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Mesenchymal stem cells for treating articular cartilage defects and osteoarthritis.  

Science.gov (United States)

Articular cartilage damage and osteoarthritis are the most common joint diseases. Joints are prone to damage caused by sports injuries or aging, and such damage regularly progresses to more serious joint disorders, including osteoarthritis, which is a degenerative disease characterized by the thinning and eventual wearing-out of articular cartilage, ultimately leading to joint destruction. Osteoarthritis affects millions of people worldwide. Current approaches to repair of articular cartilage damage include mosaicplasty, microfracture, and injection of autologous chondrocytes. These treatments relieve pain and improve joint function, but the long-term results are unsatisfactory. The long-term success of cartilage repair depends on development of regenerative methodologies that restore articular cartilage to a near-native state. Two promising approaches are (i) implantation of engineered constructs of mesenchymal stem cell (MSC)-seeded scaffolds, and (ii) delivery of an appropriate population of MSCs by direct intra-articular injection. MSCs may be used as trophic producers of bioactive factors initiating regenerative activities in a defective joint. Current challenges in MSC therapy are the need to overcome current limitations in cartilage cell purity, and to in vitro engineer tissue structures exhibiting the required biomechanical properties. This review outlines the current status of MSCs used in cartilage tissue engineering, and in cell therapy seeking to repair articular cartilage defects and related problems. MSC-based technologies show promise when used to repair cartilage defects in joints. PMID:25197793

Wang, Yu; Yuan, Mei; Guo, Quan-Yi; Lu, Shi-Bi; Peng, Jiang

2014-07-25

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Focal defect resembling a subchondral bone cyst of the ulnar trochlear notch in a dog.  

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A 13 mo old spayed female golden retriever/standard poodle mixed-breed dog was presented for intermittent right forelimb lameness. Physical examination revealed marked effusion and decreased flexion in the right elbow joint, radiography showed mild osteophytosis of the right elbow joint, and computed tomography showed a focal defect in the subchondral bone in the trochlear notch of the ulna resembling a subchondral bone cyst. Arthroscopy of the affected elbow revealed a focal defect in the articular cartilage on the trochlear notch with vascular ingrowth covering a defect in the subchondral bone plate. The synovium surrounding the defect was inflamed. To the authors' knowledge, this is the first published report of a subchondral bone cyst in the ulna of a dog. PMID:25415218

Makielski, Kelly; Muir, Peter; Bleedorn, Jason

2015-01-01

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Repair of articular cartilage defects with collagen-chondrocyte allografts.  

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This study was designed to evaluate the potential use of a prototype collagen-chondrocyte allograft in the repair of full-thickness articular cartilage defects. Articular cartilage was harvested from young donor New Zealand White rabbits, enzymatically digested, cultured in monolayer, and passed into a three-dimensional porous type I collagen sponge (American Biomaterials). The composite grafts were incubated for 1 week. (Phase I) Twenty adult NZW rabbits underwent bilateral knee arthrotomies. Three-millimeter full-thickness articular cartilage defects were made in the trochlea of the distal femur. A 4-mm circular punch from the composite cell-seeded grafts was press-fit into the right knee defects. The left knee served as a control (collagen sponge alone or ungrafted defect). Animals were allowed free activity postoperatively and were killed in groups of five at 4, 8, 12, and 24 weeks postoperatively. Defect areas were harvested. Sections were cut at 5-microm thickness and stained with hematoxylin and eosin. The degree as well as quality of healing were assessed and scored with a grading system modified from Salter and O'Driscoll for cartilage repair. (The maximum score was 24 points.) Safranin-O staining as well as polarized light examination of representative sections was undertaken to assess the proteoglycan content and structural characteristics of the repair matrix. (Phase II) An additional 15 NZW rabbits underwent the above procedure but with the addition of fibroblast growth factor (FGF) (100 ng/ml) and insulin (5 microg/ml) to the growth medium of the composite grafts as stimulators of chondrocyte proliferation and proteoglycan synthesis. Control specimens in phase I and II (collagen sponge alone or ungrafted defects) healed with a primarily fibrous or fibrocartilagenous matrix. Defects grafted with cell-seeded collagen sponges demonstrated enhanced healing at all time points examined when compared to controls. There was a strong tendency toward a hyaline appearing matrix with increased Safranin-O staining and birefringence under polarized light more closely resembling the normal native cartilage. Mean histologic score for grafted defects was 18.4 (+/-3.1). Mean scores for collagen sponge alone and ungrafted defects in phase I were 12.7 (+/-4) and 12.7 (+/-3.1) (P<0.01). The addition of FGF and insulin to the growth medium (phase II) resulted in a significantly enhanced repair matrix when compared to the non-FGF-enhanced grafts, with a greater percentage of hyaline appearing tissue at all time points examined (4,8, and 12 weeks). Organization of the chondrocytes was improved at all time points examined as well. Mean histologic score for the FGF-grafted defects was 21.1 (+/-3.0). Mean scores for collagen sponge alone and ungrafted defects in phase II were 14.9 (+/-2.9) and 15.5 (+/-1.9) (p<0.01). PMID:19877921

Ben-Yishay, A; Grande, D A; Schwartz, R E; Menche, D; Pitman, M D

1995-01-01

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Repair of porcine articular cartilage defect with autologous chondrocyte transplantation.  

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Articular cartilage is known to have poor healing capacity after injury. Autologous chondral grafting remains the mainstay to treat well-defined, full-thickness, symptomatic cartilage defects. We demonstrated the utilization of gelatin microbeads to deliver autologous chondrocytes for in vivo cartilage generation. Chondrocytes were harvested from the left forelimbs of 12 Lee-Sung pigs. The cells were expanded in monolayer culture and then seeded onto gelatin microbeads or left in monolayer. Shortly before implantation, the cell-laden beads were mixed with collagen type I gel, while the cells in monolayer culture were collected and re-suspended in culture medium. Full-thickness cartilage defects were surgically created in the weight-bearing surface of the femoral condyles of both knees, covered by periosteal patches taken from proximal tibia, and sealed with a porcine fibrin glue. In total, 48 condyles were equally allotted to experimental, control, and null groups that were filled beneath the patch with chondrocyte-laden beads in gel, chondrocytes in plain medium solution, or nothing, respectively. The repair was examined 6 months post-surgery on the basis of macroscopic appearance, histological scores based on the International Cartilage Repair Society Scale, and the proportion of characteristic chondrocytes. Tensile stress-relaxation behavior was determined from uniaxial indentation tests. The experimental group scored higher than the control group in the categories of matrix nature, cell distribution pattern, and absence of mineralization, with similar surface smoothness. Both the experimental and control groups were superior to the null group in the above-mentioned categories. Viable cell populations were equal in all groups, but the proportion of characteristic chondrocytes was highest in the experimental group. Matrix stiffness was ranked as null > native cartilage > control > experimental group. Transplanted autologous chondrocytes survive and could yield hyaline-like cartilage. The application of beads and gel for transplantation helped to retain the transferred cells in situ and maintain a better chondrocyte phenotype. PMID:15885479

Chiang, Hongsen; Kuo, Tzong-Fu; Tsai, Chen-Chi; Lin, Mei-Chiao; She, Bin-Ru; Huang, Yi-You; Lee, Hsuan-Shu; Shieh, Chang-Shun; Chen, Min-Huey; Ramshaw, John A M; Werkmeister, Jerome A; Tuan, Rocky S; Jiang, Ching-Chuan

2005-05-01

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Preclinical evaluation of a novel implant for treatment of a full-thickness distal femoral focal cartilage defect.  

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A novel, nonresorbable, monolithic composite structure ceramic, developed using a partially stabilized zirconia ceramic common to implantable devices, was used in a cementless weight-bearing articular implant to test the feasibility of replacing a region of degenerated or damaged articular cartilage in the knee as part of a preclinical study using male mongrel dogs lasting up to 24 weeks. Gross/histological cartilage observations showed no differences among control, 12-week and 24-week groups, while pull-out tests showed an increase in maximum pull-out load over time relative to controls. Hence, the use of a novel ceramic implant as a replacement for a focal cartilage defect leads to effective implant fixation within 12 weeks and does not cause significant degradation in opposing articular cartilage in the time frame evaluated. PMID:23523501

Waldorff, Erik I; Roessler, Blake J; Zachos, Terri A; Miller, Bruce S; McHugh, Jonathan; Goldstein, Steven A

2013-09-01

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Modeling of constrained articular cartilage growth in an intact knee with focal knee resurfacing metal implant.  

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The purpose of the present study was to develop a model to simulate the articular cartilage growth in an intact knee model with a metal implant replacing a degenerated portion of the femoral cartilage. The human knee joint was approximated with a simplified axisymmetric shape of the femoral condyle along with the cartilage, meniscus and bones. Two individually growing constituents (proteoglycans and collagen) bound to solid matrix were considered in the solid phase of the cartilage. The cartilage behavior was modeled with a nonlinear biphasic porohyperelastic material model, and meniscus with a transversely isotropic linear biphasic poroelastic material model. Two criteria (permeation and shear), both driven by mechanical loading, were considered to trigger the growth in the solid constituents. Mechanical loading with sixty heavy cycles was considered to represent daily walking activity. The growth algorithm was implemented for 90 days after implantation. The results from simulations show that both cartilage layers were more stimulated near the implant which lead to more growth of the cartilage near the defect. The method developed in the present work could be a powerful technique if more accurate material data and growth laws were available. PMID:23955432

Manda, Krishnagoud; Eriksson, Anders

2014-06-01

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Focal porta hepatis scintiscan defects: what is their significance  

International Nuclear Information System (INIS)

A total of 537 consecutive liver /sup 99m/Tc-sulfur colloid scintiscans were retrospectively reviewed and 80 of them revealed suspicious focal decreased activity in the region of the porta hepatis. Postmortem, surgical, or biopsy correlation was obtained in 40 of these cases: 14 were pathologically negative; 9, cirrhosis or fibrosis; 10, metastases; 3, dilated bile ducts; 1, viral hepatitis; 1, hepatic laceration; 1, falciform ligament cyst; and 1, ruptured gallbladder with abscessed head of the pancreas. Thus, only 42 percent represented significant disease. Sixty-eight percent of the defects were seen only on the anterior scintiscan. Appearance of the majority of defects was nonspecific. Subjective grading of defects according to size and comparative decrease in density was not beneficial. Elevations of serum alkaline phosphatase, total serum bilirubin, and serum glutamic-oxalacetic transaminase were nonspecific

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Biomaterials and Tissue Engineering for Regenerative Repair of Articular Cartilage Defects  

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Full Text Available Articular cartilage defects heal very poorly and lead to degenerative arthritis. Existing medications cannot promote healing process; cartilage defects eventually require surgical replacements with autografts. As there is not enough source of articular cartilage that can be donated for autografting, materials that promote cartilage regeneration are important in both research and clinical applications. Tissue engineering involves cell growth on biomaterial scaffolds in vitro. These cells are then injected into cartilage defects for biological in vivo regeneration of the cartilage tissue. This review aims first to provide a brief introduction to the types of materials in medicine (biomaterials, to their roles in treatment of diseases, and to design factors and general requirements of biomaterials. Then, it attempts to sum up the recent advances in engineering articular cartilage; one of the most challenging area of study in biomaterials based tissue engineering, as an example to the research on regenerative solutions to musculoskeletal problems with an emphasis on the biomaterials that have been developed as scaffolds for cartilage tissue engineering. The definitive goal on cartilage regeneration is to develop a system using biomimetic approach to produce cartilage tissue that mimics native tissue properties, provides rapid restoration of tissue function, and is clinically translatable. This is obviously an ambitious goal; however, significant progress have been made in recent years; and further advances in materials design and technology will pave the way for creating significantly custom-made cellular environment for cartilage regeneration.

Kâz?m Tur

2009-12-01

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Repair of articular cartilage in rabbit osteochondral defects promoted by extracorporeal shock wave therapy  

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This study investigated the stimulative effect of extracorporeal shock wave therapy (ESWT) on the articular cartilage regeneration in the rabbit osteochondral defect model for the first time. An osteochondral defect, 3 mm in diameter and 3 mm in depth, was drilled in the patellar groove at the distal end of each femur in 24 mature New Zealand rabbits. The right patellar defects received 500 impulses of shock waves of 1.2 { mJ}/{mm}2 (at 14 kV) at 1 week after surgery and were designated as the experimental samples; the left patellar defects served as control. At 4, 8, and 12 weeks after ESWT, cartilage repair was evaluated macroscopically and histologically using a semiquantitative grading scale. The total scores of the macroscopic evaluation at 4, 8, and 12 weeks in the experimental group were superior to those in the control group (statistical significance level P ESWT, especially at the early stage. The easy and safe ESWT is potentially viable for clinical application.

Chu, C.-H.; Yen, Y.-S.; Chen, P.-L.; Wen, C.-Y.

2014-05-01

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Ongoing studies of cell-based therapies for articular cartilage defects in Japan  

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Full Text Available Takahiro Ogura,1 Akihiro Tsuchiya,2 Shuichi Mizuno1 1Department of Orthopedic Surgery, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA; 2Funabashi Orthopaedic Hospital Sports Medicine Center, Funabashi, Chiba, Japan Abstract: Recently, cell-based therapies have generated great interest in the repair of articular cartilage defects and degeneration. Surgical treatments for these indications have multiple options, including marrow stimulation, osteochondral autograft transplant, and autologous chondrocyte implantation. The autologous chondrocyte implantation technique has been improved using a cell scaffold and other devices. Meanwhile, advanced cell-based therapies, including cultured stem cell treatment, have been studied in clinical trials. Most studies have been designed and authorized by institutional review boards and/or the regulatory agencies of the investigators’ countries. For cellular products in regenerative medicine, regulations of many countries are amenable to expedited approval. This paper aims to provide an update on ongoing and prospective cell-based therapies, focusing on articular cartilage injury at designated institutions authorized by the Japanese Pharmaceutical and Medical Device Agency. Keywords: autologous chondrocyte implantation, mesenchymal stem cell, knee joint

Ogura T

2014-12-01

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Study on nano-structured hydroxyapatite/zirconia stabilized yttria on healing of articular cartilage defect in rabbit  

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Full Text Available PURPOSE: Articular Cartilage has limited potential for self-repair and tissue engineering approaches attempt to repair articular cartilage by scaffolds. We hypothesized that the combined hydroxyapatite and zirconia stabilized yttria would enhance the quality of cartilage healing. METHODS: In ten New Zealand white rabbits bilateral full-thickness osteochondral defect, 4 mm in diameter and 3 mm depth, was created on the articular cartilage of the patellar groove of the distal femur. In group I the scaffold was implanted into the right stifle and the same defect was created in the left stifle without any transplant (group II. Specimens were harvested at 12 weeks after implantation, examined histologically for morphologic features, and stained immunohistochemically for type-II collagen. RESULTS: In group I the defect was filled with a white translucent cartilage tissue In contrast, the defects in the group II remained almost empty. In the group I, the defects were mostly filled with hyaline-like cartilage evidenced but defects in group II were filled with fibrous tissue with surface irregularities. Positive immunohistochemical staining of type-II collagen was observed in group I and it was absent in the control group. CONCLUSION: The hydroxyapatite/yttria stabilized zirconia scaffold would be an effective scaffold for cartilage tissue engineering.

Amir Sotoudeh

2013-05-01

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Xenogeneic transplantation of articular chondrocytes into full-thickness articular cartilage defects in minipigs: fate of cells and the role of macrophages.  

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Xenogeneic or allogeneic chondrocytes hold great potential to build up new cartilage in vivo. However, immune rejection is a major concern for the utility of universal donor-derived cells. In order to verify the reported immune privilege of chondrocytes in vivo, the aim of this study was to assess engraftment of human articular chondrocytes (HAC) in minipig knee cartilage defects and their contribution to cartilage regeneration. HAC were transplanted matrix-assisted within two hydrogels into full-thickness cartilage defects of minipigs or implanted ectopically into immune deficient mice to assess redifferentiation capacity. At 2 and 4 weeks after surgery, cell-persistence and host cell invasion were monitored by species-specific in situ hybridization and RT-PCR. Early tissue regeneration was evaluated by histomorphometry and a modified O'Driscoll score. HAC capable of successful in vivo chondrogenic redifferentiation persisted at ectopic sites for 4 weeks in both carrier materials. Early defect regeneration involved extensive host cell invasion and a decline of HAC to less than 5 % of initial cell numbers in 6/12 defects within 2 weeks. Few clusters of persisting HAC within collagen type II-rich tissue were surrounded by porcine macrophages. Four weeks after cell transplantation, most of the defects contained well-integrated cell-rich tissue free of human cells with no apparent difference between hydrogel carriers. In summary, HAC failed to engraft in porcine articular cartilage defects despite their ability for successful in vivo redifferentiation. The co-localization of macrophages to hydrogel-implanted HAC suggests active graft rejection without evidence for an immune-privileged status of xenogeneic chondrocytes in a large animal joint. PMID:25129109

Niemietz, Thomas; Zass, Gesa; Hagmann, Sébastien; Diederichs, Solvig; Gotterbarm, Tobias; Richter, Wiltrud

2014-12-01

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Evaluation of the repair of full-thickness articular cartilage defects filled with autologous exogenous fibrin clot: An experimental study in the shoulder joint of dogs  

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Full Text Available To determine whether the optimizing effect of an exogenous fibrin clot in the repair of full–thickness articular cartilage defects is valid when joint motions are restricted, standard osteochondral defects were constituted in the articular surface of the humeral head in 16 adult dogs. The defects in 8 dogs were packed with fibrin clots that had been prepared exogenously from each animal and the defects of the other animals were left empty. The operated limbs were inactivated for 2 weeks postoperatively and the healing response was then examined using routine histology at 2, 4, 8 and 12-week intervals. Although the clot-filled and control (empty defects initially healed through proliferation of fibrous connective tissue; the clot-filled defects finally modulated into fibrocartilage with completed subchondral bone formation. The clot-filled defects demonstrated a more advanced reparative tissue which was congruent with the intact articular surface from 4 weeks after the intervention.

Avki S.

2003-01-01

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Effect of tenascin-C on the repair of full-thickness osteochondral defects of articular cartilage in rabbits.  

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The purpose of this study was to examine the effect of tenascin-C (TNC) on the repair of full-thickness osteochondral defects of articular cartilage in vivo. We used a gellan-gellan-sulfate sponge (Gellan-GS) to maintain a TNC-rich environment in the cartilage defects. We implanted Gellan-GS soaked in PBS only (Group 1), Gellan-GS soaked in 10?µg/ml of TNC (Group 2), and Gellan-GS soaked in 100?µg/ml of TNC (Group 3) into a full-thickness osteochondral defect of the patellar groove of rabbits. The defect area was examined grossly and histologically 4-12 weeks after surgery. Sections of synovium were also immunohistochemically investigated. Histologically as well as macroscopically, the defects in Group 2 showed better repair than the other groups at 8 and 12 weeks after surgery. Inflammation of the synovium tended to diminish over time in all groups, and the degree of synovitis was the same for all three groups at each time point. In conclusion, Gellan-GS soaked in TNC can be used as a novel scaffold for the repair of articular cartilage defects. This study also indicates that TNC promotes the repair of full-thickness osteochondral defects in vivo. This article is protected by copyright. All rights reserved. PMID:25428773

Ikemura, Shigeto; Hasegawa, Masahiro; Iino, Takahiro; Miyamoto, Keiichi; Imanaka-Yoshida, Kyoko; Yoshida, Toshimichi; Sudo, Akihiro

2014-11-26

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Computational biomechanics of articular cartilage of human knee joint: effect of osteochondral defects.  

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Articular cartilage and its supporting bone functional conditions are tightly coupled as injuries of either adversely affects joint mechanical environment. The objective of this study was set to quantitatively investigate the extent of alterations in the mechanical environment of cartilage and knee joint in presence of commonly observed osteochondral defects. An existing validated finite element model of a knee joint was used to construct a refined model of the tibial lateral compartment including proximal tibial bony structures. The response was computed under compression forces up to 2000 N while simulating localized bone damage, cartilage-bone horizontal split, bone overgrowth and absence of deep vertical collagen fibrils. Localized tibial bone damage increased overall joint compliance and substantially altered pattern and magnitude of contact pressures and cartilage strains in both tibia and femur. These alterations were further exacerbated when bone damage was combined with base cartilage split and absence of deep vertical collagen fibrils. Local bone boss markedly changed contact pressures and strain patterns in neighbouring cartilage. Bone bruise/fracture and overgrowth adversely perturbed the homeostatic balance in the mechanical environment of articulate cartilage surrounding and opposing the lesion as well as the joint compliance. As such, they potentially contribute to the initiation and development of post-traumatic osteoarthritis. PMID:19660759

Shirazi, R; Shirazi-Adl, A

2009-11-13

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Gel-type autologous chondrocyte (Chondron™ implantation for treatment of articular cartilage defects of the knee  

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Full Text Available Abstract Background Gel-type autologous chondrocyte (Chondron™ implantations have been used for several years without using periosteum or membrane. This study involves evaluations of the clinical results of Chondron™ at many clinical centers at various time points during the postoperative patient follow-up. Methods Data from 98 patients with articular cartilage injury of the knee joint and who underwent Chondron™ implantation at ten Korean hospitals between January 2005 and November 2008, were included and were divided into two groups based on the patient follow-up period, i.e. 13~24-month follow-up and greater than 25-month follow-up. The telephone Knee Society Score obtained during telephone interviews with patients, was used as the evaluation tool. Results On the tKSS-A (telephone Knee Society Score-A, the score improved from 43.52 ± 20.20 to 89.71 ± 13.69 (P Conclusion Gel-type autologous chondrocyte implantation for chondral knee defects appears to be a safe and effective method for both decreasing pain and improving knee function.

Chun Chung-Woo

2010-05-01

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Autologous chondrocyte transplantation for the treatment of articular cartilage defects in the knee joint. Techniques and results  

International Nuclear Information System (INIS)

Currently the use of autologous chondrocytes as a cartilage-repair procedure for the repair of injured articular cartilage of the knee joint, is recommended. This review presents the technique of autologous chondrocyte transplantation (ACT) and their modifications as matrix-associated autologous chondrocyte transplantation (MACT). Beside the surgical procedure the experimental and clinical results are discussed. Furthermore the major complications and the indication guidelines are presented. Articular cartilage in adults has a poor ability to self-repair after a substantial injury. Surgical therapeutic efforts in treating cartilage defects have focused on bringing new cells capable of chondrogenesis into the lesions. With ACT good to excellent clinical results are seen in isolated posttraumatic lesions of the knee joint in the younger patient with the formation of hyalinelike repair tissue. The major complications are periosteal hypertrophy, delamination of the transplant, arthrofibrosis and transplant failure. The current limitations include osteoarthritic defects and higher patient age. With the right indication and operative technique ACT is an effective and save option for the treatment of large full thickness cartilage defect of the knee joint. (orig.)

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Late pulmonary scintigraphic defects after uneventful recovery from simple focal pneumonia of childhood.  

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We present a pilot study designed to determine whether pneumonia in children accompanied by focal consolidation on the chest radiograph (CXR) is associated with late abnormality as detected by radionuclide lung scintigraphy. 14 children with focal pneumonia were assessed 1 year after initial presentation. In 12 both krypton-81m ventilation and technetium-99m MAA perfusion studies were performed, while in two only perfusion studies were obtained. All cases had a further CXR. Abnormal or equivocal cases were reviewed clinically. Scans and CXRs were independently assessed by two observers and subsequently consensus reached by discussion. There were five abnormal and nine normal lung scans. Two defects matched the site of the initial pneumonia while three did not. A CXR at the time of lung scanning was normal except for one case with a small focus of consolidation on the opposite side to the initial pneumonia but with a normal lung scan. Similarly, clinical assessment at the time of scanning was unremarkable, with no history of further respiratory episodes except in one child excluded from the study because of an interval diagnosis of asthma. This pilot study indicates that lung scan defects are common in the medium term after supposedly uncomplicated pneumonia in childhood. The cause of these defects remains uncertain. The correlation with the site of the initial radiological abnormality is variable, pointing to the need for further research in this area. The importance of independent blind interpretation is also highlighted. PMID:8281378

Kenney, I J; Lenney, W; Lutkin, J E; Gordon, I

1993-11-01

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Finite element simulations of a focal knee resurfacing implant applied to localized cartilage defects in a sheep model.  

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Articular resurfacing metal implants have recently been tested in animal models to treat full thickness localized articular cartilage defects, showing promising results. However, the mechanical behavior of cartilage surrounding the metal implant has not been studied yet as it is technically challenging to measure in vivo contact areas, pressures, stresses and deformations from the metal implant. Therefore, we implemented a detailed numerical finite element model by approximating one of the condyles of the sheep tibiofemoral joint and created a defect of specific size to accommodate the implant. Using this model, the mechanical behavior of the surrounding of metal implant was studied. The model showed that the metal implant plays a significant role in the force transmission. Two types of profiles were investigated for metal implant. An implant with a double-curved profile, i.e., a profile fully congruent with the articular surfaces in the knee, gives lower contact pressures and stresses at the rim of the defect than the implant with unicurved spherical profile. The implant should be placed at a certain distance into the cartilage to avoid damage to opposing biological surface. Too deep positions, however, lead to high shear stresses in the cartilage edges around the implant. Mechanical sealing was achieved with a wedge shape of the implant, also useful for biochemical sealing of cartilage edges at the defect. PMID:21300358

Manda, Krishnagoud; Ryd, Leif; Eriksson, Anders

2011-03-15

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ICRS Recommendation Document : Patient-Reported Outcome Instruments for Use in Patients with Articular Cartilage Defects  

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Abstract Objective: The purpose of this article is to describe and recommend patient-reported outcome instruments for use in patients with articular cartilage lesions undergoing cartilage repair interventions. Methods: Nonsystematic literature search identifying measures addressing pain and function evaluated for validity and psychometric properties in patients with articular cartilage lesions. Results: The knee-specific instruments, titled the International Knee Documentation Committee Subjective Knee Form and the Knee injury and Osteoarthritis and Outcome Score, both fulfill the basic requirements for reliability, validity, and responsiveness in cartilage repair patients. A major difference between them is that the former results in a single score and the latter results in 5 subscores. A single score is preferred for simplicity’s sake, whereas subscores allow for evaluation of separate constructs at all levels according to the International Classification of Functioning. Conclusions: Because there is no obvious superiority of either instrument at this time, both outcome measures are recommended for use in cartilage repair. Rescaling of the Lysholm Scoring Scale has been suggested, and confirmatory longitudinal studies are needed prior to recommending this scale for use in cartilage repair. Inclusion of a generic measure is feasible in cartilage repair studies and allows analysis of health-related quality of life and health economic outcomes. The Marx or Tegner Activity Rating Scales are feasible and have been evaluated in patients with knee injuries. However, activity measures require age and sex adjustment, and data are lacking in people with cartilage repair.

Roos, Ewa M.; Engelhart, Luella

2011-01-01

 
 
 
 
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Pulsed electromagnetic field therapy results in healing of full thickness articular cartilage defect  

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This study aimed to determine the efficacy of PEMF (pulsed electromagnetic field) treatment in experimental osteochondral defect healing in a rabbit model. The study was conducted on 12 New Zealand white rabbits. Six rabbits formed the study group and six rabbits the control group. The right knee joints of all 12 animals were exposed and a 3.5-mm diameter osteochondral defect was created in the trochlear groove. The defect was filled with calcium phosphate scaffold. Six animals from the study...

Boopalan, P. R. J. V. C.; Arumugam, Sabareeswaran; Livingston, Abel; Mohanty, Mira; Chittaranjan, Samuel

2011-01-01

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Indium-111 chloride for detecting suspected hepatomas in patients with focal defects on technetium-99m sulfur colloid liver imaging  

International Nuclear Information System (INIS)

Twenty-three patients with hepatic cirrhosis and focal defects on Tc-99m sulfur colloid (SC) scintigrams were restudied with In-111 chloride to determine if indium localization in the focal defect is indicative of a hepatoma. Seven of eight patients with proven hepatomas had positive studies; however, six of 15 patients without hepatomas also had studies interpreted as positive. Thus, In-111 chloride is highly sensitive for the detection of hepatomas, and a negative indium study would militate against this diagnosis. The high false-positive rate found may be due to technical factors rather than a lack of specificity of localization; the experience of others seems to support this impression. At present, In-111 chloride scintigraphy for focal hepatic defects appears to be useful in ruling out hepatoma

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Repair of experimentally produced defects in rabbit articular cartilage by autologous chondrocyte transplantation  

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Using the knee joints of New Zealand White rabbits, a baseline study was made to determine the intrinsic capability of cartilage for healing defects that do not fracture the subchondral plate. A second experiment examined the effect of autologous chondrocytes grown in vitro on the healing rate of these defects. To determine whether any of the reconstituted cartilage resulted from the chondrocyte graft, a third experiment was conducted involving grafts with chondrocytes that had been labeled prior to grafting with a nuclear tracer. Results were evaluated using both qualitative and quantitative light microscopy. Macroscopic results from grafted specimens displayed a marked decrease in synovitis and other degenerative changes. In defects that had received transplants, a significant amount of cartilage was reconstituted (82%) compared to ungrafted controls (18%). Autoradiography on reconstituted cartilage showed that there were labeled cells incorporated into the repair matrix.

Grande, D.A.; Pitman, M.I.; Peterson, L.; Menche, D.; Klein, M.

1989-01-01

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Repair of experimentally produced defects in rabbit articular cartilage by autologous chondrocyte transplantation  

International Nuclear Information System (INIS)

Using the knee joints of New Zealand White rabbits, a baseline study was made to determine the intrinsic capability of cartilage for healing defects that do not fracture the subchondral plate. A second experiment examined the effect of autologous chondrocytes grown in vitro on the healing rate of these defects. To determine whether any of the reconstituted cartilage resulted from the chondrocyte graft, a third experiment was conducted involving grafts with chondrocytes that had been labeled prior to grafting with a nuclear tracer. Results were evaluated using both qualitative and quantitative light microscopy. Macroscopic results from grafted specimens displayed a marked decrease in synovitis and other degenerative changes. In defects that had received transplants, a significant amount of cartilage was reconstituted (82%) compared to ungrafted controls (18%). Autoradiography on reconstituted cartilage showed that there were labeled cells incorporated into the repair matrix

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Cultured articular chondrocytes sheets for partial thickness cartilage defects utilizing temperature-responsive culture dishes  

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Full Text Available The extracellular matrix (ECM of articular cartilage has several functions that are unique to joints. Although a technique for transplanting cultured chondrocytes has already been introduced, it is difficult to collect intact ECM when using enzymes to harvest samples. Temperature-responsive culture dishes have already been clinically applied in the fields of myocardial and corneal transplantation. Earlier studies have shown that a sheet of cultured cells with intact ECM and adhesive factors can be harvested using such culture dishes, which allow the surface properties of the dish to be reversibly altered by changing the temperature. Human chondrocytes were subjected to enzymatic digestion and then were seeded in temperature-responsive culture dishes. A sheet of chondrocytes was harvested by only reducing the temperature after the cultured cells reached confluency. A real-time PCR analysis of the chondrocyte sheets confirmed that type II collagen, aggrecan, and fibronectin were present. These results suggested that, although chondrocytes undergo dedifferentiation in a monolayer culture, multilayer chondrocyte sheets grown in a similar environment to that of three-dimensional culture may be able to maintain a normal phenotype. A histological examination suggested that multilayer chondrocyte sheets could thus prevent the loss of proteoglycans because the area covered by the sheets was well stained by safranin-O. The present experiments suggested that temperature-responsive culture dishes are useful for obtaining cultured chondrocytes, which may then be clinically employed as a substitute for periosteal patches because such sheets can be applied without a scaffold.

N Kaneshiro

2007-05-01

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Targeted Delivery of Extracellular Matrix Protected against Neurologic Defects after Focal Ischemia Reperfusion in Rats.  

Science.gov (United States)

Ischemic stroke is one of the leading causes of morbidity and mortality worldwide and characterized by defective angiogenesis. The functional sequences (RGDs, GRGDSPASSPISC) derived from fibronectin have been confirmed to augment angiogenesis in vivo and in vitro. However, delivery of peptides into the brain parenchyma has been hampered by the presence of the blood-brain barrier (BBB). We fused RGDs with penetratin (Antp) derived from Drosophila antennapedia homeodomain protein to improve the penetration of peptides through BBB into ischemic hemisphere. We found Antp-RGDs successfully not only penetrate the SH-SY5Y cells but also penetrated through BBB into ischemic hemisphere by intraperitoneal injection. In addition, application of Antp-RGDs to the focal cerebral ischemic reperfusion injury in rats resulted in the reduction of cerebral ischemic volume and the improvement of neurologic score according to the 21-point score. We further demonstrated that activation of phosphorylation-extracellular-signal related kinase 1/2 (p-ERK 1/2) and upregulation of gene VEGF resulted from post-treatment with Antp-RGDs 2 hours after reperfusion onset might at least partly contribute to the benefic changes after focal cerebral ischemic reperfusion injury in rats. Our data suggested that Antp-RGDs may serve as an attractive therapeutic intervention for treating ischemic stroke. PMID:25440330

Yang, HongNa; Yang, HongLing; Lu, YingYun; Ma, Shuang; Liu, Ying; Jia, GuoYong; Bi, JianZhong; Wang, CuiLan

2015-01-01

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Use of a Smooth, Resorbable Template for Delivery of Cultured Pellets of Autologous Chondrocytes to Articular Cartilage Defects—Preliminary Report  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background: Autologous chondrocyte transplantation (ACT) is the most commonly used cell-based surgical procedure for repair of articular cartilage defects. The challenges of this technique include dedifferentiation of chondrocytes following several in vitro passages, invasive means of transplantation, and inadequate cell retention leading to washout of transplanted cells. To overcome these obstacles, we developed a novel technique of transplanting high-density chondrocyte pellets seeded on a ...

Pomahac, Bohdan; Zuhaili, Baraa; Kudsi, Yusef; Aflaki, Pejman; Eriksson, Elof

2009-01-01

28

Articular cartilage defect detectability in human knees with MR-arthrography  

Energy Technology Data Exchange (ETDEWEB)

One hundred and thirteen knee joints were examined, of which 48 showed damage of the hyaline cartilage in one or more locations. For the evaluation of the magnetic resonance (MR) arthrographic images we used the macroscopic staging according to Outerbridge, the defect staging according to Bauer, as well as a new MR-arthrographic staging. The results of the evaluation were compared with the surgical findings in 61 knee joints. This revealed a sensitivity of 86 %, a specificity of 100 % and accuracy of 90 %. All lesions that could not be classified on MR-arthrography were of stage-I chondromalacia. (orig.)

Engel, A. [Orthopaedic Clinic, Univ. of Vienna (Austria); Kramer, J. [MR-Inst., Univ. of Vienna (Austria); Stiglbauer, R. [MR-Inst., Univ. of Vienna (Austria); Hajek, P.C. [MR-Inst., Univ. of Vienna (Austria); Imhof, H. [MR-Inst., Univ. of Vienna (Austria)

1993-04-01

29

Articular cartilage defect detectability in human knees with MR-arthrography  

International Nuclear Information System (INIS)

One hundred and thirteen knee joints were examined, of which 48 showed damage of the hyaline cartilage in one or more locations. For the evaluation of the magnetic resonance (MR) arthrographic images we used the macroscopic staging according to Outerbridge, the defect staging according to Bauer, as well as a new MR-arthrographic staging. The results of the evaluation were compared with the surgical findings in 61 knee joints. This revealed a sensitivity of 86 %, a specificity of 100 % and accuracy of 90 %. All lesions that could not be classified on MR-arthrography were of stage-I chondromalacia. (orig.)

30

Finite Element Simulations of Biphasic Articular Cartilages With Localized Metal Implants  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Articular cartilage is a specialized connective soft tissue that resides onthe ends of long-bones, transfers the load smoothly between the bones in diarthrodialjoints by providing almost frictionless, wear resistant sliding surfacesduring joint articulation. Focal chondral or osteochondral defects in articularcartilage are common and show limited capacity for biological repair. Furthermore,changes in the bio-mechanical forces at the defect site may makethe tissue more susceptible to continued...

Manda, Krishnagoud

2010-01-01

31

Repair of full-thickness articular cartilage defects by cultured mesenchymal stem cells transfected with the transforming growth factor ?1 gene  

International Nuclear Information System (INIS)

Articular cartilage repair remains a clinical and scientific challenge with increasing interest focused on the combined techniques of gene transfer and tissue engineering. Transforming growth factor beta 1 (TGF-?1) is a multifunctional molecule that plays a central role in promotion of cartilage repair, and inhibition of inflammatory and alloreactive immune response. Cell mediated gene therapy can allow a sustained expression of TGF-?1 that may circumvent difficulties associated with growth factor delivery. The objective of this study was to investigate whether TGF-?1 gene modified mesenchymal stem cells (MSCs) could enhance the repair of full-thickness articular cartilage defects in allogeneic rabbits. The pcDNA3-TGF-?1 gene transfected MSCs were seeded onto biodegradable poly-L-lysine coated polylactide (PLA) biomimetic scaffolds in vitro and allografted into full-thickness articular cartilage defects in 18 New Zealand rabbits. The pcDNA3 gene transfected MSCs/biomimetic scaffold composites and the cell-free scaffolds were taken as control groups I and II, respectively. The follow-up times were 2, 4, 12 and 24 weeks. Macroscopical, histological and ultrastructural studies were performed. In vitro SEM studies found that abundant cartilaginous matrices were generated and completely covered the interconnected pores of the scaffolds two weeks post-seeding in the experimental groups. In vivo, the qualixperimental groups. In vivo, the quality of regenerated tissue improved over time with hyaline cartilage filling the chondral region and a mixture of trabecular and compact bone filling the subchondral region at 24 weeks post-implantation. Joint repair in the experimental groups was better than that of either control group I or II, with respect to: (1) synthesis of hyaline cartilage specific extracellular matrix at the upper portion of the defect; (2) reconstitution of the subchondral bone at the lower portion of the defect and (3) inhibition of inflammatory and alloreactive immune responses. The transfected MSCs overexpressed their TGF-?1 gene products for at least 4 weeks in vivo. The control defects were filled with a mixture of fibrous and fibrocartilaginous tissue. The TGF-?1 gene transfected MSCs/poly-L-lysine coated PLA composite allografts used in this study are effective for articular cartilage repair. This novel TGF-?1 gene enhanced tissue engineering strategy may be of potential benefit to enhancing the repair of damaged articular cartilage, especially such damage caused by degenerative disease

32

The repair of full-thickness articular cartilage defects. Immune responses to reparative tissue formed by allogeneic growth plate chondrocyte implants  

International Nuclear Information System (INIS)

Growth plate cartilage cultivated in vitro was attached with a fibrin clot to a full-thickness articular cartilage defect on knee joints in allogeneic New Zealand rabbits. The healing of the defects was assessed by gross examination, light microscopy, and immunologic analysis for 24 weeks. Immunologic assessment of cell-mediated immunity, cytotoxicity of a humoral antibody by a 51 chromium release assay, and immunofluorescence studies were carried out. During the first two weeks following grafting, healing was excellent in 11 of the 17 defects. From three to 24 weeks, 11 of 42 defects examined had good results. Host lymphocytes had accumulated around the allograft at two to 12 weeks. Most of the implanted cartilage grown in vitro died and was replaced by fibrous tissue. The immunologic studies suggested that the implanted cartilage began to degenerate two to three weeks after implantation partially because of a humoral immune response but more importantly because of cell-mediated cytotoxicity

33

Hidrogéis de poliHEMA para reparo de defeitos da cartilagem articular: 1 - síntese e caracterização mecânica / PolyHEMA hydrogels for repairs or articular cartilage defects: 1 – systhesis and mechanical characterization  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Este trabalho visa a obtenção de hidrogéis de poli(2 hidróxi etil metacrilato) - poliHEMA com propriedades mecânicas adequadas ao uso dos mesmos no reparo de defeitos da cartilagem articular. Para tanto, duas alternativas foram estudadas: a variação da densidade de reticulação e a obtenção de blenda [...] s do tipo redes semi interpenetrantes (sIPN) de poliHEMA reticulado e diferentes polímeros como reforço. Amostras de hidrogéis foram obtidas por polimerização térmica e caracterizadas quanto à capacidade de absorção de água e de solução aquosa de NaCl 0,15 M e quanto ao comportamento mecânico, através de ensaios de fluência a indentação. Os resultados mostraram que a obtenção de blendas sIPN usando copolímero de MMA-AA como reforço é uma alternativa interessante para melhorar as propriedades mecânicas sem diminuir muito a capacidade de absorção de água dos hidrogéis. Abstract in english The purpose of this work was the study of poly-2-hydroxy-ethyl-metacrylate (polyHEMA) as a biomaterial for the repair of articular cartilage defects. Improvement of mechanical properties were studied by two distincts routes: changes in cross-link density of the gels and the synthesis of cellulose ac [...] etate and poly-methyl metacrylate-acrylic acid copolymers semi interpenetrating blends. The hydrogels were synthesized by thermal polymerization and characterized by swelling behaviour in 0.15 Mol.L-1 NaCl and by creep indentation tests. The results showed that the blending of PolyHEMA with poly-methyl metacrylate-acrylic acid copolymers significantly improved the mechanical properties of hydrogels without changes in their swelling behavior.

Sonia M, Malmonge; Cecília A. C, Zavaglia.

1997-06-01

34

Autologous chondrocyte transplantation for the treatment of articular cartilage defects in the knee joint. Techniques and results; Autologe Chondrozytentransplantation zur Behandlung von Knorpeldefekten des Kniegelenks. Techniken und Ergebnisse  

Energy Technology Data Exchange (ETDEWEB)

Currently the use of autologous chondrocytes as a cartilage-repair procedure for the repair of injured articular cartilage of the knee joint, is recommended. This review presents the technique of autologous chondrocyte transplantation (ACT) and their modifications as matrix-associated autologous chondrocyte transplantation (MACT). Beside the surgical procedure the experimental and clinical results are discussed. Furthermore the major complications and the indication guidelines are presented. Articular cartilage in adults has a poor ability to self-repair after a substantial injury. Surgical therapeutic efforts in treating cartilage defects have focused on bringing new cells capable of chondrogenesis into the lesions. With ACT good to excellent clinical results are seen in isolated posttraumatic lesions of the knee joint in the younger patient with the formation of hyalinelike repair tissue. The major complications are periosteal hypertrophy, delamination of the transplant, arthrofibrosis and transplant failure. The current limitations include osteoarthritic defects and higher patient age. With the right indication and operative technique ACT is an effective and save option for the treatment of large full thickness cartilage defect of the knee joint. (orig.) [German] Zur Behandlung umschriebener Defekte des artikulaeren Kniegelenkgelenkknorpels wird der Einsatz autologer Knorpelzellen zunehmend als neue biologische Methode empfohlen. Die Technik der autologen Chondrozytentransplantation (ACT) und deren Modifikationen als matrixassoziierte autologe Chondrozytentransplantation (MACT) werden dargestellt. Es erfolgt ein Ueberblick ueber die experimentellen und klinischen Ergebnisse mit der Darstellung der haeufigsten Komplikationen und den derzeit gueltigen Indikationsrichtlinien. Unter Verwendung qualitativ hochwertiger Zellen zeigen besonders posttraumatische Knorpeldefekte bei juengeren Patienten eine hohe Erfolgsquote mit der Ausbildung eines hyalinartigen Regeneratgewebes. Die haeufigsten Komplikationen der ACT sind Periosthypertrophie, Delamination des Transplantats, intraartikulaere Adhaesionen und Transplantatversagen. Die derzeit wichtigsten Limitierungen stellen die Osteoarthrose und ein hoeheres Patientenalter dar. Bei richtiger Indikationsstellung und operativer Technik kann die ACT als effiziente und sichere Therapieoption fuer die Behandlung grosser und tiefer Knorpeldefekte des Kniegelenks angesehen werden. (orig.)

Marlovits, S.; Kutscha-Lissberg, F.; Aldrian, S.; Resinger, C.; Singer, P.; Zeller, P.; Vecsei, V. [Universitaetsklinik fuer Unfallchirurgie, Medizinische Universitaet Wien (Austria)

2004-08-01

35

Defect density reduction in InAs/GaSb type II superlattice focal plane array infrared detectors  

Science.gov (United States)

InAs/GaSb short-period superlattices (SL) have proven their large potential for high performance focal plane array infrared detectors. Lots of interest is focused on the development of short-period InAs/GaSb SLs for mono- and bispectral infrared detectors between 3 - 30 ?m. InAs/GaSb short-period superlattices can be fabricated with up to 1000 periods in the intrinsic region without revealing diffusion limited behavior. This enables the fabrication of InAs/GaSb SL camera systems with very high responsivity, comparable to state of the art CdHgTe and InSb detectors. The material system is also well suited for the fabrication of dual-color mid-wavelength infrared InAs/GaSb SL camera systems. These systems exhibit high quantum efficiency and offer simultaneous and spatially coincident detection in both spectral channels. An essential point for the performance of two-dimensional focal plane infrared detectors in camera systems is the number of defective pixel on the matrix detector. Sources for pixel outages are manifold and might be caused by the dislocation in the substrate, the epitaxial growth process or by imperfections during the focal plane array fabrication process. The goal is to grow defect-free epitaxial layers on a dislocation free large area GaSb substrate. Permanent improvement of the substrate quality and the development of techniques to monitor the substrate quality are of particular importance. To examine the crystalline quality of 3" and 4" GaSb substrates, synchrotron white beam X-ray topography (SWBXRT) was employed. In a comparative defect study of different 3" GaSb and 4" GaSb substrates, a significant reduction of the dislocation density caused by improvements in bulk crystal growth has been obtained. Optical characterization techniques for defect characterization after MBE growth are employed to correlate epitaxially grown defects with the detector performance after hybridization with the read-out integrated circuit.

Walther, Martin; Rehm, Robert; Schmitz, Johannes; Niemasz, Jasmin; Rutz, Frank; Wörl, Andreas; Kirste, Lutz; Scheibner, Ralf; Wendler, Joachim; Ziegler, Johann

2011-01-01

36

Intra-articular administration of hyaluronic acid increases the volume of the hyaline cartilage regenerated in a large osteochondral defect by implantation of a double-network gel.  

Science.gov (United States)

Implantation of PAMPS/PDMAAm double-network (DN) gel can induce hyaline cartilage regeneration in the osteochondral defect. However, it is a problem that the volume of the regenerated cartilage tissue is gradually reduced at 12 weeks. This study investigated whether intra-articular administration of hyaluronic acid (HA) increases the volume of the cartilage regenerated with the DN gel at 12 weeks. A total of 48 rabbits were used in this study. A cylindrical osteochondral defect created in the bilateral femoral trochlea was treated with DN gel (Group DN) or left without any implantation (Group C). In both Groups, we injected 1.0 mL of HA in the left knee, and 1.0 mL of saline solution in the right knee. Quantitative histological evaluations were performed at 2, 4, and 12 weeks, and PCR analysis was performed at 2 and 4 weeks after surgery. In Group DN, the proteoglycan-rich area was significantly greater in the HA-injected knees than in the saline-injected knees at 12 weeks (P = 0.0247), and expression of type 2 collagen, aggrecan, and Sox9 mRNAs was significantly greater in the HA-injected knees than in the saline-injected knees at 2 weeks (P = 0.0475, P = 0.0257, P = 0.0222, respectively). The intra-articular administration of HA significantly enhanced these gene expression at 2 weeks and significantly increased the volume of the hyaline cartilage regenerated by implantation of a DN gel at 12 weeks. This information is important to develop an additional method to increase the volume of the hyaline cartilage tissue in a potential cartilage regeneration strategy using the DN gel. PMID:24394983

Fukui, Takaaki; Kitamura, Nobuto; Kurokawa, Takayuki; Yokota, Masashi; Kondo, Eiji; Gong, Jian Ping; Yasuda, Kazunori

2014-04-01

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Proteomic analysis profile of engineered articular cartilage with chondrogenic differentiated adipose tissue-derived stem cells loaded polyglycolic acid mesh for weight-bearing area defect repair.  

