as an answer to a problem posed by Ulam. We present a category analogue of the notion and of the Ψ-density topology. We define a category analogue of the Ψ-density point of the set A at a point x as the Ψ-density point at x of the regular open representation of A.
Method of Power System Suistanable Development Optimization in Liberalized Market Conditions
Authors: Turcik M. , Oleinikova I. , Krishans Z. 
Published: July 2011

Method of Power System Suistanable Development Optimization in Liberalized Market Conditions
The paper is focused on the development of the Baltic Sea region taking into account the new EU energy policy. The authors elucidate the current situation and the power system infrastructure projects of the region. For the economic analysis and optimization of the development plans a method is proposed that takes into account the outlooks for upcoming 20-50 years and the initial information uncertainty. The method makes possible estimation of the technically-economic state, including market conditions, for a given power system.
Epidemiology and Outcomes of Acute Achilles Tendon Rupture with Operative or Nonoperative Treatment Using an Identical Functional Bracing Protocol
Authors: Gwynne-Jones David P. , Sims Martyn 
Published: July 2011

Background: This study reports on the demographics of acute Achilles tendon rupture in our region and compares the results of a selective approach to operative and nonoperative treatment using an identical rehabilitation program with functional bracing. Materials and Methods: A consecutive series of 363 patients, aged 15 to 60 years, treated over 8.5 years by either open operative repair (143) or nonoperatively (220) were compared with respect to demographics, re-rupture rate, and major wound complication. Results: There was an almost equal number of males (159) and females (152) up to age 50 years but males comprised 73% of patients aged 51 to 60 years. Netball was the most common cause of injury and explains the relatively high incidence in females. In the 143 patients treated surgically there were two re-ruptures (1.4%) and two reop-erations for wound complications (1.4%). In the 220 patients treated nonoperatively there were 19 re-ruptures (8.6%), 13 of 113 males (11.5%) and six of 107 females (5.6%). There was a significantly lower re-rupture rate, and reoperation rate in the surgical group ( p < 0.05). In the nonoperative group there was a significantly lower rate of re-rupture in patients over 40 (six of 119) (4.1%) compared with those 40 years and under (13 of 99, 13.1%) and between females over 40 when compared with males 40 years and under. Conclusion: In our region there is a high incidence of Achilles tendon rupture among women due to netball and results in a younger age of injury than previously reported. Our results support surgery in patients less than 40 years, particularly males, if there are no contraindications. Functional bracing as part of nonoperative treatment can result in low re-rupture rates in patients over 40, especially in females. Level of Evidence: III, Retrospective Comparative Study
Functional Outcome of Matrix-Associated Autologous Chondrocyte Implantation in the Ankle
Authors: Dixon Sean , Harvey Leigh , Baddour Edward , Janes Greg , Hardisty Gerard 
Published: July 2011

Background: The technique of Matrix-associated autologous chondrocyte implantation (MACI) is well established with satisfactory outcomes up to 5 years in the knee. Fewer series describe the outcomes of this technique in the ankle. We present the functional outcomes of the technique for a single surgeon series in a general hospital setting. Materials and Methods: Twenty-seven patients, mean age 41, were reviewed at 3.7 (range, 1 to 5) years. Patients were assessed using the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot scale, Tegener activity score and University of California lower extremity activity scale. MRI findings were also reviewed. Results: While most patients report a significant improvement in symptoms with full return to activities of daily living, 36% of those under 40 and 78% of those over 40 reported restricted recreational activity. Of the patients under 40 years of age, 86% were able to run compared with 23% of those over 40. Of patients over 40, 64% continued to have moderate or severe pain. Conclusion: Careful preoperative counseling is required for patients of all ages regarding likely outcomes. In patients over 40, the procedure is unlikely to give good pain relief and alternative options should be considered. Level of Evidence: IV, Case Series
Osteochondral Autograft Transplantation for Acute Osteochondral Fractures Associated with an Ankle Fracture
Authors: Liu Wanjun , Liu Fang , Zhao Wen , Kim Jaehon M. , Wang Zhenghai , Vrahas Mark S. 
Published: July 2011