Science.gov (United States)

The present study was designed to investigate the possibility of full-thickness defects repair in porcine articular cartilage (AC) weight-bearing area using chondrogenic differentiated autologous adipose-derived stem cells (ASCs) with a follow-up of 3 and 6 months, which is successive to our previous study on nonweight-bearing area. The isolated ASCs were seeded onto the phosphoglycerate/polylactic acid (PGA/PLA) with chondrogenic induction in vitro for 2 weeks as the experimental group prior to implantation in porcine AC defects (8?mm in diameter, deep to subchondral bone), with PGA/PLA only as control. With follow-up time being 3 and 6 months, both neo-cartilages of postimplantation integrated well with the neighboring normal cartilage and subchondral bone histologically in experimental group, whereas only fibrous tissue in control group. Immunohistochemical and toluidine blue staining confirmed similar distribution of COL II and glycosaminoglycan in the regenerated cartilage to the native one. A vivid remolding process with repair time was also witnessed in the neo-cartilage as the compressive modulus significantly increased from 70% of the normal cartilage at 3 months to nearly 90% at 6 months, which is similar to our former research. Nevertheless, differences of the regenerated cartilages still could be detected from the native one. Meanwhile, the exact mechanism involved in chondrogenic differentiation from ASCs seeded on PGA/PLA is still unknown. Therefore, proteome is resorted leading to 43 proteins differentially identified from 20 chosen two-dimensional spots, which do help us further our research on some committed factors. In conclusion, the comparison via proteome provided a thorough understanding of mechanisms implicating ASC differentiation toward chondrocytes, which is further substantiated by the present study as a perfect supplement to the former one in nonweight-bearing area. PMID:24044689

Gong, Lunli; Zhou, Xiao; Wu, Yaohao; Zhang, Yun; Wang, Chen; Zhou, Heng; Guo, Fangfang; Cui, Lei

2014-02-01

38

Can technetium-99m-mercaptoacetyltriglycine replace technetium-99m-dimercaptosuccinic acid in the exclusion of a focal renal defect?  

Science.gov (United States)

The presence of focal renal damage dictates different management of a child with urinary tract infection (UTI) compared with children who have normal kidneys. Technetium-99m-dimercaptosuccinic (DMSA) has a high sensitivity in the detection of a focal defect, and allows estimation of differential function. The introduction of 99mTc-MAG3 with high renal extraction suggests that this may be useful in children with UTI but its role remains speculative. Fifty-nine children with previous UTI underwent both 99mTc-DMSA and MAG3 within 4 wk of each other. Differential function and assessment of the images were undertaken. There is close correlation (R2 = 0.97) between the differential function. Analysis of the 99mTc-DMSA and functional MAG3 images showed that the functional image had a specificity of 88% and a sensitivity of 88% in the detection of a focal parenchymal defect. Technetium-99m-MAG3 in the clinical setting of a child with UTl allows accurate assessment of differential function and a high probability of detecting a focal renal abnormality. PMID:1334134

Gordon, I; Anderson, P J; Lythgoe, M F; Orton, M

1992-12-01

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Plasma rico em plaquetas no tratamento de lesões condrais articulares induzidas experimentalmente em equinos: avaliação clínica, macroscópica, histológica e histoquímica / Platelet-rich plasma in the treatment of articular chondral defects experimentally induced in horses: clinical, macroscopic, histopathological and histochemical evaluation  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Estudou-se a eficácia do plasma rico em plaquetas (PRP) no tratamento de lesões condrais articulares, experimentalmente induzidas em equinos. Para isso, foi induzida uma lesão condral, na tróclea medial femoral dos dois membros pélvicos de quatro animais. Após 30 dias da indução, as oito articulaçõe [...] s foram divididas em dois grupos. Os animais do grupo 1 receberam o tratamento intralesional e intra-articular com PRP, e os do grupo 2 foram tratados apenas com solução fisiológica. As avaliações clínicas, constituídas de exames de claudicação e análises do líquido sinovial, foram realizadas antes da indução da lesão - tempo zero -, quinzenalmente, até 120 dias e aos 150 dias. Avaliações macroscópicas, histológicas e histoquímicas foram realizadas no tempo zero e aos 150 dias. Os equinos do grupo 1 apresentaram melhora do grau de claudicação em relação aos do grupo 2. Os exames macroscópicos, histológicos e histoquímicos revelaram melhor tecido de reparação igualmente no grupo 1. Concluiu-se que a administração de PRP apresentou efeitos benéficos no tratamento de lesões condrais experimentais de equinos. Abstract in english The use of platelet-rich plasma (PRP) in the treatment of articular cartilage defects induced experimentally in horses was studied. For this purpose, both patellofemoral joints of four animals were approached through arthroscopic surgery to perform a cartilage defect on the medial femoral trochlea. [...] After 30 days of induction the eight joints were divided into two groups. Group 1 animals received intralesional and intra-articular treatment with PRP and Group 2 animals were treated only with saline solution. The clinical assessments, constituted by lameness signs and synovial fluid analysis, were performed before induction of injury (time zero) and every 15 days in 120 days, with last analysis on day 150. The macroscopic and morphologic analysis were performed at 0 and 150 days. During the experiment Group 1 animals showed improvement in lameness when compared to Group 2 animals. The macroscopic and morphological analysis showed a better tissue repair in the treated horses. Thus, the implantation of autologous PRP showed beneficial effects in the treatment of chondral lesions, experimentally induced in horses.

A.L.M., Yamada; A.M., Carvalho; P.G.G., Oliveira; S.L., Felisbino; D.L., Queiroz; M.J., Watanabe; C.A., Hussni; A.L.G., Alves.

2012-04-01

40

Differentiation between grade 3 and grade 4 articular cartilage defects of the knee: Fat-suppressed proton density-weighted versus fat-suppressed three-dimensional gradient-echo MRI  

Energy Technology Data Exchange (ETDEWEB)

Background: Fat-suppressed (FS) proton density (PD)-weighted magnetic resonance imaging (MRI) and FS three-dimensional (3D) gradient-echo imaging such as spoiled gradient-recalled (SPGR) sequence have been established as accurate methods for detecting articular cartilage defects. Purpose: To retrospectively compare the diagnostic efficacy between FS PD-weighted and FS 3D gradient-echo MRI for differentiating between grade 3 and grade 4 cartilage defects of the knee with arthroscopy as the standard of reference. Material and Methods: Twenty-one patients who had grade 3 or 4 cartilage defects in medial femoral condyle at arthroscopy and knee MRI were included in this study: grade 3, >50% cartilage defects; grade 4, full thickness cartilage defects exposed to the bone. Sagittal FS PD-weighted MR images and FS 3D gradient-echo images with 1.5 T MR images were independently graded for the cartilage abnormalities of medial femoral condyle by two musculoskeletal radiologists. Statistical analysis was performed by Fisher's exact test. Inter-observer agreement in grading of cartilage was assessed using ? coefficients. Results: Arthroscopy revealed grade 3 defects in 17 patients and grade 4 defects in 4 patients in medial femoral condyles. For FS 3D gradient-echo images grade 3 defects were graded as grade 3 (n=15) and grade 4 (n=2), and all grade 4 defects (n=4) were correctly graded. However, for FS PD-weighted MR images all grade 3 defects were misinterpreted as grade 1 (n=1) and grade 4 (n=16), whereas all grade 4 defects (n=4) were correctly graded. FS 3D gradient-echo MRI could differentiate grade 3 from grade 4 defects (P=0.003), whereas FS PD-weighted imaging could not (P=1.0). Inter-observer agreement was substantial (?=0.70) for grading of cartilage using FS PD-weighted imaging, whereas it was moderate (?=0.46) using FS 3D gradient-echo imaging. Conclusion: FS 3D gradient-echo MRI is more helpful for differentiating between grade 3 and grade 4 cartilage defects than is FS PD-weighted imaging

Lee, So Yeon; Jee, Won-Hee; Kim, Sun Ki (Dept. of Radiology, Seoul St Mary' s Hospital, Catholic Univ. of Korea, Seoul (Korea)), e-mail: whjee@catholic.ac.kr; Koh, In-Jun (Dept. of Joint Reconstruction Center, Seoul National Univ. Bundang Hospital, Seoul (Korea)); Kim, Jung-Man (Dept. of Orthopedic Surgery, Seoul St Mary' s Hospital, Catholic Univ. of Korea, Seoul (Korea))

2010-05-15

 
 
 
 
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Differentiation between grade 3 and grade 4 articular cartilage defects of the knee: Fat-suppressed proton density-weighted versus fat-suppressed three-dimensional gradient-echo MRI  

International Nuclear Information System (INIS)

Background: Fat-suppressed (FS) proton density (PD)-weighted magnetic resonance imaging (MRI) and FS three-dimensional (3D) gradient-echo imaging such as spoiled gradient-recalled (SPGR) sequence have been established as accurate methods for detecting articular cartilage defects. Purpose: To retrospectively compare the diagnostic efficacy between FS PD-weighted and FS 3D gradient-echo MRI for differentiating between grade 3 and grade 4 cartilage defects of the knee with arthroscopy as the standard of reference. Material and Methods: Twenty-one patients who had grade 3 or 4 cartilage defects in medial femoral condyle at arthroscopy and knee MRI were included in this study: grade 3, >50% cartilage defects; grade 4, full thickness cartilage defects exposed to the bone. Sagittal FS PD-weighted MR images and FS 3D gradient-echo images with 1.5 T MR images were independently graded for the cartilage abnormalities of medial femoral condyle by two musculoskeletal radiologists. Statistical analysis was performed by Fisher's exact test. Inter-observer agreement in grading of cartilage was assessed using ? coefficients. Results: Arthroscopy revealed grade 3 defects in 17 patients and grade 4 defects in 4 patients in medial femoral condyles. For FS 3D gradient-echo images grade 3 defects were graded as grade 3 (n=15) and grade 4 (n=2), and all grade 4 defects (n=4) were correctly graded. However, for FS PD-weighted MR images all grade 3 defects were misinterpreted as grade 1 (n=1efects were misinterpreted as grade 1 (n=1) and grade 4 (n=16), whereas all grade 4 defects (n=4) were correctly graded. FS 3D gradient-echo MRI could differentiate grade 3 from grade 4 defects (P=0.003), whereas FS PD-weighted imaging could not (P=1.0). Inter-observer agreement was substantial (?=0.70) for grading of cartilage using FS PD-weighted imaging, whereas it was moderate (?=0.46) using FS 3D gradient-echo imaging. Conclusion: FS 3D gradient-echo MRI is more helpful for differentiating between grade 3 and grade 4 cartilage defects than is FS PD-weighted imaging

42

Biomechanical and histological evaluation of hydrogel implants in articular cartilage  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english We evaluated the mechanical behavior of the repaired surfaces of defective articular cartilage in the intercondylar region of the rat femur after a hydrogel graft implant. The results were compared to those for the adjacent normal articular cartilage and for control surfaces where the defects remain [...] ed empty. Hydrogel synthesized by blending poly(2-hydroxyethyl methacrylate) and poly(methyl methacrylate-co-acrylic acid) was implanted in male Wistar rats. The animals were divided into five groups with postoperative follow-up periods of 3, 5, 8, 12 and 16 weeks. Indentation tests were performed on the neoformed surfaces in the knee joint (with or without a hydrogel implant) and on adjacent articular cartilage in order to assess the mechanical properties of the newly formed surface. Kruskal-Wallis analysis indicated that the mechanical behavior of the neoformed surfaces was significantly different from that of normal cartilage. Histological analysis of the repaired defects showed that the hydrogel implant filled the defect with no signs of inflammation as it was well anchored to the surrounding tissues, resulting in a newly formed articular surface. In the case of empty control defects, osseous tissue grew inside the defects and fibrous tissue formed on the articular surface of the defects. The repaired surface of the hydrogel implant was more compliant than normal articular cartilage throughout the 16 weeks following the operation, whereas the fibrous tissue that formed postoperatively over the empty defect was stiffer than normal articular cartilage after 5 weeks. This stiffness started to decrease 16 weeks after the operation, probably due to tissue degeneration. Thus, from the biomechanical and histological point of view, the hydrogel implant improved the articular surface repair.

S.M., Malmonge; C.A.C., Zavaglia; W.D., Belangero.

2000-03-01

43

Cartilage from the edge of a debrided articular defect is inferior to that from a standard donor site when used for autologous chondrocyte cultivation.  

Science.gov (United States)

The aim of this study was to evaluate the cultivation potential of cartilage taken from the debrided edge of a chronic lesion of the articular surface. A total of 14 patients underwent arthroscopy of the knee for a chronic lesion on the femoral condyles or trochlea. In addition to the routine cartilage biopsy, a second biopsy of cartilage was taken from the edge of the lesion. The cells isolated from both sources underwent parallel cultivation as monolayer and three-dimensional (3D) alginate culture. The cell yield, viability, capacity for proliferation, morphology and the expressions of typical cartilage genes (collagen I, COL1; collagen II, COL2; aggrecan, AGR; and versican, VER) were assessed. The cartilage differentiation indices (COL2/COL1, AGR/VER) were calculated. The control biopsies revealed a higher mean cell yield (1346 cells/mg vs 341 cells/mg), but similar cell proliferation, viability and morphology compared with the cells from the edge of the lesion. The cartilage differentiation indices were superior in control cells: COL2/COL1 (threefold in biopsies (non-significant)); sixfold in monolayer cultures (p = 0.012), and 7.5-fold in hydrogels (non-significant), AGR/VER (sevenfold in biopsies (p = 0.04), threefold (p = 0.003) in primary cultures and 3.5-fold in hydrogels (non-significant)). Our results suggest that the cultivation of chondrocytes solely from the edges of the lesion cannot be recommended for use in autologous chondrocyte implantation. PMID:21357969

Malicev, E; Barli?, A; Kregar-Velikonja, N; Stražar, K; Drobni?, M

2011-03-01

44

Autogenous osteochondral ''plug'' transfer for the treatment of focal chondral defects: postoperative MR appearance with clinical correlation  

Energy Technology Data Exchange (ETDEWEB)

Objective: To describe the MR appearance following autogenous osteochondral ''plug'' transfer for the treatment of focal chondral defects of the knee. Design and patients: Twenty-nine 1.5-T MR knee studies including dynamic gadolinium enhancement were performed on 21 patients following autogenous osteochondral ''plug'' transfer. Three musculoskeletal radiologists retrospectively reviewed images to evaluate graft and donor site appearance and MR findings were correlated with clinical outcomes. Results: MR images demonstrated graft protuberance (n=12/21; range 1-2 mm), depression (n=2/21; range 1 mm), and surface incongruity: mild (n=17/21), moderate (n=2/21), marked (n=1/21). The T2 signal of graft cartilage was similar to that of adjacent cartilage in 25 of 29 examinations, and increased in four. Graft cartilage thickness relative to adjacent cartilage was <50% in six patients, 50-100% in 15. Graft enhancement in bone was absent at 2 weeks, but present at between 4 and 6 weeks following surgery. All patients had clinical follow-up examinations and knee outcome survey scores were obtained in 15 patients with follow-up greater than 3 months after surgery. All patients demonstrated the expected short-term progressive clinical improvement. Conclusion: MR images reveal a wide range of appearances following osteochondral ''plug'' transfer. Minor variations in graft orientation and surface congruity do not result in adverse clinical outcome in the short term. (orig.)

Sanders, T.G. [Dept. of Radiology, Univ. of Texas, San Antonio (United States); Dept. of Radiology, Wilford Hall Medical Center, Lackland AFB, Texas (United States); Dept. of Radiology, Lackland AFB, TX (United States); Mentzer, K.D. [Dept. of Orthopaedics, Wilford Hall USAF Medical Center, Lackland AFB, TX (United States); Miller, M.D. [Dept. of Orthopaedic Surgery, Univ. of Virginia, Charlottesville (United States); Morrison, W.B. [Thomas Jefferson Univ., Philadelphia, PA (United States). Dept. of Radiology; Campbell, S.E. [Dept. of Radiology, Wilford Hall USAF Medical Center, Lackland AFB, TX (United States); Penrod, B.J. [Musculoskeletal Radiology, Brooke Army Medical Center, San Antonio, TX (United States)

2001-10-01

45

Condrocalcinose articular familiar / Familial articular chondrocalcinosis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Condrocalcinose articular familiar é uma condição clínica caracterizada pela deposição de cristais de pirofosfato de cálcio no líquido sinovial e cartilagens articulares levando à artrite. Descrevemos três membros de uma família com condrocalcinose cujo quadro clínico era caracterizado por artrite i [...] ntermitente em dois e artrite crônica lembrando artrite reumatóide em um. A avaliação radiológica mostrou calcificações em cartilagens de diversas articulações, particularmente de joelhos. A utilização de colchicina foi suficiente para prevenir as crises de artrite em dois pacientes e o paciente com a forma crônica necessitou uso contínuo de antiinflamatórios não-hormonais. Embora aparentemente rara no Brasil, não afastamos a possibilidade desse dado estar subestimado e sugerimos que seja realizada uma avaliação radiológica articular dos familiares de todo paciente com diagnóstico de condrocalcinose esporádica. Abstract in english Familial articular chondrocalcinosis is a disorder characterized by deposition of calcium pyrophosphate dihydrate crystal in synovial fluid and articular cartilage that can cause joint pain and arthritis. We have identified three members of the same family with chondrocalcinosis. The clinical featur [...] es of the disease were intermittent episodes of arthritis in two patients and polyarthritis resembling rheumatoid arthritis in one member. The radiological evaluation showed calcification in several joints, particularly in cartilages of the knees. Therapy with colchicine was enough to prevent arthritic crisis in two patients and continous NSAID use was necessary to control symptoms in the last one. Familial chondrocalcinosis seems to be rare in Brazil, but we do not exclude the possibility that this figure is underestimated and suggest that in cases of sporadic chondrocalcinosis other members of the family should be fully investigated.

Mittermayer Barreto, Santiago; Liliana, Galrão; Isabella, Lima; Lucas, Prado; Melba, Moura.

2004-08-01

46

Tissue engineering for articular cartilage repair – the state of the art  

Directory of Open Access Journals (Sweden)

Full Text Available Articular cartilage exhibits little capacity for intrinsic repair, and thus even minor injuries or lesions may lead to progressive damage and osteoarthritic joint degeneration, resulting in significant pain and disability. While there have been numerous attempts to develop tissue-engineered grafts or patches to repair focal chondral and osteochondral defects, there remain significant challenges in the clinical application of cell-based therapies for cartilage repair. This paper reviews the current state of cartilage tissue engineering with respect to different cell sources and their potential genetic modification, biomaterial scaffolds and growth factors, as well as preclinical testing in various animal models. This is not intended as a systematic review, rather an opinion of where the field is moving in light of current literature. While significant advances have been made in recent years, the complexity of this problem suggests that a multidisciplinary approach – combining a clinical perspective with expertise in cell biology, biomechanics, biomaterials science and high-throughput analysis will likely be necessary to address the challenge of developing functional cartilage replacements. With this approach we are more likely to realise the clinical goal of treating both focal defects and even large-scale osteoarthritic degenerative changes in the joint.

B Johnstone

2013-05-01

47

MRI evaluation of acute articular cartilage injury of knee  

International Nuclear Information System (INIS)

Objective: To study the MRI manifestation of acute articular cartilage injury of knee for evaluating the extension and degree of the injury and guiding treatment. Methods: MRI of 34 patients with acute articular cartilage injury of knee within one day to fifteen days confirmed by arthroscopy and arthrotomy was reviewed and analyzed, with emphasis on articular cartilage and subchondral lesion. And every manifestation on MRI and that of arthroscopy and operation was compared. Results: The articular cartilage injury was diagnosed on MRI in 29 of 34 cases. Cartilage signal changes were found only in 4. The changes of cartilage shape were variable. Thinning of focal cartilage was showed in 3, osteochondral impaction in 3, creases of cartilage in 3, disrupted cartilage with fissuring in 13, cracks cartilage in 2, and cracks cartilage with displaced fragment in 1. Bone bruise and occult fracture were found only on MRI. Conclusion: The assessment of MRI and arthroscopy in acute articular cartilage injury are consistent. Combined with arthroscopy, MRI can succeed in assessing the extension and degree of acute articular injury and allowing treatment planning

48

Current concepts of articular cartilage repair.  

Science.gov (United States)

Articular cartilage provides a vital function in the homeostasis of the joint environment. It possesses unique mechanical properties, allowing for the maintenance of almost frictionless motion over a lifetime. However, cartilage is vulnerable to traumatic injury and due to its poor vascularity and inability to access mesenchymal stem cells, unable to facilitate a satisfactory healing response. Untreated chondral defects are thus likely to predispose patients to the development of osteoarthritis. Reconstitution and repair of articular cartilage is dependent on the neosynthesis or implantation of cartilage matrix elements, a goal which can be achieved through a variety of surgical means. Commonly used repair techniques include marrow stimulation, structural osteo-articular autografts or chondrocyte implantation. Despite substantial differences in the complexity and technical application of each method, all are united in the endeavour to restore joint function and prevent joint degeneration. Anyone attempting to treat cartilage defects must possess a basic understanding of the physiology of cartilage growth, and relevant factors affecting cartilage healing and repair. Furthermore, knowledge of the biomechanics and kinematics of the knee are essential in order to appreciate the forces acting on joint surfaces and repair tissues. Although clinical success is dependent on appropriate patient selection, accurate clinical assessment, definition of root causes and application of the right choice of treatment modality, the ultimate outcome of any intervention remains heavily reliant on the surgeon's proficiency in the technical aspects of the chosen surgical procedure. PMID:22308614

Schindler, Oliver S

2011-12-01

49

Intra-articular calcergy and its arthropathic sequelae.  

Science.gov (United States)

Local calcergy is an ectopic calcification reaction (due to hydroxyapatite formation) induced in connective tissue sites by the application of dilute solutions of certain metallic salts (calcergens). The phenomenon is usually produced in the subcutaneous tissues of the experimental animal. The single intra-articular injection of lead acetate (PbAc) solution (a known calcergen) into the knee joint of the rat is followed by opacity of the synovial membrane and para-articular tissues with the aggregation of macrophages and multinucleated giant cells and the formation of some granulation tissue. This lesion ultimately resolves and there is no cartilaginous degeneration. Repeated intra-articular injections of PbAc produce pronounced changes in the synovium and para-articular tissues. There is extensive calcific deposition with exuberant macrophage and giant cell accumulation and fibroblastic proliferation. The proliferated synovial membrance becomes adherent to articular cartilage. There is thinning and fragmentation of the latter with focal loss and replacement by fibrous tissue. Therefore, in contrast to the effects of a single injection, repeated calcergenic stimulation of the knee joint is associated with a destructive arthropathy. PMID:6699751

McClure, J

1984-01-01

50

Extra-articular manifestations.  

Science.gov (United States)

Rheumatoid arthritis and spondyloarthritis, a concept which includes diseases like ankylosing spondylitis, psoriatic arthritis, and arthritis/spondylitis associated with inflammatory bowel disease, are both chronic inflammatory rheumatologic conditions. This article focuses on extra-articular manifestations, defined as diseases and symptoms not directly related to the locomotor system. The different manifestations are addressed per body system. Diagnostic and prognostic implications of these manifestations in daily practice are discussed. PMID:19822047

Mielants, H; Van den Bosch, F

2009-01-01

51

Talar articular facets (facies articulares talares) in human calcanei.  

Science.gov (United States)

The variations of the talar articular facets in 176 calcanei were studied and classified. Three types were considered: type A = calcanei with two articular facets for the talar head, with four subtypes; type B = calcanei with one articular facet for the talar head, and two subtypes, and type C = unique articular facies in the superior surface of the calcaneus for the talus. We found 53% (94 cases) type B calcanei and 46% (82 cases) type A calcanei. No calcanei of type C were seen. PMID:2718725

Forriol Campos, F; Gomez Pellico, L

1989-01-01

52

Familial collapsing focal segmental glomerulosclerosis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The majority of patients with non-HIV-related collapsing focal segmental glomerular sclerosis (FSGS) have idiopathic disease. Only a few genetic forms associated with rare syndromes have been described in families. Here we report two families with multiple members who have collapsing FSGS with no clear associated secondary etiology. Genetic analysis revealed a defect in the TRPC6 gene in one family, but excluded all known common inherited podocyte defects in the other family. The course and r...

Liakopoulos, V.; Huerta, A.; Cohen, S.; Pollak, M. R.; Sirota, R. A.; Superdock, K.; Appel, G. B.

2011-01-01

53

[Present status and perspective of articular cartilage regeneration].  

Science.gov (United States)

Because the capacity of articular cartilage for repair is limited, defects are a major clinical problem, and there is at present no satisfactory clinical technique to regenerate cartilage defects. Current clinical practice involves the bone stimulation technique, which breaks subchondral bone to facilitate cartilage repair from bone marrow derived cells and cytokines. This consists of multiple perforations, abrasions, and micro-fractures. However, with this procedure, cartilage defects are repaired with fibrocartilage, which is known to be biochemically and biomechanically different from normal hyaline cartilage and degeneration occurs in the reparative tissue. Autologous chondrocyte implantation (ACI) for repair of human articular cartilage was reported in 1994, and approved by the USA Food and Drug Association in 1997. This procedure has been performed for more than 20000 people all over the world, but its effectiveness is still controversial. Mosaic plasty was explored in the 1990s. Using this procedure, we can repair defects with hyaline cartilage, but the donor site morbidity is unsolved. To explore a new method for cartilage repair, we transplanted autologous culture-expanded bone marrow mesenchymal cells into articular cartilage defects. Clinical symptoms were improred but the repair cartilage was not hyaline cartilage. Further improvement is required. Many investigations have been made in the search for better means of repair, including gene transduction and the addition of growth factors during cell culture. In addition to bone marrow mesenchymal cells, synovial cells, adipocytes, muscle cells, etc. have been evaluated. PMID:17473529

Wakitani, Shigeyuki

2007-05-01

54

Articular Manifestations of Systemic Diseases  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Many systemic diseases present with articular manifestations. An understanding of the clinical, laboratory and radiological features of these diseases can lead to early diagnosis and appropriate therapy. This article describes the articular presentation and management of four generalized disorders: idiopathic hemachromatosis; sarcoidosis; hepatitis-B virus-induced arthritis, and polymyositis-dermatomyositis induced arthritis.

Bensen, W. G.

1983-01-01

55

Tensorial Electrokinetics in Articular Cartilage  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Electrokinetic phenomena contribute to biomechanical functions of articular cartilage and underlie promising methods for early detection of osteoarthritic lesions. Although some transport properties, such as hydraulic permeability, are known to become anisotropic with compression, the direction-dependence of cartilage electrokinetic properties remains unknown. Electroosmosis experiments were therefore performed on adult bovine articular cartilage samples, whereby fluid flows were driven by el...

Reynaud, Boris; Quinn, Thomas M.

2006-01-01

56

Focal femoral condyle resurfacing.  

LENUS (Irish Health Repository)

Focal femoral inlay resurfacing has been developed for the treatment of full-thickness chondral defects of the knee. This technique involves implanting a defect-sized metallic or ceramic cap that is anchored to the subchondral bone through a screw or pin. The use of these experimental caps has been advocated in middle-aged patients who have failed non-operative methods or biological repair techniques and are deemed unsuitable for conventional arthroplasty because of their age. This paper outlines the implant design, surgical technique and biomechanical principles underlying their use. Outcomes following implantation in both animal and human studies are also reviewed. Cite this article: Bone Joint J 2013;95-B:301-4.

Brennan, S A

2013-03-01

57

Biologic approaches to articular cartilage surgery: future trends.  

Science.gov (United States)

The treatment of unicompartmental osteoarthritis and focal chondral pathologic conditions in the knee in active aging athletes has captured the interest of patients, clinicians, basic scientists, and medical industry researchers. Most would agree that a biologic solution to treating hyaline cartilage injuries and degeneration would be optimal over prosthetic joint arthroplasty. Articular cartilage resurfacing techniques and biologic surgical methods continue to evolve and have gained more acceptance in orthopedic practice. A consensus exists for the ultimate goal of achieving a more predictable and durable result after surgical tissue repair or regeneration. Numerous promising approaches are now on the horizon and although the final word is far from in, the integration of many of the anticipated advances in molecular medicine, biomedical engineering, polymer chemistry, cell biology, and clinical orthopedics contributes to an exciting and rapidly evolving field. This article reviews the current concepts of the biologic approach to articular cartilage pathologic conditions and discusses future trends and novel technologies. PMID:16164953

Sgaglione, Nicholas A

2005-10-01

58

Articular Cartilage Injuries  

Science.gov (United States)

... CARTILAGE DEFECT (INJURY) DIAGNOSED? The physician examines the knee, looking for decreased range of motion, pain along the joint line, swelling, fluid on the knee, abnormal alignment of the bones ...

59

Human telomerase reverse transcriptase and glucose-regulated protein 78 increase the life span of articular chondrocytes and their repair potential  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Like all mammalian cells, normal adult chondrocytes have a limited replicative life span, which decreases with age. To facilitate the therapeutic use of chondrocytes from older donors, a method is needed to prolong their life span. Methods We transfected chondrocytes with hTERT or GRP78 and cultured them in a 3-dimensional atelocollagen honeycomb-shaped scaffold with a membrane seal. Then, we measured the amount of nuclear DNA and glycosaminoglycans (GAGs and the expression level of type II collagen as markers of cell proliferation and extracellular matrix formation, respectively, in these cultures. In addition, we allografted this tissue-engineered cartilage into osteochondral defects in old rabbits to assess their repair activity in vivo. Results Our results showed different degrees of differentiation in terms of GAG content between chondrocytes from old and young rabbits. Chondrocytes that were cotransfected with hTERT and GRP78 showed higher cellular proliferation and expression of type II collagen than those of nontransfected chondrocytes, regardless of the age of the cartilage donor. In addition, the in vitro growth rates of hTERT- or GRP78-transfected chondrocytes were higher than those of nontransfected chondrocytes, regardless of donor age. In vivo, the tissue-engineered cartilage implants exhibited strong repairing activity, maintained a chondrocyte-specific phenotype, and produced extracellular matrix components. Conclusions Focal gene delivery to aged articular chondrocytes exhibited strong repairing activity and may be therapeutically useful for articular cartilage regeneration.

Sato Masato

2012-04-01

60

MR imaging of articular cartilage  

International Nuclear Information System (INIS)

MR imaging has evolved to the best non-invasive method for the evaluation of articular cartilage. MR imaging helps to understand the structure and physiology of cartilage, and to diagnose cartilage lesions. Numerous studies have shown high accuracy and reliability concerning detection of cartilage lesions and early changes in both structure and biochemistry. High contrast-to-noise ratio and high spatial resolution are essential for analysis of articular cartilage. Fat-suppressed 3D-T1 weighted gradient echo and T2-weighted fast spin echo sequences with or without fat suppression are recommended for clinical routine. In this article the anatomy and pathology of hyaline articular cartilage and the complex imaging characteristics of hyaline cartilage will be discussed. (orig.)

 
 
 
 
61

Intra-articular therapy in osteoarthritis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The medical literature was reviewed from 1968–2002 using Medline and the key words "intra-articular" and "osteoarthritis" to determine the various intra-articular therapies used in the treatment of osteoarthritis. Corticosteroids and hyaluronic acid are the most frequently used intra-articular therapies in osteoarthritis. Other intra-articular substances such as orgotein, radiation synovectomy, dextrose prolotherapy, silicone, saline lavage, saline injection without lavage, analgesic agents...

Uthman, I.; Raynauld, J.; Haraoui, B.

2003-01-01

62

Articular cartilage friction increases in hip joints after the removal of acetabular labrum.  

Science.gov (United States)

The acetabular labrum is believed to have a sealing function. However, a torn labrum may not effectively prevent joint fluid from escaping a compressed joint, resulting in impaired lubrication. We aimed to understand the role of the acetabular labrum in maintaining a low friction environment in the hip joint. We did this by measuring the resistance to rotation (RTR) of the hip, which reflects the friction of the articular cartilage surface, following focal and complete labrectomy. Five cadaveric hips without evidence of osteoarthritis and impingement were tested. We measured resistance to rotation of the hip joint during 0.5, 1, 2, and 3 times body weight (BW) cyclic loading in the intact hip, and after focal and complete labrectomy. Resistance to rotation, which reflects articular cartilage friction in an intact hip was significantly increased following focal labrectomy at 1-3 BW loading, and following complete labrectomy at all load levels. The acetabular labrum appears to maintain a low friction environment, possibly by sealing the joint from fluid exudation. Even focal labrectomy may result in increased joint friction, a condition that may be detrimental to articular cartilage and lead to osteoarthritis. PMID:22176711

Song, Yongnam; Ito, Hiroshi; Kourtis, Lampros; Safran, Marc R; Carter, Dennis R; Giori, Nicholas J

2012-02-01

63

Combined nanoindentation testing and scanning electron microscopy of bone and articular calcified cartilage in an equine fracture predilection site  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Condylar fracture of the third metacarpal bone (Mc3) is the commonest cause of racetrack fatality in Thoroughbred horses. Linear defects involving hyaline articular cartilage, articular calcified cartilage (ACC) and subchondral bone (SCB) have been associated with the fracture initiation site, which lies in the sagittal grooves of the Mc3 condyle. We discovered areas of thickened and abnormally-mineralised ACC in the sagittal grooves of several normal 18-month-old horses, at the same site tha...

Doube, M.; Ec, Firth; Boyde, A.; Aj, Bushby

2010-01-01

64

Fisiología del condrocito articular Physiology of articular cartilage  

Digital Repository Infrastructure Vision for European Research (DRIVER)

El condrocito es la única célula presente en el cartílago articular, por lo que es de gran importancia el conocimiento de los mecanismos que regulan sus funciones, en particular los mecanismos de transporte de membrana que le permiten a esta célula enfrentar los continuos cambios de la osmolaridad externa a que están sometidos como consecuencia de las variaciones en la carga mecánica. Los mecanismos implicados en la regulaciín del volumen intracelular, el pH in...

Julio César Sánchez Naranjo

2008-01-01

65

Focal segmental glomerulosclerosis  

Science.gov (United States)

Segmental glomerulosclerosis; Focal sclerosis with hyalinosis ... The cause of focal segmental glomerulosclerosis is often unknown. The condition affects both children and adults. It occurs slightly more often in men and boys. ...

66

Implante de condrócitos homólogos em defeitos osteocondrais de cães: padronização da técnica e avaliação histopatológica / Homologous articular chondrocytes implantation in osteochondral defects of dogs: technique and histopathological evaluation standardization  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Padronizou-se a metodologia para cultura de condrócitos em cães e avaliou-se seu implante em lesões osteocondrais, utilizando-se a membrana biossintética de celulose (MBC) como revestimento. Dez cães, adultos e clinicamente sadios, foram submetidos à artrotomia das articulações fêmoro-tíbio-patelare [...] s. Defeitos de 4mm de diâmetro e profundidade foram induzidos no sulco troclear de ambos os membros. MBC foi aplicada na base e na superfície das lesões. Os defeitos do membro direito foram preenchidos com condrócitos homólogos cultivados formando o grupo-tratado (GT); os do membro esquerdo, sem implante celular, foram designados grupo-controle (GC). A evolução pós-operatória foi analisada com especial interesse nos processos de reparação da lesão, por meio de histomorfometria e imuno-histoquímica para colágeno tipo II e sulfato de condroitina. A cultura de condrócitos homólogos apresentou alta densidade e taxa de viabilidade. Observou-se integridade do tecido neoformado com a cartilagem adjacente na avaliação histológica, em ambos os grupos. Na imuno-histoquímica, verificou-se predomínio de colágeno tipo II no GT. Morfometricamente, não houve diferença significativa entre o tecido fibroso e o fibrocartilaginoso entre os grupos. A cultura de condrócitos homólogos de cães foi exequível. O tecido neoformado apresentou qualidade discretamente superior associado ao implante homólogo de condrócitos, contudo não promoveu reparação por cartilagem hialina. Abstract in english The aim of the study is to standardize the methodology to achieve canine chondrocytes culture, and evaluate its implant on osteochondral defects made in the femoral trochlear sulcus of dogs, using the cellulose biosynthetic membrane (CBM) as coating. Ten healthy adult dogs without locomotor disorder [...] s were used. All animals were submitted to arthrotomy of stifle joints and defects of four millimeters in diameter x four millimeters deep were done in the femoral trochlear sulcus of both limbs. CBM were applied in the lesion base and surface of all limbs. In the treated group (TG), defects of the right limb were filled with cultivated homologous chondrocytes, and in control group (CG), defects of the left limb were left without cellular implant. Postoperative follow up was done by histomorphometry and Collagen type II and anti-chondroitin sulfate immunohistochemistry. The homologous chondrocytes culture showed high density and viability rate. Upon immunohistochemistry the predominance of type II collagen in extracellular matrix of TG was verified. However, no significant statistical difference was observed between the groups upon histomorphometry analysis of fibrous and fibrocartilaginous tissues. Canine homologous chondrocytes culture was practicable. Neoformed tissue showed slightly higher quality in TG, but without promoting repair by the hyaline cartilage.

L.S., Iamaguti; C.V.S., Brandão; L.S.L.S., Mota; J.J.T., Ranzani; L.M., Ribeiro; V.J.V., Rossetto; C.R., Padovani; S.L., Felisbino.

2013-02-01

67

Implante de condrócitos homólogos em defeitos osteocondrais de cães: padronização da técnica e avaliação histopatológica Homologous articular chondrocytes implantation in osteochondral defects of dogs: technique and histopathological evaluation standardization  

Directory of Open Access Journals (Sweden)

Full Text Available Padronizou-se a metodologia para cultura de condrócitos em cães e avaliou-se seu implante em lesões osteocondrais, utilizando-se a membrana biossintética de celulose (MBC como revestimento. Dez cães, adultos e clinicamente sadios, foram submetidos à artrotomia das articulações fêmoro-tíbio-patelares. Defeitos de 4mm de diâmetro e profundidade foram induzidos no sulco troclear de ambos os membros. MBC foi aplicada na base e na superfície das lesões. Os defeitos do membro direito foram preenchidos com condrócitos homólogos cultivados formando o grupo-tratado (GT; os do membro esquerdo, sem implante celular, foram designados grupo-controle (GC. A evolução pós-operatória foi analisada com especial interesse nos processos de reparação da lesão, por meio de histomorfometria e imuno-histoquímica para colágeno tipo II e sulfato de condroitina. A cultura de condrócitos homólogos apresentou alta densidade e taxa de viabilidade. Observou-se integridade do tecido neoformado com a cartilagem adjacente na avaliação histológica, em ambos os grupos. Na imuno-histoquímica, verificou-se predomínio de colágeno tipo II no GT. Morfometricamente, não houve diferença significativa entre o tecido fibroso e o fibrocartilaginoso entre os grupos. A cultura de condrócitos homólogos de cães foi exequível. O tecido neoformado apresentou qualidade discretamente superior associado ao implante homólogo de condrócitos, contudo não promoveu reparação por cartilagem hialina.The aim of the study is to standardize the methodology to achieve canine chondrocytes culture, and evaluate its implant on osteochondral defects made in the femoral trochlear sulcus of dogs, using the cellulose biosynthetic membrane (CBM as coating. Ten healthy adult dogs without locomotor disorders were used. All animals were submitted to arthrotomy of stifle joints and defects of four millimeters in diameter x four millimeters deep were done in the femoral trochlear sulcus of both limbs. CBM were applied in the lesion base and surface of all limbs. In the treated group (TG, defects of the right limb were filled with cultivated homologous chondrocytes, and in control group (CG, defects of the left limb were left without cellular implant. Postoperative follow up was done by histomorphometry and Collagen type II and anti-chondroitin sulfate immunohistochemistry. The homologous chondrocytes culture showed high density and viability rate. Upon immunohistochemistry the predominance of type II collagen in extracellular matrix of TG was verified. However, no significant statistical difference was observed between the groups upon histomorphometry analysis of fibrous and fibrocartilaginous tissues. Canine homologous chondrocytes culture was practicable. Neoformed tissue showed slightly higher quality in TG, but without promoting repair by the hyaline cartilage.

L.S. Iamaguti

2013-02-01

68

Impact characteristics of articular cartilage.  

Science.gov (United States)

A rigid l m high stainless steel drop tower employing linear bearings has been used to study the impact characteristics of human articular cartilage. Instrumentation included a specially designed optoelctronic position transducer, piezoelectric force transducer, and high speed storage oscilloscope. Forty-eight 9 mm diameter samples of living articular cartilage and subchondral bone from the tibial plateaus of 4 human donors have been impacted at strains from 10 to 50%, and strain rates of 500s-1 and 1000 s-1. The integral bone/cartilage samples were mounted in polymethyl methacrylate for testing. Bone and cement impact characteristics have been studied separately. Stress, strain, and energy absorption data have been assembled for all the samples. Chondrocyte viability subsequent to impact has been investigated with the use of tritum labeled proline and autoradiography. Viability has been studied in relation to both the mechanical data and structural damage. PMID:700994

Finlay, J B; Repo, R U

1978-01-01

69

Articular chondrocalcinosis in Saudi Arabia.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

OBJECTIVES To investigate the prevalence of articular chondrocalcinosis in subjects aged 50 years and above in a radiographic survey through 14 primary care clinics in North Riyadh, Kingdom of Saudi Arabia. METHODS Over a period of 7 months extending from September 1998 to March 1999, 153 patients attending 14 primary care clinics in North Riyadh, Kingdom of Saudi Arabia, were interviewed, examined and then requested to have radiographs...

Al-arfaj, Abdulrahman S.; Al-boukai, Ahmed A.

2002-01-01

70

Intra-articular chondroma of the knee  

Energy Technology Data Exchange (ETDEWEB)

Chondromas are tumours that develop in relation to the periosteum and, although they are common around the knee, most reports deal with soft tissue chondromas in para-articular locations or intracortical tumours in extra-articular regions. We report a rare case of an intra-articular chondroma in a 16-year-old boy of Asian origin developing in the region of the medial femoral condyle of the femur and extending into the femoral sulcus and the patellofemoral joint. (orig.)

Talwalkar, S.C.; Kambhampati, S.B.S.; Lang Stevenson, A.I. [Oldchurch Hospital, Romford, Essex (United Kingdom); Whitehouse, R. [Manchester University, Department of Radiology, Manchester (United Kingdom); Freemont, A. [University of Manchester, Department of Osteoarticular Pathology, Manchester (United Kingdom)

2005-06-01

71

Síndromes epilépticos focales  

Directory of Open Access Journals (Sweden)

Full Text Available En el año 2001 el Grupo de Trabajo para la Clasificación y Terminología de la Liga Internacional contra la Epilepsia propuso un esquema diagnóstico para las personas con crisis epilépticas y epilepsia. El propósito del trabajo fue mostrar las características principales de algunos de los síndromes epilépticos focales propuestos para ser incluidos dentro de este esquema diagnóstico, el cual ha sido concebido de una forma flexible que permitirá en un futuro la inclusión de otros síndromes epilépticos. Según este nuevo esquema diagnóstico los síndromes epilépticos focales se dividen en síndromes epilépticos focales idiopáticos, síndromes epilépticos focales familiares, síndromes epilépticos focales sintomáticos o probablemente sintomáticos.In 2001, the Working Group for the Classification and Terminology of the International League Against Epilepsy proposed a diagnostic scheme for those persons with epileptic seizures or with epilepsy. The aim of this paper is to show the main characteristics of some of the focal epileptic syndromes proposed to be included in this diagnostic scheme, which has been designed in such a flexible way that will allow the inclusion of other epileptic syndromes in a future. According to this new diagnostic scheme, the focal epileptic syndromes are divided into family focal idiopathic syndromes, symptomatic focal epileptic syndromes and symptomatic or probably symptomatic focal epileptic syndromes.

Albia J. Pozo Alonso

2004-06-01

72

Síndromes epilépticos focales  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish En el año 2001 el Grupo de Trabajo para la Clasificación y Terminología de la Liga Internacional contra la Epilepsia propuso un esquema diagnóstico para las personas con crisis epilépticas y epilepsia. El propósito del trabajo fue mostrar las características principales de algunos de los síndromes e [...] pilépticos focales propuestos para ser incluidos dentro de este esquema diagnóstico, el cual ha sido concebido de una forma flexible que permitirá en un futuro la inclusión de otros síndromes epilépticos. Según este nuevo esquema diagnóstico los síndromes epilépticos focales se dividen en síndromes epilépticos focales idiopáticos, síndromes epilépticos focales familiares, síndromes epilépticos focales sintomáticos o probablemente sintomáticos. Abstract in english In 2001, the Working Group for the Classification and Terminology of the International League Against Epilepsy proposed a diagnostic scheme for those persons with epileptic seizures or with epilepsy. The aim of this paper is to show the main characteristics of some of the focal epileptic syndromes p [...] roposed to be included in this diagnostic scheme, which has been designed in such a flexible way that will allow the inclusion of other epileptic syndromes in a future. According to this new diagnostic scheme, the focal epileptic syndromes are divided into family focal idiopathic syndromes, symptomatic focal epileptic syndromes and symptomatic or probably symptomatic focal epileptic syndromes.

Albia J., Pozo Alonso; Desiderio, Pozo Lauzán.

2004-06-01

73

Magnetic resonance imaging of articular cartilage abnormalities of the far posterior femoral condyle of the knee  

International Nuclear Information System (INIS)

Background: Incidental articular cartilage lesions of the far posterior femoral condyle (FPFC) are commonly detected. Whether or not these cartilage lesions are symptomatic or clinically significant is unknown. Purpose: To characterize and assess prevalence of articular cartilage abnormalities of the FPFC and associated bone marrow edema (BME) and/or internal derangements through magnetic resonance (MR) images. Material and Methods: 654 knee MR examinations were reviewed retrospectively. Sagittal fast spin-echo proton density-weighted images with and without fat suppression were acquired with a 1.5T scanner, and were evaluated by two readers by consensus. The following factors were assessed: 1) the prevalence of cartilage abnormalities, 2) laterality, 3) the type of cartilage abnormalities, 4) cartilage abnormality grading, 5) associated BME, 6) complications such as meniscal injury and cruciate ligament injury, and 7) knee alignment (femorotibial angle [FTA]). Results: Articular cartilage abnormalities of the FPFC were demonstrated in 157 of the 654 patients (24%). Of these, 40 patients demonstrated medial and lateral FPFC cartilage abnormalities and were thus counted as 80 cases. Focal lateral FPFC abnormalities were demonstrated in 117 of 197 cases (59.4%), while diffuse lateral FPFC abnormalities were demonstrated in 24 of 197 cases (12.2%). Focal medial FPFC abnormalities were demonstrated in 23 of 197 cases (11.6%), while diffuse medial FPFC abnormalities were de diffuse medial FPFC abnormalities were demonstrated in 33 of 197 cases (16.8%). No statistically significant pattern of associated BME, FTA, or internal derangements including meniscal and cruciate ligament injury was demonstrated. Conclusion: Articular cartilage abnormalities of the FPFC are common and were demonstrated in 24% of patients or 30% of cases. Lateral FPFC abnormalities occur 2.5 times more frequently than medial FPFC abnormalities and were more frequently focal compared with medial cohorts. BME is associated in 36.5% of cases

74

Magnetic resonance imaging of articular cartilage abnormalities of the far posterior femoral condyle of the knee  

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Background: Incidental articular cartilage lesions of the far posterior femoral condyle (FPFC) are commonly detected. Whether or not these cartilage lesions are symptomatic or clinically significant is unknown. Purpose: To characterize and assess prevalence of articular cartilage abnormalities of the FPFC and associated bone marrow edema (BME) and/or internal derangements through magnetic resonance (MR) images. Material and Methods: 654 knee MR examinations were reviewed retrospectively. Sagittal fast spin-echo proton density-weighted images with and without fat suppression were acquired with a 1.5T scanner, and were evaluated by two readers by consensus. The following factors were assessed: 1) the prevalence of cartilage abnormalities, 2) laterality, 3) the type of cartilage abnormalities, 4) cartilage abnormality grading, 5) associated BME, 6) complications such as meniscal injury and cruciate ligament injury, and 7) knee alignment (femorotibial angle [FTA]). Results: Articular cartilage abnormalities of the FPFC were demonstrated in 157 of the 654 patients (24%). Of these, 40 patients demonstrated medial and lateral FPFC cartilage abnormalities and were thus counted as 80 cases. Focal lateral FPFC abnormalities were demonstrated in 117 of 197 cases (59.4%), while diffuse lateral FPFC abnormalities were demonstrated in 24 of 197 cases (12.2%). Focal medial FPFC abnormalities were demonstrated in 23 of 197 cases (11.6%), while diffuse medial FPFC abnormalities were demonstrated in 33 of 197 cases (16.8%). No statistically significant pattern of associated BME, FTA, or internal derangements including meniscal and cruciate ligament injury was demonstrated. Conclusion: Articular cartilage abnormalities of the FPFC are common and were demonstrated in 24% of patients or 30% of cases. Lateral FPFC abnormalities occur 2.5 times more frequently than medial FPFC abnormalities and were more frequently focal compared with medial cohorts. BME is associated in 36.5% of cases

Ogino, Shuhei; Huang, Thomas; Watanabe, Atsuya; Iranpour-Boroujeni, Tannaz; Yoshioka, Hiroshi (Dept. of Radiology, Brigham and Women' s Hospital, Boston, MA (United States)), e-mail: hiroshi@uci.edu

2010-01-15

75

CT features and clinical significance of lumbar articular facet syndrome  

International Nuclear Information System (INIS)

Objective: To discuss the CT features and its clinical significance of lumbar articular facet syndrome. Methods: Based on CT findings and clinical data of lumbar articular facet, 51 cases with lumbar articular facet syndrome and 11 normal young adults were analyzed and compared retrospectively. Results: The CT findings of lumbar articular facet syndrome were: (1)hyperostosis and hypertrophy of articular process; (2)the narrowing space of inter-articular facet; (3)vacuum sign in articular facet; (4)coarse and osteosclerosis of articular facet; (5)partial dislocation of articular facet; (6)calcification in peri-articular facet; (7)complications including disc bulge, discprotrusion, vacuum sign in disc, hypertrophy and calcification of ligamentum flavum. Conclusion: CT features of lumbar articular facet syndrome are multifarious, which should be analyzed in all respects. . (authors)

76

FIFTH LUMBAR VERTEBRA ASSOCIATED WITH ABSENCE OF SPINOUS PROCESS, LAMINAE AND INFERIOR ARTICULAR PROCESSES. – CASE REPORT  

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Full Text Available Background: The vertebral disorders are the ones which lead to disability and lot of health problems. Since the lumbar part of the vertebral column is the main weight bearing and weight transmitting region, if there is a defective development, the area for muscle attachment and the strong bony structure for the transmission of weight would be missing leading to instability at an early age. In the present case dry and processed fifth lumbar vertebra, of unknown sex which presented the features with absence of spinous process, laminae and the inferior articular processes on both sides which were obtained for teaching the medical undergraduate students in M.S.Ramaiah Medical College, Bangalore. There was absence of spinous process, laminae and the inferior articular processes of fifth lumbar vertebra leading to a wide spina bifida with absence of laminae, inferior articular processes on both sides and spinous process of fifth lumbar vertebra which could be a developmental anomaly.

Prathap Kumar

2013-09-01

77

Extra-articular Manifestations in Rheumatoid Arthritis.  

Science.gov (United States)

Rheumatoid arthritis (RA) is a systemic autoimmune disease whose main characteristic is persistent joint inflammation that results in joint damage and loss of function.Although RA is more common in females, extra-articular manifestations of the disease are more common in males. The extra-articular manifestations of RA can occur at any age after onset. It is characterised by destructive polyarthritis and extra-articular organ involvement, including the skin, eye, heart, lung, renal, nervous and gastrointestinal systems. The frequence of extra-articular manifestations in RA differs from one country to another. Extra-articular organ involvement in RA is more frequently seen in patients with severe, active disease and is associated with increased mortality. Incidence and frequence figures for extra-articular RA vary according to study design. Extra-articular involvement is more likely in those who have RF and/or are HLA-DR4 positive. Occasionally, there are also systemic manifestations such as vasculitis, visceral nodules, Sjögren's syndrome, or pulmonary fibrosis present. Nodules are the most common extra-articular feature, and are present in up to 30%; many of the other classic features occur in 1% or less in normal clinic settings. Sjögren's syndrome, anaemia of chronic disease and pulmonary manifestations are relatively common - in 6-10%, are frequently present in early disease and are all related to worse outcomes measures of rheumatoid disease in particular functional impairment and mortality. The occurrence of these systemic manifestations is a major predictor of mortality in patients with RA.This paper focuses on extra-articular manifestations, defined as diseases and symptoms not directly related to the locomotor system. PMID:21977172

Cojocaru, Manole; Cojocaru, Inimioara Mihaela; Silosi, Isabela; Vrabie, Camelia Doina; Tanasescu, R

2010-12-01

78

MRI of articular cartilaginous lesions. MRI findings in osteoarthritis of the knee joint  

International Nuclear Information System (INIS)

An investigation was carried out to assess the usefulness of magnetic resonance imaging for imaging of the knee joint, especially for detecting articular cartilaginous lesions associated with osteoarthritis of the knee. A total of 141 patients with osteoarthritis were examined (23 males, 118 females). Their age range was 40-93 (mean age 66.2). Using radiotherapy examinations, patients were classified according to Hokkaido University Classification Criteria; 22, 49, 46, 16, and 8 patients were classified as Type I, II, III, IV and V, respectively. Articular cartilage defects were examined using MRI, and the number of such defects increased as the X-ray stage progressed. The appearance of a low signal intensity area in the bone marrow was examined using MRI, and the number of patients observed to have such areas increased as the x-ray stages progressed. JOA OA scores were significantly low for patients with meniscal tears. Patients were classified and results reviewed using MRI examinations. Classification by MRI of articular cartilage lesions correlated with the JOA OA scores. Low signal intensity areas in the bone marrow were frequently observed in advanced osteoarthritis cases, and there was correlation between FTA and MRI classifications of these areas. MRI is extremely valuable in detecting articular cartilage lesions in the knee joint, showing those lesions which cannot be detected by conventional radiography examinations. Thus, MRI is judged to be a clinically us Thus, MRI is judged to be a clinically useful method for diagnosis of osteoarthritis. (author)

79

A Novel Biomaterial for Cartilage Repair Generated by Self-Assembly: Creation of a Self-Organized Articular Cartilage-Like Tissue  

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Recently, attention has been drawn to tissue engineering and other novel techniques aimed at reconstruction of the joint. Regarding articular cartilage tissue engineering, three-dimensional materials created in vitro by cultivation of autologous chondrocytes or mesenchymal stem cells with a collagen gel have been implanted to replace defective parts of the articular cartilage in limited cases with the diseases such as trauma or arthritis. However, several passages of chondrocyte culture are r...

Rie Karasawa; Kazuo Yudoh

2012-01-01

80

[Extra-articular manifestations of rheumatoid polyarthritis].  

Science.gov (United States)

Rheumatoid arthritis is mainly a chronic and disabling articular disease. If most patients do well (because of limited form or efficient treatment), in some cases they present with extra-articular rheumatoid arthritis. The clinical manifestations of extra-articular rheumatoid arthritis are wide, ranging from common and benign manifestations such as rheumatoid nodules to severe events such as Felty's syndrome or systemic vasculitis. The incidence of systemic rheumatoid arthritis seems cumulative over the course of the chronic disease, and the severity of individuals lesions when fully developed can be of major importance and even life threatening. A classification of the main features of extra-articular rheumatoid arthritis is given (even if not perfect), and the clinical manifestations are described. PMID:9501618

De Bandt, M; Meyer, O

1997-11-15

 
 
 
 
81

Focal vibration in neurorehabilitation.  

Science.gov (United States)

During the last decade, many studies have been carried out to understand the effects of focal vibratory stimuli at various levels of the central nervous system and to study pathophysiological mechanisms of neurological disorders as well as the therapeutic effects of focal vibration in neurorehabilitation. This review aimed to describe the effects of focal vibratory stimuli in neurorehabilitation including the neurological diseases or disorders like stroke, spinal cord injury, multiple sclerosis, Parkinson's' disease and dystonia. In conclusion, focal vibration stimulation is well tolerated, effective and easy to use, and it could be used to reduce spasticity, to promote motor activity and motor learning within a functional activity, even in gait training, independent from etiology of neurological pathology. Further studies are needed in the future well-designed trials with bigger sample size to determine the most effective frequency, amplitude and duration of vibration application in the neurorehabilitation. PMID:24842220

Murillo, N; Valls-Sole, J; Vidal, J; Opisso, E; Medina, J; Kumru, H

2014-04-01

82

Articular cartilage repair and the evolving role of regenerative medicine  

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Full Text Available Pieter K Bos1, Marloes L van Melle1, Gerjo JVM van Osch1,21Department of Orthopaedic Surgery, Erasmus MC, Rotterdam, the Netherlands; 2Department of Otorhinolaryngology, Erasmus MC, Rotterdam, the NetherlandsAbstract: Among the growing applications of regenerative medicine, clinical articular cartilage repair has now been used for 2 decades and forms a successful example of translational medicine. Cartilage is characterized by a limited intrinsic repair capacity following injury. Articular cartilage defects cause symptoms, are not spontaneously repaired, and are generally believed to result in early osteoarthritis. Marrow stimulation techniques, osteochondral transplantation, and cell-based therapies, such as autologous chondrocyte implantation (ACI and use of mesenchymal stem cells (MSCs, are used for tissue regeneration, symptom relief, and prevention of further joint degeneration. The exact incidence of cartilage defects and the natural outcome of joints with these lesions are unclear. Currently available cartilage repair techniques are designed for defect treatment in otherwise healthy joints and limbs, mostly in young adults. The natural history studies presented in this review estimated that the prevalence of cartilage lesions in this patient group ranges from 5% to 11%. The background and results from currently available randomized clinical trials of the three mostly used cartilage repair techniques are outlined in this review. Osteochondral transplantation, marrow stimulation, and ACI show improvement of symptoms with an advantage for cell-based techniques, but only a suggestion that risk for joint degeneration can be reduced. MSCs, characterized by their good proliferative capacity and the potential to differentiate into different mesenchymal lineages, form an attractive alternative cell source for cartilage regeneration. Moreover, MSCs provide a regenerative microenvironment by the secretion of bioactive factors. This trophic activity is believed to limit damage and stimulate intrinsic regenerative responses. Finally, important clinical issues are discussed, including techniques to study the role of implanted cells in tissue regeneration using cell labeling and cell tracking, the improvement of cartilage integration, the use of delayed gadolinium-enhanced magnetic resonance imaging of cartilage for early judgment of joint degeneration/regeneration, and the influence of regulatory rules for therapeutic application development.Keywords: articular cartilage, repair, imaging, techniques

Pieter K Bos

2010-10-01

83

Focal nodular hyperplasia  

International Nuclear Information System (INIS)

Focal nodular hyperplasia was diagnosed angiographically in 14 patients and confirmed histologically. Differentiation of this benign lesion from other space-occupying diseases of the liver can be very difficult, since focal nodular hyperplasiy produces a variable angiographic appearance. The typical angiogramm showing radial vessels in the arterial phase and sharply demarkated foci in the parenchyma phase is found in only one third of patients. Angiographic differential diagnosis includes adenomas and carcinomas of the liver. Resection of the tumours in case of malignant tumours is not indicated. Foci at the margin of the liver, or if they are pedunculated, should be removed in case of spontaneous perforation. Tumours in the centre of the liver should be observed (computer tomography). Oral contraceptives stimulate the growth of these foci. They may diminish in size after stopping these drugs. 70% of cases of focal nodular hyperplasia remain clinically silent and were discovered accidentally or at autopsy. (orig.)

84

Avaliação microbiológica e molecular de líquidos articulares e peri-articulares de suínos / Microbiological and molecular evaluation of articulares and peri-articulares fluids of pigs  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese No presente estudo coletaram-se 115 amostras de líquido articular e peri-articular de suínos com suspeita clínica de doença articular oriundos de maternidade (30,43%), creche (44,35%) e crescimento/terminação (25,22%) de Sistemas Intensivos de Produção de Suínos (SIPs) para avaliação microbiológica [...] e molecular. Observaram-se 57 (49,5%) amostras positivas em pelo menos uma das técnicas. No isolamento microbiano, 39,13% das amostras foram positivas, sendo Streptococcus spp. (19,72%), Arcabobacterium pyogenes (18,13%) e Escherichia coli (12,68%) os mais frequentes, havendo também a presença de Candida sp. (2,6%). Na técnica de Reação em Cadeia da Polimerase (PCR), em 20% das amostras foram detectados microrganismos com uma maior ocorrência de Mycoplasma hyosinoviae (34,09%), Erysipelotrix tonsilarum (20,45%) e Haemophilus parasuis (15,90%). Os microrganismos mais frequentemente isolados em animais com artrite, apresentaram distribuição em todas as faixas etárias, entretanto a fase de crescimento/terminação apresentou maior percentual (69%) de amostras positivas. Streptococcus spp. ocorreu em todas as fases sendo o microrganismo mais detectado. M. hyosinoviae foi observado principalmente em animais de creche. Na fase de crescimento/terminação as bactérias predominantes foram A. pyogenes, H. parasuis e E. tonsilarum. Aproximadamente metade dos casos foi negativo o que indica a provável ocorrência de processos degenerativos como a osteocondrose, embora a participação de infecções articulares e peri-articulares possam representar grandes perdas com menor ou maior impacto dependendo da fase de criação. Problemas articulares e/ou peri-articulares de origem infecciosas foram encontrados em todas as propriedades estudadas. O principal agente foi M. hyosynoviae, principalmente na creche, porém não se pode descartar o envolvimento de problemas degenerativos em associação. Abstract in english In this study, 115 samples of articular and peri-articular liquid from swine with clinical suspected disease were collected from farrow (30.43%), nursery (44.35%) and growing-finishing (25.22%) phases of Intensive Pig Production Systems (IPPSs) for microbiological and molecular evaluation. A total o [...] f 57 (49.5%) samples was positive for at least one test. In bacterial isolation, 39.13% were positive, with highest frequency of Streptococcus spp. (19.72%), Arcanobacterium pyogenes (18.13%) and Escherichia coli (12.68%), and in some cases the fungus Candida sp. (2.6%). In the polymerase chain reaction test, 20% of the samples were positive mostly for Mycoplasma hyosinoviae (34.09%), Erysipelotrix tonsilarum (20.45%) and Haemophilus parasuis (15.90%). Almost all microorganisms were distributed over every growth phase, with a higher percentage of cases in the growing-finishing phase (69%). Streptococcus spp. were the principal microorganisms detected and were frequent in all phases. M. hyosinoviae was predomiant in the nursery phase. In the growing-finishing phase, A. pyogenes, H. parasuis and E. tonsilarum were predominant. About half of the cases were negative, what probably indicates degenerative processes like osteochondrosis; however articular and peri-articular infections still represent great economic losses with more or less impact depending on the growing phase of the pigs. Articular and peri-articular infectious problems were found in all herds analyzed. M. hyosinoviae mainly in nursery phase, however associated with degenerative processes, could not be excluded.

Ana Carolina S., Faria; João X. de, Oliveira Filho; Daphine A.J. de, Paula; Laila Natasha S., Brandão; Danny Franciele S., Dias; Luciano, Nakazato; Valéria, Dutra.

2011-08-01

85

Articular chondrocyte metabolism and osteoarthritis  

International Nuclear Information System (INIS)

The three main objectives of this study were: (1) to determine if depletion of proteoglycans from the cartilage matrix that occurs during osteoarthritis causes a measurable increase of cartilage proteoglycan components in the synovial fluid and sera, (2) to observe what effect intracellular cAMP has on the expression of matrix components by chondrocytes, and (3) to determine if freshly isolated chondrocytes contain detectable levels of mRNA for fibronectin. Canine serum keratan sulfate and hyaluronate were measured to determine if there was an elevation of these serum glycosaminoglycans in a canine model of osteoarthritis. A single intra-articular injection of chymopapain into a shoulder joint increased serum keratan sulfate 10 fold and hyaluronate less than 2 fold in 24 hours. Keratan sulfate concentrations in synovial fluids of dogs about one year old were unrelated to the presence of spontaneous cartilage degeneration in the joints. High keratan sulfate in synovial fluids correlated with higher keratan sulfate in serum. The mean keratan sulfate concentration in sera of older dogs with osteoarthritis was 37% higher than disease-free controls, but the difference between the groups was not statistically significant. Treatment of chondrocytes with 0.5 millimolar (mM) dibutyryl cAMP (DBcAMP) caused the cells to adopt a more rounded morphology. There was no difference between the amount of proteins synthesized by cultures treated with DBcAMP and controls. The amount of f with DBcAMP and controls. The amount of fibronectin (FN) in the media of DBcAMP treated cultures detected by an ELISA was specifically reduced, and the amount of 35S-FN purified by gelatin affinity chromatography decreased. Moreover, the percentage of FN containing the extra domain. A sequence was reduced. Concomitant with the decrease in FN there was an increase in the concentration of keratan sulfate

86

Reversible focal splenial lesions  

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Reversible focal lesions in the splenium of the corpus callosum (SCC) have recently been reported.They are circumscribed and located in the median aspect of the SCC. On MRI, they are hyperintense on T2-W and iso-hypointense on T1-W sequences, with no contrast enhancement. On DWI, SCC lesions are hyperintense with low ADC values, reflecting restricted diffusion due to cytotoxic edema. The common element is the disappearance of imaging abnormalities with time, including normalization of DWI. Clinical improvement is often reported. The most established and frequent causes of reversible focal lesions of the SCC are viral encephalitis, antiepileptic drug toxicity/withdrawal and hypoglycemic encephalopathy. Many other causes have been reported, including traumatic axonal injury. The similar clinical and imaging features suggest a common mechanism induced by different pathological events leading to the same results. Edema and diffusion restriction in focal reversible lesions of the SCC have been attributed to excitotoxic mechanisms that can result from different mechanisms; no unifying relationship has been found to explain all the pathologies associated with SCC lesions. In our opinion, the similar imaging, clinical and prognostic aspects of these lesions depend on a high vulnerability of the SCC to excitotoxic edema and are less dependent on the underlying pathology. In this review, the relevant literature concerning reversible focal lesions in the SCC is analyzed and hypotheses about their pathogenesis are proposed. (orig.)

Gallucci, Massimo; Limbucci, Nicola [University of L' Aquila, Department of Radiology, S. Salvatore Hospital, L' Aquila (Italy); Paonessa, Amalia [Loreto Nuovo Hospital, Department of Neuroradiology, Napoli (Italy); Caranci, Ferdinando [Federico II University, Department of Neurological Sciences, Napoli (Italy)

2007-07-15

87

Reversible focal splenial lesions  

International Nuclear Information System (INIS)

Reversible focal lesions in the splenium of the corpus callosum (SCC) have recently been reported.They are circumscribed and located in the median aspect of the SCC. On MRI, they are hyperintense on T2-W and iso-hypointense on T1-W sequences, with no contrast enhancement. On DWI, SCC lesions are hyperintense with low ADC values, reflecting restricted diffusion due to cytotoxic edema. The common element is the disappearance of imaging abnormalities with time, including normalization of DWI. Clinical improvement is often reported. The most established and frequent causes of reversible focal lesions of the SCC are viral encephalitis, antiepileptic drug toxicity/withdrawal and hypoglycemic encephalopathy. Many other causes have been reported, including traumatic axonal injury. The similar clinical and imaging features suggest a common mechanism induced by different pathological events leading to the same results. Edema and diffusion restriction in focal reversible lesions of the SCC have been attributed to excitotoxic mechanisms that can result from different mechanisms; no unifying relationship has been found to explain all the pathologies associated with SCC lesions. In our opinion, the similar imaging, clinical and prognostic aspects of these lesions depend on a high vulnerability of the SCC to excitotoxic edema and are less dependent on the underlying pathology. In this review, the relevant literature concerning reversible focal lesions in the SCC is analyzed and hypoal lesions in the SCC is analyzed and hypotheses about their pathogenesis are proposed. (orig.)

88

Focal nodular hyperplasia  

International Nuclear Information System (INIS)

Focal nodular hyperplasia is the second most common benign liver tumor after hemangioma and occurs predominantly in young women. Imaging techniques are crucial in the diagnosis of this lesion. In this article, we will present the imaging findings of the classic and non-classic FNHs. The role of percutaneous biopsy will also be detailed

89

Focal nodular hyperplasia  

Energy Technology Data Exchange (ETDEWEB)

Focal nodular hyperplasia is the second most common benign liver tumor after hemangioma and occurs predominantly in young women. Imaging techniques are crucial in the diagnosis of this lesion. In this article, we will present the imaging findings of the classic and non-classic FNHs. The role of percutaneous biopsy will also be detailed.

Vilgrain, Valerie [Department of Radiology, Hopital Beaujon, 100 Bd du General Leclerc, 92110 Clichy (France)]. E-mail: valerie.vilgrain@bjn.aphp.fr

2006-05-15

90

Cutaneous focal mucinosis  

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A 26-year-old male presented with asymptomatic, flesh coloured nodules on right elbow, forehead and right retroauricular region. A skin biopsy form the nodule stained with hematoxylin and eosin and special stain (mucicarmine) showed focal deposition of mucin in the dermis.

Gandhi Vijay; Dogra Devraj; Pandhi R

1996-01-01

91

Intra-articular angiolipoma of the knee: a case report  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract We report a case of intra-articular angiolipoma of the knee. This case report describes our experience in excising an intra-articular angiolipoma of the knee joint. Complete resection under arthroscopy was performed in a 30-year-old man. Two years after the surgery, no evidence of recurrence was seen. Intra-articular angiolipomas should be considered in the differential diagnosis of intra-articular masses in adolescents with recurrent hemarthrosis without trauma.

Nishimori Makoto

2010-04-01

92

Cartílago articular: Evaluación por resonancia magnética  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish El presente artículo revisa la evaluación imagenologica de las lesiones del cartílago articular con énfasis en su estudio por resonancia magnética, discutiendo la utilidad de las secuencias convencionales y los estudios avanzados de RM que permiten detectar lesiones condrales incipientes intrasustan [...] cia, previo a la ulceración de su superficie. Abstract in english This article reviews the radiographic evaluation of articular cartilage lesions with emphasis on its magnetic resonance imaging study, we will discuss the usefulness of conventional sequences and advanced MRI studies which allow detection of incipient intrasubstance chondral lesions, prior to the ul [...] ceration of its surface.

Gonzalo, Delgado P.

93

Characterisation of intra-articular soft tissue tumours and tumour-like lesions  

International Nuclear Information System (INIS)

The aim of this study was to describe a new magnetic resonance imaging (MRI) classification system for intra-articular soft tissue tumours based on the morphology of the lesion, with the aim to aid the differential diagnosis. We performed a retrospective review of 52 consecutive patients presenting to a specialist musculoskeletal oncology unit with a suspected intra-articular tumour. Lesions were categorised into one of four groups according to a simple classification system based on their morphological features on MRI. Distinct groupings of pathologies emerged corresponding to each of the morphological categories. Particularly when combined with radiographic features of calcification and bone erosion, certain patterns were found to be characteristic of specific diagnoses. For example multifocal, calcified lesions were found exclusively in synovial osteochondromatosis and diffuse synovitis with hypointense T2-weighted signal intensity was typical of pigmented villonodular synovitis. Certain combinations of imaging features such as diffuse solid lesions and focal lesions with bone erosion were commonly associated with malignant lesions. We suggest that by classifying intra-articular masses according to their morphological features on MRI, particularly when combined with simple radiographic features, an additional parameter may be generated to aid the radiologist in making a diagnosis. In addition, particular combinations of features provide 'red flags' to increase the tures provide 'red flags' to increase the index of suspicion for malignancy. (orig.)

94

Nefritis focal aguda: nuestra experiencia  

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La nefritis focal aguda se define como una lesión renal causada por infección focal aguda sin licuefacción. No es posible diferenciar mediante el cuadro clínico o de laboratorio una nefritis focal aguda de una pielonefritis aguda, siendo necesario el estudio de imagen. En las escasas publicaciones pediátricas al respecto, no existe uniformidad en las pautas de actuación diagnóstica y terapéutica. Presentamos una revisión de los casos de nefritis focal aguda diagnosticados y trata...

Penela Ve?lez Guevara, M. T.; Alarco?n Alacio, M. T.; Garci?a-vao Bel, C.; Rivero Marti?n, M. J.

2014-01-01

95

Focal nodular hyperplasia  

Directory of Open Access Journals (Sweden)

Full Text Available Thanks to ultrasonography, computed tomography, and nuclear magnetic resonance, not only symptomatic but also asymptomatic liver tumors are discovered more frequently than before. Focal nodular hyperplasia (FNH is one such tumor, most frequently an asymptomatic tumor of the liver, which predominantly appears in women during the generative period, who have taken oral contraceptives for several years. We present a 27-year-old woman, who has never taken either oral contraceptives or other hormones, in whom a left lobe liver tumor was unexpectedly discovered during a routine investigation performed for psychiatric complaints. The tumor, removed by left lateral bisegmentectomy (segments II and 111, was composed of two tumoral nodes: 70x58x47 mm and 20x20x20 mm, the bigger one of which had a light grey central stellate scar. Histology revealed a focal nodular hyperplasia. The postoperative recovery was uneventful and the patient stayed symptom free for more than three years after surgery.

?olovi? Radoje

2005-01-01

96

Repair of articular cartilage and meniscal tears by photoactive dyes: in-vivo study  

Science.gov (United States)

We describe healing results of our 6 month study of a repair procedure which evokes the healing response in meniscal tears and partial thickness defects in articular cartilage by a non-thermal tissue sparing photochemical weld using 1,8-naphthalimide dyes. Welds of incisional flaps in adult sheep meniscus and femoral articular cartilage were made using the dye MBM Gold 012011012 at 12 mM in PBS, 457.9nm Argon ion laser radiation at 800 mW/cm2, 7.5 minutes with approximately 1 kg/cm2 externally applied pressure. Gross appearance of tissues in all welded knees appeared normal. Hematoxylin and eosin stained sections disclosed close bonding of welded areas and continuing healing response as cellular recruitment.

Judy, Millard M.; Jackson, Robert W.; Nosir, Hany R.; Matthews, James Lester; Lewis, David E.; Utecht, Ronald E.; Yuan, Dongwu

1996-12-01

97

Focal nodular hyperplasia  

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Thanks to ultrasonography, computed tomography, and nuclear magnetic resonance, not only symptomatic but also asymptomatic liver tumors are discovered more frequently than before. Focal nodular hyperplasia (FNH) is one such tumor, most frequently an asymptomatic tumor of the liver, which predominantly appears in women during the generative period, who have taken oral contraceptives for several years. We present a 27-year-old woman, who has never taken either oral contraceptives or other hormo...

?olovi? Radoje; Grubor Nikica; Radak Vladimir; ?olovi? Nataša

2005-01-01

98

Childhood Focal Epilepsies  

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Full Text Available Objective: The present study was done in order to obtain a baseline profile of childhood focal epilepsies Patient and methods: Subjects included in this study were children suffering from focal epilepsy with age above 2 y. They were attending pediatric neurology clinic in Queen Rania Hospital for children in Jordan . The study included 112 children with ages ranging from 2-14 years. The following data were obtained: age, sex, detailed of seizures type, age at first unprovoked seizure, family history of seizure disorders, history and type of febrile seizures, etiological factors, socioeconomic class, history of consanguinity, additional neuro -impairment, Electroencephalography and brain imaging finding and the use of antiepileptic drugs, the results were recorded for further study. Results: A total of 112 consecutive cases of focal epilepsy were enrolled , 59 were male. The commonest partial seizure recorded was simple partial type 52 (46.4% while simple partial with secondary generalization had 17 (16.9% and complex partial seizure formed 36.8 %. , In partial onset seizures the peak age was between 11-14 years and complex partial seizures plateau was seen between ages 6-10 years. Twenty six (23.2% patients reported a family history of epilepsy, 91% of low socioeconomic class .11.5 % of cases have history of febrile seizures, idiopathic epilepsy was 53.5 % . In most of epileptic patients have accessory neurological impairment, the most common were learning difficulties Electroencephalography was normal in 20.4 %, mono-therapy was used in 68.8 % Conclusion: the pattern of focal epilepsies in our country do not differ from that of developed countries, further population ­based epidemiological research is indicated to confirm the prevalence of seizure disorders in this locality

Wael hayel khreisat

2011-04-01

99

[Focal nodular liver hyperplasia].  

Science.gov (United States)

It was evaluated the frequency of focal nodular liver hyperplasia and treatment resultsin 1425 patients for the last 17 years in 2 time period. The own experience and literature data were used. First this disease was considered as very rare liver tumor because of underdeveloped diagnostics. Tumor detection was the indication for laparotomy. In some patients removal of the tumor was not performed if intraoperativebiopsy has shown tumor benign. The indication for dynamic observation and surgical treatment were identified with increasing number of patients, diagnostics improvement, and analysis of immediate and long-term results. The operation provides persistentcure. PMID:25327673

Pyshkin, S A; Borisov, D L; Maslov, V G; Gorfinkel', A N

2014-01-01

100

Focal nodular hyperplasia  

International Nuclear Information System (INIS)

One case of focal nodular hyperplasia of the liver was reported. Time activity curves of the hepatobiliary scintigraphy were evaluated. The peak time, T1/2 in excretion phase and mean transit time of the FNH were longer than the normal liver and 13.8 min, 41.8 min and 22.7 min, respectively. Proliferation of the bile duct cell and stenosis of the bile duct were not shown pathologically. Dysfunction of the hepatocytes may cause retention of the 99mTc-EHIDA in this case. (author)

 
 
 
 
101

Focal limb dystonia.  

Science.gov (United States)

Limb dystonia (LD) refers to dystonia affecting one arm or leg. Depending on the site of onset, age at onset, and the etiology, progression and prognosis will be different. Usually young-onset primary dystonia affects the lower limbs and tends to generalize, while in adult-onset, it appears in the arm and remains focal. Lower limb dystonia in adults is rare as a primary cause, and parkinsonism or other neurological diseases must always be ruled out. In the text that follows, we review the main clinical features of the primary and secondary limb dystonias considering the age at onset and etiology. PMID:20590804

Pont-Sunyer, C; Martí, M J; Tolosa, E

2010-07-01

102

Focal nodular hyperplasia  

International Nuclear Information System (INIS)

This paper reports on the diagnostic value of MR imaging in a surgical series of focal nodular hyperplasia and to compare the signal intensity of the scar on MR imaging with histopathologic findings. During the past 3 years, 30 patients underwent liver resection for focal nodular hyperplasia. All patients underwent preoperative MR imaging examination with T1- and T2-weighted sequences. The MR findings of the scar (size, signal intensity) were correlated with the macroscopic and histopathologic results (fibrosis, edema, vessels, inflammation). Surgery disclosed 40 tumors in 30 patients (multiple in 7 cases). MR imaging failed to depict 6 tumors of 2 cm in diameter. Correct diagnosis was made in 12 of the 34 tumors seen with MR imaging (35%). In the other cases, there were atypical features, no scar, hypointense scar on T2-weighted sequences, and peritumoral halo. Macroscopic evaluation off the scar (presence, size) correlated well with the MR imaging findings. Furthermore, in 13 of the 16 hyperintense scars on T2-weighted sequences, microscopic examination revealed predominant edema and vessels. In 4 of the 6 hypointense scars on T2-weighted sequences, microscopic examination revealed a low content of edema and vessels

103

EPIC-?CT imaging of articular cartilage.  

Science.gov (United States)

Characterization of articular cartilage morphology and composition using microcomputed tomography (microCT) techniques requires the use of contrast agents to enhance X-ray attenuation of the tissue. This chapter describes the use of an anionic iodinated contrast agent at equilibrium with articular cartilage. In this technique, negatively charged contrast agent molecules distribute themselves inversely with respect to the negatively charged proteoglycans (PGs) within the cartilage tissue (Palmer et al. Proc Natl Acad Sci U S A 103:19255-19260, 2006). This relationship allows for assessment of cartilage degradation, as areas of high X-ray attenuation have been shown to correspond to areas of depleted PGs (Palmer et al. Proc Natl Acad Sci U S A 103:19255-19260, 2006; Xie et al. Osteoarthritis Cartilage 18:65-72, 2010). PMID:25331048

Lin, Angela S P; Salazar-Noratto, Giuliana E; Guldberg, Robert E

2015-01-01

104

Juxta-articular large cell lymphoma  

International Nuclear Information System (INIS)

Three patients with juxta-articular large cell lymphoma presented as suffering from monarthropathies. A spectrum of radiographic changes was observed that included subchondral sclerosis, regional osteopenia, effusion, and mottled lytic changes in the juxta-articular region of the affected joint. MRI was performed in two patients. In one, it revealed at high signal mass on T2-weighted sequences. In the second, a mass bridging the joint was demonstrated which was difficult to appreciate on CT and was not visible radiographically. In all cases, biopsies revealed large cell non-Hodgkin's lymphoma of bone. We present these studies to emphasize this unusual pattern of non-Hodkin's lymphoma as well as to demonstrate the contribution of MRI to the diagnosis. (orig.)

105

Articular cartilage collagen: an irreplaceable framework?  

Directory of Open Access Journals (Sweden)

Full Text Available Adult articular cartilage by dry weight is two-thirds collagen. The collagen has a unique molecular phenotype. The nascent type II collagen fibril is a heteropolymer, with collagen IX molecules covalently linked to the surface and collagen XI forming the filamentous template of the fibril as a whole. The functions of collagens IX and XI in the heteropolymer are far from clear but, evidently, they are critically important since mutations in COLIX and COLXI genes can result in chondrodysplasia syndromes. Here we review what is known of the collagen assembly and present new evidence that collagen type III becomes covalently added to the polymeric fabric of adult human articular cartilage, perhaps as part of a matrix repair or remodelling process.

D R Eyre

2006-11-01

106

Effect of initial cell seeding density on 3D-engineered silk fibroin scaffolds for articular cartilage tissue engineering  

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The repair of articular cartilage defects poses a continuing challenge. Cartilage tissue engineering through the culture of chondrocytes seeded in 3D porous scaffolds has the potential for generating constructs that repair successfully. It also provides a platform to study scaffold-cell and cell-cell interactions. The scaffold affects the growth and morphology of cells growing on it, and concomitantly, cells affect the properties of the resultant tissue construct. Silk fibroin protein from An...

Talukdar, Sarmistha; Nguyen, Quynhhoa T.; Chen, Albert C.; Sah, Robert L.; Kundu, Subhas C.

2011-01-01

107

Articular cartilage collagen: an irreplaceable framework?  

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Adult articular cartilage by dry weight is two-thirds collagen. The collagen has a unique molecular phenotype. The nascent type II collagen fibril is a heteropolymer, with collagen IX molecules covalently linked to the surface and collagen XI forming the filamentous template of the fibril as a whole. The functions of collagens IX and XI in the heteropolymer are far from clear but, evidently, they are critically important since mutations in COLIX and COLXI genes can result in chondrodysplasia ...

Eyre, D. R.; Weis, M. A.; J-j, Wu

2006-01-01

108

Statistical earthquake focal mechanism forecasts  

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Forecasts of the focal mechanisms of future earthquakes are important for seismic hazard estimates and Coulomb stress and other models of earthquake occurrence. Here we report on a high-resolution global forecast of earthquake rate density as a function of location, magnitude, and focal mechanism. In previous publications we reported forecasts of 0.5 degree spatial resolution, covering the latitude range magnitude, and focal mechanism. In previous publications we reported fo...

Kagan, Yan Y.; Jackson, David D.

2013-01-01

109

Intra-articular depot forming drug delivery system for osteoarthritis  

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Osteoarthritis (OA) is a chronic degenerative disease of the joint. Current treatments for this disease (such as glucocorticoid steroids) aim to reduce pain and increase mobility. Intra-articular injection is used in OA as treatment can be targeted to affected joints only. There is currently a lack of sustained release formulations for intra-articular injection. The aim of this thesis was to produce and characterise an injectable intra-articular drug delivery system capable of providing d...

Freddi, Matthew James

2012-01-01

110

Systemic focal epileptogenesis  

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Rats that receive radiation to 0.25 cc of one cerebral hemisphere are clinically and electroencephalographically normal until there is a breakdown of the blood-brain barrier (BBB) at 3 to 6 months postradiation. This BBB lesion can be detected by transient focal seizure activity produced by the BBB-excluded systemic convulsant bicuculline methiodide. In two rats the seizure activity induced by this one injection was self-sustaining. In seven of 15 other rats tested, the subsequent administration of repeated 2 mg/kg injections created a chronic focus that continued to spike with great frequency for 3 weeks or more without further administration of any convulsant. In three of eight other rats, implanted minipumps delivering 180 micrograms/h of bicuculline methiodide produced self-sustaining epileptic activity.

Remler, M.P.; Marcussen, W.H.

1986-01-01

111

Proximal Focal Femoral Deficiency  

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Full Text Available Proximal focal femoral deficiency (PFFD is a developmental disorder of the proximal segment of thefemur and of acetabulum resulting in shortening of the affected limb and impairment of the function. It isa spectrum of congenital osseous anomalies characterized by a deficiency in the structure of the proximalfemur. The diagnosis is often made by radiological evaluation which includes identification and descriptionof PFFD and evaluation of associated limb anomalies by plain radiographs. Contrast arthrography orMagnetic Resonance Imaging is indicated when radiological features are questionable and to disclose thepresence and location of the femoral head and any cartilagenous anlage. The disorder is more commonlyunilateral and is apparent at birth. However, bilateral involvement is rarely seen. Therapy of the disorder isdirected towards satisfactory ambulation and specific treatment depending on the severity of dysplasia.

Vishal Kalia, Vibhuti

2008-01-01

112

Response of slowly adapting articular mechanoreceptors in the cat knee joint to alterations in intra-articular volume.  

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Recordings were obtained from slowly adapting mechanoreceptors innervating the posterior aspect of the cat knee joint capsule. It was observed that, with rising intra-articular volume, initially both intra-articular pressure and the neural discharge increased. This increase was dependent on the rate of fluid accumulation within the joint. However, the joint nerve discharge invariably levelled out despite increasing intra-articular volume and pressure. This suggests that there exists some limi...

Wood, L.; Ferrell, W. R.

1984-01-01

113

Statistical earthquake focal mechanism forecasts  

CERN Document Server

Forecasts of the focal mechanisms of future earthquakes are important for seismic hazard estimates and Coulomb stress and other models of earthquake occurrence. Here we report on a high-resolution global forecast of earthquake rate density as a function of location, magnitude, and focal mechanism. In previous publications we reported forecasts of 0.5 degree spatial resolution, covering the latitude range magnitude, and focal mechanism. In previous publications we reported forecasts of 0.5 degree spatial resolution, covering the latitude range from -75 to +75 degrees, based on the Global Central Moment Tensor earthquake catalog. In the new forecasts we've improved the spatial resolution to 0.1 degree and the latitude range from pole to pole. Our focal mechanism estimates require distance-weighted combinations of observed focal mechanisms within 1000 km of each grid point. Simultaneously we calculate an average rotation angle between the forecasted mechanism and all the surrounding mechanisms, using the method ...

Kagan, Yan Y

2013-01-01

114

Nanosized fibers' effect on adult human articular chondrocytes behavior.  

Science.gov (United States)

Tissue engineering with chondrogenic cell based therapies is an expanding field with the intention of treating cartilage defects. It has been suggested that scaffolds used in cartilage tissue engineering influence cellular behavior and thus the long-term clinical outcome. The objective of this study was to assess whether chondrocyte attachment, proliferation and post-expansion re-differentiation could be influenced by the size of the fibers presented to the cells in a scaffold. Polylactic acid (PLA) scaffolds with different fiber morphologies were produced, i.e. microfiber (MS) scaffolds as well as nanofiber-coated microfiber scaffold (NMS). Adult human articular chondrocytes were cultured in the scaffolds in vitro up to 28 days, and the resulting constructs were assessed histologically, immunohistochemically, and biochemically. Attachment of cells and serum proteins to the scaffolds was affected by the architecture. The results point toward nano-patterning onto the microfibers influencing proliferation of the chondrocytes, and the overall 3D environment having a greater influence on the re-differentiation. In the efforts of finding the optimal scaffold for cartilage tissue engineering, studies as the current contribute to the knowledge of how to affect and control chondrocytes behavior. PMID:23827606

Stenhamre, Hanna; Thorvaldsson, Anna; Enochson, Lars; Walkenström, Pernilla; Lindahl, Anders; Brittberg, Mats; Gatenholm, Paul

2013-04-01

115

Nanosized fibers' effect on adult human articular chondrocytes behavior  

International Nuclear Information System (INIS)

Tissue engineering with chondrogenic cell based therapies is an expanding field with the intention of treating cartilage defects. It has been suggested that scaffolds used in cartilage tissue engineering influence cellular behavior and thus the long-term clinical outcome. The objective of this study was to assess whether chondrocyte attachment, proliferation and post-expansion re-differentiation could be influenced by the size of the fibers presented to the cells in a scaffold. Polylactic acid (PLA) scaffolds with different fiber morphologies were produced, i.e. microfiber (MS) scaffolds as well as nanofiber-coated microfiber scaffold (NMS). Adult human articular chondrocytes were cultured in the scaffolds in vitro up to 28 days, and the resulting constructs were assessed histologically, immunohistochemically, and biochemically. Attachment of cells and serum proteins to the scaffolds was affected by the architecture. The results point toward nano-patterning onto the microfibers influencing proliferation of the chondrocytes, and the overall 3D environment having a greater influence on the re-differentiation. In the efforts of finding the optimal scaffold for cartilage tissue engineering, studies as the current contribute to the knowledge of how to affect and control chondrocytes behavior. - Highlights: ? Chondrocyte behavior in nanofiber-coated microfiber versus microfiber scaffolds ? High porosity (> 90%) and large pore sizes (a few hundred ?m) of nanofibrous scaffolds ? Proliferation enhanced by presence of nanofibers ? Differentiation not significantly affected ? Cell attachment improved in presence of both nanofibers and serum

116

Viral articular deformations in a goat  

International Nuclear Information System (INIS)

A goat belonging to an animal aid association was presented for bilateral deformation of the tarsus and carpus and signs of high-grade pain. ELISA serology was positive for Caprine Arthritis-Encephalitis Virus. Radiography revealed marked osseous remodelling of the tarsus. The blood fibrinogen concentration was very elevated. On infected commercial farms, it is recommended that both seropositive animals and their offspring are culled when the level of infected is low, or to separate the kids from the mothers at an early age. In this case, palliative treatment was prescribed based on non-steroidal anti-inflammatory drugs, antibiotics and articular puncture-lavages

117

[Extra-articular manifestations of chronic polyarthritis].  

Science.gov (United States)

Although the chronic destructive joint processes dominate the clinical picture of chronic rheumatoid arthritis, it must not been forgotten that the disease is a systemic one, whereby certain organs or organ systems are affected either clinically or subclinically. The various possible pathogenetic mechanisms are discussed and the particular type of patient with rheumatoid arthritis who appears to be prone to extra-articular manifestations is described. Subsequently, the individual organic manifestations and the clinical picture are discussed, as well as the incidence and significance of these features. PMID:960707

Siegmeth, W; Eberl, R

1976-02-01

118

Advances in treatment of articular cartilage injuries  

Directory of Open Access Journals (Sweden)

Full Text Available Cartilage is a kind of terminally differentiated tissue devoid of vessel or nerve, and it is difficult to repair by itself after damage. Many studies for the treatment of cartilage injuries were performed in recent years aiming at repair of the structure and restoration of its function for injured joint. This article reviews the traditional methods of treatment for cartilage injuries, such as joint lavage with the aid of arthroscope, abrasion chondroplasty, laser abrasion and chondroplasty, and drilling of the subchondral bone-marrow space. The research advances in treatment of articular cartilage injuries with tissue engineering were summarized.

Yuan-cheng LI

2013-05-01

119

Focal nodular hyperplasia (FNH).  

Science.gov (United States)

Focal nodular hyperplasia (FNH) is a benign tumour of the liver (hepatic tumour), which is the second most prevalent tumour of the liver (the first is hepatic hemangioma). It has a higher incidence in females, 20-40 years old, but also occurs in men and even in children. It is usually asymptomatic, rarely grows or bleeds, and has no malignant potential. This tumour was once often resected because it was difficult to distinguish from hepatic adenoma, but with modem multiphase imaging it is now diagnosed strictly by imaging criteria, and not resected. We present the case of a 78 years old man who presented to emergency room (ER) with a history of dry cough, chest pain and mild dyspnea. Chest X-ray showed ascension of the right hemidiaphragm, and a homogeneous round opacity of 6/6.2 cm in the right cardiophrenic angle. The first suspicion was of pulmonary tumor, but the final diagnosis was FNH, confirmed by CT scan. We discuss the differential diagnosis and prognosis of this entity. The particularities of the case are the presentation with respiratory symptoms and pulmonary mass, and the age of the patient. PMID:25000678

Nat, Laura; Poant?, Laura Irina

2014-01-01

120

Ankylosing spondylitis presenting as juxta-articular masses in females  

International Nuclear Information System (INIS)

Juxta-articular inflammatory masses, sternomanubrial or sternoclavicular, were noted in two women who were subsequently found to have ankylosing spondylitis. The differential diagnosis of juxta-articular masses should include systemic rheumatic disorders as well as tumor or infection. (orig.)

 
 
 
 
121

Combined nanoindentation testing and scanning electron microscopy of bone and articular calcified cartilage in an equine fracture predilection site  

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Full Text Available Condylar fracture of the third metacarpal bone (Mc3 is the commonest cause of racetrack fatality in Thoroughbred horses. Linear defects involving hyaline articular cartilage, articular calcified cartilage (ACC and subchondral bone (SCB have been associated with the fracture initiation site, which lies in the sagittal grooves of the Mc3 condyle. We discovered areas of thickened and abnormally-mineralised ACC in the sagittal grooves of several normal 18-month-old horses, at the same site that linear defects and condylar fracture occur in older Thoroughbreds and questioned whether this tissue had altered mechanical properties. We embedded bone slices in PMMA, prepared flat surfaces normal to the articular surface and studied ACC and SCB using combined quantitative backscattered electron scanning electron microscopy (qBSE and nanoindentation testing: this allowed correlation of mineralisation density and tissue stiffness (E at the micron scale. We studied both normal and affected grooves, and also normal condylar regions. Large arrays of indentations could be visualised as 2-dimensional maps of E with a limit to resolution of indentation spacing, which is much larger than qBSE pixel spacing. ACC was more highly mineralised but less stiff in early linear defects than in control regions, while subchondral bone was more highly mineralised and stiffer in specimens with early linear defects than those without. Thus both ACC and SCB mineralisation may be abnormal in a class of early linear defect in 18-month-old Thoroughbred horses, and this may possibly contribute to later fracture of the Mc3 condyle.

M Doube

2010-06-01

122

Tiling the plane with noncongruent toric focal conic domains  

Science.gov (United States)

This paper deals with regular arrays of macroscopic defects (focal conic domains) observed when a slab of lamellar phase is sandwiched between two substrates imposing different orientational anchorings. We report, in particular, detailed observations of the texture of a lyotropic lamellar phase in contact with a glass substrate and a lyotropic sponge phase. We consider several models for the defects depending on the material and the substrate parameters. Their energy has a common form, and the main features of the textures are explained in the framework of a simple model where disks of different sizes tile a plane in order to minimize a particular interface energy. PMID:11102026

Blanc; Kleman

2000-11-01

123

Effect of epigallocatechin-3-gallate on proliferation and phenotype maintenance in rabbit articular chondrocytes in vitro.  