Background: Osteochondral fractures of the talar dome (OCFT) are frequently associated with ankle fractures. Controversy exists regarding the treatment of acute Grade III and IV OCFT. Osteochondral autograft transplantation (OAT) is a possible operative solution. Materials and Methods: We performed OAT in 16 patients with acute Grade III or IV OCFT. There were ten males and six females with the average age of 33.9 (range, 18 to 49) years. The average period of followup was 36.3 (range, 21 to 48) months. OCFT was identified, and clinically determined to be Grade III or IV using radiographs and intraoperative assessment. Seven patients were Grade III, nine patients were Grade IV OCFT. The OAT consisted of two sequential procedures: 1) harvesting of osteochondral autograft cylinder from the nonweightbearing surface of the ipsilateral knee, and 2) implanting the donor graft into the talar defect with press-fit technique. Single cylinder transplantation or a mosaicplasty was used. The outcome was determined by the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale, the simplified symptomatology evaluation, plain radiography and MRI. Results: The mean size of the osteochonral fracture defects was 84.1 (range, 50 to 125) mm2, and the mean depth was 2.5 (range, 1 to 5) mm. The mean AOFAS score was 95.4 (range, 86 to 100) points postoperatively. At the latest followup, there was no radiographic evidence of post-traumatic arthritis. Based on the MRI of all patients, 93.7% of the osteochondral grafts showed bony integration and articular congruity of the talar dome. Conclusion: OAT was shown to be an effective treatment with excellent clinical outcome and imaging evidence of graft integration.
Effect of a Steel Toe Cap on Forefoot Injury Pattern in a Cadaveric Model
Authors: Kwon John Y. , Campbell John T. , Myerson Mark S. , Jeng Cliff L. 
Published: July 2011

Background: Crush injuries to the foot are a common workplace injury and a significant source of morbidity, disability and lost wages. Many regulatory bodies including the Occupational Safety and Health Administration (OSHA) recommend the use of safety shoes in certain occupations to help protect against these occupational hazards. However there remains controversy and paucity of published data regarding the protection afforded by a steel toe cap in regards to clinical injury pattern. This study looks to investigates the protective influence of a steel toe cap on crush injuries of the forefoot. Materials and Methods: Five non-osteoporotic paired cadaver lower extremities were appropriately fitted to a standard work boot. One foot of each pair was fitted into a steel toe capped boot (designated “ST” group) while the other foot was fitted into an identical version of the work boot but without the protective steel toe cap (designated “NST” group). Each foot was crushed using a custom designed rig with a load of 150 lb dropped from a calibrated height of 3 feet to the forefoot. X-rays were obtained to assess fracture location & comminution and stress fluoroscopy was used to assess for any ligamentous Lisfranc injury. Results: The NST group averaged 8.2 fractured bones per foot while the ST group averaged 3.6 fractured bones per foot ( p = 0.001). The NST group demonstrated significantly more metatarsal fractures (3.2 fractures/foot) versus the ST group (one fracture/foot) ( p= 0.020). The NST group demonstrated significantly more proximal phalanx fractures (4.2 fractures/foot) compared to the ST group (2.6 fractures/foot) ( p= 0.035). Middle and distal phalanx fractures were not significantly different between the two groups. A higher percentage of the bones fractured were deemed comminuted in the NST group (53.6%) versus the ST group (38.8%) although this did not reach statistical significance. Conclusion: This study demonstrated that the steel toe affords protective advantages in crush injuries to the foot in limiting the number and severity of metatarsal and proximal phalanx fractures. However the steel toe does not fully protect the forefoot from injury. Clinical Relevance: Crush injuries to the foot are a common workplace injury. Strict adherence to workplace safety standards may limit the severity of crush injuries to the foot and additional safety measures such as metatarsal guards should be considered when appropriate.
The Fate of Syndesmotic Screws
Authors: Stuart Kyle , Panchbhavi Vinod K. 
Published: July 2011

Background: A standard protocol for the management of syndesmosis injuries has yet to be established. Debate persists regarding number of screws, screw diameter, number of cortices purchased, and the need for and timing of screw removal. The purpose of this study was to identify factors related to screw fixation that may lead to the ultimate failure of syndesmosis fixation defined as a loss of reduction of the syndesmosis, screw breakage, screw loosening, or widening of the medial clear space. Materials and Methods: A retrospective assessment of 137 consecutive patients who underwent open reduction and internal fixation of the distal tibiofibular joint at a single institution from 2004 to 2008 was performed. Clinical and radiographic data were recorded regarding problems with questionable clinical significance (number of syndesmotic screws, number of cortices, screw diameter, screw location, hardware failure) and loss of syndesmosis reduction. A series of Fisher's exact tests were used to evaluate outcomes. A p value of 0.05 defined as significant. Results: The 3.5-mm diameter screws were statistically more likely to break than 4- or 4.5-mm screws, but there was no difference in frequency of loss of reduction of the syndesmosis as a function of screw diameter; however, a power study revealed an n value of 1656 would be required to show a significant difference. Conclusion: Screw diameter may have an effect on screw breakage but clinical significance of hardware failure itself is unknown including whether or not it results in a loss of reduction or failure of syndesmotic fixation. Level of Evidence: III, Retrospective Comparative Study
Augmented Tendon Achilles Repair Using a Tissue Reinforcement Scaffold: A Biomechanical Study
Authors: Giza Eric , Frizzell Lauren , Farac Randall , Williams Joel , Kim Sunny 
Published: July 2011