Science.gov (United States)

In autologous chondrocyte implantation (ACI) to restore defective cartilage, limited cell numbers and dedifferentiation of chondrocytes are the major difficulties. An alternative is the use of growth factors, but their high cost and potential for tumorigenesis are major obstacles. To ensure successful ACI therapy, it is important to find an effective substitute pro-chondrogenic agent. Epigallocatechin-3-gallate (EGCG), one of the green tea catechins, has been widely investigated in studies of interleukin-1?-induced chondrocytes. In the present study, the effects of EGCG on rabbit articular chondrocytes were investigated through the examination of cell proliferation, morphology, glycosaminoglycan synthesis and cartilage-specific gene expression. The results showed that EGCG could effectively promote chondrocyte growth and enhance the secretion and synthesis of the cartilage extracellular matrix by upregulating expression levels of aggrecan, collagen II and Sox9 genes. Expression of the collagen I gene was downregulated, which showed that EGCG effectively inhibited the dedifferentiation of chondrocytes. Hypertrophy, which may lead to chondrocyte ossification, was also undetectable in the EGCG groups. In conclusion, the recommended dose of EGCG was found to be in the range of 5 to 20 ?M, with the most marked response observed with 10 ?M. The present study may provide a basis for the development of a novel agent as a substitute for growth factors in the treatment of articular cartilage defects. PMID:25452805

Huang, Haojia; Liu, Qin; Liu, Lei; Wu, Huayu; Zheng, Li

2015-01-01

124

[Extra-articular manifestations of rheumatoid arthritis].  

Science.gov (United States)

Rheumatoid arthritis (RA) represents an autoimmune disease affecting mostly joints, in particular small finger and toe joints. In addition RA can show extra-articular manifestations in many organs. Information on the frequency of extra-articular manifestations (EAMs) in RA varies greatly in different publications from 17.8% to 40.9% and EAMs tend to become higher with increasing duration and severity of the disease. The exact etiology and pathogenesis are still unclear but vasculitic alterations together with deposition of immune complexes can often be found histopathologically in affected organs. It must also be taken into consideration that EAMs can also be a result of the pharmaceutical therapy. The organ findings can vary greatly which is also reflected in the multitude of clinical symptoms. Possible target organs are the blood vessels, kidneys, central nervous system, cardiovascular system, the lungs, eyes, skin, nails as well as blood and the hemopoetic system. The prognosis for RA becomes progressively worse in the presence of EAMs. Regular and continuous control investigations are necessary in order to be able to diagnose EAMs early and to begin therapy. Therapy includes the administration of non-steroidal anti-inflammatory drugs (NSAIDs) and disease-modifying antirheumatic drugs (DMARDs) and especially in advanced stages cyclophosphamide or biologicals. Therapy is still very empirical due to the lack of appropriate studies. PMID:22932980

Baerwald, C; Kneitz, C; Bach, M; Licht, M

2012-12-01

125

Hot spot liver scan in focal nodular hyperplasia  

International Nuclear Information System (INIS)

In scintigraphy of the liver with radiocolloid, space-occupying lesions generally are visualized as regions of decreased accumulation of radioactivity. Rarely focal areas of increased activity are depicted; most are related to altered vascular dynamics in the liver secondary to obstruction of the superior or inferior vena cava or the hepatic veins. There are reports of single cases of focally increased activity due to a hepatic hemangioma, hepatic venoocclusive disease, herniation of a part of the liver, and a liver hot spot found after radiocolloid injection via a malpositioned central venous catheter in one of the hepatic vein branches. In patients with focal nodular hyperplasia, liver scans with solitary defects as well as normal patterns are found. In some cases, increased uptake of colloid in the lesion has been documented. Pasquier and Dorta reported a patient with a palpable mass in the left liver lobe with increased accumulation of radioactivity on the radiocolloid liver scan. The histologic diagnosis was hamartoma, but reviewing the description and considering the confusion in the past concerning the nomenclature, this case is suggestive of focal nodular hyperplasia. We report a patient with focal nodular hyperplasia who had increased radiocolloid uptake in the lesion. The radionuclide studies are compared with angiography, sonography, and computed tomography. An explanation for the localized increased colloid accumulation based on histologic findings is suggation based on histologic findings is suggested

126

Focal Rigidity of Flat Tori  

CERN Document Server

Given a closed Riemannian manifold (M, g), there is a partition \\Sigma_i of its tangent bundle TM called the focal decomposition. The sets \\Sigma_i are closely associated to focusing of geodesics of (M, g), i.e. to the situation where there are exactly i geodesic arcs of the same length joining points p and q in M. In this note, we study the topological structure of the focal decomposition of a closed Riemannian manifold and its relation with the metric structure of the manifold. Our main result is that the flat n-tori are focally rigid, in the sense that if two flat tori are focally equivalent, then the tori are isometric up to rescaling.

Kwakkel, Ferry; Peixoto, Mauricio

2011-01-01

127

Diagnostic imaging in focal epilepsy  

International Nuclear Information System (INIS)

Focal epilepsies account for 60% of all seizure disorders worldwide. In this review the classic and new classification system of epileptic seizures and syndromes as well as genetic forms are discussed. Magnetic resonance (MR) is the technique of choice for diagnostic imaging in focal epilepsy because of its sensitivity and high tissue contrast. The review is focused on the lack of consensus of imaging protocols and reported findings in refractory epilepsy. The most frequently encountered MRI findings in epilepsy are reported and their imaging characteristics are depicted. Diagnosis of hippocampal sclerosis and malformations of cortical development as two major causes of refractory focal epilepsy is described in details. Some promising new techniques as positron emission tomography computed tomography (PET/CT) and MR and PET/CT fusion are briefly discussed. Also the relevance of adequate imaging in focal epilepsy, some practical points in imaging interpretation and differential diagnosis are highlighted. (author)

128

Focal amyotrophy in neurofibromatosis 2  

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Neurofibromatosis type 2 (NF2) is an autosomal dominant disorder characterised by bilateral vestibular schwannomas and other CNS tumours including meningiomas and spinal schwannomas. Occasionally, peripheral neuropathy occurs in these patients but this is the first report of focal amyotrophy. Clinical, electrophysiological, and imaging data from four NF2 patients seen at a specialist neurofibromatosis clinic over a 4 year period are described in whom symptomatic focal amyotrophy p...

Trivedi, R.; Byrne, J.; Huson, S.; Donaghy, M.

2000-01-01

129

MRI of Focal Liver Lesions  

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Magnetic resonance imaging, MRI has more advantages than ultrasound, computed tomography, CT, positron emission tomography, PET, or any other imaging modality in diagnosing focal hepatic masses. With a combination of basic T1 and T2 weighted sequences, diffusion weighted imaging, DWI, and hepatobiliary gadolinium contrast agents, that is gadobenate dimeglumine (Gd-BOPTA) and gadoxetic acid (Gd-EOB), most liver lesions can be adequately diagnosed. Benign lesions, as cyst, hemangioma, focal nod...

Albiin, Nils

2012-01-01

130

EVALUACIÓN DEL CARTÍLAGO ARTICULAR CON RESONANCIA MAGNÉTICA ASSESSMENT OF ARTICULAR CARTILAGE USING MAGNETIC RESONANCE IMAGING  

Directory of Open Access Journals (Sweden)

Full Text Available Las lesiones del cartílago articular son frecuentes y su diagnóstico por imagen cada día más importante. La resonancia magnética es el método de diagnóstico por imagen de elección para la evaluación de lesiones condrales. Este artículo revisa la utilidad de este método, en relación a estudios convencionales así como también estudios avanzados, cuantitativos, que permiten evaluar alteraciones condrales iniciales antes de ser evidentes en secuencias habituales de resonancia magnética.Articular cartilage injuries is a common event and imaging technique has become increasingly important in diagnosing them. Magnetic Resonance Imaging (MRI is the imaging method of choice forthe evaluation of chondral lesions. This article reviews the usef ulness of this method compared to conventional as well as to advanced quantitative studies, thus enabling evaluation of initial cartilage alterations before being evident in normal MRI sequences.

Gonzalo Delgado P

2009-01-01

131

Osteo-articular manifestations of amyloidosis.  

Science.gov (United States)

Whether it is overload disease or mispleated proteins, amyloid is a great pretender. This is especially true for all of the osteo-articular manifestations of amyloid light chain (AL) amyloidosis, which may mimic rheumatoid arthritis, polymyalgia rheumatica, a myeloma or a bone tumour. To improve the prognosis, AL amyloidosis must be considered in front of atypical osteo-articular manifestations. Amyloidosis Ab2M of chronic haemodialysis (members' arthropathy and destructive spondylitis) is a specific entity that needs to be differentiated from other osteoarthropathies of chronic renal failure. It has become exceptional since the progress of haemodialysis. Finally transthyretin amyloidosis(ATTR) can be responsible for carpal tunnel syndrome(CTS) in its genetic and senile form. Although amyloidosis is rare, it represents one of the aetiologies of CSC, regardless of its type. In the specific context of haemodialysis, this poses no difficulty for the clinician. Yet AL amyloidosis must be considered more often, as must senile amyloidosis ATTR in the elderly. It seems obvious that the anatomo-pathologic analysis with specific staining with Congo red - see typing - should be systematically performed in the case of surgical neurolysis. Amyloidosis is defined by the extracellular deposit of proteins which share common tinctorial affinities, a fibril aspect under electron microscopy and spatial conformation called beta pleated. Once regarded as a mere overload disease, it is currently considered as a disease of misfolded proteins. Indeed, it is certain that abnormalities of spatial pattern play an essential role in the responsibility for the pathology of many proteins whose amyloid fibre is the final common way. They involve both changes in the conformation of proteins and other major in vivo interactions between amyloid protein and the extracellular matrix. In most cases, amyloidosis represents the bulk of histopathological lesions and its pathogenic role is certain. In other cases, it is only one elementary lesion of the disease and its role is controversial. The amyloidosis responsible for osteo-articular manifestations are the AL immunoglobulin amyloidosis, the beta2-microglobulin amyloidosis in patients under haemodialysis and finally the amyloidosis of transthyretin (genetic and senile). Rheumatological manifestations of immunoglobulin amyloidosis are numerous and often indicative of the disease. Deposits affect joint and periarticular structures. The most common presentation is a progressively developing bilateral symmetric polyarthritis with negative immunology and absent specific structural abnormalities. Carpal tunnel syndrome (CTS) is very common and should suggest the aetiology. Other clinical representations are rarer as an isolated bone tumour (amyloidoma) or integrating systemic AL amyloidosis. ? 2-Microglobulin amyloidosis occurs in patients under chronic haemodialysis. It is responsible for CTS, arthralgia and above all a specific destructive spondyloarthropathy. The transthyretin amyloidosis also causes CTS. PMID:23040361

M'bappé, Pauline; Grateau, Gilles

2012-08-01

132

Imaging diagnosis of the articular cartilage disorders  

International Nuclear Information System (INIS)

Objective: To evaluate the diagnosis and differential diagnosis among the chronic osteoarthritis, rheumatoid arthritis and other chronic cartilage lesions on the plain films and MR images. Methods: Eighty-nine cases, including 115 joints, underwent plain film and MRI examination, and enhanced MRI scan was performed on 32 of them, including 44 joints. MRI scan sequences consisted of T1WI, T2WI + PDWI, STIR, and 3D FS SPGR. There were 90 knee joints in this group and each of the articular cartilage was divided into four parts: patella, femoral medial condyle, femoral lateral condyle, and tibia facet on MR images. The cartilage disorders were classified according to the outerbridge method. In addition, 61 cases including 75 joints were observed as a control group on the plain films and MR images. Results: 115 cartilage lesions were found on MR images, in which thinness of the cartilage (58 cases, 50.4%), bone changes under the cartilage (22 cases, 19.7%), medullar edema (22 cases, 19.7%), and synovial hyperplasia (52 cases, 45.2%) were seen. The patella cartilage was the most likely affected part (81/90, 90%). So the patellar cartilage lesions were divided as group 1 (grade I-II) and group 2 (grade III-IV) on MR images, which were compared with the plain film signs. The narrowing of the joint space and saccules under the articular surface were statistically significant with each other, and ?2 values were 9.349 and 9.885, respectively (P=es were 9.349 and 9.885, respectively (P=0.002). Conclusion: No constant signs could be seen on the plain films with grade I-II cartilage disorders. While the narrowing joint space and saccules under the joint surface could be seen on them with grade III-IV cartilage disorders, which were mainly correlated with the cartilage disorders and bone changes under the articular cartilages. A combination of the plain films and MR images is the best imaging method for examining the joints and joint cartilages. Enhanced MRI scan is very helpful on the diagnosis and differential diagnosis of the synovial lesions

133

EVALUACIÓN DEL CARTÍLAGO ARTICULAR CON RESONANCIA MAGNÉTICA ASSESSMENT OF ARTICULAR CARTILAGE USING MAGNETIC RESONANCE IMAGING  

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Las lesiones del cartílago articular son frecuentes y su diagnóstico por imagen cada día más importante. La resonancia magnética es el método de diagnóstico por imagen de elección para la evaluación de lesiones condrales. Este artículo revisa la utilidad de este método, en relación a estudios convencionales así como también estudios avanzados, cuantitativos, que permiten evaluar alteraciones condrales iniciales antes de ser evidentes en secuencias habituales de resonancia magné...

Gonzalo Delgado P

2009-01-01

134

Modelos computacionales del comportamiento del cartílago articular / Computational models of articular cartilage behavior  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish El cartílago articular suministra a las articulaciones diartrodiales baja fricción, resistencia al desgaste en las superficies de contacto y distribuye los esfuerzos en las zonas donde se presenta contacto con el hueso; adicionalmente, es un tejido alinfático y avascular, razón por la cual su regene [...] ración toma demasiado tiempo y en pacientes con avanzada edad no es posible realizarla. Con el propósito de estudiar y entender completamente el comportamiento del cartílago bajo diferentes condiciones de carga y en presencia de enfermedades como la osteoartritis, se han creado diferentes modelos computacionales que incluyen características propias de la estructura del tejido cartilaginoso que permiten predecir su comportamiento en condiciones normales y anormales, disminuyendo tiempos y costos de experimentación. Este artículo de actualización expone las principales características estructurales y biológicas del cartílago articular y presenta diferentes modelos computacionales que permiten modelar el tejido cartilaginoso de acuerdo con sus principales características y de esta forma simular el deterioro del cartílago bajo diferentes condiciones y enfermedades. Abstract in english The articular cartilage provides diarthrodial articulations with low friction, resistance to wear on contact surfaces, and an effective distribution of efforts in areas of contact with the bone. On the other hand, because their tissue is alymphatic and avascular, regeneration takes a long time and i [...] s not possible in elderly patients. Various computational models have been developed to study and fully understand cartilage behavior under varying load conditions and in the presence of diseases such as osteoarthritis. The models include specific features of cartilaginous tissue allowing to predict its behavior in normal and abnormal conditions, reducing experimentation time and costs. This update paper presents the main structural and biological characteristics of the articular cartilage, as well as various computational models representing cartilaginous tissue according to its main features, with a view to simulating cartilage deterioration under varying conditions and diseases.

Oscar Rodrigo, López-Vaca; Carlos Alberto, Narváez-Tovar; Diego Alexander, Garzón-Alvarado.

2012-09-01

135

Modelos computacionales del comportamiento del cartílago articular Computational models of articular cartilage behavior  

Directory of Open Access Journals (Sweden)

Full Text Available El cartílago articular suministra a las articulaciones diartrodiales baja fricción, resistencia al desgaste en las superficies de contacto y distribuye los esfuerzos en las zonas donde se presenta contacto con el hueso; adicionalmente, es un tejido alinfático y avascular, razón por la cual su regeneración toma demasiado tiempo y en pacientes con avanzada edad no es posible realizarla. Con el propósito de estudiar y entender completamente el comportamiento del cartílago bajo diferentes condiciones de carga y en presencia de enfermedades como la osteoartritis, se han creado diferentes modelos computacionales que incluyen características propias de la estructura del tejido cartilaginoso que permiten predecir su comportamiento en condiciones normales y anormales, disminuyendo tiempos y costos de experimentación. Este artículo de actualización expone las principales características estructurales y biológicas del cartílago articular y presenta diferentes modelos computacionales que permiten modelar el tejido cartilaginoso de acuerdo con sus principales características y de esta forma simular el deterioro del cartílago bajo diferentes condiciones y enfermedades.The articular cartilage provides diarthrodial articulations with low friction, resistance to wear on contact surfaces, and an effective distribution of efforts in areas of contact with the bone. On the other hand, because their tissue is alymphatic and avascular, regeneration takes a long time and is not possible in elderly patients. Various computational models have been developed to study and fully understand cartilage behavior under varying load conditions and in the presence of diseases such as osteoarthritis. The models include specific features of cartilaginous tissue allowing to predict its behavior in normal and abnormal conditions, reducing experimentation time and costs. This update paper presents the main structural and biological characteristics of the articular cartilage, as well as various computational models representing cartilaginous tissue according to its main features, with a view to simulating cartilage deterioration under varying conditions and diseases.

Oscar Rodrigo López-Vaca

2012-09-01

136

Variations in thickness of articular cartilage in the human sacroiliac joint.  

Science.gov (United States)

Differences in articular cartilage thickness in the sacroiliac joint were investigated in different regions of the sacral and the iliac articular surfaces in the embalmed cadavers of five males and six females. The mean thickness of the sacral articular cartilage was greater than that of the iliac articular cartilage (P < 0.001) and the sacral articular cartilage of the female was thicker than that of the male (P < 0.02). Differences between thicknesses of the iliac articular cartilage in the male and female and in different regions of the sacral and iliac articular cartilages were found to be not significant. PMID:8713157

Salsabili, N; Valojerdy, M R; Hogg, D A

1995-01-01

137

Tantalum oxide nanoparticles for the imaging of articular cartilage using X-ray computed tomography: visualization of ex vivo/in vivo murine tibia and ex vivo human index finger cartilage.  

Science.gov (United States)

The synthesis and characterization of tantalum oxide (Ta2O5) nanoparticles (NPs) as new X-ray contrast media for microcomputed tomography (?CT) imaging of articular cartilage are reported. NPs, approximately 5-10?nm in size, and possessing distinct surface charges, were synthesized using phosphonate (neutral), ammonium (cationic), and carboxylate (anionic) ligands as end functional groups. Assessment of a cartilage defect in a human cadaver distal metacarpophalangeal (MCP) joint with the ammonium nanoparticles showed good visualization of damage and preferential uptake in areas surrounding the defect. Finally, an optimized nontoxic cationic NP contrast agent was evaluated in an in?vivo murine model and the cartilage was imaged. These nanoparticles represent a new type of contrast agent for imaging articular cartilage, and the results demonstrate the importance of surface charge in the design of nanoparticulate agents for targeting the surface or interior zones of articular cartilage. PMID:24981730

Freedman, Jonathan D; Lusic, Hrvoje; Snyder, Brian D; Grinstaff, Mark W

2014-08-01

138

Arthoscopy La artroscopia y las lesiones articulares  

Directory of Open Access Journals (Sweden)

Full Text Available

A general view is presented on arthroscopy; its history, indications and limitations are described and analyzed; its advantages in comparison with open surgery are emphasized.

La artroscopia es un procedimiento que permite, mediante un instrumento óptico, evaluar el Interior de las cavidades articulares. Comenzó a desarrollarse como un procedimiento diagnóstico y pronto sus grandes ventajas frente a las exploraciones abiertas aceleraron el desarrollo de las técnicas y del instrumental. La minimización del trauma a los tejidos y la menor morbilidad posoperatoria permiten que la deambulación y la recuperación funcional sean precoces lo cual, sumado a un mejor resultado estético, ha colocado a la artroscopia como procedimiento de elección para el diagnóstico y el tratamiento de múltiples estados patológicos intraarticulares.

Raúl J. Naranjo

1991-01-01

139

Lesiones focales hepáticas en niños / Focal liver lesions in children  

Scientific Electronic Library Online (English)

Full Text Available SciELO Venezuela | Language: Spanish Abstract in spanish Introducción: Las lesiones focales del hígado comprenden un grupo heterogéneo de entidades como tumores benignos y malignos, sólidos o quistes, vasculares, masas inflamatorias y metástasis, entre otras. Objetivo: reportar lesiones focales hepáticas en niños, características clínicas, estudios por im [...] ágenes y conducta terapéutica. Pacientes y Métodos: Estudio descriptivo, retrospectivo, basado en la revisión de 16 historias clínicas de niños con lesiones focales hepáticas en el periodo comprendido entre enero 2007 a enero 2012. Se excluyeron los abscesos hepáticos. Resultados: El 68,75%11 eran del sexo masculino y 31,25%5 del sexo femenino; con edad promedio de 9,5 años (rango: 10 días - 14 años). Las lesiones focales benignas fueron: hemangioma 4/16 (25%), hematoma hepático 4/16 (25%), quiste hepático 3/16 (18,75%), hiperplasia nodular focal 1/16 (6,25%) adenoma 1/16 (6,25%) y las malignas: hepatocarcinoma 2/16 (12,50%) y hepatoblastoma 1/16 (6,25%). La mayoría de los pacientes (56,25%) se encontraban asintomáticos, 3/16 (18,75%) presentaron dolor abdominal, 3/16 (18,75%) masa palpable y 2/16 (12,5%) ictericia. La lesión fue identificada por ultrasonido abdominal en todos los pacientes y sólo el 56,25% (9/16) ameritaron tomografía con contraste. Al 43,75% (7/16) se les realizó marcadores tumorales y de estos el 42,85% (3/7) reportaron neoplasias. El funcionalismo hepático reportó normal en el 75% de los casos. Conclusión: El ultrasonido abdominal es el método de elección para el diagnóstico y seguimiento de las lesiones focales hepáticas, mientras el origen de las mismas, guía la conducta terapéutica. Abstract in english Introduction: focal liver lesions comprise a heterogeneous group of entities such as benign and malignant, solid or cysts, vascular, inflammatory masses and metastasis among others. Objective: To report focal liver lesions in children, clinical features, imaging and therapeutic behavior. Patients an [...] d Methods: A descriptive, retrospective study based on a review of 16 case histories of children with focal liver lesions in the period from January 2007 to January 2012. Liver abscesses were excluded. Results: 68.75%11 were male and 31.25%5 females, mean age 9.5 years (range: 10 days - 14 years). Focal lesions were benign: Hemangioma 4/16 (25%), liver hematoma 4/16 (25%), hepatic cyst 3/16 (18.75%), nodular focal hyperplasia 1/16 (6.25%) and adenomas 1/16 (6.25%) and malignant: Hepatocellular carcinoma 2/16 (12.50%) and hepatoblastoma 1/16 (6.25%). Most patients (56.25%) were asymptomatic, 3/16 (18.75%) had abdominal pain, 3/16 (18.75%) and palpable mass 2/16 (12.5%) jaundice. The lesion was identified by abdominal ultrasound in all patients and only 56.25% (9/16) needed tomography with contrast. To 43.75% (7/16) underwent tumor markers and of these 42.85% (3/7) reported neoplasm. Normal hepatic function reported in 75% of cases. Conclusion: An abdominal ultrasound is the method of choice for the diagnosis and management of focal liver lesions, while the origin of them, guide therapeutic conduct.

Adalis, Rossell; Dianora, Navarro; Karolina, López; Enicar, Perla; Betzabeth, Quintana; Credy, Figueredo; Andrea, Nogales; Katiuska, Belandria.

2013-06-01

140

Defect modelling  

International Nuclear Information System (INIS)

Calculations, drawing principally on developments at AERE Harwell, of the relaxation about lattice defects are reviewed with emphasis on the techniques required for such calculations. The principles of defect modelling are outlined and various programs developed for defect simulations are discussed. Particular calculations for metals, ionic crystals and oxides, are considered. (UK)

 
 
 
 
141

Fractures of the articular processes of the cervical spine  

International Nuclear Information System (INIS)

Fractures of the articular processes occurred in 16 (20.8%) of 77 patients with cervical spine fractures as demonstrated by multidirectional tomography. Plain films demonstrated the fractures in only two patients. Acute cervical radiculopathy occurred in five of the patients with articular process fractures (superior process, two cases; inferior process, three cases). Persistent neck pain occurred in one other patient without radiculopathy. Three patients suffered spinal cord damage at the time of injury, which was not the result of the articular process fracture itself. In the other seven cases, no definite sequelae occurred. However, disruption of the facet joint may predispose to early degenerative joint disease and chronic pain; unilateral or bilateral facet dislocation was present in five patients. In patients with cervical trauma who develop cervical radiculopathy, tomography should be performed to evaluate the articular processes

142

Biomechanical evaluation of suture-holding properties of native and tissue-engineered articular cartilage.  

Science.gov (United States)

The purpose of this study was to determine suture-holding properties of tissue-engineered neocartilage relative to native articular cartilage. To this end, suture pull-out strength was quantified for native articular cartilage and for neocartilages possessing various mechanical properties. Suture-holding properties were examined in vitro and in vivo. Neocartilage from bovine chondrocytes was engineered using two sets of exogenous stimuli, resulting in neotissue of different biochemical compositions. Compressive and tensile properties and glycosaminoglycan, collagen, and pyridinoline cross-link contents were assayed (study 1). Suture pull-out strength was compared between neocartilage constructs, and bovine and leporine native cartilage. Uniaxial pull-out test until failure was performed after passing 6-0 Vicryl through each tissue (study 2). Subsequently, neocartilage was implanted into a rabbit model to examine short-term suture-holding ability in vivo (study 3). Neocartilage glycosaminoglycan and collagen content per wet weight reached [Formula: see text] and [Formula: see text], respectively. Tensile properties for neocartilage constructs reached [Formula: see text] MPa for Young's modulus and [Formula: see text] MPa for ultimate tensile strength. Neocartilage reached [Formula: see text]33 % of suture pull-out strength of native articular cartilage. Neocartilage cross-link content reached 50 % of native values, and suture pull-out strength correlated positively with cross-link content [Formula: see text]. Neocartilage sutured into rabbit osteochondral defects was successfully maintained for 3 weeks. This study shows that pyridinoline cross-links in neocartilage may be vital in controlling suture pull-out strength. Neocartilage produced in vitro with one-third of native tissue pull-out strength appears sufficient for construct suturing and retention in vivo. PMID:24848644

DuRaine, G D; Arzi, B; Lee, J K; Lee, C A; Responte, D J; Hu, J C; Athanasiou, K A

2015-01-01

143

Focal rigidity of flat tori  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Dada uma variedade Riemanniana (M, g) fechada, isto é, compacta e sem bordo, existe uma partição de seu fibrado tangente TM = ?i?i chamada decomposição focal de TM. Os conjuntos ?i estão intimamente associados ao modo como focalizam as geodésicas de (M,g), isto é, à situação em que existem exatament [...] e i arcos de geodésica de mesmo comprimento unindo pontos p e q em M. Nesta nota, estudamos a estrutura topológica da decomposição focal de uma variedade Riemanniana fechada e sua relação com a estrutura métrica de M. Nosso principal resultado é que n-toros planos, n > 2, são focalmente rigidos, isto é, se dois toros planos são focalmente equivalentes, então os dois toros são isométricos módulo mudança de escala. O caso n = 2 foi considerado anteriormente por F. Kwakkel. Abstract in english Given a closed Riemannian manifold (M, g), i.e. compact and boundaryless, there is a partition of its tangent bundle TM = ?i?i called the focal decomposition of TM. The sets ?i are closely associated to focusing of geodesics of (M, g), i.e. to the situation where there are exactly i geodesic arcs of [...] the same length joining points p and q in M. In this note, we study the topological structure of the focal decomposition of a closed Riemannian manifold and its relation with the metric structure of the manifold. Our main result is that flat n-tori, n > 2, are focally rigid in the sense that if two flat tori are focally equivalent then the tori are isometric up to rescaling. The case n = 2 was considered before by F. Kwakkel.

Ferry, Kwakkel; Marco, Martens; Mauricio, Peixoto.

1149-11-01

144

Focal length and focal depth of metallic superlens  

Science.gov (United States)

We consider the problems of focal length and focal depth of subwavelength imaging via a silver slab of metallic superlens. The performance limit of the metallic superlens was associated with the losses in the metallic film. The transmittance through a metal film is quite low and decreases exponentially with the thickness of the metal film. In the visible wavelength region, the permittivity of Ag can be approximated by the Drude model, so it can be described as the plural permittivity. The real part ( ?' ) of permittivity of the metal slab has been preferably index matched to the host material, and the imaginary part ( ?'' ) is considered to prevent ideal reconstruction of the image. Because superlens are usually made of metals with significant intrinsic loss ( ?''>0 ), the image is blurred and it is regarded as an ultimate limitation to a near field perfect lens. The real part ( ?' )and the imaginary part ( ?'' ) of permittivity of the metal slab is the function of the incident wavelength, so we discuss the relationship of the focal length, focal depth and the incident wavelength. We also derive the expression for the resolution limit of metallic lens and demonstrate that the area of its subwavelength performance is usually limited to the near-field zone.

Cao, Pengfei; Cheng, Lin; Li, Ying; Zhang, Xiaoping; Kong, Weijie; Gong, Li; Zhao, Xining

2012-10-01

145

Purification of human articular proteoglycans and technical aspects of radioimmunoassay  

International Nuclear Information System (INIS)

Proteoglycans (PG) have been purified by classical methods from human articular cartilage in order to set up a radioimmunoassay. Conditions of labelling, purification of labelled PG, and optimal conditions of buffer, temperature, duration of incubations and dilution of antiserum are described. Separation of free and bound PG is performed by immunoprecipitation. It is demonstrated that human articular PG can be assayed quantitatively by RIA procedure, with a sensitivity of +- 2 femto-moles (+- 5 ng) per tube

146

Immunogenicity of Bovine and Leporine Articular Chondrocytes and Meniscus Cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Immune rejection is a major concern for any allogeneic or xenogeneic graft. For in vivo investigations of cartilage tissue engineering strategies, small animal models such as the leporine model are commonly employed. Many studies report little to no immune rejection upon allogeneic or xenogeneic implantation of native articular and meniscal cartilages. This study investigated whether bovine and leporine articular chondrocytes (ACs) and meniscus cells (MCs) have immunoprivileged characteristic...

Huey, Daniel J.; Sanchez-adams, Johannah; Willard, Vincent P.; Athanasiou, Kyriacos A.

2011-01-01

147

Morphologic Study of Posterior Articular Depression in Schatzker IV Fractures.  

Science.gov (United States)

The Schatzker classification of tibial plateau fractures is widely accepted. Type IV fractures are medial tibial plateau fractures that are either split off as a wedge fragment or depressed and comminuted. Posterior articular surface depression in Schatzker type IV tibial plateau fractures can be seen as a unique variant that increases the difficulty of reduction of the articular surface. Its morphologic characteristics have not been fully studied, and the incidence is sometimes underestimated. The goal of this study was to evaluate the morphologic characteristics of posterior articular depression in Schatzker type IV fractures based on computed tomography measurements. From January 2009 to December 2011, the medical records, including digital radiologic data, of all patients treated for tibial plateau fracture at the authors' institution were retrospectively analyzed. Articular surface depression deeper than 5 mm was the criterion for study inclusion. The depression depth, precise location of the articular depression center, surface area percentage, and distance of the fracture gap to the depression center were calculated. One hundred fifteen cases of Schatzker type IV fracture were retrieved, and a total of 47.83% (55 of 115) cases had posterior articular surface depression. The average depth of the depressed articular surface was 12.41 mm, the surface area percentage was 20.15% of the entire tibial plateau, and the gap distance from the medial direction was 41.40 mm, 2.8 times longer than that from the posterior direction, which was 14.91 mm. Posterior articular surface depression occurs in nearly half of Schatzker type IV fractures, and the posterior approach provides more direct access to the depression than the medial approach. [Orthopedics. 2015; 38(2):e124-e128.]. PMID:25665117

Zhai, Qilin; Hu, Chengfang; Xu, Yafeng; Wang, Dan; Luo, Congfeng

2015-02-01

148

Intra-articular Microparticles for Drug Delivery to the TMJ  

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This study describes the in vivo biocompatibility of intra-articular poly(DL-lactic-co-glycolic acid) (PLGA) microparticle (MP) formulations in the rat temporomandibular joint (TMJ). To our knowledge, this is the first intra-articular microparticle-based drug delivery system for the TMJ. The impact of PLGA MP concentration on rat TMJ function was quantified via computerized meal pattern analysis; in this non-invasive technique, previously validated markers of TMJ pain or nociception (specific...

Mountziaris, P. M.; Sing, D. C.; Mikos, A. G.; Kramer, P. R.

2010-01-01

149

Intra-articular Glucocorticoid Treatment : Efficacy and Side Effects  

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Intra-articular glucocorticoid injection therapy is frequently used to relieve symptoms of arthritis, but there is considerable variation in injection routines among physicians. One issue of debate concerns the importance of synovial fluid aspiration during the injection procedure. In the present randomised controlled study of patients with rheumatoid arthritis (RA), a significantly reduced risk for arthritis relapse was observed when arthrocentesis was included in the intra-articular injecti...

Weitoft, Tomas

2005-01-01

150

High-grade intra-articular liposarcoma of the knee.  

Science.gov (United States)

A high-grade pleomorphic intra-articular liposarcoma of the knee is described in a 48-year-old man, which was diagnosed histologically after arthroscopy of the knee for suspected pigmented villonodular synovitis (PVNS). The patient proceeded to undergo an extra-articular resection with a custom-made prosthesis. This report highlights the need to remember this rare tumour in the differential diagnosis of atypical soft tissue lesions within the knee joint prior to instrumentation. PMID:21174203

Shaerf, Daniel A; Mann, Bhupinder; Alorjani, Mohammed; Aston, Will; Saifuddin, Asif

2011-03-01

151

Articular cartilage mineralization in osteoarthritis of the hip  

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Abstract Background The aim of this study was to examine the frequency of articular cartilage calcification in patients with end-stage hip OA. Further, its impact on the clinical situation and the OA severity are analyzed. Methods Eighty patients with OA of the hip who consecutively underwent total hip replacement were prospectively evaluated, and 10 controls were included. The patients' X-rays were analyzed for the presence of articular cartilage mineralization...

Lohmann Christoph; Schäfer Fritz; Lammers Lydia; Niggemeyer Oliver; Fuerst Martin; Rüther Wolfgang

2009-01-01

152

Pendulum mass affects the measurement of articular friction coefficient.  

Science.gov (United States)

Friction measurements of articular cartilage are important to determine the relative tribologic contributions made by synovial fluid or cartilage, and to assess the efficacy of therapies for preventing the development of post-traumatic osteoarthritis. Stanton's equation is the most frequently used formula for estimating the whole joint friction coefficient (?) of an articular pendulum, and assumes pendulum energy loss through a mass-independent mechanism. This study examines if articular pendulum energy loss is indeed mass independent, and compares Stanton's model to an alternative model, which incorporates viscous damping, for calculating ?. Ten loads (25-100% body weight) were applied in a random order to an articular pendulum using the knees of adult male Hartley guinea pigs (n=4) as the fulcrum. Motion of the decaying pendulum was recorded and ? was estimated using two models: Stanton's equation, and an exponential decay function incorporating a viscous damping coefficient. ? estimates decreased as mass increased for both models. Exponential decay model fit error values were 82% less than the Stanton model. These results indicate that ? decreases with increasing mass, and that an exponential decay model provides a better fit for articular pendulum data at all mass values. In conclusion, inter-study comparisons of articular pendulum ? values should not be made without recognizing the loads used, as ? values are mass dependent. PMID:23122223

Akelman, Matthew R; Teeple, Erin; Machan, Jason T; Crisco, Joseph J; Jay, Gregory D; Fleming, Braden C

2013-02-01

153

Differential gene expression associated with postnatal equine articular cartilage maturation  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Articular cartilage undergoes an important maturation process from neonate to adult that is reflected by alterations in matrix protein organization and increased heterogeneity of chondrocyte morphology. In the horse, these changes are influenced by exercise during the first five months of postnatal life. Transcriptional profiling was used to evaluate changes in articular chondrocyte gene expression during postnatal growth and development. Methods Total RNA was isolated from the articular cartilage of neonatal (0–10 days and adult (4–5 years horses, subjected to one round of linear RNA amplification, and then applied to a 9,367-element equine-specific cDNA microarray. Comparisons were made with a dye-swap experimental design. Microarray results for selected genes (COL2A1, COMP, P4HA1, TGFB1, TGFBR3, TNC were validated by quantitative polymerase chain reaction (qPCR. Results Fifty-six probe sets, which represent 45 gene products, were up-regulated (p Conclusion Differential expression of genes encoding matrix proteins and matrix-modifying enzymes between neonates and adults reflect a cellular maturation process in articular chondrocytes. Up-regulated transcripts in neonatal cartilage are consistent with growth and expansion of the articular surface. Expression patterns in mature articular cartilage indicate a transition from growth to homeostasis, and tissue function related to withstanding shear and weight-bearing stresses.

Stromberg Arnold J

2008-11-01

154

Cervical spinal luxation in two dogs with entrapment of the cranial articular process of C6 over the caudal articular process of C5  

International Nuclear Information System (INIS)

In 2 Poodles, the cranial articular process of C6 was luxated and interlocked dorsal to the caudal articular process of C5. Surgical management in each case included reduction and stabilization of the articular processes, along with limited dorsal laminectomy. One of the dogs was completely normal 4 weeks after surgery, but the other had residual neurologic deficits 11 months after injury

155

Combined Effect of Subchondral Drilling and Hyaluronic Acid with/without Diacerein in Full-Thickness Articular Cartilage Lesion in Rabbits  

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The osteochondral healing potential of hyaluronic acid (HA) plus diacerein was evaluated in subchondral-drilling- (SCD-) induced fibrocartilage generation in rabbits. A full-thickness chondral defect was created along the patellar groove of both knees and then SCD was subsequently performed only in the left knee. A week later, the rabbits were allocated into 3 groups to receive weekly intra-articular (IA) injection for 5 weeks with normal saline solution (NSS) (group 1) or with HA (group 2 an...

Suwannaloet, Wanwisa; Laupattarakasem, Wiroon; Sukon, Peerapol; Ong-chai, Siriwan; Laupattarakasem, Pisamai

2012-01-01

156

Hydromechanical stimulator for chondrocyte-seeded constructs in articular cartilage tissue engineering applications.  

Science.gov (United States)

Mechanical stimulation is a key technique used for controlling the mechanical properties of tissue engineered articular cartilage constructs proposed for defect repair. The present study introduces a new technical method and device for 'hydromechanical' stimulation of tissue engineered articular cartilage constructs. The stimulation consists of simultaneous cyclic compression, frictional shear from a sliding indenter contact and direct pressurized fluid perfusion. Each of these modes of mechanical loading has been shown by other research groups to effectively stimulate tissue engineered constructs. A device for applying these conditions was designed, developed and tested. Two sets (high and low perfusion flow rates) of three experiments were performed, each with two samples subjected to hydromechanical stimulation conditions (compression and friction forces along with perfusion). Two other samples from each set were subjected to just compression and dynamic frictional shear forces, and two more were used as controls (not stimulated). The average amount of glycosaminoglycan retained in the constructs after 3 weeks ranked from low to high as follows: controls, hydromechanical conditions with the low-flow rate, hydromechanical conditions with the high-flow rate and just compression plus dynamic frictional shear. Statistically significant differences were not detected. However, future studies would focus on glycosaminoglycan production in the superficial zone, measuring the glycosaminoglycan released to the nutrient media, and address altering the hydromechanical stimulation parameters using the results of the present study as guidance, in attempts to achieve statistically significant increases in glycosaminoglycan production compared with the controls. PMID:23662347

Pourmohammadali, Homeyra; Chandrashekar, Naveen; Medley, John B

2013-03-01

157

Anticuerpo anticitrulina y manifestaciones extra articulares en artritis reumatoidea Anticitrulin antibody and the extra-articular manifestations in rheumatoid arthritis  

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Los pacientes con artritis reumatidea (AR) pueden desarrollar manifestaciones extra articulares (MExA), relacionadas a su morbi-mortalidad. Los anticuerpos anti-péptidos citrulinados cíclicos (ACCP) son específicos para la AR y estan relacionados con el daño articular; y podrían tener rol patogénico en las MExA. Nuestro objetivo fue determinar la relación entre los anticuerpos ACCP y MExA en pacientes con AR. Se incluyeron 74 pacientes con diagnóstico de AR (ACR 1987) mayores de 18 a?...

María Jezabel Haye Salinas; Soledad Retamozo; Lorena Vetorazzi; Natalia Peano; Patricia Ericka Díaz Cuiza; María Sol Castaños Menescardi; Evangelina María Miretti; Laura Mariela Encinas; Ana Cecilia Álvarez; Verónica Saurit; Alejandro Alvarellos; Francisco Caeiro

2013-01-01

158

Pathophysiology of focal segmental glomerulosclerosis  

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Focal segmental glomerulosclerosis (FSGS) is a major cause of idiopathic steroid-resistant nephrotic syndrome (SRNS) and end-stage kidney disease (ESKD). In recent years, animal models and studies of familial forms of nephrotic syndrome helped elucidate some mechanisms of podocyte injury and disease progression in FSGS. This article reviews some of the experimental and clinical data on the pathophysiology of FSGS.

Reidy, Kimberly; Kaskel, Frederick J.

2007-01-01

159

Nuclear medicine evaluation of focal fatty infiltration of the liver  

International Nuclear Information System (INIS)

Focal fatty infiltration of the liver (FFIL) occasionally may be mistaken as metastatic disease, primary liver malignancy, or other space-occupying lesions on CT or ultrasound studies, especially if there is significant mass effect. In these confusing cases, Xe-133 liver imaging has been advocated for confirmation of FFIL, since such studies have been reported to be sensitive and specific. The authors present results of four Xe-133 and four Tc-99m sulfur colloid scans in six patients with FFIL. Xe-133 imaging was found useful for diagnostic confirmation in only one patient and was misleading in the other three. Routine liver-spleen imaging was a more reliable method of confirmation, since no focal defects were found in any of the patients

160

Extracellular matrix of ostrich articular cartilage  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: English Abstract in english The composition and organization of the extracellular matrix of ostrich articular cartilage was investigated, using samples from the proximal and distal surfaces of the tarsometatarsus. For morphological analysis, sections were stained with toluidine blue and analyzed by polarized light microscopy. [...] For biochemical analysis, extracellular matrix components were extracted with 4 M guanidinium chloride, fractionated on DEAE-Sephacel and analyzed by SDS-PAGE. Glycosaminoglycans were analyzed by electrophoresis in agarose gels. Structural analysis showed that the fibrils were arranged in different directions, especially on the distal surface. The protein and glycosaminoglycan contents of this region were higher than in the other regions. SDS-PAGE showed the presence of proteins with molecular masses ranging from 17 to 121 kDa and polydisperse components of 67, 80-100, and 250-300 kDa in all regions. The analysis of glycosaminoglycans in agarosepropylene diamine gels revealed the presence of only chondroitin-sulfate. The electrophoretic band corresponding to putative decorin was a small proteoglycan containing chondroitin-sufate and not dermatan-sulfate, unlike other cartilages. The higher amounts of proteins and glycosaminoglycans and the multidirectional arrangement of fibrils seen in the distal region may be correlated with the higher compression normally exerted on this region.

Tatiana Carla, Tomiosso; Laurecir, Gomes; Benedicto, de Campos Vidal; Edson Rosa, Pimentel.

2005-04-01

 
 
 
 
161

Extracellular matrix of ostrich articular cartilage  

Directory of Open Access Journals (Sweden)

Full Text Available The composition and organization of the extracellular matrix of ostrich articular cartilage was investigated, using samples from the proximal and distal surfaces of the tarsometatarsus. For morphological analysis, sections were stained with toluidine blue and analyzed by polarized light microscopy. For biochemical analysis, extracellular matrix components were extracted with 4 M guanidinium chloride, fractionated on DEAE-Sephacel and analyzed by SDS-PAGE. Glycosaminoglycans were analyzed by electrophoresis in agarose gels. Structural analysis showed that the fibrils were arranged in different directions, especially on the distal surface. The protein and glycosaminoglycan contents of this region were higher than in the other regions. SDS-PAGE showed the presence of proteins with molecular masses ranging from 17 to 121 kDa and polydisperse components of 67, 80-100, and 250-300 kDa in all regions. The analysis of glycosaminoglycans in agarosepropylene diamine gels revealed the presence of only chondroitin-sulfate. The electrophoretic band corresponding to putative decorin was a small proteoglycan containing chondroitin-sufate and not dermatan-sulfate, unlike other cartilages. The higher amounts of proteins and glycosaminoglycans and the multidirectional arrangement of fibrils seen in the distal region may be correlated with the higher compression normally exerted on this region.

Tatiana Carla Tomiosso

2005-04-01

162

Defect detective  

International Nuclear Information System (INIS)

DEFECT DETECTIVE is an expert system computer program that is used by AECL to detect and evaluate fuel defects on the basis of data received from the four operating CANDU-600s. By applying the rules of data interpretation, the program evaluates the condition of the fuel defect in each suspect channel and recommends the removal priority. The recommendations are designed to minimize the costs associated with premature refuellings and the occupational exposures associated with the buildup of gamma radiation fields. These fields are due to depositing fission products that are released from some defects. Since both factors can have an impact on station economics, it is important to routinely analyze all available data that provides clues on the number, the condition, and the location of fuel defects. This expert system is intended to speed up routine analysis of fuel defect detection. It is written entirely in the PROLOG programming language which offers several advantages beyond expert system shells

163

Focal rhabdomyosarcomatous differentiation in primary liposarcoma.  

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A unique case of primary myxoid liposarcoma of the thigh, in which focal pleomorphic areas were present containing rhabdomyoblasts, is described. Focal rhabdomyosarcoma in liposarcoma has only rarely been reported previously and only in dedifferentiated liposarcomas of the retroperitoneum. All but one have been recurrences with rhabdomyoblasts being absent in the primary liposarcoma. As rhabdomyoblasts were only focally present, the present case is regarded as liposarcoma with focal divergent...

Shanks, J. H.; Banerjee, S. S.; Eyden, B. P.

1996-01-01

164

Extra-articular manifestations and complications of rheumatoid arthritis.  

Science.gov (United States)

Rheumatoid arthritis (RA) is a systemic inflammatory disease that can involve other tissues and organs as well as synovial joints. This chapter reviews the clinical aspects of extra-articular RA, from the early descriptions in rheumatology texts to reports from more recent cross-sectional and inception cohort studies. There is no agreed classification for these manifestations and, because criteria and definitions vary so much, this report includes not only the classic extra-articular features but also the non-articular complications of RA, for example normochromic normocytic anaemia and chronic leg ulcers, and the important disease-associated comorbidities, including non-Hodgkin's lymphoma, ischaemic heart disease and osteoporosis. Incidence and frequency figures for extra-articular RA vary according to study design. Nodules are the most common extra-articular feature, and are present in up to 30%; many of the other classic features occur in 1% or less in normal clinic settings. Sjögren's syndrome, anaemia of chronic disease and pulmonary manifestations are relatively common - in 6-10% - are frequently present in early disease and are all related to worse outcomes measures of rheumatoid disease, in particular functional impairment and mortality. Currently, there are no reliable predictors for these features in early RA, although they are associated with men, smokers, more severe joint disease, worse function, high levels of inflammatory markers, and the presence of rheumatoid factor (RF), antinuclear antibodies (ANA) and the RA HLA-related shared epitope. Many of these manifestations are related to the more active and severe RA, so early and more aggressive RA drug therapies are being employed and, although evidence from randomised studies is not available, this approach would seem appropriate in view of the adverse effect of extra-articular manifestations on RA outcomes. Unfortunately, specific therapies for extra-articular manifestations of RA are largely disappointing or unavailable, except for steroids and cyclophosphamide for vasculitis. The place for biological therapies is still not clear. Pulmonary fibrosis in RA has a poor prognosis whether treated with large doses of steroids, cytotoxic or disease modifying drugs like cyclosporine, or biologics. In summary, extra-articular features and non-articular complications of RA are common and are generally related to worse disease. They need to be recognised early and managed promptly. PMID:17870035

Young, Adam; Koduri, Gouri

2007-10-01

165

MRI of Focal Liver Lesions.  

Science.gov (United States)

Magnetic resonance imaging, MRI has more advantages than ultrasound, computed tomography, CT, positron emission tomography, PET, or any other imaging modality in diagnosing focal hepatic masses. With a combination of basic T1 and T2 weighted sequences, diffusion weighted imaging, DWI, and hepatobiliary gadolinium contrast agents, that is gadobenate dimeglumine (Gd-BOPTA) and gadoxetic acid (Gd-EOB), most liver lesions can be adequately diagnosed. Benign lesions, as cyst, hemangioma, focal nodular hyperplasia, FNH or adenoma, can be distinguished from malignant lesions. In a non-cirrhotic liver, the most common malignant lesions are metastases which may be hypovascular or hypervascular. In the cirrhotic liver hepatocellular carcinoma, HCC, is of considerable importance. Besides, intrahepatic cholangiocarcinoma and other less common malignancies has to be assessed. In this review, the techniques and typical MRI features are presented as well as the new algorithm issued by American Association for the Study of the Liver Diseases (AASLD). PMID:23049491

Albiin, Nils

2012-05-01

166

Determination of focal spot area  

International Nuclear Information System (INIS)

The paper summarizes the activities for standardization on the national and the international level. The measuring methods explained in the various standards are discussed with a view to applicability and information yield: Measurement of the MTF of focal spot is tedious but yields a maximum of information on the imaging characteristics. This technique therefore is the method of choice recommended in the new DIN/EC focal spot publications. Direct resolution measurement using the NEMA test bears the disadvantage of many error sources, and only limited information yield. It is, however, a technique that has gained most support in the USA, due to simplicity of instruments and rapid procedure. Another, novel concept, the RMS concept, is discussed as a candidate concept for standardization. (orig./DG)

167

Surface modified PLGA/carbon nanofiber composite enhances articular chondrocyte functions  

Science.gov (United States)

Since articular cartilage has a limited self regeneration capability, alternative methods are needed for repairing cartilage defects. The purpose of the present in vitro study was to explore the effects of material surface properties and external stimulation on chondrocyte (cartilage-synthesizing cell) functions. Based on this information, a goal of this research was to propose a scaffold composite material for enhancing articular chondrocyte function. To improve functions of chondrocytes, material (namely, poly(lactic-co-glycolic acid); PLGA) surfaces were modified via chemical (NaOH) etching techniques. Chondrocytes were cultured on surface-modified 2-D PLGA films and 3-D PLGA tissue engineering scaffolds, which were created by a salt-leaching method. Carbon nanofibers were imprinted on PLGA matrices in an aligned pattern for controlled electrically-active surface features. Electrical stimulation was applied to expedite and enhance chondrocyte functions. Results demonstrated that both NaOH-treated 2-D and 3-D substrates enhanced chondrocyte functions (cell numbers as well as extracellular matrix production) compared to non-treated PLGA substrates. Furthermore, chondrocytes preferred to attach along the carbon nanofiber patterns imprinted on PLGA. Electrical stimulation also enhanced chondrocyte functions on carbon nanofiber/PLGA composites. Underlying material properties that may have enhanced chondrocyte functions include a more hydrophilic surface, surface energy differences due to the presence of carbon nanofibers, increased surface area, altered porosity, and a greater degree of nanometer roughness. Moreover, these altered surface properties positively influenced select protein adsorption that controlled subsequent chondrocyte adhesion. Collectively, this study provided a scaffold model for osteochondral defects that can be synthesized using the above techniques and a layer by layer approach to accommodate the property differences in each layer of natural cartilage. Specifically, these results suggest that the superficial zone, middle zone, and deep zone of cartilage should be composed of carbon nanofibers aligned parallel to the surface in PLGA, randomly oriented carbon nanofibers in PLGA, and carbon nanofibers aligned perpendicular to the surface in PLGA, respectively. Clearly, such scaffolds may ultimately enhance the efficacy of scaffolds used for articular cartilage repair.

Park, Grace Eunseung

168

PATHOGENESIS AND THERAPY OF FOCAL SEGMENTAL GLOMERULOSCLEROSIS: AN UPDATE  

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Focal and segmental glomerulosclerosis (FSGS) is an important cause of steroid resistant nephrotic syndrome in adults and children. It is responsible for 5–20% of all cases of end-stage kidney disease (ESKD) in the United States. The pathogenesis of FSGS has not been fully elucidated; however data from molecular studies of familial cases in the last two decades suggest that FSGS is a defect of the podocyte. The therapeutic agents available for treatment of FSGS are not very effective and on...

Gbadegesin, Rasheed; Lavin, Peter; Foreman, John; Winn, Michelle

2010-01-01

169

Genetics of focal segmental glomerulosclerosis  

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The recent advances in understanding the pathophysiology of focal segmental glomerulosclerosis (FSGS) and molecular function of glomerular filtration barrier come directly from genetic linkage and positional cloning studies. The exact role and function of the newly discovered genes and proteins are being investigated by in vitro and in vivo mechanistic studies. Those genes and proteins interactions seem to change susceptibility to kidney disease progression. Better understanding of their exac...

Woroniecki, Robert P.; Kopp, Jeffrey B.

2007-01-01

170

Acute insulin responses to calcium and tolbutamide do not differentiate focal from diffuse congenital hyperinsulinism.  

Science.gov (United States)

Congenital hyperinsulinism (CHI) is related to two main histological pancreas anomalies: focal adenomatous hyperplasia and diffuse beta-cell hypersecretion. Pharmacological tests to measure acute insulin responses (AIR) to peripheral i.v. injections of glucose, calcium, and tolbutamide have been reported as potential means to distinguish between these histological forms. In patients with defects in ATP-sensitive potassium channels, tolbutamide will fail to induce insulin release in affected portions of the pancreas, whereas calcium gluconate will enhance insulin release through spontaneously active voltage-gated Ca(2+) channels. Consequently, in focal CHI patients, calcium should promote AIRs from the lesion, whereas tolbutamide should act to promote insulin secretion from the healthy region of the pancreas (outside the focal hyperplasia). We therefore studied AIRs to calcium and tolbutamide stimulation tests in 16 children with focal (n = 9) or diffuse (n = 7) CHI before pancreatic surgery. We found hypervariable AIRs to glucose and calcium stimulation in both focal and diffuse CHI patients. AIRs to tolbutamide stimulation were found modest in focal CHI patients, which might account for beta-cell quiescence in the healthy portion of the pancreas of these patients. We conclude that AIRs to calcium and tolbutamide stimulation tests are not sufficient to differentiate the focal from the diffuse CHI patients. PMID:14764815

Giurgea, Irina; Laborde, Kathleen; Touati, Guy; Bellanné-Chantelot, Christine; Nassogne, Marie-Cecile; Sempoux, Christine; Jaubert, Francis; Khoa, Nguyen; Chigot, Valerie; Rahier, Jacques; Brunelle, Francis; Nihoul-Fékété, Claire; Dunne, Mark J; Stanley, Charles; Saudubray, Jean-Marie; Robert, Jean-Jacques; de Lonlay, Pascale

2004-02-01

171

Usefulness of bone scintigraphy for detecting loosening of articular prostheses  

International Nuclear Information System (INIS)

The most important complication of articular substitution is the loosening of the prostheses as a result of permanent overstraining, trauma, chemical or infectious noxae. The value of bone scintigraphy in the diagnosis of loosening of the endoprothesis was examined in 53 articular prostheses (49 hip joints and 4 knee joints). A pathological scan was evident in all cases where the prosthesis had become loose (18 cases). whereas a normal scan was found in 34 firmly positioned prostheses. A false positive scan occured in one case of periarthritis. Bone scintigraphy can be employed as a means of diagnosing loosening of prostheses after a period of nine months following the operation; up to that time, enhancement can be due to the operation. A positive scan in case of loosening of the prosthesis is manifested earlier than radiological signs. For this reason, scintigraphy can be recommended as a routine examination method in pain after articular substitution surgery. (orig.)

172

Characterization of Chondrocyte Scaffold Carriers for Cell-based Gene Therapy in Articular Cartilage Repair  

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Articular cartilage lesions in the knee are common injuries. Chondrocyte transplant represents a promising therapeutic modality for articular cartilage injuries. Here, we characterize the viability and transgene expression of articular chondrocytes cultured in 3-D scaffolds provided by four types of carriers. Articular chondrocytes are isolated from rabbit knees and cultured in four types of scaffolds: type I collagen sponge, fibrin glue, hyaluronan, and Open-cell PolyLactic Acid (OPLA). The ...

Shui, Wei; Yin, Liangjun; Luo, Jeffrey; Li, Ruidong; Zhang, Wenwen; Zhang, Jiye; Huang, Wei; Hu, Ning; Liang, Xi; Deng, Zhong-liang; Hu, Zhenming; Shi, Lewis; Luu, Hue H.; Haydon, Rex C.; He, Tong-chuan

2013-01-01

173

Focal and multifocal diabetic neuropathies Neuropatia diabética focal e multifocal  

Directory of Open Access Journals (Sweden)

Full Text Available Diabetic neuropathy is the most common neuropathy in industrialized countries, with a remarkable range of clinical manifestations. The vast majority of the patients with clinical diabetic neuropathy have a distal symmetrical form that progress following a fiber-length dependent pattern, with predominant sensory and autonomic manifestations. This pattern of neuropathy is associated with a progressive distal axonopathy. Patients are exposed to trophic changes in the feet, pains and autonomic disturbances. Less often, diabetic patients may develop focal and multifocal neuropathy that includes cranial nerve involvement, limb and truncal neuropathies. This neuropathic pattern tends to occur after 50 years of age, mostly in patients with longstanding diabetes mellitus. The LDDP does not show any trend to improvement and either relentlessly progresses or remain relatively stable over years. Conversely the focal diabetic neuropathies, which are often associated with inflammatory vasculopathy on nerve biopsies, remain self limited, sometimes after a relapsing course.A neuropatia diabética é a mais predominante das neuropatias nos países industrializados apresentando uma gama variável de manifestações clinicas. A maioria dos pacientes com neuropatia diabética apresenta uma forma simétrica distal que progride para um padrão fibra comprimento dependente com manifestações sensitivas e autonomicas. Este tipo de neuropatia é associado com uma axonopatia distal progressiva. Os pacientes apresentam modificações tróficas nos pés, dores e distúrbios autonômicos. Menos freqüentemente os pacientes diabéticos podem desenvolver neuropatia focal e multifocal que incluem envolvimento de nervos cranianos, tronco e membros inferiores. Este padrão de neuropatia é mais freqüente em pacientes com mais de 50 anos e com longa historia de diabetes. Este tipo de neuropatia fibra-comprimento dependente não apresenta melhora, progride lentamente ou permanece estável por vários anos. As neuropatias focais que são associadas freqüentemente com vasculopatias inflamatórias nas biópsias de nervo, permanecem auto limitadas por vezes com surtos de remissão.

Gérard Said

2007-12-01

174

Focal and multifocal diabetic neuropathies / Neuropatia diabética focal e multifocal  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese A neuropatia diabética é a mais predominante das neuropatias nos países industrializados apresentando uma gama variável de manifestações clinicas. A maioria dos pacientes com neuropatia diabética apresenta uma forma simétrica distal que progride para um padrão fibra comprimento dependente com manife [...] stações sensitivas e autonomicas. Este tipo de neuropatia é associado com uma axonopatia distal progressiva. Os pacientes apresentam modificações tróficas nos pés, dores e distúrbios autonômicos. Menos freqüentemente os pacientes diabéticos podem desenvolver neuropatia focal e multifocal que incluem envolvimento de nervos cranianos, tronco e membros inferiores. Este padrão de neuropatia é mais freqüente em pacientes com mais de 50 anos e com longa historia de diabetes. Este tipo de neuropatia fibra-comprimento dependente não apresenta melhora, progride lentamente ou permanece estável por vários anos. As neuropatias focais que são associadas freqüentemente com vasculopatias inflamatórias nas biópsias de nervo, permanecem auto limitadas por vezes com surtos de remissão. Abstract in english Diabetic neuropathy is the most common neuropathy in industrialized countries, with a remarkable range of clinical manifestations. The vast majority of the patients with clinical diabetic neuropathy have a distal symmetrical form that progress following a fiber-length dependent pattern, with predomi [...] nant sensory and autonomic manifestations. This pattern of neuropathy is associated with a progressive distal axonopathy. Patients are exposed to trophic changes in the feet, pains and autonomic disturbances. Less often, diabetic patients may develop focal and multifocal neuropathy that includes cranial nerve involvement, limb and truncal neuropathies. This neuropathic pattern tends to occur after 50 years of age, mostly in patients with longstanding diabetes mellitus. The LDDP does not show any trend to improvement and either relentlessly progresses or remain relatively stable over years. Conversely the focal diabetic neuropathies, which are often associated with inflammatory vasculopathy on nerve biopsies, remain self limited, sometimes after a relapsing course.

Gérard, Said.

1272-12-01

175

Atualização em infecções em próteses articulares Update on infections in articular prosthesis  

Directory of Open Access Journals (Sweden)

Full Text Available O implante de próteses articulares, principalmente de quadril e joelho, vem se tornando cada vez mais frequente, representando significante redução no desconforto e imensurável melhora na mobilidade dos pacientes. As revisões da literatura mundial revelam que 1 a 5% destas próteses tornam-se infectadas, sendo importante lembrar que, conforme cresce o número de cirurgias para implantação destas próteses, cresce também o número de casos deste tipo de infecção. As bactérias gram-positivas são predominantes nas contaminações das próteses articulares, em especial o Staphylococcus aureus e o Staphylococcus epidermidis. As infecções causadas por bacilos gram-negativos e fungos como Candida sp vêm sendo relatadas com maior frequência em todo o mundo. As infecções de próteses articulares apresentam sinais característicos que podem ser divididos em manifestações agudas (dor severa, febre alta, toxemia, calor, rubor e secreção na ferida operatória e crônicas (dor progressiva, formação de fístulas cutâneas, com drenagem de secreção purulenta, sem febre. O diagnóstico definitivo da infecção deve ser realizado através do isolamento em cultura do micro-organismo obtido a partir da punção do líquido articular, secreção da ferida cirúrgica e materiais colhidos durante desbridamento cirúrgico. É fundamental a cobertura de S.aureus meticilino-resistente, visto a importância epidemiológica deste agente nessas infecções. O tempo total da antibioticoterapia varia de seis semanas a seis meses, sendo que o tratamento deve ser readequado quando necessário, com base nos resultados das culturas colhidas.The implantation of artificial joints, especially the hip and knee, is becoming increasingly common, representing a significant reduction in discomfort and an immeasurable improvement in patient mobility. Reviews of the global literature indicate that 1-5% of these grafts become infected, though it is important to remember that, as the number of surgeries for implantation of these prosthesis grows, so will the number of cases of this type of infection. Gram-positive bacteria predominate in the contamination of joint prosthesis, in particular Staphylococcus aureus and Staphylococcus epidermidis. Infections caused by gram-negative bacilli and fungi such as Candida sp have been reported with increased frequency throughout the world. Infections of joint prosthesis have characteristic signals that can be divided into acute (severe pain, high fever, toxemia, heat, redness, and wound secretion and chronic (progressive pain, cutaneous fistula formation, with pus drainage, no fever manifestations. The definitive diagnosis of the infection should be made through the isolation in culture of the micro-organism obtained from the puncture of the joint fluid, surgical wound secretion, and material collected during surgical debridement. It is essential to cover methicillin-resistant Staphylococcus aureus, given the epidemiological importance of this agent in these infections. The total time of antibiotic therapy varies from six weeks to six months, and that treatment should be adjusted as needed, based on the results of culturing.

Ana Lucia Lei Munhoz Lima

2010-01-01

176

Atualização em infecções em próteses articulares / Update on infections in articular prosthesis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O implante de próteses articulares, principalmente de quadril e joelho, vem se tornando cada vez mais frequente, representando significante redução no desconforto e imensurável melhora na mobilidade dos pacientes. As revisões da literatura mundial revelam que 1 a 5% destas próteses tornam-se infecta [...] das, sendo importante lembrar que, conforme cresce o número de cirurgias para implantação destas próteses, cresce também o número de casos deste tipo de infecção. As bactérias gram-positivas são predominantes nas contaminações das próteses articulares, em especial o Staphylococcus aureus e o Staphylococcus epidermidis. As infecções causadas por bacilos gram-negativos e fungos como Candida sp vêm sendo relatadas com maior frequência em todo o mundo. As infecções de próteses articulares apresentam sinais característicos que podem ser divididos em manifestações agudas (dor severa, febre alta, toxemia, calor, rubor e secreção na ferida operatória) e crônicas (dor progressiva, formação de fístulas cutâneas, com drenagem de secreção purulenta, sem febre). O diagnóstico definitivo da infecção deve ser realizado através do isolamento em cultura do micro-organismo obtido a partir da punção do líquido articular, secreção da ferida cirúrgica e materiais colhidos durante desbridamento cirúrgico. É fundamental a cobertura de S.aureus meticilino-resistente, visto a importância epidemiológica deste agente nessas infecções. O tempo total da antibioticoterapia varia de seis semanas a seis meses, sendo que o tratamento deve ser readequado quando necessário, com base nos resultados das culturas colhidas. Abstract in english The implantation of artificial joints, especially the hip and knee, is becoming increasingly common, representing a significant reduction in discomfort and an immeasurable improvement in patient mobility. Reviews of the global literature indicate that 1-5% of these grafts become infected, though it [...] is important to remember that, as the number of surgeries for implantation of these prosthesis grows, so will the number of cases of this type of infection. Gram-positive bacteria predominate in the contamination of joint prosthesis, in particular Staphylococcus aureus and Staphylococcus epidermidis. Infections caused by gram-negative bacilli and fungi such as Candida sp have been reported with increased frequency throughout the world. Infections of joint prosthesis have characteristic signals that can be divided into acute (severe pain, high fever, toxemia, heat, redness, and wound secretion) and chronic (progressive pain, cutaneous fistula formation, with pus drainage, no fever) manifestations. The definitive diagnosis of the infection should be made through the isolation in culture of the micro-organism obtained from the puncture of the joint fluid, surgical wound secretion, and material collected during surgical debridement. It is essential to cover methicillin-resistant Staphylococcus aureus, given the epidemiological importance of this agent in these infections. The total time of antibiotic therapy varies from six weeks to six months, and that treatment should be adjusted as needed, based on the results of culturing.

Ana Lucia Lei Munhoz, Lima; Priscila Rosalba Domingos de, Oliveira.

177

Imaging diagnosis of the juxta-articular bone cyst  

International Nuclear Information System (INIS)

Objective: To investigate the imaging features of the juxta-articular bone cyst(intra- osseous ganglia). Methods: The imaging findings of 54 cases histopathologically confirmed were studied retrospectively. X-ray, CT, and MRI were performed in 46 eases, 30 cases, and 14 cases, respectively. Results: Of the 54 cases, 27 arised from the ankle (including multiple lesions), 16 from the knee joint, 7 from the hip joint, 1 from the proximate end of the humerus, ulna, trapezium bone, the first phalange in each, and 1 from the talus and the distal end of the tibia. There were 43 cases (44 lesions) in the ankle and knee joints, with 29 (65.9%) lesions located in the medial articular surface. Fifty-four cases had thinning sclerotic rim, showing a unilocular round osteolytic appearance in 44 cases and a multiloculated-cystic appearance with septa in 10 cases. Discontinuous articular surface were seen in 15 cases, reticular surface collapse in 1, gas density in 3 and fluid-fluid plane in 1. (1) On x-ray films, 46 cases (47 lesions) with well-defined sclerotic rim revealed round, arch or irregular lyric areas at the adjacent articular surface. The fissures were found at the adjacent articular surface in 6 lesions. No joint spaces were abnormal. (2)On CT, 30 cases with sclerotic rim showed round in 19 lesions, arch in 3, and irregular in 8. The fissures were seen at the adjacent articular surface in 14 lesions. The density showed homogeneous in 27 lesions, and gas existed in 3. (3)s in 27 lesions, and gas existed in 3. (3) Fourteen cases (15 lesions)showed hypointense to isointense signal on MR T1WI and hyperintense signal on T2WI. Fluid-fluid plane was found in 1 case. The fissures were observed at the adjacent articular surface in 8 lesions. 7 cases showed swelling soft tissue. Conclusion: The characteristic locations combined with the typical imaging features may suggest the diagnosis of jaxta-articular bone cyst. (authors)

178

Evaluation of grades 3 and 4 chondromalacia of the knee using T2*-weighted 3D gradient-echo articular cartilage imaging  

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Objective. To determine the accuracy of T2*-weighted three-dimensional (3D) gradient-echo articular cartilage imaging in the identification of grades 3 and 4 chondromalacia of the knee.Design and patients. A retrospective evaluation of 80 patients who underwent both arthroscopic and MRI evaluation was performed. The 3D images were interpreted by one observer without knowledge of the surgical results. The medial and lateral femoral condyles, the medial and lateral tibial plateau, the patellar cartilage and trochlear groove were evaluated. MR cartilage images were considered positive if focal reduction of cartilage thickness was present (grade 3 chondromalacia) or if complete loss of cartilage was present (grade 4 chondromalacia). Comparison of the 3D MR results with the arthroscopic findings was performed.Results. Eighty patients were included in the study group. A total of 480 articular cartilage sites were evaluated with MRI and arthroscopy. Results of MR identification of grades 3 and 4 chondromalacia, all sites combined, were: sensitivity 83%, specificity 97%, false negative rate 17%, false positive rate 3%, positive predictive value 87%, negative predictive value 95%, overall accuracy 93%.Conclusion. The results demonstrate that T2*-weighted 3D gradient-echo articular cartilage imaging can identify grades 3 and 4 chondromalacia of the knee. (orig.)

Murphy, B.J. [Dept. of Radiology, Univ. of Miami School of Medicine, FL (United States)

2001-06-01

179

Evaluation of grades 3 and 4 chondromalacia of the knee using T2*-weighted 3D gradient-echo articular cartilage imaging  

International Nuclear Information System (INIS)

Objective. To determine the accuracy of T2*-weighted three-dimensional (3D) gradient-echo articular cartilage imaging in the identification of grades 3 and 4 chondromalacia of the knee.Design and patients. A retrospective evaluation of 80 patients who underwent both arthroscopic and MRI evaluation was performed. The 3D images were interpreted by one observer without knowledge of the surgical results. The medial and lateral femoral condyles, the medial and lateral tibial plateau, the patellar cartilage and trochlear groove were evaluated. MR cartilage images were considered positive if focal reduction of cartilage thickness was present (grade 3 chondromalacia) or if complete loss of cartilage was present (grade 4 chondromalacia). Comparison of the 3D MR results with the arthroscopic findings was performed.Results. Eighty patients were included in the study group. A total of 480 articular cartilage sites were evaluated with MRI and arthroscopy. Results of MR identification of grades 3 and 4 chondromalacia, all sites combined, were: sensitivity 83%, specificity 97%, false negative rate 17%, false positive rate 3%, positive predictive value 87%, negative predictive value 95%, overall accuracy 93%.Conclusion. The results demonstrate that T2*-weighted 3D gradient-echo articular cartilage imaging can identify grades 3 and 4 chondromalacia of the knee. (orig.)

180

Bigenic mouse models of focal segmental glomerulosclerosis involving pairwise interaction of CD2AP, Fyn, and synaptopodin  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Focal segmental glomerulosclerosis (FSGS) is the most common primary glomerular diagnosis resulting in end-stage renal disease. Defects in several podocyte proteins have been implicated in the etiology of FSGS, including podocin, ?-actinin–4, CD2-associated protein (CD2AP), and TRPC6. Despite our growing understanding of genes involved in the pathogenesis of focal segmental sclerosis, the vast majority of patients with this disease, even those with a familial linkage, lack a clear genetic ...

Huber, Tobias B.; Kwoh, Christopher; Wu, Hui; Asanuma, Katsuhiko; Go?del, Markus; Hartleben, Bjo?rn; Blumer, Ken J.; Miner, Jeffrey H.; Mundel, Peter; Shaw, Andrey S.

2006-01-01

 
 
 
 
181

Atypical Findings of Focal Nodular Hyperplasia with Gadoxetic Acid (Gd-EOB-DTPA)-Enhanced Magnetic Resonance Imaging.  

Science.gov (United States)

We report two cases of focal nodular hyperplasia in patients following gadoxetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging confirmed with histopathology. These cases showed an atypical pattern during the delayed-hepatobiliary phase after the injection of gadoxetic acid. One case showed a total defect, and the other showed a peripheral ring-like enhancement without a visible central scar, mimicking hepatocellular carcinoma. The pathologic examination demonstrated that the two lesions were focal nodular hyperplasia. PMID:24693305

Yoon, Jung-Hee; Kim, Ji-Yeon

2014-01-01

182

Antennas for bolometric focal plane  

International Nuclear Information System (INIS)

The future Cosmic Microwave Background (CMB) experiments will require large focal planes with hundreds of bolometric receivers. For CMB detectors, the field of view should be restricted, as even with cryostat cooled liquid helium temperatures a significant deteriorating performance load will be present (Appl. Opt. 41 (2002) 6543). We present a planar antenna for millimeter band produced by lithographical methods only, which, without lens concentrator or a horn, has convenient beamwidth about F/3-F/4. The radiation and impedance characteristics of the antenna were obtained from a moment-method calculation. The measured beammap of the antenna prototype is presented in this paper

183

Focal nodular hyperplasia: imaging findings  

Energy Technology Data Exchange (ETDEWEB)

Focal nodular hyperplasia is an uncommon benign hepatic tumor that continues to pose diagnostic dilemmas. Imaging techniques are of great value in diagnosis of this tumor. In this article we present the US, CT, MR imaging, scintigraphy, and angiography findings. The demonstration of a central vascular scar is very helpful. Although the radiologic features may be diagnostic, many atypical cases must be differentiated from other benign or malignant hepatic tumors. In these cases excisional biopsy and histopathologic examination are necessary to determine a definite diagnosis. (orig.)

Kehagias, D.; Moulopoulos, L.; Antoniou, A.; Hatziioannou, A.; Smyrniotis, V.; Trakadas, S.; Lahanis, S.; Vlahos, L. [Dept. of Radiology, University of Athens (Greece)

2001-02-01

184

Focal nodular hyperplasia: imaging findings  

International Nuclear Information System (INIS)

Focal nodular hyperplasia is an uncommon benign hepatic tumor that continues to pose diagnostic dilemmas. Imaging techniques are of great value in diagnosis of this tumor. In this article we present the US, CT, MR imaging, scintigraphy, and angiography findings. The demonstration of a central vascular scar is very helpful. Although the radiologic features may be diagnostic, many atypical cases must be differentiated from other benign or malignant hepatic tumors. In these cases excisional biopsy and histopathologic examination are necessary to determine a definite diagnosis. (orig.)

185

SNAP Satellite Focal Plane Development  

International Nuclear Information System (INIS)

The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square degree field in the visible and near-infrared wavelength regime. The requirements for the instrument suite and the present configuration of the focal plane concept are presented. A two year R and D phase, largely supported by the Department of Energy, is just beginning. We describe the development activities that are taking place to advance our preparedness for mission proposal in the areas of detectors and electronics

186

Cervical spinal luxation in two dogs with entrapment of the cranial articular process of C6 over the caudal articular process of C5.  

Science.gov (United States)

In 2 Poodles, the cranial articular process of C6 was luxated and interlocked dorsal to the caudal articular process of C5. Surgical management in each case included reduction and stabilization of the articular processes, along with limited dorsal laminectomy. One of the dogs was completely normal 4 weeks after surgery, but the other had residual neurologic deficits 11 months after injury. PMID:3710877

Basinger, R R; Bjorling, D E; Chambers, J N

1986-04-15

187

Focal Plane Instrumentation of VERITAS  

Science.gov (United States)

VERITAS is a new atmospheric Cherenkov imaging telescope array to detect very high energy gamma rays above 100 GeV. The array is located in southern Arizona, USA, at an altitude of 1270m above see level. The array currently consists of four 12 m telescopes, structurally resembling the Davis-Cotton design of the Whipple 10 m telescope. The VERITAS focal plane instruments are equipped with high-resolution (499 pixels) fast photo-multiplier-tube (PMT) cameras covering a 3.5 degree field of view with 0.148 degree pixel separation. Light concentrators reduce the dead-space between PMTs to 25% and shield the PMTs from ambient light. The PMTs are connected to high-speed pre-amplifiers improving the signal to noise ratio and allow single photoelectron measurements in situ at operating voltage. Current monitor circuits in the focus box provide real-time monitoring of the anode currents for each pixel and ambient conditions of the focus box. A charge injection system installed in the focus box allows daytime testing of the trigger and data acquisition system by injecting pulses of variable amplitude and length into pre-amplifier stage. A detailed description of the VERITAS focal plane instruments will be given in this presentation.

Nagai, T.; McKay, R.; Sleege, G.; et al.

188

Intra-articular injection of the acromioclavicular joint.  

Science.gov (United States)

Intra-articular punctures and injections are performed routinely on patients with injuries to and chronic diseases of joints, to release an effusion or haemarthrosis, or to inject drugs. The purpose of this study was to investigate the accuracy of placement of the needle during this procedure. A total of 76 cadaver acromioclavicular joints were injected with a solution containing methyl blue and subsequently dissected to distinguish intra- from peri-articular injection. In order to assess the importance of experience in achieving accurate placement, half of the injections were performed by an inexperienced resident and half by a skilled specialist. The specialist injected a further 20 cadaver acromioclavicular joints with the aid of an image intensifier. The overall frequency of peri-articular injection was much higher than expected at 43% (33 of 76) overall, with 42% (16 of 38) by the specialist and 45% (17 of 38) by the resident. The specialist entered the joint in all 20 cases when using the image intensifier. Correct positioning of the needle in the joint should be facilitated by fluoroscopy, thereby guaranteeing an intra-articular injection. PMID:19949131

Pichler, W; Weinberg, A M; Grechenig, S; Tesch, N P; Heidari, N; Grechenig, W

2009-12-01

189

Intra-articular Placement of an Intraosseous Catheter.  

Science.gov (United States)

Gaining vascular access is essential in the resuscitation of critically ill patients. Intraosseous (IO) placement is a fundamentally important alternative to intravenous (IV) access in conditions where IV access delays resuscitation or is not possible. This case report presents a previously unreported example of prehospital misplacement of an IO catheter into the intra-articular space of the knee joint. This report serves to inform civilian and military first responders, as well as emergency medicine physicians, of intra-articular IO line placement as a potential complication of IO vascular access. Infusion of large amounts of fluid into the joint space could damage the joint and be catastrophic to a patient who needs immediate IV fluids or medications. In addition, intra-articular IO placement could result in septic arthritis of the knee. Grabel Z , DePasse JM , Lareau CR , Born CT , Daniels AH . Intra-articular placement of an intraosseous catheter. Prehosp Disaster Med. 2015;30(1):1-4 . PMID:25483729

Grabel, Zachary; DePasse, J Mason; Lareau, Craig R; Born, Christopher T; Daniels, Alan H

2014-12-01

190

The Effectiveness of Ultrasound-Guided Steroid Injection for Femoroacetabular Impingement: A Comparison between the Extra-Articular and Intra-Articular Approaches  

International Nuclear Information System (INIS)

To assess the effectiveness of pain control using ultrasound-guided steroid injection by the extra-articular and intra-articular approaches to femoroacetabular impingement patients. From September through December 2010, 18 patients with clinical suspicion of femoroacetabular impingement syndrome underwent ultrasound-guided steroid and local anesthetics injection: a total of 20 cases, including 16 cases of ipsilateral and 2 cases of bilateral injection. Extra-articular or intra-articular approach was selected for each patient, randomly and alternately. Nine cases were performed by extra-articular approach and 11 cases were performed by intra-articular approach. Every patient was observed in the outpatient clinic and visual analogue scale (VAS) was taken and compared before and after the procedure in all patients. Pre-injection average VAS value of extra-articular approached cases was 5.22 ± 1.99 and post-injection average VAS value was 4.11 ± 1.96, which is statistically insignificant (p < 0.156). The average VAS value of intra-articular approached cases was decreased from 5.72 ± 2.15 to 2.91 ± 2.30 after injection, which is statistically significant (p < 0.006). Ultrasound guided intra-articular approached steroid and local anesthetics injection could be effective in controlling pain for patients with femoroacetabular impingement syndrome.

191

Periodontitis in patients with focal tuberculosis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The research goal is to investigate the mechanisms of formation and peculiarities of periodontitis in patients with focal tuberculosis. Patients with periodontitis and focal tuberculosis are proved to develop local inflammatory reaction with increased infection and activation of proinflammatory cytokines in parodontal pockets fluid. The main risk factor of frequent and durable recurrence of parodontal pathology in case of focal tuberculosis was the development of pathologic process as a cause...

Alexandrova ?.?.; Lepilin A.V.; Kazimirova N.E.; Shuldyakov ?.?.

2010-01-01

192

Periodontitis in patients with focal tuberculosis  

Directory of Open Access Journals (Sweden)

Full Text Available The research goal is to investigate the mechanisms of formation and peculiarities of periodontitis in patients with focal tuberculosis. Patients with periodontitis and focal tuberculosis are proved to develop local inflammatory reaction with increased infection and activation of proinflammatory cytokines in parodontal pockets fluid. The main risk factor of frequent and durable recurrence of parodontal pathology in case of focal tuberculosis was the development of pathologic process as a cause of disbalance of lipid peroxidation and antioxidant system, endotoxicosis syndrome

Alexandrova ?.?.

2010-12-01

193

Focal symmetrical encephalomalacia in sheep / Encefalomalacia focal simétrica em ovino  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Encefalomalacia focal simétrica (EFS) é a lesão mais proeminente vista nas formas subaguda ou crônica da enterotoxemia por Clostridium perfringens tipo D. Este trabalho relata EFS em ovinos no semiárido do estado da Paraíba. Seis ovinos morreram, em um período de sete dias, dentro de um rebanho de 7 [...] 0 animais, da raça Santa Inês, entre 4-30 meses de idade, que pastavam em piquete de Cynodon dactylon (capim Tifton), que estava rebrotando. Os ovinos eram suplementados com um concentrado de soja, trigo e milho. Os sinais nervosos incluíam cegueira e decúbito lateral. Um ovino de 19 meses de idade foi examinado clinicamente e necropsiado, depois de um curso clínico de 3 dias. Macroscopicamente foram observadas herniação do cerebelo e áreas acastanhadas, multifocais, simétricas e bilaterais na cápsula interna, tálamo e pedúnculo cerebelar. Histologicamente observou-se malacia, bilateral e simétrica, com alguns neutrófilos, tumefação das células endoteliais dos vasos sanguíneos, edema perivascular e hemorragia. O rebanho foi vacinado, antes do surto, com umaúnica dose de vacina para Clostridium perfringens tipo D. Dois fatores são sugestivos quanto a importância da ocorrência da enfermidade: imunidade insuficiente devida à vacinação incorreta; e altos níveis nutricionais da suplementação com carboidratos altamente fermentáveis. Abstract in english Focal symmetrical encephalomalacia (FSE) is the most prominent lesion seen in the chronic form of enterotoxemia by Clostridium perfringens type D. This paper reports FSE in sheep in Brazil. Six deaths occurred within a seven days period in a flock of 70, four to 30-month-old Santa Inês sheep in the [...] state of Paraíba in the Brazilian semiarid. The flock was grazing a paddock of irrigated sprouting Cynodon dactylon (Tifton grass), and supplemented, ad libitum, with a concentrate of soybean, corn and wheat. Nervous signs included blindness and recumbence. A 19 month-old sheep was examined clinically and necropsied after a clinical course of three days. Gross lesions were herniation of the cerebellar vermis and multifocal, bilateral, symmetric brownish areas in the internal capsule, thalamus and cerebellar peduncles. Histologic lesions were multifocal, bilateral malacia with some neutrophils, swelling of blood vessels endothelium, perivascular edema, and hemorrhages. The flock was vaccinated, before the outbreak, with only one dose of Clostridium perfringens type D vaccine. Two factors are suggested to be important for the occurrence of the disease: insufficient immunity due to the incorrect vaccination; and high nutritional levels by the supplementation with highly fermentable carbohydrates.

Luciano A., Pimentel; Diego M., Oliveira; Glauco J.N., Galiza; Antônio F.M., Dantas; Francisco, Uzal; Franklin, Riet-Correa.

2010-05-01

194

Focal symmetrical encephalomalacia in sheep Encefalomalacia focal simétrica em ovino  

Directory of Open Access Journals (Sweden)

Full Text Available Focal symmetrical encephalomalacia (FSE is the most prominent lesion seen in the chronic form of enterotoxemia by Clostridium perfringens type D. This paper reports FSE in sheep in Brazil. Six deaths occurred within a seven days period in a flock of 70, four to 30-month-old Santa Inês sheep in the state of Paraíba in the Brazilian semiarid. The flock was grazing a paddock of irrigated sprouting Cynodon dactylon (Tifton grass, and supplemented, ad libitum, with a concentrate of soybean, corn and wheat. Nervous signs included blindness and recumbence. A 19 month-old sheep was examined clinically and necropsied after a clinical course of three days. Gross lesions were herniation of the cerebellar vermis and multifocal, bilateral, symmetric brownish areas in the internal capsule, thalamus and cerebellar peduncles. Histologic lesions were multifocal, bilateral malacia with some neutrophils, swelling of blood vessels endothelium, perivascular edema, and hemorrhages. The flock was vaccinated, before the outbreak, with only one dose of Clostridium perfringens type D vaccine. Two factors are suggested to be important for the occurrence of the disease: insufficient immunity due to the incorrect vaccination; and high nutritional levels by the supplementation with highly fermentable carbohydrates.Encefalomalacia focal simétrica (EFS é a lesão mais proeminente vista nas formas subaguda ou crônica da enterotoxemia por Clostridium perfringens tipo D. Este trabalho relata EFS em ovinos no semiárido do estado da Paraíba. Seis ovinos morreram, em um período de sete dias, dentro de um rebanho de 70 animais, da raça Santa Inês, entre 4-30 meses de idade, que pastavam em piquete de Cynodon dactylon (capim Tifton, que estava rebrotando. Os ovinos eram suplementados com um concentrado de soja, trigo e milho. Os sinais nervosos incluíam cegueira e decúbito lateral. Um ovino de 19 meses de idade foi examinado clinicamente e necropsiado, depois de um curso clínico de 3 dias. Macroscopicamente foram observadas herniação do cerebelo e áreas acastanhadas, multifocais, simétricas e bilaterais na cápsula interna, tálamo e pedúnculo cerebelar. Histologicamente observou-se malacia, bilateral e simétrica, com alguns neutrófilos, tumefação das células endoteliais dos vasos sanguíneos, edema perivascular e hemorragia. O rebanho foi vacinado, antes do surto, com umaúnica dose de vacina para Clostridium perfringens tipo D. Dois fatores são sugestivos quanto a importância da ocorrência da enfermidade: imunidade insuficiente devida à vacinação incorreta; e altos níveis nutricionais da suplementação com carboidratos altamente fermentáveis.

Luciano A. Pimentel

2010-05-01

195

Focal Segmental Glomerulosclerosis and Kidney Transplantation  

Directory of Open Access Journals (Sweden)

Full Text Available The recurrence rate of focal segmental glomerulosclerosis after kidney transplantation is ranging between 20% and 40%. Focal segmental glomerulosclerosis is associated with poor graft survival. In this review, the etiology, pathogenesis, clinicopathological features, risk factors of recurrence, and updated lines of management are discussed.

Osama Gheith

2013-07-01

196

Focal Segmental Glomerulosclerosis and Kidney Transplantation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The recurrence rate of focal segmental glomerulosclerosis after kidney transplantation is ranging between 20% and 40%. Focal segmental glomerulosclerosis is associated with poor graft survival. In this review, the etiology, pathogenesis, clinicopathological features, risk factors of recurrence, and updated lines of management are discussed.

Osama Gheith; Rashad Hassan

2013-01-01

197

Prenatal sonographic diagnosis of focal musculoskeletal anomalies  

Energy Technology Data Exchange (ETDEWEB)

Focal musculoskeletal anomalies are various and may be an isolated finding or may be found in conjunction with numerous associations, including genetic syndromes, Karyotype abnormals, central nervous system anomalies and other general musculoskeletal disorders. Early prenatal diagnosis of these focal musculoskeletal anomalies nor only affects prenatal care and postnatal outcome but also helps in approaching other numerous associated anomalies.

Ryu, Jung Kyu; Cho, Jeong Yeon; Lee, Young Ho; Kim, Ei Jeong; Chun, Yi Kyeong [Samsung Cheil Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2002-09-15

198

Epidemiology of extra-articular manifestations in rheumatoid arthritis.  

Science.gov (United States)

Extra-articular RA (ExRA) includes a wide variety of disease manifestations. Although rheumatologists in general are aware that such events are clinically important, the heterogeneity of available data, including discrepancies in case definitions, has complicated constructive discussions on this aspect of the RA disease phenotype. In recent years, there has been a growing recognition of the importance of co-morbidity in patients with RA. ExRA manifestations are not uncommon, explain excess mortality in RA and are predicted by smoking and autoantibodies. Further studies of the mechanisms underlying these associations are likely to be important in improving our understanding of the systemic nature of RA. This article discusses the methodological issues involved in the study of ExRA manifestations, presents suggested criteria that have been used in clinical studies, and reviews important surveys of the epidemiology of extra-articular RA. PMID:15163106

Turesson, C; Jacobsson, L T H

2004-01-01

199

Intra-articular lipoma arborescens of the knee joint  

Directory of Open Access Journals (Sweden)

Full Text Available Intra-articular lipoma arborescens (LA is a rare entity that can present with monoarticular or polyarticular involvement of joints such as knees, ankles, hips, shoulders, and elbows. We describe a case in a 26-year-old man who presented with intermittent pain and swelling of the left knee joint for the previous 2 years. Physical examination showed only tenderness over the medial line of the left knee joint. MRI found only joint effusion; therefore, the patient was referred to the orthopedic clinic where he underwent arthroscopy, which revealed a diffuse yellow soft tissue synovial papillary growth involving both medial and lateral gutters of the suprapatellar pouch. A biopsy reported intra-articular LA. This is the first case of LA reported in Saudi Arabia. LA should be included in the clinical and radiologic differential diagnosis of cases with persistent knee joint effusion.

Al-Shraim Mubarak

2011-01-01

200

Tribological evaluation of hydrogels for artificial articular cartilage  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Bacterial cellulose (BC) is a natural and biocompatible gel with unique properties, such as high water holding capacity, ultra-fine fibre network and high strength that make it an interesting material for biotribological purposes. In this work, unmodified BC pellicles were grown from Gluconacetobacter xylinus in order to be used as tribological samples against bovine articular cartilage (BAC) in the presence of phosphate buffered saline (PBS). The tribological assessment was accomplished usin...

Lopes, J. L.; Machado, J. M.; Castanheira, L.; Granja, P. L.; Gama, F. M.; Dourado, Fernando; Gomes, J. R.

2012-01-01

 
 
 
 
201

Phenotypic modulation of human articular chondrocytes by bistratene A  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Chondrocytes undergo phenotypic alterations following extended periods in monolayer culture, i.e., they become bipolar and flattened, proliferate, and synthesise type I as opposed to type II collagen. This process has been termed chondrocyte dedifferentiation. Bistratene A is a macrolide polyether that specifically activates the delta isoform of protein kinase C (PKCdelta) in some cell types. Here, we show that dedifferentiated human articular chondrocytes became rounded and underwent cell gr...

Gargiulo B. J.; Cragg P.

2002-01-01

202

A vision on the future of articular cartilage repair  

Digital Repository Infrastructure Vision for European Research (DRIVER)

An AO Foundation (Davos, Switzerland) sponsored workshop "Cell Therapy in Cartilage Repair" from the Symposium "Where Science meets Clinics" (September 5-7, 2013, Davos) gathered leaders from medicine, science, industry, and regulatory organisations to debate the vision of cell therapy in articular cartilage repair and the measures that could be taken to narrow the gap between vision and current practice. Cell-based therapy is already in clinical use to enhance the repair of cartilage lesions...

Cucchiarini, M.; Madry, H.; Guilak, F.; Db, Saris; Mj, Stoddart; Koon Wong, M.; Roughley, P.

2014-01-01

203

Rapid effects of hypoxia on H+ homeostasis in articular chondrocytes.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Articular chondrocytes experience low oxygen (O(2)) levels compared with many other tissues, and values fall further in disease states. Chondrocyte intracellular pH (pH(i)) is a powerful modulator of matrix synthesis and is principally regulated by Na(+)-H(+) exchange (NHE). In equine chondrocytes, NHE is inhibited when cells are incubated for 3 h at low O(2), leading to intracellular acidosis. O(2)-dependent changes in reactive oxygen species (ROS) levels appear to underlie this effect. The ...

Gibson, Js; Mccartney, D.; Sumpter, J.; Fairfax, Tp; Milner, Pi; Edwards, Hl; Wilkins, Rj

2009-01-01

204

Pannocytes: distinctive cells found in rheumatoid arthritis articular cartilage erosions.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A distinctive cell was identified from sites of rheumatoid arthritis cartilage injury. Similar cells are not found in lesions of osteoarthritis cartilage. We have designated them as pannocytes (PCs). Their rhomboid morphology differs from the bipolar shape of fibroblast-like synoviocytes or the spherical configuration of primary human articular chondrocytes. Chondrocytes are short-lived, whereas the original PC line grew for 25 passages before becoming senescent. Features in common with cultu...

Zvaifler, N. J.; Tsai, V.; Alsalameh, S.; Von Kempis, J.; Firestein, G. S.; Lotz, M.

1997-01-01

205

Quantitative magnetic resonance imaging of articular cartilage in osteoarthritis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Magnetic resonance imaging of articular cartilage has recently been recognized as a tool for the characterization of cartilage morphology, biochemistry and function. In this paper advancements in cartilage imaging, computation of cartilage volume and thickness, and measurement of relaxation times (T2 and T1?) are presented. In addition, the delayed uptake of Gadolinium DTPA as a marker of proteoglycan depletion is also reviewed. The cross-sectional and longitudinal studies using these imagin...

Blumenkrantz, G.; Majumdar, S.

2007-01-01

206

Articular facets syndrome: diagnostic grading and treatment options  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Approximately 80% of the adult population suffers from chronic lumbar pain with episodes of acute back pain. The aetiology of this disorder can be very extensive: degenerative scoliosis, spondiloarthritis, disc hernia, spondylolysis, spondylolisthesis and, in the most serious cases, neoplastic or infectious diseases. For several years, the attention of surgeons was focused on the articular facets syndrome (Lilius et al. in J Bone Joint Surg (Br) 71-B:681–684, 1998), characterised clinically...

Misaggi, B.; Gallazzi, M.; Colombo, M.; Ferraro, M.

2009-01-01

207

A vision on the future of articular cartilage repair  

Directory of Open Access Journals (Sweden)

Full Text Available An AO Foundation (Davos, Switzerland sponsored workshop "Cell Therapy in Cartilage Repair" from the Symposium "Where Science meets Clinics" (September 5-7, 2013, Davos gathered leaders from medicine, science, industry, and regulatory organisations to debate the vision of cell therapy in articular cartilage repair and the measures that could be taken to narrow the gap between vision and current practice. Cell-based therapy is already in clinical use to enhance the repair of cartilage lesions, with procedures such as microfracture and articular chondrocyte implantation. However, even though long term follow up is good from a clinical perspective and some of the most rigorous randomised controlled trials in the regenerative medicine/orthopaedics field show beneficial effect, none of these options have proved successful in restoring the original articular cartilage structure and functionality in patients so far. With the remarkable recent advances in experimental research in cell biology (new sources for chondrocytes, stem cells, molecular biology (growth factors, genes, biomaterials, biomechanics, and translational science, a combined effort between scientists and clinicians with broad expertise may allow development of an improved cell therapy for cartilage repair. This position paper describes the current state of the art in the field to help define a procedure adapted to the clinical situation for upcoming translation in the patient.

M Cucchiarini

2014-05-01

208

A vision on the future of articular cartilage repair.  