Background: Missed or chronic Achilles tendon ruptures may have muscle atrophy and tendon retraction resulting in a defect that must be augmented with endogenous or exogenous materials. The Artelon® Tissue Reinforcement (ATR) scaffold is a readily available synthetic degradable poly(urethane urea) material used to augment tendon repair. The objective of this study was to compare human cadaveric Achilles tendon repairs with and without ATR. Materials and Methods: Eighteen fresh frozen human cadaver limbs were dissected and the tendon transected 2 cm proximal to the calcaneal insertion. The control group of nine specimens was repaired with sutures, while the experimental group was repaired with sutures and reinforced with a tubularized patch of ATR. Specimens were tested for ultimate load to failure in an Instron machine after preloading to 10 N followed by cyclic loading for 20 cycles from 2 to 30 N. Results: The ultimate load to failure in the control group was a mean of 248.1 N ± 19.6 (202 to 293 at 95% CI) versus 370.4 N ± 25.2 (312 to 428 at 95% CI) in the ATR group. The ultimate load to failure was 370.4 ± 25.2 N (312 to 428 at 95% CI) and 248.1 ± 19.6 N (202 to 293 at 95% CI) in the experimental and control groups, respectively (p = 0.0015). Creep of the ATR augmented group was 2.0 ± 0.5 mm, compared to 3.1 ± 1.1 mm for the control group (p = 0.026). Conclusion: ATR provided a statistically significant improvement in load to failure when compared to control specimens in a cadaver model. Clinical Relevance: This finding may allow for development of more aggressive rehabilitation techniques following chronic Achilles tendon repairs.
A critical evaluation of cystic features in primary glioblastoma as a prognostic factor for survival
Authors: Kaur Gurvinder , Bloch Orin , Jian Brian J. , Kaur Rajwant , Sughrue Michael E. , Aghi Manish K. , McDermott Michael W. , Berger Mitchel S. , Chang Susan M. , Parsa Andrew T. 
Published: July 2011

Object
The presence of cystic features in glioblastoma (GBM) has been described as a favorable prognostic factor. The aim of this study was to determine the survival outcome in patients undergoing surgery for newly diagnosed primary GBM with a large cystic component as compared with a large cohort of patients with noncystic GBM, while controlling for well-characterized prognostic factors.

Methods
A retrospective review of 354 consecutive patients treated with resection of primary GBM was performed using medical records and imaging information obtained at the University of California, San Francisco from 2005 to 2009. Within this cohort, 37 patients with large cysts (≥ 50% of tumor) were identified. Clinical presentations and surgical outcomes were statistically compared between the cystic and noncystic patients.

Results
There were no statistically significant differences in clinical presentation between groups, including differences in age, sex, presenting symptoms, tumor location, or preoperative functional status, with the exception of tumor size, which was marginally larger in the cystic group. Surgical outcomes, including extent of resection and postoperative functional status, were equivalent. The median actuarial survival for the patients with cystic GBM was 17.0 months (95% CI 12.6–21.3 months), and the median survival for patients with noncystic GBM was 15.9 months (95% CI 14.6–17.2 months). There was no significant between-groups difference in survival (p = 0.99, log-rank test). A Cox multivariate regression model was constructed, which identified only age and extent of resection as independent predictors of survival. The presence of a cyst was not a statistically significant prognostic factor.

Conclusions
This study, comprising the largest series of cases of primary cystic GBM reported in the literature to date, demonstrates that the presence of a large cyst in patients with GBM does not significantly affect overall survival as compared with survival in patients without a cyst. Preoperative discussions with patients with GBM should focus on validated prognostic factors. The presence of cystic features does not confer a survival advantage.
Expression of carbonic anhydrase IX in craniopharyngiomas
Authors: Proescholdt Martin , Merrill Marsha , Stoerr Eva-Maria , Lohmeier Annette , Dietmaier Wolfgang , Brawanski Alexander 
Published: July 2011

Object
In craniopharyngiomas, cystic growth causes pressure on vital structures of the adjacent brain, leading to significant morbidity. However, the molecular pathogenesis of this cyst formation remains unknown. Carbonic anhydrase IX (CA IX) is a tumor-associated, hypoxia-inducible enzyme, which can cause fluid production and development of cysts. The authors investigated CA IX expression in craniopharyngiomas and its correlation with the extent of cyst formation. In addition, the major pathways of CA IX regulation, hypoxia and p53 mutation, were analyzed.