Science.gov (United States)

An AO Foundation (Davos, Switzerland) sponsored workshop "Cell Therapy in Cartilage Repair" from the Symposium "Where Science meets Clinics" (September 5-7, 2013, Davos) gathered leaders from medicine, science, industry, and regulatory organisations to debate the vision of cell therapy in articular cartilage repair and the measures that could be taken to narrow the gap between vision and current practice. Cell-based therapy is already in clinical use to enhance the repair of cartilage lesions, with procedures such as microfracture and articular chondrocyte implantation. However, even though long term follow up is good from a clinical perspective and some of the most rigorous randomised controlled trials in the regenerative medicine/orthopaedics field show beneficial effect, none of these options have proved successful in restoring the original articular cartilage structure and functionality in patients so far. With the remarkable recent advances in experimental research in cell biology (new sources for chondrocytes, stem cells), molecular biology (growth factors, genes), biomaterials, biomechanics, and translational science, a combined effort between scientists and clinicians with broad expertise may allow development of an improved cell therapy for cartilage repair. This position paper describes the current state of the art in the field to help define a procedure adapted to the clinical situation for upcoming translation in the patient. PMID:24802612

Cucchiarini, M; Madry, H; Guilak, F; Saris, D B; Stoddart, M J; Koon Wong, M; Roughley, P

2014-01-01

209

Effect of donor age on DNA repair by articular chondrocytes  

International Nuclear Information System (INIS)

The hypothesis that aging of articular chondrocytes at a cellular level results from loss of DNA repair capability was studied by two different measures: unscheduled DNA synthesis (UDS) and O6-methylguanine acceptor protein (MGAP) activity. UDS following damage by 254 nm ultraviolet irradiation (20J/m2) was examined in intact articular cartilage from rabbits of different ages. Semiconservative DNA synthesis was suppressed with hydroxurea and repair followed by the incorporation of [3H]-thymidine ([3H]-dThd). After repair the cartilage was digested in proteinase K (0.5mg/ml) with dodecyl sodium sulfate (0.2%) and DNA determined with Hoechst 33258 dye. UDS (dpm [3H]-dThd/?g DNA) was greater in articular cartilage from 3- than 39-month-old rabbits. MGAP was studied in cell extracts of cultured human and rabbit chondrocytes by transfer of [3H] O6-methyl groups from exogenous DNA to protein. It was significantly less in rabbit than in human cells on a per protein or DNA basis. There was no decline in this activity in human chondrocytes from newborn to 60 years of age; and rabbits from 3- to 36-months-old. The data indicate that in the two different repair mechanisms, age differences are found with resting but not dividing chondrocytes

210

Effect of donor age on DNA repair by articular chondrocytes  

Energy Technology Data Exchange (ETDEWEB)

The hypothesis that aging of articular chondrocytes at a cellular level results from loss of DNA repair capability was studied by two different measures: unscheduled DNA synthesis (UDS) and O/sup 6/-methylguanine acceptor protein (MGAP) activity. UDS following damage by 254 nm ultraviolet irradiation (20J/m/sup 2/) was examined in intact articular cartilage from rabbits of different ages. Semiconservative DNA synthesis was suppressed with hydroxurea and repair followed by the incorporation of (/sup 3/H)-thymidine ((/sup 3/H)-dThd). After repair the cartilage was digested in proteinase K (0.5mg/ml) with dodecyl sodium sulfate (0.2%) and DNA determined with Hoechst 33258 dye. UDS (dpm (/sup 3/H)-dThd/..mu..g DNA) was greater in articular cartilage from 3- than 39-month-old rabbits. MGAP was studied in cell extracts of cultured human and rabbit chondrocytes by transfer of (/sup 3/H) O/sup 6/-methyl groups from exogenous DNA to protein. It was significantly less in rabbit than in human cells on a per protein or DNA basis. There was no decline in this activity in human chondrocytes from newborn to 60 years of age; and rabbits from 3- to 36-months-old. The data indicate that in the two different repair mechanisms, age differences are found with resting but not dividing chondrocytes.

Lipman, J.M.

1986-05-01

211

Polyethylene contact stresses, articular congruity, and knee alignment.  

Science.gov (United States)

Increased conformity at the tibiofemoral articulation increases contact area and reduces contact stresses in total knee arthroplasty. Malalignment, however, can increase polyethylene contact stresses. The effect of knee alignment and articular conformity on contact stresses was evaluated in a finite element model. The polyethylene insert and femoral component were modeled in high- and low-conformity conditions. An axial tibial load of 3000 N was applied across the tibiofemoral articulation at different knee positions ranging from 0 degrees, to 90 degrees, flexion, 0 to 10 mm anteroposterior translation, 0 degrees to 10 degrees axial rotation, and coronal plane angulation (liftoff). Increased conformity significantly reduced contact stresses in neutral alignment (by 44% at 0 degrees flexion and 36% at 60 degrees and 90 degrees flexion). Liftoff significantly increased contact stresses in low- and high-conformity conditions, but to a lesser degree in the high-conformity condition. Malalignment in rotation was most detrimental especially with the high-conformity insert design. Overall, increasing articular conformity reduced stresses when the knee was well-aligned. However, malalignment in axial rotation was detrimental. Mobile-bearing knee designs with increased articular congruity may result in lower contact stresses, especially the rotating-bearing designs that theoretically minimize rotational malalignment. PMID:11716388

D'Lima, D D; Chen, P C; Colwell, C W

2001-11-01

212

Colonies in engineered articular cartilage express superior differentiation.  

Science.gov (United States)

In view of poor regeneration potential of the articular cartilage, in-vitro engineering of cartilage tissue offers a promising option for progressive joint disease. This study aims to develop a biologically engineered articular cartilage for autologous transplantation. The initial work involved determination of chondrocyte yield and viability, and morphological analysis. Cartilage was harvested from the knee, hip and shoulder joints of adult New Zealand white rabbits and chondrocytes were isolated by enzymatic digestion of the extra-cellular matrix before serial cultivation in DMEM/Ham's F12 media as monolayer cultures. No differences were noted in cell yield. Although chondrocytes viability was optimal (>93%) following harvest from native cartilage, their viability tended to be lowered on passaging. Chondrocytes aggregated in isogenous colonies comprising ovoid cells with intimate intracellular contacts and readily exhibited Safranin-O positive matrix; features typically associated with articular cartilage in-vivo. However, chondrocytes also existed concurrently in scattered bipolar/multipolar forms lacking Safranin-O expression. Therefore, early data demonstrated successful serial culture of adult chondrocytes with differentiated morphology seen in established chondrocyte colonies synthesizing matrix proteoglycans. PMID:16381284

Selvaratnam, L; Abd Rahim, S; Kamarul, T; Chan, K Y; Sureshan, S; Penafort, R; Ng, C L L

2005-07-01

213

Focal brain inflammation and autism.  

Science.gov (United States)

Increasing evidence indicates that brain inflammation is involved in the pathogenesis of neuropsychiatric diseases. Autism spectrum disorders (ASD) are characterized by social and learning disabilities that affect as many as 1/80 children in the USA. There is still no definitive pathogenesis or reliable biomarkers for ASD, thus significantly curtailing the development of effective therapies. Many children with ASD regress at about age 3 years, often after a specific event such as reaction to vaccination, infection, stress or trauma implying some epigenetic triggers, and may constitute a distinct phenotype. ASD children respond disproportionally to stress and are also affected by food and skin allergies. Corticotropin-releasing hormone (CRH) is secreted under stress and together with neurotensin (NT) stimulates mast cells and microglia resulting in focal brain inflammation and neurotoxicity. NT is significantly increased in serum of ASD children along with mitochondrial DNA (mtDNA). NT stimulates mast cell secretion of mtDNA that is misconstrued as an innate pathogen triggering an auto-inflammatory response. The phosphatase and tensin homolog (PTEN) gene mutation, associated with the higher risk of ASD, which leads to hyper-active mammalian target of rapamycin (mTOR) signalling that is crucial for cellular homeostasis. CRH, NT and environmental triggers could hyperstimulate the already activated mTOR, as well as stimulate mast cell and microglia activation and proliferation. The natural flavonoid luteolin inhibits mTOR, mast cells and microglia and could have a significant benefit in ASD. PMID:23570274

Theoharides, Theoharis C; Asadi, Shahrzad; Patel, Arti B

2013-01-01

214

Idiopathic generalized epilepsies imitating focal epilepsies.  

Science.gov (United States)

Classification of epileptic seizures and epilepsy syndromes as either focal or generalized is a fundamental and early part in the diagnostic process and is generally fairly easily accomplished. However, in patients with idiopathic generalized epilepsies, seizure and EEG features may suggest, particularly to the unwary, the occurrence of focal rather than generalized seizures. Misinterpretation of typical absence seizures as focal seizures, especially as temporal lobe seizures and of myoclonic seizures as focal clonic seizures, is a relatively common error and focal features during generalized tonic-clonic seizures may also be quite common. Sequences of seizures in idiopathic generalized epilepsies (such as absences or jerks followed by generalized tonic-clonic seizures) may also cause confusion. Versive and circling seizures are seizure types whose ictal semiology is clearly focal; nevertheless such seizures are described in idiopathic generalized epilepsies accompanied by generalized EEG discharges. The occurrence of focal EEG abnormalities in certain idiopathic generalized epilepsy syndromes is common. This is best known in juvenile myoclonic epilepsy. PMID:16302881

Ferrie, Colin D

2005-01-01

215

Dynamic mechanisms of neocortical focal seizure onset.  

Science.gov (United States)

Recent experimental and clinical studies have provided diverse insight into the mechanisms of human focal seizure initiation and propagation. Often these findings exist at different scales of observation, and are not reconciled into a common understanding. Here we develop a new, multiscale mathematical model of cortical electric activity with realistic mesoscopic connectivity. Relating the model dynamics to experimental and clinical findings leads us to propose three classes of dynamical mechanisms for the onset of focal seizures in a unified framework. These three classes are: (i) globally induced focal seizures; (ii) globally supported focal seizures; (iii) locally induced focal seizures. Using model simulations we illustrate these onset mechanisms and show how the three classes can be distinguished. Specifically, we find that although all focal seizures typically appear to arise from localised tissue, the mechanisms of onset could be due to either localised processes or processes on a larger spatial scale. We conclude that although focal seizures might have different patient-specific aetiologies and electrographic signatures, our model suggests that dynamically they can still be classified in a clinically useful way. Additionally, this novel classification according to the dynamical mechanisms is able to resolve some of the previously conflicting experimental and clinical findings. PMID:25122455

Wang, Yujiang; Goodfellow, Marc; Taylor, Peter Neal; Baier, Gerold

2014-08-01

216

Development and investigation of an absorbable scaffold for the treatment of articular cartilage defects  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Aufgrund der unzureichenden regenerativen Fähigkeiten des Gelenkknorpels führen bereits kleine Läsionen zu progressiven Gelenkbeschwerden, die in einer Arthrose und nachfolgender Invalidität enden können. Bedingt ist diese Problematik durch die spezielle Anatomie des Knorpelgewebes, insbesondere durch seine Avaskularität. Da die bisher eingesetzten konventionellen Behandlungsmethoden bei der Regeneration von zonal aufgebautem, hyalinem Knorpel scheitern, werden seit etwa 20 Jahren neue,...

Thiem, Annette

2011-01-01

217

A hydrophobically-modified alginate gel system: utility in the repair of articular cartilage defects.  

Science.gov (United States)

Alginate is a family of natural polysaccharides, widely used in industry and medicine for many applications, with its non toxic nature, gentle sol/gel transition procedure and low cost, alginate inferior biomechanical properties have limited its utility especially in tissue engineering. Additionally, ionically cross-linked alginate hydrogels generally lose most of their initial mechanical and swelling properties within a few hours in physiological solution. In order to overcome these limitations, the referenced alginate was treated by covalent fixation of octadecyl chains onto the polysaccharide backbone by esterification. In semi dilute solution, intermolecular hydrophobic interactions of long alkyl chains result in the formation of physical hydrogels, which can then be reinforced by the addition of calcium chloride. FTIR studies clearly showed the presence of ester bonds at 1612 and 1730 cm(-1) indicating that the alkyl groups are incorporated in the backbone of resulting polymer. The endothermic peak and exothermic peak present in the DSC thermogram of Alg-C18 had shifted to lower temperatures comparing to native alginate (from 106 to 83°C and from 250 to 245°C, respectively) due to the esterification reaction that leads to high hydrophobic nature of the modified sample. From rheological experiments, it can be inferred that the combination of both calcium bridges and intermolecular hydrophobic interaction in the treated alginate leads to enhanced gel strength accompanied by more stable structure in physiological solution comparing to native sodium alginate hydrogel. Finally, the modified alginate tended to have no toxic effects on mesenchymal stem cell culture, rather it supported MSC chondrogenic differentiation. PMID:21833609

Ghahramanpoor, Mohammad Kazem; Hassani Najafabadi, Sayed Alireza; Abdouss, Majid; Bagheri, Fatemeh; Baghaban Eslaminejad, Mohamadreza

2011-10-01

218

Extra-articular manifestations are uncommon in southern Chinese with rheumatoid arthritis.  

Science.gov (United States)

Rheumatoid arthritis is characterized by both articular and extra-articular manifestations. Few studies have addressed the prevalence of extra-articular manifestations in non-Caucasoid races. We have studied 153 Southern Chinese patients with RA and found that such features are uncommon when compared with previous reports in Caucasoids. The only extra-articular manifestations were rheumatoid nodules which were present in 4.6%, and episcleritis and cutaneous vasculitis in 0.7% each. A further 12.4% had mild sicca symptoms. These findings were in direct contrast with the severity of articular disease as 73% of patients had erosive disease which was graded as severe in 37%. The reason for the low prevalence of extra-articular manifestations is not known but may be due, in part, to the rarity of the HLA-DR4 subtype, HLA-Dw4 in the Southern Chinese population. PMID:8448610

Cohen, M G; Li, E K; Ng, P Y; Chan, K L

1993-03-01

219

Spina bifida and unilateral focal destruction of the distal femoral epiphysis  

Energy Technology Data Exchange (ETDEWEB)

Focal destruction of the postero-lateral distal femoral epiphysis was present on radiographs in two children with spina bifida and objective lower limb sensory loss. Each patient presented with painless swelling of the knee. In one patient the epiphysis showed sclerosis and fragmentation associated with a defect. In the second patient the destructive change was the dominant radiographic abnormality and simulated bone tumor. Computed tomography in this patient showed a bone fragment occupying the defect suggesting epiphyseal fracture. The lesions in each patient were believed to be traumatic in origin and to represent a stage in the development toward neuropathic arthropathy.

Wolverson, M.K.; Sundaram, M.; Graviss, E.R.

1981-03-01

220

Spina bifida and unilateral focal destruction of the distal femoral epiphysis  

International Nuclear Information System (INIS)

Focal destruction of the postero-lateral distal femoral epiphysis was present on radiographs in two children with spina bifida and objective lower limb sensory loss. Each patient presented with painless swelling of the knee. In one patient the epiphysis showed sclerosis and fragmentation associated with a defect. In the second patient the destructive change was the dominant radiographic abnormality and simulated bone tumor. Computed tomography in this patient showed a bone fragment occupying the defect suggesting epiphyseal fracture. The lesions in each patient was believed to be traumatic in origin and to represent a stage in the development toward neuropathic arthropathy. (orig.)

 
 
 
 
221

MODELADO MATEMÁTICO DEL COMPORTAMIENTO MECÁNICO DE UN FRAGMENTO DE CARTÍLAGO ARTICULAR / MATHEMATICAL MODELING OF THE MECHANICAL BEHAVIOR OF AN ARTICULAR CARTILAGE PIECE  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish El cartílago articular es un material biológico poroelástico que permite la distribución de las cargas mecánicas y el movimiento de las articulaciones. Como material bifásico, en presencia de carga, el cartílago articular deforma su matriz sólida y modifica la presión hidrostática del fluido en su i [...] nterior. El objetivo del presente trabajo es implementar numéricamente un modelo matemático que predice el comportamiento mecánico del cartílago articular teniendo en cuenta la dualidad entre la matriz sólida y el líquido articular, y la característica de poroelasticidad. Utilizando una metodología basada en el método de los elementos finitos, se simuló el comportamiento de un fragmento de cartílago articular en una y dos dimensiones, ante cargas mecánicas de tensión, compresión y oscilación. El análisis de los resultados permite validar cualitativamente el comportamiento poroelástico del modelo debido a la deformación de la matriz sólida y a la salida de fluido que modifica la presión del mismo de manera similar a lo reportado en trabajos experimentales. Se concluye que el modelo matemático permite realizar predicciones sobre el comportamiento biomecánico del cartílago articular, contribuyendo al proceso investigativo en áreas como la biomecánica y la ingeniería de tejidos. Abstract in english The articular cartilage is a poroelastic biological material that allows the distribution of mechanical loads and the joint movements. As a biphasic material, in presence of load, the articular cartilage deforms its solid matrix and modifies the fluid hydrostatic pressure inside. The aim of this wor [...] k is to implement numerically a mathematical model that predicts the mechanical behaviour of articular cartilage taking into account the duality between the solid matrix and articular liquid, and its poroelastic feature. Using a finite element method approach , the response of a piece of articular cartilage in one and two dimensions has been simulated, with tensile, compresive and oscillative mechanical loads. The analysis of results allows a qualitatively validation of the poroelastic behavior of the model due to the solid matrix deformation and the fluid outflow that causes variations of pressures inside the articular cartilage according with reported trials. We conclude that the mathematical model allows the prediction of the articular cartilage biomechanical behaviour. Our results contribute to the investigative processes in fields of study like biomechanics and tissue engineering

NANCY STELLA, LANDÍNEZ; JUAN CARLOS, VANEGAS; DIEGO ALEXANDER, GARZÓN.

2009-06-01

222

Cryoscanning electron microscopy of loaded articular cartilage with special reference to the surface amorphous layer.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The surface layer (i.e. the surface lamina) of articular cartilage, which is devoid of a collagen fibril network or cells, was investigated in the pig and human. It overlies the collagenous main part of the articular cartilage which contains chondrocytes and is thought to be important biomechanically. In order to examine morphological changes in this layer when under load, knee articular cartilage of the pig, along with the underlying subchondral bone, was compressed with a cylindrical indent...

Kobayashi, S.; Yonekubo, S.; Kurogouchi, Y.

1996-01-01

223

Cellular origin of neocartilage formed at wound edges of articular cartilage in a tissue culture experiment  

Digital Repository Infrastructure Vision for European Research (DRIVER)

OBJECTIVE: The regeneration capacity of cartilage in general is limited. Complete repair of partial thickness articular cartilage has only been reported in a fetal sheep model. However, in long-term culture studies of articular cartilage explants we have observed outgrowth of chondrocytes and neocartilage formation at wound edges. This illustrates that under optimal circumstances articular cartilage is capable to regenerate hyaline cartilage. Recent studies suggest the presence of mesenchymal...

Bos, P. K.; Kops, N.; Verhaar, J. A. N.; Osch, G. J. V. M.

2008-01-01

224

Mineralization of Articular Cartilage in the Sprague-Dawley Rat: Characterization and Mechanical Analysis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The formation of mineralized deposits in human articular cartilage is a common occurrence [1–4]; however, the relationship between mineral deposition and material properties of the articular cartilage is not well understood nor the relationship between mineral deposition and the development of degenerative joint disease. Several different crystalline structures have been identified in articular cartilage and synovial fluid including monosodium urate, calcium pyrophosphate dihydrate (CPPD), ...

Roemhildt, M. L.; Beynnon, B. D.; Gardner-morse, M.

2012-01-01

225

Blood supply of the articular disc of the antebrachiocarpal joint in dogs.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The normal vascular anatomy of the articular disc of 48 antebrachiocarpal joints was studied in 24 dogs (12 puppies and 12 adult animals) using an India ink vascular injection technique. It was found that the articular disc receives its blood supply mainly from the palmar and dorsal branches of the palmar interosseous artery. Branches of these 2 arteries arborise and give direct peridiscal vessels to the dorsal, proximal and palmar sides of the articular disc. The peridiscal vessels ramify an...

Mikic?, Z. D.

1992-01-01

226

Focal pancreatic enlargement: differentiation between pancreatic adenocarcinoma and focal pancreatitis on CT and ERCP  

International Nuclear Information System (INIS)

To differentiate the pancreatic adenocarcinoma from focal pancreatitis on CT and ERCP in cases of focal pancreatic enlargement. We analysed CT findings of 66 patients of pancreatic adenocarcinoma (n = 45) or focal pancreatitis (n = 21) with respect to size, density, calcification, pancreatic or biliary duct dilatation, fat plane obliteration around the vessels, direction of retroperitoneal extension, lymphadenopathy, pseudocyst formation and atrophy of pancreas. ERCP available in 48 patients were analysed in respect to morphologic appearance of CBD and pancreatic duct, and distance between the two ducts. The patients in focal pancreatitis were younger with more common history of alcohol drinking. There was no statistical difference in calcifications of the mass (18% in the adenocarcinoma, 33% in the focal pancreatitis), but a tendency of denser, larger number of calcifications was noted in focal pancreatitis. The finding of fat plane obliteration around the vessels were more common in pancreatic adenocarcinoma, and fascial thickenings were more prominent in focal pancreatitis, although not statistically significant. On ERCP, there were no differential points of CBD, pancreatic duct morphology, but distance between the two ducts at the lesion center was more wider in focal pancreatitis. Differentiating focal pancreatitis from pancreatic adenocarcinoma is difficult. However, we should consider the possibility of focal pancreatitis in cases of patients with young age, hais in cases of patients with young age, having alcoholic history in association with CT findings of large numbers of and dense calcifications, and ERCP findings of prominent separation of two duct at the lesion center

227

Extra-articular manifestations of seronegative and seropositive rheumatoid arthritis.  

Science.gov (United States)

Although considered a "joint disease," rheumatoid arthritis is associated with the involvement of extra-articular manifestations. The aim of the study is the investigation and comparison of frequency and type of extra-articular manifestations in a well defined community based cohort of patients with seropositive and seronegative rheumatoid arthritis. Using the ACR (1987) criteria for rheumatoid arthritis, patients have been classified into the 2nd and 3rd functional class (ARA). The studied group consisted of 125 seronegative patients with titters lower than 1:64 as defined by Rose-Waaler test, whereas the control group consisted of 125 seropositive patients with titters of 1:64 or higher. All patients were between 25-60 years of age (Xb=49,96), with disease duration between 1-27 years (Xb=6,41). In order to present the findings of the study, the structure, prevalence, arithmetic mean (Xb), standard deviation (SB), variation quotient (QV%) and variation interval (Rmax-Rmin) have been used. Probability level has been expressed by prheumatoid core" in the seropositive subset (chi2=4,80, pRheumatoid nodules were more frequent in seropositive subset (12%:16%), in both sexes; however, they were not of significant statistical difference. Neuropathy and lung diseases were also frequently present in seropositive group, but no statistical difference has been found regarding the statistical difference. Longer duration of the disease resulted in an increase of the number of extra-articular manifestations. Calculated linear correlation by Pearson, resulted as positive and high correlation in total (r=0,36, p<0,01), and for groups [(r=0,52, p<0,01) seronegative, (r=0,25, p<0,01) seropositive], nevertheless no significant statistical difference was found regarding the sero-status. In conclusion, extra-articular manifestations are more frequent in the seropositive patients. The longer the duration of the disease the larger the number of extra-articular manifestations. Differences with regard to sero-status and sex, with some exceptions, are not observed. PMID:20192927

Sahatciu-Meka, Vjollca; Rexhepi, Sylejman; Manxhuka-Kerliu, Suzana; Rexhepi, Mjellma

2010-02-01

228

Degenerative joint disease in cattle and buffaloes in the Amazon region: a retrospective study / Doença articular degenerativa em bovinos e búfalos na Amazônia: estudo retrospectivo  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Foi realizado um estudo retrospectivo sobre os aspectos epidemiológicos e clínico-patológicos em bovinos e búfalos com doença articular degenerativa (DAD) no estado do Pará, Brasil. Durante os anos de 1999 a 2014 foram avaliados 11 bovinos e 24 bubalinos. Todos os animais atendidos com suspeita clín [...] ica de DAD foram submetidos a exame clínico do sistema locomotor. Foram necropsiados sete bovinos e oito bubalinos com sinais clínicos da enfermidade. Os sinais clínicos comuns observados em ambas as espécies foram claudicação crônica, andar rígido, alterações posturais, crepitações audíveis no membro acometido, decúbito prolongado, dificuldade para levantar, e emagrecimento progressivo. As lesões articulares evidenciadas na necropsia consistiram em irregularidade da superfície articular, presença de erosão na cartilagem articular e no tecido ósseo subjacente, proliferação de tecido ósseo periarticular com formação de osteófitos. Tanto nos bovinos como nos bubalinos as articulações mais acometidas foram as dos membros posteriores. Nos bubalinos, possivelmente o principal fator predisponente ao surgimento de DAD foi à deficiência de fósforo, ao contrário dos bovinos, nos quais os defeitos de conformação anatômica dos membros posteriores, traumas crônicos em virtude da atividade exercida, como a coleta de sêmen e a idade avançada, foram o que, possivelmente, contribuíram para surgimento da enfermidade. Abstract in english A retrospective study of the epidemiological and clinic-pathological aspects of cattle and buffaloes with degenerative joint disease (DJD) was conducted in the state of Pará, Brazil. From 1999 to 2014, eleven cattle and 24 buffaloes were evaluated. All the treated animals with suspected DJD underwen [...] t a clinical examination of the musculoskeletal system. In seven cattle and eight buffaloes with clinical signs of the disease postmortem examination was performed. The common clinical signs observed in both species were chronic lameness, stiff gait, postural changes, audible crackles in the affected limb, prolonged recumbency, difficulty in getting up and progressive weight loss. The lesions observed at necropsy were: irregular articular surfaces, erosion of the articular cartilage and the underlying bone tissue, and proliferation of the periarticular bone tissue with formation of osteophytes. The most affected joints in cattle and buffaloes wereof the hind limb. In buffaloes, the main predisposing factor to the onset of DJD was phosphorus deficiency. In cattle, defects of the anatomical conformation of the hind limbs, chronic trauma due to the activities performed, such as semen collection, and advanced age possibly contributed to the emergence of the disease.

José Diomedes, Barbosa; Danillo Henrique S., Lima; Alessandra S., Belo-Reis; Cleyton P., Pinheiro; Melina G.S., Sousa; Jenevaldo B., Silva; Felipe M., Salvarani; Carlos Magno C., Oliveira.

2014-09-01

229

Dynamic bone scans in osteo-articular pathology  

Energy Technology Data Exchange (ETDEWEB)

Three-phase radionuclide bone scanning was performed in patients with algodystrophy or osteonecrosis. This method is used to improve the specificity of ordinary bone scan. It explores vascularization and blood pool, then bone uptake in two symmetrical articulations. Non-focal hyperaemia and late diffuse uptake are in favour of algodystrophy, whereas a distinct focal hypervascularization and late uptake predominant in the femoral condyle area seem to be in favour of pre-radiological osteonecrosis.

Laurin, J.; Acquaviva, P.; Kaphan, G.

1986-06-21

230

Dynamic bone scans in osteo-articular pathology  

International Nuclear Information System (INIS)

Three-phase radionuclide bone scanning was performed in patients with algodystrophy or osteonecrosis. This method is used to improve the specificity of ordinary bone scan. It explores vascularization and blood pool, then bone uptake in two symmetrical articulations. Non-focal hyperaemia and late diffuse uptake are in favour of algodystrophy, whereas a distinct focal hypervascularization and late uptake predominant in the femoral condyle area seem to be in favour of pre-radiological osteonecrosis

231

Analgesic effect of intra-articular ketorolac in knee arthroscopy: comparison of morphine and bupivacaine.  

Science.gov (United States)

This prospective study assessed the postoperative analgesic effect of intra-articular ketorolac, morphine, and bupivacaine during arthroscopic outpatient partial meniscectomy. Group 1 patients (n=20) received postoperative injection of 60 mg intra-articular ketorolac, group 2 patients (n=20) 10 cc intra-articular bupivacaine 0.25%, group 3 patients (n=20) 1 mg intra-articular morphine diluted in 10 cc saline, and group 4 patients (n=20, controls) only 10 cc saline. We evaluated the postoperative analgesic effect (period measured from the end of the surgery until further analgesia was demanded), the level of postoperative pain (by visual analog scale 1, 2, 3, 12, and 24 h after surgery), and the need for additional pain medication (during the first 24 h after surgery). The best analgesic effect was in patients treated with intra-articular ketorolac, and this was statistically significant in: postoperative analgesic effect and the need for additional pain medication immediately after surgery, and after 24 h. No complications were found related to the intra-articular treatment. We conclude that 60 mg intra-articular ketorolac provides better analgesic effect than 10 cc intra-articular bupivacaine 0.25% or 1 mg intra-articular morphine. PMID:15197428

Calmet, J; Esteve, C; Boada, S; Giné, J

2004-11-01

232

[Mammary focal scleroelastotic lesion (author's transl)].  

Science.gov (United States)

Mammary focal scleroelastotic lesions are a newly recognized entity, with mammographic and macroscopic features simulating an infiltrating carcinoma but with benign microscopic features. The authors report two cases of this mammary lesion. PMID:554196

Grosso, F; De Florio, L; Albisinni, U; Ghigi, G; Turci, G A

1979-11-01

233

Focal renal masses: magnetic resonance imaging  

Energy Technology Data Exchange (ETDEWEB)

Thirty patients with focal renal masses were evaluated on a .12-Tesla resistive magnetic resonance unit using partial saturation and spin echo pulse sequence. Fifteen patients had cystic lesions, nine patients had renal cell carcinoma, two had metastatic lesions, one had an angiomyolipoma, and three had focal bacterial infection. Renal cell carcinomas demonstrated areas of increased signal using a partial saturation sequence. Magnetic resonance imaging accurately detected perinephric extension and vascular invasion in all patients. Metastatic disease to the kidney was uniformly low in signal, in contrast to primary renal cell carcinoma; an angiomyolipoma demonstrated very high signal intensity. Two masses resulting from acute focal bacterial nephritis were uniformly low in signal. Magnetic resonance imaging appears to be an accurate way of detecting, identifying, and staging focal renal masses.

Choyke, P.L.; Kressel, H.Y.; Pollack, H.M.; Arger, P.M.; Axel, L.; Mamourian, A.C.

1984-08-01

234

A Flat Focal Plane for LSST  

Science.gov (United States)

LSST is a wide field (10 sq. deg) survey instrument with active optics control and will provide better than 0.2 arcsecond instrumental contribution to imaging across the field. A principle requirement for achieving this is a very flat focal plane ( 10 microns PV) comprised of nearly 200 individual sensors, together with active feedback derived from 4 curvature wavefront sensors at the corners of the focal plane. We present our plans for building up a modular, flat focal plane for LSST and how flatness under operational conditions will be assured. The importance for delivering a flat focal plane will be underscored by discussing the specific structure of the LSST beam in the presence of residual wavefront error, and what sorts of systematics to the point spread function can be tolerated, given LSST's weak lensing mission.

Rasmussen, Andrew; Chang, C.; Kahn, S. M.; O'Connor, P.; Takacs, P.; Schindler, R.; Nordby, M.; LSST Camera Team

2009-01-01

235

In-focal-plane SQUID multiplexer  

International Nuclear Information System (INIS)

Superconducting quantum interference device (SQUID) multiplexers make it possible to build arrays of thousands of microcalorimeters and bolometers based on superconducting transition-edge sensors (TES) with a manageable number of readout channels. Previous to this work, TES arrays were multiplexed by extracting leads from each pixel to multiplexer filter and switching elements outside of the focal plane. As the number of pixels is increased in a close-packed array, it becomes difficult to route the leads to the multiplexer. We report on the development of an in-focal-plane SQUID multiplexer to solve this problem. In this circuit, the filter and switching elements associated with each pixel fit within the pixel area so that signals are multiplexed before being extracted from the focal plane. This in-focal-plane architecture will first be used in the SCUBA-2 instrument at the James Clerk Maxwell Telescope in 2006

236

Focal colors are universal after all  

Digital Repository Infrastructure Vision for European Research (DRIVER)

It is widely held that named color categories in the world's languages are organized around universal focal colors and that these focal colors tend to be chosen as the best examples of color terms across languages. However, this notion has been supported primarily by data from languages of industrialized societies. In contrast, recent research on a language from a nonindustrialized society has called this idea into question. We examine color-naming data from languages of 110 nonindustrialized...

Regier, Terry; Kay, Paul; Cook, Richard S.

2005-01-01

237

Surgery for drug-resistant focal epilepsy.  

Science.gov (United States)

During the colloquium on drug-resistant epilepsy (DRE) at National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore on August 16-18, 2013, a number of presentations were made on the surgically remediable lesional epilepsy syndromes, presurgical evaluation, surgical techniques, neuropathology of drug resistance focal epilepsy and surgical outcome. This pictorial essay with the illustrative case examples provides an overview of the various surgical techniques for the management of drug-resistant focal epilepsy. PMID:24791080

Rao, Malla Bhaskara; Arivazhagan, Arimappamagan; Sinha, Sanjib; Bharath, Rose Dawn; Mahadevan, Anita; Bhat, Maya; Satishchandra, Parthasarthy

2014-03-01

238

Focal lesions in the central nervous system  

International Nuclear Information System (INIS)

This report reviews the animal and human studies currently in progress at LBL with heavy-ion beams to induce focal lesions in the central nervous system, and discusses the potential future prospects of fundamental and applied brain research with heavy-ion beams. Methods are being developed for producing discrete focal lesions in the central nervous system using the Bragg ionization peak to investigate nerve pathways and neuroendocrine responses, and for treating pathological disorders of the brain

239

Focal Adhesion Kinase and Endothelial Cell Apoptosis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Focal adhesion kinase is a key component of cell-substratum adhesions, known as focal adhesion complexes. Growing evidence indicates that FAK is important in maintenance of normal cell survival and that disruption of FAK signaling results in loss of substrate adhesion and anoikis (apoptosis) of anchorage-dependent cells, such as endothelial cells. Basal FAK activity in non-stimulated endothelial cells is important in maintaining cell adhesion to integrins via PI3 kinase/Akt signaling. FAK act...

Lu, Qing; Rounds, Sharon

2011-01-01

240

Likelihood analysis of earthquake focal mechanism distributions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In our paper published earlier we discussed forecasts of earthquake focal mechanism and ways to test the forecast efficiency. Several verification methods were proposed, but they were based on ad-hoc, empirical assumptions, thus their performance is questionable. In this work we apply a conventional likelihood method to measure a skill of forecast. The advantage of such an approach is that earthquake rate prediction can in principle be adequately combined with focal mechanis...

Kagan, Y. Y.; Jackson, D. D.

2014-01-01

 
 
 
 
241

Carbamazepine, clonazepam and focal reflex proprioceptive seizures  

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We studied a 34-year-old man with focal tonic-clonic seizures sometimes elicited by some active postures of the right hand and evolving at times to secondary generalization. Treatment with carbamazepine (CBZ) in combination with parenteral diazepam induced both a dramatic increase of focal reflex proprioceptive seizures and choreoathetoid dyskinesias in the affected hand. CBZ was withdrawn and clonazepam (CZP) given 2 mg daily, with complete relief of seizures and choreoathetoid dyskinesias. ...

Sechi, Gianpietro; Corda, Davide; Deiana, Giovanni Andrea; Contu, Sabrina; Rosati, Giulio

2003-01-01

242

Transtendon rotator-cuff repair of partial-thickness articular surface tears can lead to medial rotator-cuff failure  

Directory of Open Access Journals (Sweden)

Full Text Available Tom C Woods,4 Michael J Carroll,1 Atiba A Nelson,2 Kristie D More,2 Randa Berdusco,1 Stephen Sohmer,3 Richard S Boorman,1,2 Ian KY Lo1,21Department of Surgery, 2Sport Medicine Centre, University of Calgary, Calgary, AB, Canada; 3Department of Orthopaedics, University of British Columbia, Vancouver, 4St Joseph's Hospital, Comox, BC, CanadaPurpose: The purpose of this study was to evaluate clinical and anatomic outcomes of patients following transtendon rotator-cuff repair of partial articular supraspinatus tendon avulsion (PASTA lesions.Patients and methods: Patients in the senior author's practice who had isolated PASTA lesions treated by transtendon rotator-cuff repair were included (n=8 and retrospectively reviewed. All patients were evaluated preoperatively and at a mean of 21.2 months (±9.7 months postoperatively using standardized clinical evaluation (physical exam, American Shoulder and Elbow Surgeons, and Simple Shoulder Test. All patients underwent postoperative imaging with a magnetic resonance imaging arthrogram.Results: There was a significant improvement in American Shoulder and Elbow Surgeons (42.7±17.5 to 86.9±25.2 and Simple Shoulder Test (4.6±3.2 to 10.1±3.8 scores from pre- to postoperative, respectively. Postoperative imaging demonstrated full-thickness medial cuff tearing in seven patients, and one patient with a persistent partial articular surface defect.Conclusion: Transtendon repair of PASTA lesions may lead to improvements in clinical outcome. However, postoperative imaging demonstrated a high incidence of full-thickness rotator-cuff defects following repair.Keywords: rotator cuff, PASTA lesion, transtendon repair

Woods TC

2014-06-01

243

Arf GTPase-activating Protein AGAP2 Regulates Focal Adhesion Kinase Activity and Focal Adhesion Remodeling*  

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Focal adhesions are specialized sites of cell attachment to the extracellular matrix where integrin receptors link extracellular matrix to the actin cytoskeleton, and they are constantly remodeled during cell migration. Focal adhesion kinase (FAK) is an important regulator of focal adhesion remodeling. AGAP2 is an Arf GTPase-activating protein that regulates endosomal trafficking and is overexpressed in different human cancers. Here we examined the regulation of the FA...

Zhu, Yunjuan; Wu, Yuanjun; Kim, Jae I.; Wang, Zhimin; Daaka, Yehia; Nie, Zhongzhen

2009-01-01

244

Nanosized fibers' effect on adult human articular chondrocytes behavior  

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Tissue engineering with chondrogenic cell based therapies is an expanding field with the intention of treating cartilage defects. It has been suggested that scaffolds used in cartilage tissue engineering influence cellular behavior and thus the long-term clinical outcome. The objective of this study was to assess whether chondrocyte attachment, proliferation and post-expansion re-differentiation could be influenced by the size of the fibers presented to the cells in a scaffold. Polylactic acid (PLA) scaffolds with different fiber morphologies were produced, i.e. microfiber (MS) scaffolds as well as nanofiber-coated microfiber scaffold (NMS). Adult human articular chondrocytes were cultured in the scaffolds in vitro up to 28 days, and the resulting constructs were assessed histologically, immunohistochemically, and biochemically. Attachment of cells and serum proteins to the scaffolds was affected by the architecture. The results point toward nano-patterning onto the microfibers influencing proliferation of the chondrocytes, and the overall 3D environment having a greater influence on the re-differentiation. In the efforts of finding the optimal scaffold for cartilage tissue engineering, studies as the current contribute to the knowledge of how to affect and control chondrocytes behavior. - Highlights: ? Chondrocyte behavior in nanofiber-coated microfiber versus microfiber scaffolds ? High porosity (> 90%) and large pore sizes (a few hundred ?m) of nanofibrous scaffolds ? Proliferation enhanced by presence of nanofibers ? Differentiation not significantly affected ? Cell attachment improved in presence of both nanofibers and serum.

Stenhamre, Hanna [Biopolymer Technology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg (Sweden); Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg (Sweden); Thorvaldsson, Anna, E-mail: anna.thorvaldsson@swerea.se [Biopolymer Technology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg (Sweden); Swerea IVF, Mölndal (Sweden); Enochson, Lars [Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg (Sweden); Walkenström, Pernilla [Swerea IVF, Mölndal (Sweden); Lindahl, Anders [Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg (Sweden); Brittberg, Mats [Cartilage Research Unit, University of Gothenburg, Department Orthopaedics, Kungsbacka Hospital, Kungsbacka (Sweden); Gatenholm, Paul [Biopolymer Technology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg (Sweden)

2013-04-01

245

Efeitos dos glicosaminoglicanos e sulfato de condroitina A sobre a cartilagem articular normal e com doença articular degenerativa em cães Glycosaminoglycans and chondroitin sulphate "A" effects on normal and osteoarthritic articular cartilage in dogs  

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Avaliaram-se os efeitos dos precursores dos glicosaminoglicanos (GAG) e do sulfato de condroitina A (SC) sobre a histomorfometria da cartilagem articular normal ou de cartilagem de cães com doença articular degenerativa (DAD) experimental. Os grupos experimentais constituíram-se de animais com articulação direita normal, que não foi submetida a procedimento cirúrgico, e com articulação esquerda osteoartrótica e que foi submetida à intervenção cirúrgica. Os grupos foram subdividi...

Vieira, N. T.; Melo, E. G.; Rezende, C. M. F.; Gomes, M. G.; Caldeira, F. M. C.; Jesus, M. C.

2010-01-01

246

Steroid-responsive focal epilepsy with focal dystonia accompanied by glutamate receptor delta2 antibody.  

Science.gov (United States)

This report describes a rare case presenting with focal epilepsy and focal dystonia associated with glutamate receptor ?2 antibody. The patient was a 47-year-old male patient with neurosyphilis. He presented with an intractable focal seizure spreading from the right arm, with dystonia of the left leg. The IgG antibody of glutamate receptor ?2 was detected. Ictal and interictal SPECT suggested focal epilepsy in the left frontal cortex. Antibiotic and antiepileptic drugs were ineffective, although steroid pulse therapy effectively diminished the patient's symptoms. Inflammatory mechanisms may have contributed to this disorder. PMID:22613698

Matsumoto, Hideyuki; Okabe, Shingo; Hirakawa-Yamada, Minako; Takahashi, Yukitoshi; Satoh, Noboru; Igeta, Yukifusa; Hashida, Hideji

2012-08-15

247

Relation between shape of the articular eminence and disc displacement in the temporomandibular joint  

International Nuclear Information System (INIS)

To investigate the hypothesis that the morphology of the articular eminence of the temporomandibular joint is a predisposing factor for disc displacement. MR images of 126 temporomandibular joints in 94 patients were analyzed to assess for morphology of the articular eminence and disc displacement. The displaced disc was further categorized as disc displacement with reduction (DDWR) and disc displacement without reduction (DDWOR). The morphology of the articular eminence was classified into four types; box, sigmoid, flattened, and deformed. The relationship between the four types of shape of the articular eminence and the two types of disc position was assessed. In the DDWR and DDWOR groups, the morphology of articular eminence were a box type in 40.5%, a sigmoid type in 30.2%, a flattened type in 24.6%, and a deformed type in 4.7%. The box type of the articular eminence were 34.3% in the DDWR group and 42.9% in the DDWOR group. The sigmoid type of the articular eminence were 34.3% in the DDWR group and 28.6% in the DDWOR group. The flattened type of the articular eminence were 28.6% in the DDWR group and 23.1% in the DDWOR group. The deformed type of the articular eminence were 2.9% in the DDWR group and 5.5% in the DDWOR group. Disc displacement in more likely to be found in the temporomandibular joints with a box-shaped articular eminence. It can be considered that shape of the articular eminence is related to the development of disc displacementnt of disc displacement

248

Relation between shape of the articular eminence and disc displacement in the temporomandibular joint  

Energy Technology Data Exchange (ETDEWEB)

To investigate the hypothesis that the morphology of the articular eminence of the temporomandibular joint is a predisposing factor for disc displacement. MR images of 126 temporomandibular joints in 94 patients were analyzed to assess for morphology of the articular eminence and disc displacement. The displaced disc was further categorized as disc displacement with reduction (DDWR) and disc displacement without reduction (DDWOR). The morphology of the articular eminence was classified into four types; box, sigmoid, flattened, and deformed. The relationship between the four types of shape of the articular eminence and the two types of disc position was assessed. In the DDWR and DDWOR groups, the morphology of articular eminence were a box type in 40.5%, a sigmoid type in 30.2%, a flattened type in 24.6%, and a deformed type in 4.7%. The box type of the articular eminence were 34.3% in the DDWR group and 42.9% in the DDWOR group. The sigmoid type of the articular eminence were 34.3% in the DDWR group and 28.6% in the DDWOR group. The flattened type of the articular eminence were 28.6% in the DDWR group and 23.1% in the DDWOR group. The deformed type of the articular eminence were 2.9% in the DDWR group and 5.5% in the DDWOR group. Disc displacement in more likely to be found in the temporomandibular joints with a box-shaped articular eminence. It can be considered that shape of the articular eminence is related to the development of disc displacement.

Lee, Heung Ki; Hwang, Eui Hwan; Lee, Sang Rae [Kyung Hee Univ. College of Dentistry, Seoul (Korea, Republic of)

2001-09-15

249

ROCK inhibitor prevents the dedifferentiation of human articular chondrocytes  

International Nuclear Information System (INIS)

Highlights: ? ROCK inhibitor stimulates chondrogenic gene expression of articular chondrocytes. ? ROCK inhibitor prevents the dedifferentiation of monolayer-cultured chondrocytes. ? ROCK inhibitor enhances the redifferentiation of cultured chondrocytes. ? ROCK inhibitor is useful for preparation of un-dedifferentiated chondrocytes. ? ROCK inhibitor may be a useful reagent for chondrocyte-based regeneration therapy. -- Abstract: Chondrocytes lose their chondrocytic phenotypes in vitro. The Rho family GTPase ROCK, involved in organizing the actin cytoskeleton, modulates the differentiation status of chondrocytic cells. However, the optimum method to prepare a large number of un-dedifferentiated chondrocytes is still unclear. In this study, we investigated the effect of ROCK inhibitor (ROCKi) on the chondrogenic property of monolayer-cultured articular chondrocytes. Human articular chondrocytes were subcultured in the presence or absence of ROCKi (Y-27632). The expression of chondrocytic marker genes such as SOX9 and COL2A1 was assessed by quantitative real-time PCR analysis. Cellular morphology and viability were evaluated. Chondrogenic redifferentiation potential was examined by a pellet culture procedure. The expression level of SOX9 and COL2A1 was higher in ROCKi-treated chondrocytes than in untreated cells. Chondrocyte morphology varied from a spreading form to a round shape in a ROCKi-dependent manner. In addition, ROCKi treatment stimulated the proliferation of chondrocytes. The deposition of safranin O-stained proteoglycans and type II collagen was highly detected in chondrogenic pellets derived from ROCKi-pretreated chondrocytes. Our results suggest that ROCKi prevents the dedifferentiation of monolayer-cultured chondrocytes, and may be a useful reagent to maintain chondrocytic phenotypes in vitro for chondrocyte-based regeneration therapy.

250

Rodent models for the study of articular fracture healing.  

Science.gov (United States)

The goal of this study was to document the healing time course and expression of ex vivo cell-based gene delivery in articular fracture models in the mouse and rat. Articular medial intercondylar femoral osteotomy was performed in the stifle (knee) joints of hairless immunocompetent mice and medial or lateral similar osteotomy was performed in athymic nude rats. Genetically modified cells expressing luciferase were delivered in a three-dimensional alginate matrix directly into the osteotomy site. Sensitivity of an in vivo imaging system to detect expression of luciferase was compared between rodents in this fracture model. Osteotomy healing was assessed using high-detail radiography, helical computed tomography (CT), high-field magnetic resonance imaging, and histology. The mouse model was less satisfactory because the small size of the murine femur made reliable assessment of fracture healing restricted to histopathology, and complications occurred in 11/24 mice (45.8%), most frequently transverse supracondylar femoral fracture postoperatively. Gene expression was inconsistently confirmed in mice in vivo for 11 days (p < .003). In rats, high-detail radiography and CT were used to assess osteotomy healing. Magnetic resonance imaging (4.7 T) in rats could produce three-dimensional images that would permit assessment of bone and cartilage, but was time-consuming and expensive. In rats, the only surgical complication, transverse femoral fracture, was reduced from 83.3% with the medial osteotomy to 0% with a lateral osteotomy. In vivo imaging confirmed gene expression in the alginate/cell constructs in rats for at least 4 days (p < .05). The nude rat model has the advantage of larger femora and the ability to implant xenograft cells. A lateral intercondylar osteotomy of the distal femur in the rat can be used to study the healing of articular fractures. PMID:17454393

Zachos, Terri A; Bertone, Alicia L; Wassenaar, Peter A; Weisbrode, Steven E

2007-01-01

251

ROCK inhibitor prevents the dedifferentiation of human articular chondrocytes  

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Highlights: Black-Right-Pointing-Pointer ROCK inhibitor stimulates chondrogenic gene expression of articular chondrocytes. Black-Right-Pointing-Pointer ROCK inhibitor prevents the dedifferentiation of monolayer-cultured chondrocytes. Black-Right-Pointing-Pointer ROCK inhibitor enhances the redifferentiation of cultured chondrocytes. Black-Right-Pointing-Pointer ROCK inhibitor is useful for preparation of un-dedifferentiated chondrocytes. Black-Right-Pointing-Pointer ROCK inhibitor may be a useful reagent for chondrocyte-based regeneration therapy. -- Abstract: Chondrocytes lose their chondrocytic phenotypes in vitro. The Rho family GTPase ROCK, involved in organizing the actin cytoskeleton, modulates the differentiation status of chondrocytic cells. However, the optimum method to prepare a large number of un-dedifferentiated chondrocytes is still unclear. In this study, we investigated the effect of ROCK inhibitor (ROCKi) on the chondrogenic property of monolayer-cultured articular chondrocytes. Human articular chondrocytes were subcultured in the presence or absence of ROCKi (Y-27632). The expression of chondrocytic marker genes such as SOX9 and COL2A1 was assessed by quantitative real-time PCR analysis. Cellular morphology and viability were evaluated. Chondrogenic redifferentiation potential was examined by a pellet culture procedure. The expression level of SOX9 and COL2A1 was higher in ROCKi-treated chondrocytes than in untreated cells. Chondrocyte morphology varied from a spreading form to a round shape in a ROCKi-dependent manner. In addition, ROCKi treatment stimulated the proliferation of chondrocytes. The deposition of safranin O-stained proteoglycans and type II collagen was highly detected in chondrogenic pellets derived from ROCKi-pretreated chondrocytes. Our results suggest that ROCKi prevents the dedifferentiation of monolayer-cultured chondrocytes, and may be a useful reagent to maintain chondrocytic phenotypes in vitro for chondrocyte-based regeneration therapy.

Matsumoto, Emi [Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikatacho, Kitaku, Okayama 700-8558 (Japan); Furumatsu, Takayuki, E-mail: matino@md.okayama-u.ac.jp [Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikatacho, Kitaku, Okayama 700-8558 (Japan); Kanazawa, Tomoko; Tamura, Masanori; Ozaki, Toshifumi [Department of Orthopaedic Surgery, Science of Functional Recovery and Reconstruction, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikatacho, Kitaku, Okayama 700-8558 (Japan)

2012-03-30

252

Manifestações articulares nas viroses exantemáticas Joint complaints in exanthematic diseases  

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Full Text Available A freqüência de manifestações articulares foi avaliada em 251 pacientes com diagnóstico clínico e laboratorial (detecção de IgM por ensaio imunoenzimático de virose exantemática. As artropatias (artralgia e/ou artrite foram mais observadas nos casos de dengue (49% e de rubéola (38,2% do que naqueles com parvovirose humana (30% e sarampo (28,1%. Com exceção do sarampo, as artropatias predominaram nos adultos (315 anos de idade, sendo tal diferença estatisticamente significativa. A ocorrência maior de artropatias em adultos foi mais evidente nos pacientes com parvovirose (75%, rubéola (65% e dengue (57,7% do que naqueles com sarampo (31%. As queixas articulares também predominaram nos pacientes do sexo feminino para todas as viroses avaliadas. Os resultados encontrados demonstram o freqüente acometimento articular nas doenças estudadas, e indicam a necessidade de comprovação laboratorial para o diagnóstico diferencial entre elas.The frequency of arthropathy was evaluated in 251 patients with clinical and serological diagnosis (specific IgM detection by enzyme immunoassay of exanthematic disease. Arthropathy (arthralgia and/or arthritis was more frequent in dengue fever (49% and rubella (38.2% cases than in human parvovirus (30% and measles (28.1% cases. Except for measles cases, joint complaints prevailed in adults (315 years of age and this difference was significant. The higher frequency of arthropathy in adults was more evident in human parvovirus (75%, rubella (65% and dengue fever (57.7% cases than in measles cases (31%. Arthropathy was also more frequent in females for all rash diseases studied. The results of this study showed the high occurrence of joint complaints in the diseases described here and the importance of laboratory confirmation for their differential diagnosis.

Solange Artimos de Oliveira

1999-04-01

253

Impact of therapeutic irradiation on healthy articular cartilage.  

Science.gov (United States)

Radiation-induced complications in bone and cartilage are of increasing concern due to potential long-term effects in cancer survivors. Healthy articular cartilage may be exposed to radiation during either chondrosarcoma treatment or in-field radiotherapy of tumors located in close proximity to articulation. Cartilage exposed to radiation undergoes bone differentiation and senescence, which can lead to painful and disabling sequelae that can impair patient quality of life. An understanding of the biological processes involved in healthy cartilage response to radiotherapy may not only optimize the delivery of therapeutic radiation but also reduce the risk of long-term sequelae in irradiated cartilage. Over the last few decades, radiobiology studies have focused primarily on signaling and repair of DNA damage pathways induced by ionizing radiation in immortalized cells under conditions dramatically different from human homeostasis. This research needs to be continued and broadened, since the range of normal tissue responses to radiation exposure is still not fully understood, despite being recognized as the major limiting factor in the rupture of tissue homeostasis after radiotherapy. Human articular cartilage is an avascular tissue with low intracellular oxygen levels and is comprised of a single cell lineage of chondrocytes embedded in a highly dense and structured extracellular matrix. These relatively unique features may impact inherent cell radiation sensitivity and suggests that canonical cell responses to ionizing radiation may not be applicable to articular cartilage. Despite the number of studies in this field, radiation-induced modifications of chondrocyte proteome remain unclear because of the dramatic variability in reported experimental conditions. In this review, we propose to introduce cartilage tissue physiology and microenvironment concepts, and then present a comprehensive synthesis of cartilage radiation biology. PMID:25587740

Saintigny, Yannick; Cruet-Hennequart, Séverine; Hamdi, Dounia Houria; Chevalier, François; Lefaix, Jean-Louis

2015-02-01

254

Multiple Requirements of the Focal Dermal Hypoplasia Gene Porcupine during Ocular Morphogenesis.  

Science.gov (United States)

Wnt glycoproteins control key processes during development and disease by activating various downstream pathways. Wnt secretion requires post-translational modification mediated by the O-acyltransferase encoded by the Drosophila porcupine homolog gene (PORCN). In humans, PORCN mutations cause focal dermal hypoplasia (FDH, or Goltz syndrome), an X-linked dominant multisystem birth defect that is frequently accompanied by ocular abnormalities such as coloboma, microphthalmia, or even anophthalmia. Although genetic ablation of Porcn in mouse has provided insight into the etiology of defects caused by ectomesodermal dysplasia in FDH, the requirement for Porcn and the actual Wnt ligands during eye development have been unknown. In this study, Porcn hemizygosity occasionally caused ocular defects reminiscent of FDH. Conditional inactivation of Porcn in periocular mesenchyme led to defects in mid- and hindbrain and in craniofacial development, but was insufficient to cause ocular abnormalities. However, a combination of conditional Porcn depletion in optic vesicle neuroectoderm, lens, and neural crest-derived periocular mesenchyme induced severe eye abnormalities with high penetrance. In particular, we observed coloboma, transdifferentiation of the dorsal and ventral retinal pigment epithelium, defective optic cup periphery, and closure defects of the eyelid, as well as defective corneal morphogenesis. Thus, Porcn is required in both extraocular and neuroectodermal tissues to regulate distinct Wnt-dependent processes during morphogenesis of the posterior and anterior segments of the eye. PMID:25451153

Bankhead, Elizabeth J; Colasanto, Mary P; Dyorich, Kayla M; Jamrich, Milan; Murtaugh, L Charles; Fuhrmann, Sabine

2015-01-01

255

A concurrent computer aided detection (CAD) tool for articular cartilage disease of the knee on MR imaging using active shape models  

Science.gov (United States)

Osteoarthritis (OA) is the most common form of arthritis and a major cause of morbidity affecting millions of adults in the US and world wide. In the knee, OA begins with the degeneration of joint articular cartilage, eventually resulting in the femur and tibia coming in contact, and leading to severe pain and stiffness. There has been extensive research examining 3D MR imaging sequences and automatic/semi-automatic techniques for 2D/3D articular cartilage extraction. However, in routine clinical practice the most popular technique still remain radiographic examination and qualitative assessment of the joint space. This may be in large part because of a lack of tools that can provide clinically relevant diagnosis in adjunct (in near real time fashion) with the radiologist and which can serve the needs of the radiologists and reduce inter-observer variation. Our work aims to fill this void by developing a CAD application that can generate clinically relevant diagnosis of the articular cartilage damage in near real time fashion. The algorithm features a 2D Active Shape Model (ASM) for modeling the bone-cartilage interface on all the slices of a Double Echo Steady State (DESS) MR sequence, followed by measurement of the cartilage thickness from the surface of the bone, and finally by the identification of regions of abnormal thinness and focal/degenerative lesions. A preliminary evaluation of CAD tool was carried out on 10 cases taken from the Osteoarthritis Initiative (OAI) database. When compared with 2 board-certified musculoskeletal radiologists, the automatic CAD application was able to get segmentation/thickness maps in little over 60 seconds for all of the cases. This observation poses interesting possibilities for increasing radiologist productivity and confidence, improving patient outcomes, and applying more sophisticated CAD algorithms to routine orthopedic imaging tasks.

Ramakrishna, Bharath; Saiprasad, Ganesh; Safdar, Nabile; Siddiqui, Khan; Chang, Chein-I.; Siegel, Eliot

2008-03-01

256

Focal thyroid inferno” on color Doppler ultrasonography: A specific feature of focal Hashimoto's thyroiditis  

International Nuclear Information System (INIS)

Purpose: To evaluate color-Doppler features predictive of focal Hashimoto's thyroiditis. Materials and methods: A total of 521 patients with 561 thyroid nodules that underwent surgeries or gun biopsies were included in this study. These nodules were divided into three groups: focal Hashimoto's thyroiditis (104 nodules in 101 patients), benignity other than focal Hashimoto's thyroiditis (73 nodules in 70 patients), and malignancy (358 nodules in 350 patients). On color Doppler sonography, four vascularity types were determined as: hypovascularity, marked internal flow, marked peripheral flow and focal thyroid inferno. The ?2 test was performed to seek the potential vascularity type with the predictive ability of certain thyroid pathology. Furthermore, the gray-scale features of each nodule were also studied. Results: The vascularity type I (hypovascularity) was more often seen in focal Hashimoto's thyroiditis than other benignity and malignancy (46% vs. 20.5% and 19%). While the type II (marked internal flow) showed the opposite tendency (26.9% [focal Hashimoto's thyroiditis] vs. 45.2% [other benignity] and 52.8% [malignancy]). However, type III (marked peripheral flow) was unable to predict any thyroid pathology. Importantly, type IV (focal thyroid inferno) was exclusive to focal Hashimoto's thyroiditis. All 8 type IV nodules appeared to be solid, hypoechoic, and well-defined. Using “focal thyroid inferno” as an indicator of FHT, the diagnostic sensitivity and specificity were 7.7% and 100% respectively. Conclusions: The vascularity type of “focal thyroid inferno” is specific for focal Hashimoto thyroiditis. Recognition of this particular feature may avoid unnecessary interventional procedures for some solid hypoechoic thyroid nodules suspicious of malignancy.

257

Effect of passive motion on articular cartilage in rat osteoarthritis.  

Science.gov (United States)

The aim of the present study was to investigate the effect of moderate passive motion on articular cartilage in osteoarthritis (OA) caused by knee fracture. Sprague-Dawley rats (age, 8 weeks) with knee fractures were used to construct rat knee early- and middle-stage OA models. The stages were fixed for three and six weeks, with 20 rats analyzed at each stage. The experimental groups were exercised daily for 15 m/min with a specified duration. Following the completion of exercise, the effects of proper passive motion on cartilage thickness, the Mankin rating, cartilage collagen matrix, proteoglycan content and the morphological structure of the cartilage in the rat OA models were measured at the various degenerative stages caused by knee fracture. The proteoglycan content of the cartilage matrix, type II collagen fibers and the number of cartilage cells undergoing apoptosis were semiquantified. For early- and middle-stage OA, the cartilage layers in the three- or six-week experimental groups were significantly thicker and the levels of proteoglycans and type II collagen fibers in the weight-bearing area of the cartilage were significantly higher when compared with the control groups (P<0.05). In addition, the Mankin ratings were lower and ligament tension was increased when compared with the control group (P<0.05). In the early-stage OA group, significantly decreased apoptotic rates (P<0.05) were observed in the three- and six-week experimental groups, however, no significant decrease was observed in the middle-stage OA group. In the early-stage OA rats, the thickness of the cartilage layer, as well as the levels of proteoglycans and type II collagen fibers, in the six-week experimental group, were significantly higher compared with the control and three-week subgroups, and a decreased apoptotic rate was observed (P<0.05). In the six-week experimental middle-stage OA group, significant differences were observed in the content of proteoglycans and type II collagen fibers when compared with the control group, but not when compared with the three-week experimental group. Therefore, proper passive motion can repair and improve the metabolism of chondrocytes and delay the degenerative progress of articular cartilage in OA caused by knee fracture. However, for middle-stage OA, passive motion exhibits no significant repairing effect on the articular cartilage. This therapy increases the levels of proteoglycans and collagen fibers by reducing their decomposition, thereby improving the strength of the articular ligament and the stability of articulation. PMID:25009586

Qian, Jie; Liang, Jun; Wang, Yubin; Wang, Huifang

2014-08-01

258

Quantitative magnetic resonance imaging of articular cartilage in osteoarthritis  

Directory of Open Access Journals (Sweden)

Full Text Available Magnetic resonance imaging of articular cartilage has recently been recognized as a tool for the characterization of cartilage morphology, biochemistry and function. In this paper advancements in cartilage imaging, computation of cartilage volume and thickness, and measurement of relaxation times (T2 and T1? are presented. In addition, the delayed uptake of Gadolinium DTPA as a marker of proteoglycan depletion is also reviewed. The cross-sectional and longitudinal studies using these imaging techniques show promise for cartilage assessment and for the study of osteoarthritis.

G Blumenkrantz

2007-05-01

259

Fibroma aponeurótico calcificante intra articular. Presentación de un caso.  

Directory of Open Access Journals (Sweden)

Full Text Available El fibroma aponeurótico juvenil es un tumor infrecuente del tejido blando que se localiza con mayor periodicidad en niños y adolescentes en la región distal de las extremidades, aunque se reportan casos en otras edades y localización. Se presenta un paciente de 18 años de edad, masculino con fibroma aponeurótico calcificante en la rodilla derecha intra articular, con una localización poco común. El diagnóstico se realizó por exéresis quirúrgica del tumor. Se hace referencia al cuadro clínico, terapéutica efectuada y seguimiento por 3 años. Se revisó literatura actualizada referente al tema. Por ser un caso infrecuente se decide su publicación.

Niurka Rabelo Aday

2010-02-01

260

Production of interleukin-1 receptor antagonist by human articular chondrocytes.  

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Interleukin-1 receptor antagonist (IL-1Ra) is a natural IL-1 inhibitor possessing anti-inflammatory properties. IL-1Ra is produced as different isoforms, one secreted (sIL-1Ra) and three intracellular (icIL-1Ra1, icIL-1Ra2 and icIL-1Ra3), derived from the same gene. We examined the production of IL-1Ra species by cultured human articular chondrocytes in response to various cytokines. The levels of IL-1Ra were undetectable in culture supernatants of untreated cells, but were significantly incr...

Palmer, Gaby; Guerne, Pierre-andre?; Mezin, Franc?oise; Maret, Michel; Guicheux, Je?ro?me; Goldring, Mary; Gabay, Cem

2002-01-01

 
 
 
 
261

Production of interleukin-1 receptor antagonist by human articular chondrocytes  

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Interleukin-1 receptor antagonist (IL-1Ra) is a natural IL-1 inhibitor possessing anti-inflammatory properties. IL-1Ra is produced as different isoforms, one secreted (sIL-1Ra) and three intracellular (icIL-1Ra1, icIL-1Ra2 and icIL-1Ra3), derived from the same gene. We examined the production of IL-1Ra species by cultured human articular chondrocytes in response to various cytokines. The levels of IL-1Ra were undetectable in culture supernatants of untreated cells, but were significantly incr...

Palmer, Gaby; Guerne, Pierre-andre; Mezin, Francoise; Maret, Michel; Guicheux, Jerome; Goldring, Mary B.; Gabay, Cem

2002-01-01

262

Listeria monocytogenes septic arthritis following intra-articular yttrium-90 therapy.  

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Listeria monocytogenes is a rare cause of septic arthritis, which usually occurs in a host compromised by systemic illness. Intra-articular irradiation with yttrium-90 is generally free of complication. We report a case of intra-articular sepsis of the knee joint by Listeria monocytogenes acquired under unusual circumstances.

Wilson, A. P.; Prouse, P. J.; Gumpel, J. M.

1984-01-01

263

I Focalize, You Focalize, We All Focalize Together: Audience Participation in Persepolis  

Directory of Open Access Journals (Sweden)

Full Text Available

Abstract (E: This article combines theories of cognition and empathy with focalization theory to examine how and why different forms of audience engagement in fictional worlds are cued. The article argues that critics should examine the differences between engagement that encourages audiences to apply their own frames to the world presented and type engagement cued by means of point-of-view shots and close-ups of facial expressions.

Abstract (F: Cet article combine les théories de la cognition et de l’empathie avec la théorie de la focalisation afin d’analyser comment et pourquoi certaines œuvres construisent la manière dont le public est invité à s’investir dans des mondes fictionnels. Il défend l’idée que les critiques devraient examiner avant tout les différences entre un type d’investissement qui encourage les publics à appliquer leurs propres schémas de référence au monde de la fiction et un type d’investissement qui passe surtout par des techniques de point de vue et de plans rapprochés d’expressions faciles.

Lizzie Nixon

2010-06-01

264

Focal foveal atrophy of unknown etiology: Clinical pictures and possible underlying causes.  

Science.gov (United States)

BACKGROUND/PURPOSE: Focal foveal atrophy is defined as the presence of a small, focal, ill-defined, hypopigmented foveal or juxtafoveal lesion, with the remaining retina unaffected. The purpose of this study was to report the clinical characteristics and optical coherence tomography (OCT) in patients with focal foveal atrophy of unknown etiology. METHODS: The study was a retrospective observational case series. Data collected included complete ocular examination results for best corrected visual acuity (BCVA), ophthalmoscopy, fundus photography, fluorescein angiography, color sense discrimination tests, visual field tests, and OCT examinations. RESULTS: Twenty-three eyes in 21 patients were examined. The mean patient age was 49.2 ± 15.4 years. The mean BCVA was 20/25. The 21 patients were divided into three groups according to OCT results. Group 1 eyes (n = 10) had intact inner and outer hyperreflective layers (HRLs), with the signal of the inner HRL corresponding to the junction between the inner and outer photoreceptor segments and the outer HRL corresponding to the retinal pigment epithelium (RPE). Group 2 eyes (n = 9) had small hyporeflective defects with defects in the inner HRL at the fovea but an intact outer HRL. Group 3 eyes (n = 4) had small hyporeflective defects in both the inner and outer HRLs at the fovea. Groups 3 eyes had significantly lower visual acuity compared to Group 1 eyes and Group 2 eyes. There was no significant difference in visual acuity between Group 1 and Group 2 eyes. There were no significant differences among the groups with respect to color vision or foveal thickness. CONCLUSION: This is the first report of clinical presentations for patients with focal foveal atrophy of unknown etiology. OCT aided in the diagnosis and assessment of the degree of retinal structural abnormalities, but the real etiology of foveal atrophy remains unclear. PMID:23602019

Kao, Tzu-Yun; Chen, Muh-Shy; Jou, Jieh-Ren; Lin, Chang-Ping; Tsai, Tzu-Hsun; Ho, Tzyy-Chang

2013-04-17

265

Birth Defects Research and Tracking  

Science.gov (United States)

... serious birth defects of the brain and spine (neural tube defects). For this reason, all women who can become ... serious birth defects of the brain and spine (neural tube defects), some heart defects , and other birth defects. Poor ...

266

Arf GTPase-activating Protein AGAP2 Regulates Focal Adhesion Kinase Activity and Focal Adhesion Remodeling*  

Science.gov (United States)

Focal adhesions are specialized sites of cell attachment to the extracellular matrix where integrin receptors link extracellular matrix to the actin cytoskeleton, and they are constantly remodeled during cell migration. Focal adhesion kinase (FAK) is an important regulator of focal adhesion remodeling. AGAP2 is an Arf GTPase-activating protein that regulates endosomal trafficking and is overexpressed in different human cancers. Here we examined the regulation of the FAK activity and the focal adhesion remodeling by AGAP2. Our results show that FAK binds the pleckstrin homology domain of AGAP2, and the binding is independent of FAK activation following epidermal growth factor receptor stimulation. Overexpression of AGAP2 augments the activity of FAK, and concordantly, the knockdown of AGAP2 expression with RNA interference attenuates the FAK activity stimulated by epidermal growth factor or platelet-derived growth factor receptors. AGAP2 is localized to the focal adhesions, and its overexpression results in dissolution of the focal adhesions, whereas knockdown of its expression stabilizes them. The AGAP2-induced dissolution of the focal adhesions is independent of its GTPase-activating protein activity but may involve its N-terminal G protein-like domain. Our results indicate that AGAP2 regulates the FAK activity and the focal adhesion disassembly during cell migration. PMID:19318351

Zhu, Yunjuan; Wu, Yuanjun; Kim, Jae I.; Wang, Zhimin; Daaka, Yehia; Nie, Zhongzhen

2009-01-01

267

Arf GTPase-activating protein AGAP2 regulates focal adhesion kinase activity and focal adhesion remodeling.  

Science.gov (United States)

Focal adhesions are specialized sites of cell attachment to the extracellular matrix where integrin receptors link extracellular matrix to the actin cytoskeleton, and they are constantly remodeled during cell migration. Focal adhesion kinase (FAK) is an important regulator of focal adhesion remodeling. AGAP2 is an Arf GTPase-activating protein that regulates endosomal trafficking and is overexpressed in different human cancers. Here we examined the regulation of the FAK activity and the focal adhesion remodeling by AGAP2. Our results show that FAK binds the pleckstrin homology domain of AGAP2, and the binding is independent of FAK activation following epidermal growth factor receptor stimulation. Overexpression of AGAP2 augments the activity of FAK, and concordantly, the knockdown of AGAP2 expression with RNA interference attenuates the FAK activity stimulated by epidermal growth factor or platelet-derived growth factor receptors. AGAP2 is localized to the focal adhesions, and its overexpression results in dissolution of the focal adhesions, whereas knockdown of its expression stabilizes them. The AGAP2-induced dissolution of the focal adhesions is independent of its GTPase-activating protein activity but may involve its N-terminal G protein-like domain. Our results indicate that AGAP2 regulates the FAK activity and the focal adhesion disassembly during cell migration. PMID:19318351

Zhu, Yunjuan; Wu, Yuanjun; Kim, Jae I; Wang, Zhimin; Daaka, Yehia; Nie, Zhongzhen

2009-05-15

268

Anticuerpo anticitrulina y manifestaciones extra articulares en artritis reumatoidea / Anticitrulin antibody and the extra-articular manifestations in rheumatoid arthritis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: Spanish Abstract in spanish Los pacientes con artritis reumatidea (AR) pueden desarrollar manifestaciones extra articulares (MExA), relacionadas a su morbi-mortalidad. Los anticuerpos anti-péptidos citrulinados cíclicos (ACCP) son específicos para la AR y estan relacionados con el daño articular; y podrían tener rol patogénico [...] en las MExA. Nuestro objetivo fue determinar la relación entre los anticuerpos ACCP y MExA en pacientes con AR. Se incluyeron 74 pacientes con diagnóstico de AR (ACR 1987) mayores de 18 años, de más de 6 meses de evolución, con MExA, y un control apareado por sexo y edad sin MExA por cada paciente. Las variables demográficas, clínicas y de laboratorio se compararon con test t, chi cuadrado o Mann-Whitney. Se realizó análisis multivariado; p ? 0.05. Los pacientes con MExA presentaron mayor título de anticuerpo ACCP (116 vs. 34, p Abstract in english A large proportion of rheumatoid arthritis (RA) patients develop extra-articular manifestations (EAM), which are associated with morbidity and early mortality. Anti cyclic citrullinated peptide (ACCP) antibody has proven to be highly specific for the diagnosis of RA, associated with severe joint dam [...] age and may have some role in the pathogenesis of EAM. The aim of this study was to determine the relationship between ACCP antibody and the presence of EAM in RA patients. Seventy four RA patients (ACR 1987) with EAM, > 18 years, more than 6 months duration were included, and an EAM free control, matched by sex and age, for each patient. Demographic, clinical and laboratory variables were compared using t-test, chi-square or Mann-Whitney test. Multivariate analysis was performed: p ? 0.05. Patients with EAM presented a greater value of ACCP antibody (116 vs. 34, p

María Jezabel, Haye Salinas; Soledad, Retamozo; Lorena, Vetorazzi; Natalia, Peano; Patricia Ericka, Díaz Cuiza; María Sol, Castaños Menescardi; Evangelina María, Miretti; Laura Mariela, Encinas; Ana Cecilia, Álvarez; Verónica, Saurit; Alejandro, Alvarellos; Francisco, Caeiro.

2013-02-01

269

Prenatal sonographic diagnosis of focal musculoskeletal anomalies  

International Nuclear Information System (INIS)

Focal musculoskeletal anomalies vary, and can manifest as part of a syndrome or be accompanied by numerous other conditions such as genetic disorders, karyotype abnormalities, central nervous system anomalies and other skeletal anomalies, lsolated focal musculoskeletal anomaly does, however, also occur; its early prenatal diagnosis is important in deciding prenatal care, and also helps in counseling parents about the postnatal effects of numerous possible associated anomalies. We have encountered 50 cases involving focal musculoskeletal anomalies, including total limb dysplasia [radial ray abnormality (n=3), mesomelic dysplasia (n=1)]; anomalies of the hand [polydactyly (n=8), syndactyly (n=3), ectrodactyly (n=1), clinodactyly (n=6), clenched hand (n=5)]; anomalies of the foot [clubfoot (n=10), rockerbottom foot (n=5), sandal gap deformity (n=1), curly toe (n=2)]; amniotic band syndrome (n=3); and anomalies of the focal spine [block vertebra (n=1), hemivertebra (n=1)]. Among these 50 cases, five [polydactyly (n=1), syndactyly (n=2) and curly toe (n=2) were confirmed by postnatal physical evaluation, two (focal spine anomalies) were diagnosed after postnatal radiologic examination, and the remaining 43 were proven at autopsy. For each condition, we describe the prenatal sonographic findings, and include a brief review

270

Multiphysical modelling of fluid transport through osteo-articular media  

Directory of Open Access Journals (Sweden)

Full Text Available In this study, a multiphysical description of fluid transport through osteo-articular porous media is presented. Adapted from the model of Moyne and Murad, which is intended to describe clayey materials behaviour, this multiscale modelling allows for the derivation of the macroscopic response of the tissue from microscopical information. First the model is described. At the pore scale, electrohydrodynamics equations governing the electrolyte movement are coupled with local electrostatics (Gauss-Poisson equation, and ionic transport equations. Using a change of variables and an asymptotic expansion method, the macroscopic description is carried out. Results of this model are used to show the importance of couplings effects on the mechanotransduction of compact bone remodelling.Neste estudo uma descrição multifísica do transporte de fluidos em meios porosos osteo articulares é apresentada. Adaptado a partir do modelo de Moyne e Murad proposto para descrever o comportamento de materiais argilosos a modelagem multiescala permite a derivação da resposta macroscópica do tecido a partir da informação microscópica. Na primeira parte o modelo é apresentado. Na escala do poro as equações da eletro-hidrodinâmica governantes do movimento dos eletrolitos são acopladas com a eletrostática local (equação de Gauss-Poisson e as equações de transporte iônico. Usando uma mudança de variáveis e o método de expansão assintótica a derivação macroscópica é conduzida. Resultados do modelo proposto são usados para salientar a importância dos efeitos de acoplamento sobre a transdução mecânica da remodelagem de ossos compactados.

Thibault Lemaire

2010-03-01

271

Resurfacing damaged articular cartilage to restore compressive properties.  

Science.gov (United States)

Surface damage to articular cartilage is recognized as the initial underlying process causing the loss of mechanical function in early-stage osteoarthritis. In this study, we developed structure-modifying treatments to potentially prevent, stabilize or reverse the loss in mechanical function. Various polymers (chondroitin sulfate, carboxymethylcellulose, sodium hyaluronate) and photoinitiators (riboflavin, irgacure 2959) were applied to the surface of collagenase-degraded cartilage and crosslinked in situ using UV light irradiation. While matrix permeability and deformation significantly increased following collagenase-induced degradation of the superficial zone, resurfacing using tyramine-substituted sodium hyaluronate and riboflavin decreased both values to a level comparable to that of intact cartilage. Repetitive loading of resurfaced cartilage showed minimal variation in the mechanical response over a 7 day period. Cartilage resurfaced using a low concentration of riboflavin had viable cells in all zones while a higher concentration resulted in a thin layer of cell death in the uppermost superficial zone. Our approach to repair surface damage initiates a new therapeutic advance in the treatment of injured articular cartilage with potential benefits that include enhanced mechanical properties, reduced susceptibility to enzymatic degradation and reduced adhesion of macrophages. PMID:25468298

Grenier, Stephanie; Donnelly, Patrick E; Gittens, Jamila; Torzilli, Peter A

2015-01-01

272

Radiation synovectomy stimulates glycosaminoglycan synthesis by normal articular cartilage  

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Radiation synovectomy has been considered a therapeutic alternative to surgical synovectomy. Whether intraarticular irradiation affects the composition or biochemistry, and therefore the biomechanical properties, of normal articular cartilage has not been established. In the present study, yttrium 90 silicate was injected into one knee of nine normal adult dogs, and three other dogs received nonradioactive yttrium silicate. When the animals were killed 4 to 13 weeks after the injection, synovium from the irradiated knees showed areas of necrosis and fibrosis. Up to 29% less hyaluronate was synthesized in vitro by the synovial intima from irradiated knees than by the intima from the contralateral knees (mean difference 18%). Morphologic abnormalities were not observed in articular cartilage from either the irradiated or control knees, nor did the water content or concentrations of uronic acid or DNA in cartilage from the irradiated knees differ from that in cartilage from the contralateral knees. However, net /sup 35/SO/sub 4/-labeled glycosaminoglycan synthesis in organ cultures of cartilage from irradiated knees was increased (mean difference 21%, p = 0.03) in comparison with that in cultures of contralateral knee cartilage.

Myers, S.L.; Slowman, S.D.; Brandt, K.D.

1989-07-01

273

Radiation synovectomy stimulates glycosaminoglycan synthesis by normal articular cartilage  

International Nuclear Information System (INIS)

Radiation synovectomy has been considered a therapeutic alternative to surgical synovectomy. Whether intraarticular irradiation affects the composition or biochemistry, and therefore the biomechanical properties, of normal articular cartilage has not been established. In the present study, yttrium 90 silicate was injected into one knee of nine normal adult dogs, and three other dogs received nonradioactive yttrium silicate. When the animals were killed 4 to 13 weeks after the injection, synovium from the irradiated knees showed areas of necrosis and fibrosis. Up to 29% less hyaluronate was synthesized in vitro by the synovial intima from irradiated knees than by the intima from the contralateral knees (mean difference 18%). Morphologic abnormalities were not observed in articular cartilage from either the irradiated or control knees, nor did the water content or concentrations of uronic acid or DNA in cartilage from the irradiated knees differ from that in cartilage from the contralateral knees. However, net 35SO4-labeled glycosaminoglycan synthesis in organ cultures of cartilage from irradiated knees was increased (mean difference 21%, p = 0.03) in comparison with that in cultures of contralateral knee cartilage

274

Articular pharmacokinetics of protein-bound antirheumatic agents.  

Science.gov (United States)

By what mechanism do nonsteroidal anti-inflammatory drugs (NSAIDs) move from plasma into synovial fluid and back, and how does binding to plasma albumin in vitro relate to articular transport in vivo? To evaluate these issues, concurrent plasma and synovial fluid data of 8 different NSAIDs from 10 single-dose trials were analysed by a simple compartmental model incorporating intra-articular volume, synovial plasma flow rates and protein transport. All pharmacological and physiological data were taken from published studies of chronic knee effusions in patients with rheumatoid arthritis. The analysis shows that these protein-bound NSAIDs readily leave the vasculature and enter synovial fluid during each transit of synovial microvessels. The mean rate of transport, 0.23 min-1, is consistent with passive diffusion at rates far in excess of those attributable to movement of albumin-bound drug or of the small, free-drug fraction found by equilibrium dialysis. These findings are explained by association and dissociation of NSAIDs and albumin that occur far more rapidly than vascular transit. Ongoing dissociation makes bound drug available for transvascular exchange and thereby diminishes the pharmacokinetic significance of binding data obtained in vitro. PMID:8261716

Simkin, P A; Wu, M P; Foster, D M

1993-10-01

275

Gene expression profile of the cartilage tissue spontaneously regenerated in vivo by using a novel double-network gel: Comparisons with the normal articular cartilage  

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Full Text Available Abstract Background We have recently found a phenomenon that spontaneous regeneration of a hyaline cartilage-like tissue can be induced in a large osteochondral defect by implanting a double-network (DN hydrogel plug, which was composed of poly-(2-Acrylamido-2-methylpropanesulfonic acid and poly-(N, N'-Dimetyl acrylamide, at the bottom of the defect. The purpose of this study was to clarify gene expression profile of the regenerated tissue in comparison with that of the normal articular cartilage. Methods We created a cylindrical osteochondral defect in the rabbit femoral grooves. Then, we implanted the DN gel plug at the bottom of the defect. At 2 and 4 weeks after surgery, the regenerated tissue was analyzed using DNA microarray and immunohistochemical examinations. Results The gene expression profiles of the regenerated tissues were macroscopically similar to the normal cartilage, but showed some minor differences. The expression degree of COL2A1, COL1A2, COL10A1, DCN, FMOD, SPARC, FLOD2, CHAD, CTGF, and COMP genes was greater in the regenerated tissue than in the normal cartilage. The top 30 genes that expressed 5 times or more in the regenerated tissue as compared with the normal cartilage included type-2 collagen, type-10 collagen, FN, vimentin, COMP, EF1alpha, TFCP2, and GAPDH genes. Conclusions The tissue regenerated by using the DN gel was genetically similar but not completely identical to articular cartilage. The genetic data shown in this study are useful for future studies to identify specific genes involved in spontaneous cartilage regeneration.

Kurokawa Takayuki

2011-09-01

276

Birth Defects Diagnosis  

Science.gov (United States)

... a baby with certain birth defects, such as neural tube defects or chromosomal disorders such as Down syndrome. It ... an opening in the tissue, such as a neural tube defect (anencephaly or spina bifida), or a body wall ...

277

Extended defects in Germanium  

CERN Document Server

Intends to provide a fundamental understanding of the extended-defect formation during Ge materials and device processing, providing ways to distinguish harmful from less detrimental defects and should point out ways for defect engineering and control.

Osgood, R M

2008-01-01

278

Solid-state curved focal plane arrays  

Science.gov (United States)

The present invention relates to curved focal plane arrays. More specifically, the present invention relates to a system and method for making solid-state curved focal plane arrays from standard and high-purity devices that may be matched to a given optical system. There are two ways to make a curved focal plane arrays starting with the fully fabricated device. One way, is to thin the device and conform it to a curvature. A second way, is to back-illuminate a thick device without making a thinned membrane. The thick device is a special class of devices; for example devices fabricated with high purity silicon. One surface of the device (the non VLSI fabricated surface, also referred to as the back surface) can be polished to form a curved surface.

Nikzad, Shouleh (Inventor); Hoenk, Michael (Inventor); Jones, Todd (Inventor)

2010-01-01

279

Differences between diffuse and focal autoimmune pancreatitis  

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AIM: To investigate differences in clinical features between diffuse- and focal-type autoimmune pancreatitis (AIP). METHODS: Based on radiological findings by computed tomography and/or magnetic resonance imaging, we divided 67 AIP patients into diffuse type (D type) and focal type (F type). We further divided F type into head type (H type) and body and/or tail type (B/T type) according to the location of enlargement. Finally, we classified the 67 AIP patients into three groups: D type, H typ...

Sawako Kuruma; Terumi Kamisawa; Seiichi Hara; Taku Tabata; Yoshihiko Inaba; Kensuke Takuma

2012-01-01

280

Ambroxol-induced focal epileptic seizure.  

Science.gov (United States)

It is well known that in epileptic patients some compounds and different drugs used for the treatment of comorbidities can facilitate or provoke seizures, this evidence regarding a wide spectrum of pharmacological categories. The potential facilitating factors usually include direct toxic effects or pharmacological interactions of either active ingredients or excipients. We report the case of a patient with drug-resistant epilepsy who experienced focal epileptic seizures, easily and constantly reproducible, after each administration of a cough syrup. This is, to our knowledge, the first electroencephalogram-documented case of focal epileptic seizures induced by cough syrup containing ambroxol as active ingredient. PMID:24824664

Lapenta, Leonardo; Morano, Alessandra; Fattouch, Jinane; Casciato, Sara; Fanella, Martina; Giallonardo, Anna Teresa; Di Bonaventura, Carlo

2014-01-01

 
 
 
 
281

Focal splenic masses of the extramedullary hematopoiesis  

International Nuclear Information System (INIS)

Full text: Extramedullary hematopoiesis arises from pleuripotential stem cells distributed throughout the body. It is most common in patients with congenital hemolytic anemia, such as thalassemia, sickle cell anemia and hereditary spherocytosis as a response to ineffective red blood cell formation. Although microscopic foci of Extramedullary hematopoiesis are commonly seen in the spleen and liver parenchyma, focal mass-like lesion of extramedullary hematopoiesis in the liver and spleen are rare. We report a case of intrasplenic focal extramedullary hematopoiesis lesions and the imaging features of extramedullary hematopoiesis on computed tomography and magnetic resonance imaging. Extramedullary hematopoiesis should always be considered as a diagnosis in a patient with a known hematological disorder

282

Focal seizures and non-ketotic hyperglycaemia.  

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The clinical features of seven patients with non-ketotic hyperglycaemia who developed focal seizures are presented. All patients were alert except one who was mildly confused. Glucose values varied from 17.8 to 55.1 mmol/l, while calculated osmolarity values were elevated in all cases to a mild or moderate extent (299.1 to 346.5 mmol/l). In three cases diabetes mellitus was a new diagnosis. Four patients had recurrent episodes of focal seizures when glycaemic control was lost. Movement induce...

Hennis, A.; Corbin, D.; Fraser, H.

1992-01-01

283

Spheric long-focal-depth lens  

Science.gov (United States)

Spheric lens designed by nonlinear phase fitting method is proposed to duplicate the performance of logarithmic axicon, which can obtain a beam with long-focal-depth, small focal spot and side lobe. Moreover, the spheric lens is easier and less expensive for manufacture than logarithmic or aspherical elements. Based on this method, a simple lens is designed for the plasma diagnostic system in inertial confinement fusion. It is verified through Fresnel diffraction integral and an initial experiment that the performance of the lens can satisfy the requirements of the plasma measurements.

Wen, Shenglin; Su, Jingqin; Dong, Jun; Gao, Fuhua; Guo, Yongkang; Zhang, YiXiao

2007-10-01

284

Crystal diffraction lens with variable focal length  

Science.gov (United States)

A method and apparatus for altering the focal length of a focusing element of one of a plurality of pre-determined focal lengths by changing heat transfer within selected portions of the element by controlled quantities is disclosed. Control over heat transfer is accomplished by manipulating one or more of a number of variables, including: the amount of heat or cold applied to surfaces; type of fluids pumped through channels for heating and cooling; temperatures, directions of flow and rates of flow of fluids; and placement of channels. 19 figures.

Smither, R.K.

1991-04-02

285

O gel de plasma rico em plaquetas propicia a regeneração da cartilagem articular do joelho de ovelhas / Platelet-rich plasma gel promotes regeneration of articular cartilage in knees of sheeps  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Avaliar a regeneração da cartilagem articular em defeitos osteocondrais do joelho induzidos pelo plasma rico em plaquetas (PRP) autógeno. MÉTODOS: Defeitos osteocondrais produzidos no sulco troclear de ambos os joelhos de dez ovelhas foram preenchidos com PRP autógeno à direita e deixados [...] vazios à esquerda. Avaliação macroscópica e histológica foram efetuadas 12 semanas mais tarde. Os resultados foram avaliados por um escore geral de ambas as avaliações macroscópica e histológica comparativamente entre os lados por meio do teste pareado de Wilcoxon. RESULTADOS: o aspecto macroscópico não foi uniforme entre os animais, nem diferiu entre os joelhos direitos e esquerdos (p=0,03125); em nenhum caso o tecido regenerado se nivelou com a cartilagem normal circundante. Ao exame histológico, cartilagem aparentemente normal não foi detectada em nenhum joelho, mas uma cartilagem pouco diferenciada estava presente em sete joelhos direitos e em três joelhos esquerdos. Tecido fibrocartilaginoso estava presente nos joelhos restantes, com diferença significante no escore geral entre os joelhos direitos e esquerdos (p=0,0313). CONCLUSÃO: o PRP como usado neste estudo tem propriedades reparativas da cartilagem articular no joelho de ovelhas, principalmente por estimular a formação de tecido fibrocartilaginoso. Trabalho Experimental. Abstract in english OBJECTIVE: to assess the regeneration of osteochondral defects in the joint cartilage of the knee induced by autologous platelet-rich plasma (pRp). METHODS: osteochondral defects produced in the trochlear groove of both knees of ten sheep; defects of the right knees were filled with autologous pRp a [...] nd the left knees were left unfilled. macroscopic and microscopic evaluation was carried out 12 week later. the results were evaluated by the total score of both macroscopic and microscopic evaluations comparing the two sides through the wilcoxon paired test. RESULTS: macroscopic appearance was not uniform among animals, nor was it different between the right and left knees (p=0.3125), and in no case the regenerated tissue was equal to the normal surrounding cartilage. at histological examination, apparently normal cartilage was not detected in any knee, but a poorly differentiated cartilage was present in 7 right knees, compared to 3 left knees. fibrocartilaginous tissue was present in most of the remaining knees, with a significant difference in the overall score between right and left knees (p=0.0313). CONCLUSION: the pRp as used in this study has reparative properties of the joint cartilage of sheep knees, mostly by stimulating the formation of a fibrocartilaginous tissue. Laboratory Investigation.

Márcio de Oliveira, Carneiro; Cláudio Henrique, Barbieri; José, Barbieri Neto.

2013-04-01

286

Estimation of focal and extra-focal radiation profiles based on Gaussian modeling in medical linear accelerators.  

Science.gov (United States)

The X-ray source or focal radiation is one of the factors that can degrade the conformal field edge in stereotactic body radiotherapy. For that reason, it is very important to estimate the total focal radiation profiles of linear accelerators, which consists of X-ray focal-spot radiation and extra-focal radiation profiles. Our purpose in this study was to propose an experimental method for estimating the focal-spot and extra-focal radiation profiles of linear accelerators based on triple Gaussian functions. We measured the total X-ray focal radiation profiles of the accelerators by moving a slit in conjunction with a photon field p-type silicon diode. The slit width was changed so that the extra-focal radiation could be optimally included in the total focal radiation. The total focal radiation profiles of an accelerator at 4-MV and 10-MV energies were approximated with a combination of triple Gaussian functions, which correspond to the focal-spot radiation, extra-focal radiation, and radiation transmitted through the slit assembly. As a result, the ratios of the Gaussian peak value of the extra-focal radiation to that of the focal spot for 4 and 10 MV were 0.077 and 0.159, respectively. The peak widths of the focal-spot and extra-focal radiation profiles were 0.57 and 25.0 mm for 4 MV, respectively, and 0.60 and 22.0 mm for 10 MV, respectively. We concluded that the proposed focal radiation profile model based on the triple Gaussian functions may be feasible for estimating the X-ray focal-spot and extra-focal radiation profiles. PMID:21431890

Anai, Shigeo; Arimura, Hidetaka; Nakamura, Katsumasa; Araki, Fujio; Matsuki, Takaomi; Yoshikawa, Hideki; Yoshidome, Satoshi; Shioyama, Yoshiyuki; Honda, Hiroshi; Ikeda, Nobuo

2011-07-01

287

A computer-assisted microscopic analysis of bone tissue developed inside a polyactive polymer implanted into an equine articular surface.  

Science.gov (United States)

One of the most promising applications for the restoration of small or moderately sized focal articular lesions is mosaicplasty (MP). Although recurrent hemarthrosis is a rare complication after MP, recently, various strategies have been designed to find an effective filling material to prevent postoperative bleeding from the donor site. The porous biodegradable polymer Polyactive (PA; a polyethylene glycol terephthalate - polybutylene terephthalate copolymer) represents a promising solution in this respect. A histological evaluation of the longterm PA-filled donor sites obtained from 10 experimental horses was performed. In this study, attention was primarily focused on the bone tissue developed in the plug. A computer-assisted image analysis and quantitative polarized light microscopic measurements of decalcified, longitudinally sectioned, dimethylmethylene blue (DMMB)- and picrosirius red (PS) stained sections revealed that the coverage area of the bone trabecules in the PA-filled donor tunnels was substantially (25%) enlarged compared to the neighboring cancellous bone. For this quantification, identical ROIs (regions of interest) were used and compared. The birefringence retardation values were also measured with a polarized light microscope using monochromatic light. Identical retardation values could be recorded from the bone trabeculae developed in the PA and in the neighboring bone, which indicates that the collagen orientation pattern does not differ significantly among these bone trabecules. Based on our new data, we speculate that PA promotes bone formation, and some of the currently identified degradation products of PA may enhance osteo-conduction and osteoinduction inside the donor canal. PMID:22806907

Albert, Réka; Vásárhelyi, Gábor; Bodó, Gábor; Kenyeres, Annamária; Wolf, Ervin; Papp, Tamás; Terdik, Tünde; Módis, László; Felszeghy, Szabolcs

2012-09-01

288

T2 star relaxation times for assessment of articular cartilage at 3 T: a feasibility study  

International Nuclear Information System (INIS)

T2 mapping techniques use the relaxation constant as an indirect marker of cartilage structure, and the relaxation constant has also been shown to be a sensitive parameter for cartilage evaluation. As a possible additional robust biomarker, T2* relaxation time is a potential, clinically feasible parameter for the biochemical evaluation of articular cartilage. The knees of 15 healthy volunteers and 15 patients after microfracture therapy (MFX) were evaluated with a multi-echo spin-echo T2 mapping technique and a multi-echo gradient-echo T2* mapping sequence at 3.0 Tesla MRI. Inline maps, using a log-linear least squares fitting method, were assessed with respect to the zonal dependency of T2 and T2* relaxation for the deep and superficial regions of healthy articular cartilage and cartilage repair tissue. There was a statistically significant correlation between T2 and T2* values. Both parameters demonstrated similar spatial dependency, with longer values measured toward the articular surface for healthy articular cartilage. No spatial variation was observed for cartilage repair tissue after MFX. Within this feasibility study, both T2 and T2* relaxation parameters demonstrated a similar response in the assessment of articular cartilage and cartilage repair tissue. The potential advantages of T2*-mapping of cartilage include faster imaging times and the opportunity for 3D acquisitions, thereby providing greater spatial resolution and complete coverage of the articular sn and complete coverage of the articular surface. (orig.)