Methods
Expression of CA IX was analyzed in 20 craniopharyngioma patients by means of in situ hybridization and immunohistochemistry. Preoperative imaging was used to quantify cyst volume. To analyze putative hypoxic induction of CA IX, immunohistochemical staining for HIF-1α and VEGF was performed. Since p53 negatively regulates CA IX expression, we also analyzed the tumors for p53 mutation by direct sequencing.

Results
Significant CA IX was found in 85% of the 20 cases. The extent of CA IX expression was significantly correlated with cyst volume. HIF-1α expression was largely absent in all tissue samples, whereas moderate VEGF expression was present in a subset of cases but without correlation to cyst volume. No p53 mutation was found in any of the analyzed tumors.

Conclusions
Carbonic anhydrase IX, which is virtually absent in normal brain, is significantly upregulated in craniopharyngiomas and shows a significant association with cyst size. The mechanisms of regulation remain unknown, since neither hypoxia nor p53 appears to play a role. These results indicate that inhibition of CA IX may be a potential target for the adjuvant treatment in patients with cystic craniopharyngiomas.
Intraoperative, full-rotation, three-dimensional image (O-arm)–based navigation system for cervical pedicle screw insertion
Authors: Ishikawa Yoshimoto , Kanemura Tokumi , Yoshida Go , Matsumoto Akiyuki , Ito Zenya , Tauchi Ryoji , Muramoto Akio , Ohno Shuichiro , Nishimura Yusuke 
Published: July 2011

Object
The aim of this study was to retrospectively evaluate the reliability and accuracy of cervical pedicle screw (CPS) placement using an intraoperative, full-rotation, 3D image (O-arm)–based navigation system and to assess the advantages and disadvantages of the system.

Methods
The study involved 21 consecutive patients undergoing posterior stabilization surgery of the cervical spine between April and December 2009. The patients, in whom 108 CPSs had been inserted, underwent screw placement based on intraoperative 3D imaging and navigation using the O-arm system. Cervical pedicle screw positions were classified into 4 grades, according to pedicle-wall perforations, by using postoperative CT.

Results
Of the 108 CPSs, 96 (88.9%) were classified as Grade 0 (no perforation), 9 (8.3%) as Grade 1 (perforations < 2 mm, CPS exposed, and < 50% of screw diameter outside the pedicle), and 3 (2.8%) as Grade 2 (perforations between ≥ 2 and < 4 mm, CPS breached the pedicle wall, and > 50% of screw diameter outside the pedicle). No screw was classified as Grade 3 (perforation > 4 mm, complete perforation). No neurovascular complications occurred because of CPS placement.

Conclusions
The O-arm offers high-resolution 2D or 3D images, facilitates accurate and safe CPS insertion with high-quality navigation, and provides other substantial benefits for cervical spinal instrumentation. Even with current optimized technology, however, CPS perforation cannot be completely prevented, with 8.3% instances of minor violations, which do not cause significant complications, and 2.8% instances of major pedicle violations, which may cause catastrophic complications. Therefore, a combination of intraoperative 3D image–based navigation with other techniques may result in more accurate CPS placement.
A simple and updated pneumatic method for uniaxial ice compression in the laboratory: experimental settings and creep test results on glacier ice
Authors: Samyn D. , Dierckx M. , Remy J.-P. , Goossens T. , Tison J.-L. 
Published: July 2011

AbstractCreep tests provide invaluable data to better understand the physical properties of ice under various conditions. We describe here a simple, updated pneumatic apparatus for experimental studies of ice rheological properties. The apparatus is designed to perform two simultaneous compression creep tests either in a cold room or in atmospheric conditions when coupled to an external cooling circulator. We present results from calibration tests of the apparatus and provide new data from creep tests performed on temperate glacier ice samples. These calibration and creep results show that the apparatus is able to provide fast and reliable mechanical ice characterization. The secondary creep rates measured in this study range between 1.59 × 10−8 s−1 (at 0.21 MPa) and 4.38 × 10−7 s−1 (at 0.71 MPa) at −10°C for quasi-isotropic ice, which is consistent with former standard published data. The corresponding mean parameter, A, is 5.20 × 10−16 s−1 kPa−3, which also compares well with the range of reported other studies.