289

Optical interconnections to focal plane arrays  

Energy Technology Data Exchange (ETDEWEB)

The authors have successfully demonstrated an optical data interconnection from the output of a focal plane array to the downstream data acquisition electronics. The demonstrated approach included a continuous wave laser beam directed at a multiple quantum well reflectance modulator connected to the focal plane array analog output. The output waveform from the optical interconnect was observed on an oscilloscope to be a replica of the input signal. They fed the output of the optical data link to the same data acquisition system used to characterize focal plane array performance. Measurements of the signal to noise ratio at the input and output of the optical interconnection showed that the signal to noise ratio was reduced by a factor of 10 or more. Analysis of the noise and link gain showed that the primary contributors to the additional noise were laser intensity noise and photodetector receiver noise. Subsequent efforts should be able to reduce these noise sources considerably and should result in substantially improved signal to noise performance. They also observed significant photocurrent generation in the reflectance modulator that imposes a current load on the focal plane array output amplifier. This current loading is an issue with the demonstrated approach because it tends to negate the power saving feature of the reflectance modulator interconnection concept.

Rienstra, J.L.; Hinckley, M.K.

2000-11-01

290

Towards Dualband Megapixel QWIP Focal Plane Arrays  

Science.gov (United States)

Mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) 1024 x 1024 pixel quantum well infrared photodetector (QWIP) focal planes have been demonstrated with excellent imaging performance. The MWIR QWIP detector array has demonstrated a noise equivalent differential temperature (NEDT) of 17 mK at a 95 K operating temperature with f/2.5 optics at 300 K background and the LWIR detector array has demonstrated a NEDT of 13 mK at a 70 K operating temperature with the same optical and background conditions as the MWIR detector array after the subtraction of system noise. Both MWIR and LWIR focal planes have shown background limited performance (BLIP) at 90 K and 70 K operating temperatures respectively, with similar optical and background conditions. In addition, we have demonstrated MWIR and LWIR pixel co-registered simultaneously readable dualband QWIP focal plane arrays. In this paper, we will discuss the performance in terms of quantum efficiency, NEDT, uniformity, operability, and modulation transfer functions of the 1024 x 1024 pixel arrays and the progress of dualband QWIP focal plane array development work.

Gunapala, S. D.; Bandara, S. V.; Liu, J. K.; Mumolo, J. M.; Hill, C. J.; Rafol, S. B.; Salazar, D.; Woolaway, J.; LeVan, P. D.; Tidrow, M. Z.

2006-01-01

291

Dual band QWIP focal plane array  

Science.gov (United States)

A quantum well infrared photodetector (QWIP) that provides two-color image sensing. Two different quantum wells are configured to absorb two different wavelengths. The QWIPs are arrayed in a focal plane array (FPA). The two-color QWIPs are selected for readout by selective electrical contact with the two different QWIPs or by the use of two different wavelength sensitive gratings.

Gunapala, Sarath D. (Inventor); Choi, Kwong Kit (Inventor); Bandara, Sumith V. (Inventor)

2005-01-01

292

Focal myasthenia gravis in a dog.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A 10-month-old American cocker spaniel was evaluated for megaesophagus, aspiration pneumonia, but no appendicular muscle weakness. During hospitalization, weakness of the facial muscles developed, this resolved with anticholinesterase administration. Serum antibodies against acetylcholine receptors were documented, confirming the diagnosis of focal myasthenia gravis. Diagnosis, management, and medical treatment are discussed.

Webb, A. A.; Taylor, S. M.; Mcphee, L.

1997-01-01

293

[Subtle focal diffusion abnormality in the hippocampus].  

Science.gov (United States)

A 53-year-old female patient presented with sudden onset confusion and disorientation. Further neurological examination was unremarkable and the patient showed a complete recovery after several hours. A magnetic resonance imaging (MRI) examination performed 2 days later revealed a tiny focal lesion in the lateral hippocampus in the diffusion weighted images consistent with transient global amnesia. PMID:22710991

Macht, S; Hellen, F; Wenzel, D; Turowski, B

2012-07-01

294

The effect of low-level Nd:YAG laser energy on adult articular cartilage in vitro.  

Science.gov (United States)

Reports of laser energy applied to soft tissues in vitro and in vivo suggest both stimulation and inhibition of specific metabolic processes, depending on the type of laser, the energy density (ED) used, the mode of delivery, and type of tissue studied. An earlier in vitro study of Nd:YAG laser irradiation of articular cartilage indicated stimulation of both matrix and DNA synthesis for 6 days following laser exposure. In vivo reports on the ability of Nd:YAG laser energy to stimulate the healing of partial-thickness cartilage defects are conflicting. In the present study, a noncontact continuous-wave Nd:YAG laser beam of varying EDs was applied to full-thickness adult articular cartilage explants maintained in organ culture; the metabolic processes of chondrocyte DNA synthesis and matrix synthesis were followed over 2 weeks. For both canine and bovine cartilage, low-levels of laser energy (ED 51-127 J/cm2) stimulated matrix synthesis at 6-7 days following laser exposure, with a concomitant decrease in baseline DNA synthesis. By 12-14 days, however, these dose-dependent effects were no longer seen, with no significant differences from control noted for any of the laser energies studied. Histologic analysis of the cartilage explants following laser exposure showed no significant differences in cell number or morphology between sample and control groups; however, a decrease in matrix proteoglycan staining was seen in the highest laser energy group at all time points. These findings indicate that exposure to low-level noncontact Nd:YAG laser energy promotes a significant stimulation of cartilage matrix synthesis. However, a single exposure may not be sufficient to promote a sustained upregulation of cartilage metabolism.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1550649

Spivak, J M; Grande, D A; Ben-Yishay, A; Menche, D S; Pitman, M I

1992-01-01

295

MR imaging of post-traumatic articular cartilage injuries confined to the femoral trochlea Arthroscopic correlation and clinical significance  

Energy Technology Data Exchange (ETDEWEB)

Objective: To assess and describe post-traumatic articular cartilage injuries isolated to the trochlear groove and provide insight into potential mechanism of injury. Materials and methods: We retrospectively evaluated MR imaging findings of all knee MRIs performed at our institution over the last 2 years (2450). Thirty patients met the criteria of a cartilage injury confined to the trochlear groove. In 15 cases, which were included in our study, arthroscopic correlation was available. Each plane was evaluated and graded for the presence and appearance of articular cartilage defects using a standard arthroscopic grading scheme adapted to MR imaging. Any additional pathological derangement was documented and information about the mechanism of injury was retrieved by chart review. Results: In all cases the cartilaginous injury was well demonstrated on MRI. In 13 patients additional pathological findings could be observed. The most frequently associated injury was a meniscal tear in nine patients. In eight cases, the arthroscopic grading of the trochlear injury matched exactly with the MRI findings. In the remaining seven cases, the discrepancy between MRI and arthroscopy was never higher than one grade. In 13 out of 15 of patients trauma mechanism could be evaluated. Twelve patients suffered an indirect twisting injury and one suffered a direct trauma to their knee. Conclusion: The findings of this study demonstrate that MR imaging allows reliable grading of isolated injury to the trochlear groove cartilage and assists in directing surgical diagnosis and treatment. These injuries may be the only hyaline cartilage injury in the knee and meniscal tears are a frequently associated finding. Therefore, it is important to search specifically for cartilage injuries of the trochlear groove in patients with anterior knee pain, even if other coexistent pathology could potentially explain the patient's symptoms.

Huegli, Rolf W. E-mail: rhuegli@uhbs.ch; Moelleken, Sonja M.C.; Stork, Alexander; Bonel, Harald M.; Bredella, Miriam A.; Meckel, Stephan; Genant, Harry K.; Tirman, Phillip F.J

2005-01-01

296

MR imaging of post-traumatic articular cartilage injuries confined to the femoral trochlea Arthroscopic correlation and clinical significance  

International Nuclear Information System (INIS)

Objective: To assess and describe post-traumatic articular cartilage injuries isolated to the trochlear groove and provide insight into potential mechanism of injury. Materials and methods: We retrospectively evaluated MR imaging findings of all knee MRIs performed at our institution over the last 2 years (2450). Thirty patients met the criteria of a cartilage injury confined to the trochlear groove. In 15 cases, which were included in our study, arthroscopic correlation was available. Each plane was evaluated and graded for the presence and appearance of articular cartilage defects using a standard arthroscopic grading scheme adapted to MR imaging. Any additional pathological derangement was documented and information about the mechanism of injury was retrieved by chart review. Results: In all cases the cartilaginous injury was well demonstrated on MRI. In 13 patients additional pathological findings could be observed. The most frequently associated injury was a meniscal tear in nine patients. In eight cases, the arthroscopic grading of the trochlear injury matched exactly with the MRI findings. In the remaining seven cases, the discrepancy between MRI and arthroscopy was never higher than one grade. In 13 out of 15 of patients trauma mechanism could be evaluated. Twelve patients suffered an indirect twisting injury and one suffered a direct trauma to their knee. Conclusion: The findings of this study demonstrate that MR imaging allows reliable grading of isolated ining allows reliable grading of isolated injury to the trochlear groove cartilage and assists in directing surgical diagnosis and treatment. These injuries may be the only hyaline cartilage injury in the knee and meniscal tears are a frequently associated finding. Therefore, it is important to search specifically for cartilage injuries of the trochlear groove in patients with anterior knee pain, even if other coexistent pathology could potentially explain the patient's symptoms

297

Three-dimensional CT imaging for the intra-articular fracture of distal radius  

International Nuclear Information System (INIS)

Three-dimensional CT imaging for the fracture of distal radius was performed in 47 patients including 12 with the intra-articular fracture of distal radius. These images were compared with those of plain radiographs and computed tomography. Three-dimensional CT was helpful in detecting the displacement of the fracture and in determining the location and the direction of the fragment. By elimination technique, detailed information could be obtained and the eliminated axial views of intra-articular fracture revealed the details of damage of the joint surface. It was helpful to classify the intra-articular fracture of distal radius. (author)

298

[Gait analysis after intra-articular calcaneus fractures].  

Science.gov (United States)

We retrospectively compared 20 patients with displaced intra-articular calcaneal fractures by clinical assessment and dynamic pedography. Eleven were treated operatively, 9 conservatively. The purpose was to identify differences in post-traumatic gait performance and to correlate the pedographic data to a clinical score to show its reliability. Twenty individuals without a history of foot injuries were used as a control group. Both groups had restricted motion in the subtalar joint, increased hindfoot and midfoot loading and decreased forefoot loading. Furthermore, they showed prolonged contact phases and an impaired ability to speed up gait during the toe-off phase. Load transfer from the hindfoot to the forefoot showed typical distribution patterns. The operatively treated group showed better functional results with fewer subjective complaints. PMID:8850080

Siegmeth, A; Petje, G; Mittlmeier, T; Vécsei, V

1996-01-01

299

Phenotypic modulation of human articular chondrocytes by bistratene A  

Directory of Open Access Journals (Sweden)

Full Text Available Chondrocytes undergo phenotypic alterations following extended periods in monolayer culture, i.e., they become bipolar and flattened, proliferate, and synthesise type I as opposed to type II collagen. This process has been termed chondrocyte dedifferentiation. Bistratene A is a macrolide polyether that specifically activates the delta isoform of protein kinase C (PKCdelta in some cell types. Here, we show that dedifferentiated human articular chondrocytes became rounded and underwent cell growth arrest after treatment with bistratene A. In addition, bistratene A-treated chondrocytes became more immunopositive for type II collagen, but less immunopositive for type I collagen. These phenotypic changes were associated with a prior and extensive disruption of actin microfilaments and translocation of PKCdelta to the nuclear membrane. Concurrent treatments of chondrocytes with a specific inhibitor of PKCdelta, rottlerin, partially blocked the morphological effects of bistratene A

Gargiulo B. J.

2002-06-01

300

RNA extraction from human articular cartilage by chondrocyte isolation.  

Science.gov (United States)

We report an optimized method for RNA extraction from human articular cartilage that does not require the use of specialized equipment or column purification. To maximize RNA yield while minimizing degradation and contamination, chondrocytes are isolated from the extracellular matrix and the traditional TRIzol protocol is modified to include two RNA-DNA-protein phase separations. We compared RNA extracted using this modified method with the traditional TRIzol method by spectrophotometry, Bioanalyzer, and real-time polymerase chain reaction (PCR). With the modified method, RNA recovery is increased by nearly 1?g per 100mg of cartilage, and RNA integrity number (RIN) is improved from 2.0 to 7.5. PMID:22776092

Ali, Shabana Amanda; Alman, Benjamin

2012-10-01

 
 
 
 
301

Instrumental neutron activation analysis of immature articular cartilage  

International Nuclear Information System (INIS)

In general, neutron activation analysis has characteristics that make it a favourable technique for the analysis of multi-elements and, as such, has frequently been applied to trace determinations in different materials. After activation with the whole reactor spectrum of neutrons, macro-activities of sodium-24 and chlorine-38 are produced in many biological materials and especially articular cartilage. These interfere with the gammma activities of determined elements or increase their detection limits. In this study, the possibility of exploiting the lower resonance integrals of these interfering elements relative to the important trace elements with epithermal neutrons was investigated. The use of thermal neutron filters, to enchance the selectivity of the analysis in cartilage matrix, was studied

302

Anticuerpo anticitrulina y manifestaciones extra articulares en artritis reumatoidea Anticitrulin antibody and the extra-articular manifestations in rheumatoid arthritis  

Directory of Open Access Journals (Sweden)

Full Text Available Los pacientes con artritis reumatidea (AR pueden desarrollar manifestaciones extra articulares (MExA, relacionadas a su morbi-mortalidad. Los anticuerpos anti-péptidos citrulinados cíclicos (ACCP son específicos para la AR y estan relacionados con el daño articular; y podrían tener rol patogénico en las MExA. Nuestro objetivo fue determinar la relación entre los anticuerpos ACCP y MExA en pacientes con AR. Se incluyeron 74 pacientes con diagnóstico de AR (ACR 1987 mayores de 18 años, de más de 6 meses de evolución, con MExA, y un control apareado por sexo y edad sin MExA por cada paciente. Las variables demográficas, clínicas y de laboratorio se compararon con test t, chi cuadrado o Mann-Whitney. Se realizó análisis multivariado; p ? 0.05. Los pacientes con MExA presentaron mayor título de anticuerpo ACCP (116 vs. 34, p A large proportion of rheumatoid arthritis (RA patients develop extra-articular manifestations (EAM, which are associated with morbidity and early mortality. Anti cyclic citrullinated peptide (ACCP antibody has proven to be highly specific for the diagnosis of RA, associated with severe joint damage and may have some role in the pathogenesis of EAM. The aim of this study was to determine the relationship between ACCP antibody and the presence of EAM in RA patients. Seventy four RA patients (ACR 1987 with EAM, > 18 years, more than 6 months duration were included, and an EAM free control, matched by sex and age, for each patient. Demographic, clinical and laboratory variables were compared using t-test, chi-square or Mann-Whitney test. Multivariate analysis was performed: p ? 0.05. Patients with EAM presented a greater value of ACCP antibody (116 vs. 34, p < 0.01 and rheumatoid factor (108 vs. 34.5, p < 0.01. Independent association with current smoking habit (p = 0.02, OR = 3.78, 95%: 1.17-12.2, RF positive (p = 0.04, OR 3.23, CI 95%: 1.04 to 11.8 and ACCP antibody positive (p = 0.04, OR 3.23, 95% CI: 1.04-10 was found. The patients with xerostomia (109 vs. 34, p = 0.04, xerophthalmia (150 vs. 34, p < 0.01, subcutaneous nodules (141 vs. 34, p < 0.01 and pulmonary fibrosis (158 vs. 34, p = 0.04 had a higher degree of the ACCP antibody, than controls. In conclusion, ACCP antibody positive, RF positive and smoking were independent risk factors for the development of MEXA.

María Jezabel Haye Salinas

2013-02-01

303

Radioulnar fusion for forearm defects in children - a salvage procedure  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english Eight children aged 1-14 yrs with defects in the forearm were treated with the one-bone forearm procedure and followed up for 1-11 yrs. The defects were due to pyogenic osteomyelitis (n=3), osteochondroma (n=3), neurofibromatosis (n=1) and ulnar dysmelia (n=1). The radius was fixed to the ulna shaft [...] with an intramedullary pin in six cases, and two children had centralisation of the radial metaphysis onto the ulna for "radial club hand" type deformity with Kirschner wires. All forearms united in 3-6 months. Shortening ranged from 1-10 cm. Fixed flexion deformity of the elbow (20°) resulted in one child and cubitus valgus (20°) occurred in another. One child had a radial articular tilt of 45°. The procedure achieved stability at the wrist and elbow. There was cosmetic and functional improvement in all patients.

MN, Rasool.

2008-03-01

304

X-ray sources of medical linear accelerators: focal and extra-focal radiation.  

Science.gov (United States)

A computerized tomography (CT) reconstruction technique has been used to make quantitative measurements of the size and shape of the focal spot in medical linear accelerators. Using this technique, we have measured the focal spots in a total of nine accelerators, including (i) two Varian Clinac 2100c's, (ii) two Atomic Energy of Canada Ltd. (AECL) Therac-25's, (iii) two AECL Therac 6's, (iv) a Siemens KD-2, (v) a Varian Clinac 600c (4 MV), and (vi) an AECL Therac-20. Some of these focal spots were monitored for changes over a 2-yr period. It has been found that (i) the size and shape of the source spot varies greatly between accelerators of different design ranging from 0.5 to 3.4 mm in full width at half maximum (FWHM); and (ii) for accelerators of the same design, the focal spots are very similar. In addition to the measurements of the focal spot, a new technique for measuring the magnitude and distribution of extra-focal radiation originating from the linear accelerator head (flattening filter, primary collimator) has also been developed. The extra-focal radiation produced by a Varian Clinac 2100c accelerator was measured using this technique and it was found that the extra-focal radiation accounts for as much as 8% of the total photon fluence reaching the isocenter. The majority (75%) of this extra-focal radiation originates from within a circle 6 cm in diameter at the target plane. The source MTFs for each of the measured focal spots have been calculated in order to assess their influence on the spatial resolution of verification images. The limiting spatial resolution (i.e., 10% modulation) for all the source MTFs is 1.8 mm-1 or greater when used for transmission radiography at a magnification of 1.2. The extra-focal radiation, which produces a low-frequency drop in the source MTFs of up to 8%, changes with field size. As a result, the source MTFs of linear accelerators depend not only on the design of individual accelerators and image magnification, but also on the field size used when forming an image. PMID:8289724

Jaffray, D A; Battista, J J; Fenster, A; Munro, P

1993-01-01

305

Defect in Phosphorene  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Defects are inevitably present in materials and always can affect their properties. Here, first-principles calculations are performed to study the stability, structural and electronic properties of typical point defects in semiconducting phosphorene, including the Stone-Wales (SW) defect, single and double vacancy (SV5566, DV585, DV555777 and DV4104) defects. We find that these defects are all much easily created in phosphorene with higher areal density compared with graphen...

Hu, Wei; Yang, Jinlong

2014-01-01

306

On Holographic Defect Entropy  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We study a number of (3 + 1)- and (2 + 1)-dimensional defect and boundary conformal field theories holographically dual to supergravity theories. In all cases the defects or boundaries are planar, and the defects are codimension-one. Using holography, we compute the entanglement entropy of a (hemi-)spherical region centered on the defect (boundary). We define defect and boundary entropies from the entanglement entropy by an appropriate background subtraction. For some (3 + 1)-dimensional theo...

John Estesblackett Laboratory, Imperial College; Kristan Jensen(Department of Physics and Astronomy, University of Victoria, Victoria, BC V8W 3P6, Canada); Andy O’Bannon(Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, U.K.); Efstratios Tsatis(8 Kotylaiou Street, Athens 11364, Greece); Timm Wrase(Stanford Institute for Theoretical Physics, Stanford University, Stanford, CA 94305, U.S.A.)

2014-01-01

307

New focal plane detector system for HIRA at NSC  

International Nuclear Information System (INIS)

A new focal plane detector system has been developed and installed at focal plane of the recoil mass spectrometer. It consists of a parallel grid avalanche counter (PGAC) followed by a detector telescope

308

Focal Nodular Hyperplasia in children presenting as acute Cholecystitis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this case report, a female child of 10 years old presented with pain epigastrium and with sonographic features of acute cholecystitis. Later on, the focal mass in the liver was diagnosed by Magnetic Resonance Imaging (MRI) examination and proved by the biopsy as focal nodular hyperplasia (FNH), a benign focal response of the liver and a hepatic mass. Although focal nodular hyperplasia is rare mass in children however, Computed Tomography (CT) scan / Magnetic Resonance Imaging (MRI) examina...

Al Shehri, Fahad

2010-01-01

309

Hemorrhagc focal nodular hyperplasia in young men: A case report  

International Nuclear Information System (INIS)

In general, focal nodular hyperplasia is a hepatic lesion that most frequently affects the healthy women of reproductive age. Focal nodular hyperplasia lesions have a benign natural course; the majority of the cases remain asymptomatic and complications are rare. Spontaneous hemorrhage of focal nodular hyperplasia is a rare disease, and the hemorrhage in young men is even more uncommon. We report a rare case of spontaneous hemorrhage of focal nodular hyperplasia in a 19-year-old man.

310

Extra-articular disease manifestations in rheumatoid arthritis: incidence trends and risk factors over 46 years  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Objective: To investigate the trends in incidence of extra-articular rheumatoid arthritis (ExRA) in a well defined community based cohort of patients with rheumatoid arthritis (RA), and to examine possible predictors of ExRA occurrence.

Turesson, C.; O Fallon, W.; Crowson, C.; Gabriel, S.; Matteson, E.

2003-01-01

311

Displaced intra-articular glenoid fractures treated by open reduction and internal fixation.  

Science.gov (United States)

Displaced intra-articular glenoid fractures are extremely rare. Anatomic reduction, rigid internal fixation and early mobilization restored a full, painless range of motion in our two cases. PMID:3795314

Aulicino, P L; Reinert, C; Kornberg, M; Williamson, S

1986-12-01

312

The evolution of articular cartilage imaging and its impact on clinical practice  

International Nuclear Information System (INIS)

Over the past four decades, articular cartilage imaging has developed rapidly. Imaging now plays a critical role not only in clinical practice and therapeutic decisions but also in the basic research probing our understanding of cartilage physiology and biomechanics. (orig.)

313

Prevalência de hipermobilidade articular em crianças pré-escolares / Prevalence of joint hypermobility in preschool children / Prevalencia de hipermovilidad articular en niños pre-escolares  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A hipermobilidade articular é a capacidade de realizar movimentos em amplitudes maiores que a normal. O presente estudo teve como objetivo estabelecer a prevalência de hipermobilidade articular em crianças pré-escolares da Rede Municipal de Educação de Londrina/PR. O estudo foi do tipo transversal c [...] om amostra constituída de 366 crianças, de 5 e 6 anos de idade. Verificou-se que, das crianças pré-escolares avaliadas, 198 (54,1%) apresentaram hipermobilidade articular, sendo 96 (59,6%) do sexo feminino e 102 (49,8%) do masculino. A hipermobilidade articular foi encontrada com maior frequência nas articulações de cotovelo e joelho, onde ocorreu a hiperextensão. Não houve diferença estatisticamente significante entre os grupos masculino e feminino em relação à hipermobilidade articular (?²=3,539, p=0,072). Pode-se concluir que a hipermobilidade articular nas crianças pré-escolares foi achado comum, compatível com a faixa etária da população avaliada no estudo. Abstract in spanish La hipermovilidad articular es la capacidad de realizar movimientos en amplitudes mayores que lo normal. El presente estudio tuvo como objetivo establecer la prevalencia de hipermovilidad articular en niños pre-escolares de la Red Municipal de Educación de Londrina/PR. El estudio fue de tipo transve [...] rsal con una muestra constituida de 366 niños, de 5 a 6 años de edad. Se verificó que los niños pre-escolares evaluados, 198 (54,1%) presentaron hipermovilidad articular, siendo 96 (59,6%) de sexo femenino y 102 (49,8%) de sexo masculino. La hipermovilidad articular fue encontrada con mayor frecuencia en las articulaciones del tobillo y rodilla, donde ocurre la hiperextensión. No hubo diferencia estadísticamente significativa entre los grupos masculino y femenino en relación a la hipermovilidad articular (?²=3,539, p=0,072). Se puede concluir que la hipermovilidad articular en los niños pre-escolares fue encontrada normal, compatible con la línea etaria de la población evaluada en el estudio. Abstract in english Joint hypermobility is the ability to perform movements with a range of motion that is wider than normal. This study aimed at establishing the prevalence of joint hypermobility in junior kindergarten and senior kindergarten children from the Municipal Education System of Londrina, Paraná, Brasil. Th [...] e study was cross-­sectional, with a sample of 366 children aged between 5 and 6 years. The detection of joint hypermobility was based on the criteria proposed in literature. It was found that 198 (54.1%) of the children evaluated had joint hypermobility, 96 (59.6%) were girls and 102 (49.8%) were boys. Joint hypermobility was found more frequently in the elbow and knee joints, where hyperextension occurred. There was no statistically significant difference between the male and female groups in relation to joint hypermobility (?²=3.539, p=0.072). We can conclude that joint hypermobility found in the junior kindergarten and senior kindergarten children evaluated was common and compatible with the age of the population evaluated in this study.

Jessica Caroliny de Jesus, Neves; Fabíola Unbehaun, Cibinello; Leonardo George Vitorio, Vitor; Débora, Beckner; Claudia Patrícia Cardoso Martins, Siqueira; Dirce Shizuko, Fujisawa.

2013-06-01

314

Radiopneumographic characteristics of focal pneumonia in children  

International Nuclear Information System (INIS)

Zonal ventilation and blood flow were studied by the radiopneumography method in 50 children of school age with lower-lobe-of-the lung focal pneumonia (26 with left-side and 24 with right-side). It is established that during right-side localization of pneumonic focus preserved was the predomination of ventilation of right lung relative to left. Complete normalization of common and regional indexes of ventilation and blood flow was established by the 21st day from the beginning of treatment during right-side focal pneumonias. In case of left-side localization of pneumonic focus only partial reduction of external respiration and perfusion comes. Therefore, compensatory and reducing capabilities of right lung are preferrable

315

Likelihood analysis of earthquake focal mechanism distributions  

CERN Document Server

In our paper published earlier we discussed forecasts of earthquake focal mechanism and ways to test the forecast efficiency. Several verification methods were proposed, but they were based on ad-hoc, empirical assumptions, thus their performance is questionable. In this work we apply a conventional likelihood method to measure a skill of forecast. The advantage of such an approach is that earthquake rate prediction can in principle be adequately combined with focal mechanism forecast, if both are based on the likelihood scores, resulting in a general forecast optimization. To calculate the likelihood score we need to compare actual forecasts or occurrences of predicted events with the null hypothesis that the mechanism's 3-D orientation is random. For double-couple source orientation the random probability distribution function is not uniform, which complicates the calculation of the likelihood value. To better understand the resulting complexities we calculate the information (likelihood) score for two rota...

Kagan, Y Y

2014-01-01

316

Chest pain in focal musculoskeletal disorders.  

Science.gov (United States)

The musculoskeletal system is a recognized source of chest pain. However, despite the apparently benign origin, patients with musculoskeletal chest pain remain under-diagnosed, untreated, and potentially continuously disabled in terms of anxiety, depression, and activities of daily living. Several overlapping conditions and syndromes of focal disorders, including Tietze syndrome, costochondritis, chest wall syndrome, muscle tenderness, slipping rib, cervical angina, and segmental dysfunction of the cervical and thoracic spine, have been reported to cause pain. For most of these syndromes, evidence arises mainly from case stories and empiric knowledge. For segmental dysfunction, clinical features of musculoskeletal chest pain have been characterized in a few clinical trials. This article summarizes the most commonly encountered syndromes of focal musculoskeletal disorders in clinical practice. PMID:20380955

Stochkendahl, Mette Jensen; Christensen, Henrik Wulff

2010-03-01

317

Aerogel detector with a Fresnel lens focalization  

International Nuclear Information System (INIS)

The use of threshold Cherenkov detectors for the identification of high momentum particles in high energy physics experiments is connected with the efficiency of detection of light in the aerogel. As one goes lower in the refractive index, less photons are emitted, and more attention should be paid to the improvements of the detection efficiency. The light integration box method relies on photomultipliers of large size and requires even two of them. We have studied the possibility to use a thin focalizing element (Fresnel lens) between the aerogel and the photomultiplier to focalize the light onto a smaller diameter photomultiplier. The results show that for good aerogel and low indices of refraction (<1.01) the scheme with the aerogel and the Fresnel lens may be superior and less costly than the conventional set-up.

318

Infrared focal plane arrays for planetary missions  

Science.gov (United States)

Requirements for infrared detector array focal planes suitable for a set of prospective planetary missions are developed. Using the Galileo mission to Jupiter as a starting point, objectives and constraints applicable to outer planet missions are developed. The concept for an advanced mapping spectrometer utilizing 128 x 128 element infrared detector arrays is described. Specific implementations for the Saturn Orbiter Dual Probe mission, a Mars Orbiter mission, and a Titan Orbiter mission are defined. The analysis indicates that within the 1 to 5 micron range, broad scientific objectives for these missions can be met using focal plane arrays with detectivities on the order of 10 to the 14th cm sq root of Hz per W. The realization of such high detectivities in a low background application will necessitate careful development of the method by which the detector signals are multiplexed and read out.

Wellman, J. B.

1979-01-01

319

Human articular cartilage and fibrocartilage: a study with high-angle x-ray diffraction.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

High-angle x-ray diffraction was applied to the study of four meniscal fibrocartilages and 11 articular cartilages from patients suffering from various articular disorders. In eight samples microcrystals were seen, apatite most frequently, CaHPO4 in two instances, calcium pyrophosphate dihydrate (CPPD) in one. These results confirm the association of various crystals in a single joint, and favour their heterogenous partition on collagen fibres.

Albiser, G.; Netter, P.; Faure, G.; Horn, P.; Delagoutte, J. P.; Gaucher, A.

1984-01-01

320

Diagnosis and management of an intra-articular foreign body in the foot.  

LENUS (Irish Health Repository)

We describe a case of a small intra-articular foreign body in the foot presenting 48 hours following injury, which at operation showed early evidence of septic arthritis. It is essential to accurately localise periarticular foreign bodies in the foot and proceed to arthrotomy and debridement in all cases where there is radiological or clinical evidence to suggest intra-articular retention of a foreign body.

Mulhall, K J

2002-10-01

 
 
 
 
321

Chondrogenic potential of human articular chondrocytes and skeletal stem cells: A comparative study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Regenerative medicine strategies have increasingly focused on skeletal stem cells (SSCs), in response to concerns such as donor site morbidity, dedifferentiation and limited lifespan associated with the use of articular chondrocytes for cartilage repair. The suitability of SSCs for cartilage regeneration, however, remains to be fully determined. This study has examined the chondrogenic potential of human STRO-1-immunoselected SSCs (STRO-1+ SSCs), in comparison to human articular chondrocytes ...

Li, Siwei; Sengers, Bram G.; Oreffo, Richard Oc; Tare, Rahul S.

2015-01-01

322

Analgesic effects of intra-articular fentanyl, pethidine and dexamethasone after knee arthroscopic surgery  

Digital Repository Infrastructure Vision for European Research (DRIVER)

BACKGROUND: Many different methods have been used in an effort to provide adequate analgesia after knee arthroscopic surgery. In this study analgesic effect of intra-articular fentanyl, pethidine and dexamethasone was compared. METHODS: In a double blind randomized study 48 male patients undergoing knee arthroscopic meniscectomy were allocated to groups receiving intra-articular fentanyl 50 µg or pethidine 20 mg or dexamethasone 8 mg at the end of arthroscopy during general aesthesia. P...

Saryazd, H.; Kashefi, P.; Heydari, M.; Kiani, A.

2006-01-01

323

Vulnerability of the superficial zone of immature articular cartilage to compressive injury  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Objective The zonal composition and functioning of adult articular cartilage causes depth-dependent responses to compressive injury. In immature cartilage, shear and compressive moduli as well as collagen and sulfated glycosaminoglycan (sGAG) content also vary with depth. However, there is little understanding of the depth-dependent damage caused by injury. Since injury to immature knee joints most often causes articular cartilage lesions, this study was undertaken to characterize the zon...

Rolauffs, Bernd; Muehleman, Carol; Li, Jun; Kurz, Bodo; Kuettner, Klaus E.; Frank, Eliot; Grodzinsky, Alan J.

2010-01-01

324

The functional morphology of the superior articular processes of the lumbar vertebrae.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The bony trabeculae in the superior articular processes of the lumbar vertebrae form a series of overlapping pointed arches that correspond to the lines of stress produced during rotation. By using a photoelastic model, it has been possible to demonstrate that this structural arrangement is a functional adaptation to alternate lateral and medial bending movements. The functional significance of the articular processes is obviously to limit rotation, which can take place in the lumbar segment ...

Putz, R.

1985-01-01

325

Three-dimensional surface analysis of young adult human articular cartilage.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The objective of this investigation was to determine whether the surface of young adult human articular cartilage was smooth as defined by industrial standards for metal surfaces. Human articular cartilage with attached subchondral bone from the midregion of the trochlear surface of the talus was obtained postmortem from 7 donors (aged 29 +/- 9 y). The specimens were processed using multiple fixation techniques prior to scanning electron microscopy and 3-dimensional stereoscopic analysis. Thr...

Bloebaum, R. D.; Radley, K. M.

1995-01-01

326

Usefulness of fluoroscopy-guided intra-articular injection of the knee  

International Nuclear Information System (INIS)

To determine the accuracy of the intra-articular location of hyaluronic acid injection using a blind approach and to establish the usefulness of fluoroscopy-guided intra-articular injection. A fluoroscopy unit was used for 368 intra-articular injections of hyaluronic acid to 93 knees in 65 patients. Initially, blind needle positioning was conducted on the fluoroscopy table. The failure rate of the blind approach among the 368 injections was evaluated, and a relationship between the Kellgren-Lawrence grade (K-L grade) and the incidence of repeated failures using the blind approach was determined for injections to 52 knees in 37 patients who received a complete cycle of injections (five consecutive injections with a one-week interval between injections). Using a blind approach, 298 of 368 trials (81.2%) resulted in a needle tip being placed in an intra-articular location, while 70 of 368 trials resulted in an extra-articular placement of the needle tip. Among 52 knees to which a complete cycle of injection (five consecutive injections with a one-week interval between injections) was administered, repeated failure of intra-articular placement using the blind approach was seen for 18 knees (34.6%); a more severe K-L grade assigned was associated with a higher rate of repeated failure. However, the trend was not statistically significant based on the Chi-squared test (? value = 0.14). Fluoroscopy-guided needle placement may be helpful to ensure therapeutic intra-articularful to ensure therapeutic intra-articular injection of the knee

327

Efficacy of Intra-Articular Injection of Celecoxib in a Rabbit Model of Osteoarthritis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Introduction: Osteoarthritis is the most common form of arthritis. It is a slowly progressive joint disease typically seen in middle-age to elderly people. Intra-articular injection of hyaluronic acid is a well-documented treatment for knee osteoarthritis. Celebrex® (celecoxib) is a novel nonsteroidal anti-inflammatory drug, which could help to reduce inflammation and to reduce pain. The aim of this study was to evaluate the effects of intra-articular injection of celecoxib in a rabbit osteo...

Huilin Yang; Genlin Wang; Dinghua Jiang; Lixin Huang; Qin Shi; Xuesong Zhu; Jun Zou

2010-01-01

328

The role of intra-articular hyaluronan (Sinovial®) in the treatment of osteoarthritis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Osteoarthritis (OA) leads to significant pain and disability. For pain relief, a tailored approach using non-pharmacological and pharmacological therapies is recommended. If adequate symptom relief is not achieved with acetaminophen, other pharmacological options include non-steroidal anti-inflammatory drugs (NSAIDs), topical analgesics, intra-articular corticosteroids and intra-articular hyaluronic acid (HA) viscosupplementation. Most of these therapies generally do not i...

Gigante, Antonio; Callegari, Leonardo

2010-01-01

329

Paraspinal Abscess Communicated with Epidural Abscess after Extra-Articular Facet Joint Injection  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Facet joint injection is considered to be a safe procedure. There have been some reported cases of facet joint pyogenic infection and also 3 cases of facet joint infection spreading to paraspinal muscle and epidural space due to intra-articular injections. To the author's knowledge, paraspinal and epidural abscesses after facet joint injection without facet joint pyogenic infection have not been reported. Here we report a case in which extra-articular facet joint injection resulted in paraspi...

Park, Moon-soo; Moon, Seong-hwan; Hahn, Soo-bong; Lee, Hwan-mo

2007-01-01

330

In vivo studies of articular tissue damage mediated by catabolin/interleukin 1.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A partially purified porcine synovial catabolin interleukin 1 (CF) preparation was injected intra-articularly into rabbit stifle (knee) joints. Radiolabelled CF was rapidly cleared from the joint (0.4 h). Repeated injections of CF caused a marked loss of articular cartilage glycosaminoglycan (GAG) and a great increase in synovial fluid GAG. 35SO4 uptake was inhibited. Time course experiments after a single injection produced similar loss of GAG from knee cartilages, which was maximal three da...

Dingle, J. T.; Page Thomas, D. P.; King, B.; Bard, D. R.

1987-01-01

331

Intra-articular ganglion cysts of the knee: clinical and MR imaging features  

International Nuclear Information System (INIS)

The purpose of this study was to present clinical and MR imaging features of intra-articular ganglion cysts of the knee. Retrospective review of 1685 consecutive medical records and MR examinations of the knee performed at three imaging centers allowed identification of 20 patients (13 men and 7 women; mean age 35 years), in whom evidence of intra-articular ganglion cyst was seen. Of the 20 ganglion cysts, 5 were found in the infrapatellar fat pad, 10 arose from the posterior cruciate ligament, and 5 from the anterior cruciate ligament. Three of five patients with ganglion cyst in the infrapatellar fat pad had a palpable mass. In 7 of 15 patients with ganglion cyst in the intercondylar notch, exacerbation of pain occurred in a squatting position. On four MR arthrographies, ganglion cysts were an intra-articular round, lobulated, low signal intensity lesion. Five cases of fat-suppressed contrast-enhanced T1-weighted SE images demonstrated peripheral thin rim enhancement. The clinical presentation of intra-articular ganglion cyst is varied according to its intra-articular location. The MR appearance of intra-articular ganglion cyst is characteristic and usually associated with the cruciate ligament or the infrapatellar fat pad. Magnetic resonance arthrography has no definite advantage over conventional MR in the evaluation of the lesion. For intra-articular ganglion cyst in the infrapatellar fat pad, fat-suppressed contrast-enhanced MR imaging could be useful, because anced MR imaging could be useful, because a thin, rim-enhancing feature of intra-articular ganglion cyst allows it to be distinguished from synovial hemangioma and synovial sarcoma. (orig.)

332

Lead Induces an Osteoarthritis-like Phenotype in Articular Chondrocytes through Disruption of TGF-? Signaling  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Lead remains a significant environmental toxin, and we believe we may have identified a novel target of lead toxicity in articular chondrocytes. These cells are responsible for the maintenance of joint matrix, and do so under the regulation of TGF-? signaling. As lead is concentrated in articular cartilage, we hypothesize that it can disrupt normal chondrocyte phenotype through suppression of TGF-? signaling. These experiments examine the effects of lead exposure in vivo and in vitro at bio...

Holz, Jonathan D.; Beier, Eric; Sheu, Tzong-jen; Ubayawardena, Resika; Wang, Meina; Sampson, Erik R.; Rosier, Randy N.; Zuscik, Michael; Puzas, J. Edward

2012-01-01

333

The Temporal Response of the Friction Coefficient of Articular Cartilage Depends on the Contact Area  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The hypothesis of this study is that the time constant for the transient increase in friction coefficient of articular cartilage under a constant load is proportional to the size of the contact area, as predicated by the dependence of the frictional response on interstitial fluid pressurization. This hypothesis is verified experimentally from measurements of the frictional response of bovine articular cartilage disks of three different diameters (4, 6 and 8 mm) against glass. At two different...

Carter, Michael J.; Basalo, Ines M.; Ateshian, Gerard A.

2007-01-01

334

Reaction-Diffusion-Delay Model for EPO/TNF-$\\alpha$? Interaction in Articular Cartilage Lesion Abatement  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Injuries to articular cartilage result in the development of lesions that form on the surface of the cartilage. Such lesions are associated with articular cartilage degeneration and osteoarthritis. The typical injury response often causes collateral damage, primarily an effect of inflammation, which results in the spread of lesions beyond the region where the initial injury occurs. We present a minimal mathematical model based on known mechanisms to investigate the spread an...

Graham, Jason M.; Ayati, Bruce P.; Ding, Lei; Ramakrishnan, Prem S.; Martin, James A.

2011-01-01

335

Intra-articular ganglion cysts of the knee: clinical and MR imaging features  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study was to present clinical and MR imaging features of intra-articular ganglion cysts of the knee. Retrospective review of 1685 consecutive medical records and MR examinations of the knee performed at three imaging centers allowed identification of 20 patients (13 men and 7 women; mean age 35 years), in whom evidence of intra-articular ganglion cyst was seen. Of the 20 ganglion cysts, 5 were found in the infrapatellar fat pad, 10 arose from the posterior cruciate ligament, and 5 from the anterior cruciate ligament. Three of five patients with ganglion cyst in the infrapatellar fat pad had a palpable mass. In 7 of 15 patients with ganglion cyst in the intercondylar notch, exacerbation of pain occurred in a squatting position. On four MR arthrographies, ganglion cysts were an intra-articular round, lobulated, low signal intensity lesion. Five cases of fat-suppressed contrast-enhanced T1-weighted SE images demonstrated peripheral thin rim enhancement. The clinical presentation of intra-articular ganglion cyst is varied according to its intra-articular location. The MR appearance of intra-articular ganglion cyst is characteristic and usually associated with the cruciate ligament or the infrapatellar fat pad. Magnetic resonance arthrography has no definite advantage over conventional MR in the evaluation of the lesion. For intra-articular ganglion cyst in the infrapatellar fat pad, fat-suppressed contrast-enhanced MR imaging could be useful, because a thin, rim-enhancing feature of intra-articular ganglion cyst allows it to be distinguished from synovial hemangioma and synovial sarcoma. (orig.)

Kim, M.G.; Cho, W.H. [Dept. of Radiology, Sanggye Paik Hospital, Inje University, Seoul (Korea); Kim, B.H.; Choi, J.A.; Lee, N.J.; Chung, K.B. [Dept. of Diagnostic Radiology, College of Medicine, Korea University, Seoul (Korea); Choi, Y.S.; Cho, S.B. [Dept. of Radiology, School of Medicine, Eulji University, Seoul (Korea); Lim, H.C. [Dept. of Orthopedic Surgery, College of Medicine, Korea University, Seoul (Korea)

2001-05-01

336

Atypical Findings of Focal Nodular Hyperplasia with Gadoxetic Acid (Gd-EOB-DTPA)-Enhanced Magnetic Resonance Imaging  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We report two cases of focal nodular hyperplasia in patients following gadoxetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging confirmed with histopathology. These cases showed an atypical pattern during the delayed-hepatobiliary phase after the injection of gadoxetic acid. One case showed a total defect, and the other showed a peripheral ring-like enhancement without a visible central scar, mimicking hepatocellular carcinoma. The pathologic examination demonstrated that the two lesi...

Yoon, Jung-hee; Kim, Ji-yeon

2014-01-01

337

Defects in metals  

International Nuclear Information System (INIS)

The application of positron annihilation spectroscopy (PAS) to the study of defects in metals has led to increased knowledge on lattice-defect properties during the past decade in two areas: the determination of atomic defect properties, particularly those of monovacancies, and the monitoring and characterization of vacancy-like microstructure development during post-irradiation and post-quench annealing. The study of defects in metals by PAS is reviewed within the context of the other available techniques for defect studies. The strengths and weaknesses of PAS as a method for the characterization of defect microstructures are considered. The additional possibilities for using the positron as a localized probe of the atomic and electronic structures of atomic defects are discussed, based upon theoretical calculations of the annihilation characteristics of defect-trapped positrons and experimental observations. Finally, the present status and future potential of PAS as a tool for the study of defects in metals is considered. 71 references, 9 figures

338

Lavado articular por punción versus artroscopia en el tratamiento de la osteoartritis de rodilla / Articular lavage by puncture versus arthroscopy in the treatment of knee osteoarthritis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Se sabe que el lavado articular y el debridamiento son opciones en el tratamiento de la osteoartritis de rodilla. Se realizó un estudio prospectivo, abierto y aleatorizado que incluyó 100 pacientes con OA de rodilla (criterio ACR) en estadios II y III de Kellgren y Lawrence para evaluar la utilidad [...] y la eficacia del lavado articular por punción en comparación con el lavado y debridamiento artroscópico. Se distribuyeron en: grupo A (lavado por punción) y grupo B (lavado y debridamiento artroscópico). Se consideraron variables relacionadas con el dolor y la función articular que fueron analizadas al inicio del tratamiento y 90 d después; se realizó un análisis estadístico con el empleo del test de Chi cuadrado y el de t-Student, significación estadística p Abstract in english It is known that the articular lavage and débridement are options for the treatment of knee osteoarthritis. A prospective, open and randomized study that included 100 patients with knee osteoarthritis (criterion of the American College of Rheumatology) at stages II and III of Kellgren and Lawrence w [...] as conducted to evaluate the usefulness and efficiency of the articular lavage by puncture compared with lavage and arthroscopic débridement. They were distributed into: group A (lavage by puncture) and group B (lavage and arthroscopic débridement). Variables related to pain and articular function that were analyzed at the beginning of the treatment and 90 days later, were considered. A statistical analysis was made by using Chi square test and Student's t test with a statistical significance of p

Araceli, Chico Capote; Miguel, Hernán Estévez del Toro; Idalmis, Barbán Alba; Ángela, Gutiérrez Rojas; Juan Bautista, Kourí.

2004-08-01

339

Collapsing focal segmental glomerulosclerosis: Current concepts  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Collapsing focal segmental glomerulosclerosis (cFSGS), also known as collapsing glomerulopathy is currently classified under the rubric of FSGS. However, its defining morphological features are in stark contrast to those observed in most other variants of FSGS. During the early stage of the disease, the lesion is characterized pathologically by an implosive segmental and/or global collapse of the glomerular capillary tufts, marked hypertrophy and hyperplasia of podocytes, and severe tubuloint...

Mubarak, Muhammed

2012-01-01

340

Corneal damage following focal laser intervention  

International Nuclear Information System (INIS)

Corneal endothelial damage caused by two levels of laser energy was studied in albino rats. Observations indicate that focal, non-invasive destruction of the endothelium can be consistently generated by laser treatment following anterior chamber localization of fluorescein. The dose related effects of this described protocol will make it possible to study different aspects of posterior corneal function without generating invasive, inflammatory side effects. (author)

 
 
 
 
341

Multiwavelength infrared focal plane array detector  

Science.gov (United States)

A multiwavelength focal plane array infrared detector is included on a common substrate having formed on its top face a plurality of In.sub.x Ga.sub.1-x As (x.ltoreq.0.53) absorption layers, between each pair of which a plurality of InAs.sub.y P.sub.1-y (ycontacts being formed on a portion of each of the exposed areas, and on the bottom of the substrate for facilitating electrical connections thereto.

Forrest, Stephen R. (Inventor); Olsen, Gregory H. (Inventor); Kim, Dong-Su (Inventor); Lange, Michael J. (Inventor)

1995-01-01

342

Focal nodular hyperplasia: Long-Term prognosis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background: A large number of patients with focal nodular hyperplasia (FNH) were examined. We reviewed 430 cases and made 1012 measurements. Patients require special care to cope with their concerns and anxieties. Typically, these patients are very uncertain, even after they received extensive medical advice. Clearly, further possible growth and the thought that this may be a cancer, in spite of reassurances, is troubling. Further, specific data analysis of the different stages of FNH...

Theophil, Sophie

2010-01-01

343

Atypical presentation of focal nodular hyperplasia  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A 27-year-old man, previously healthy, had an enlarging liver mass incidentally noted at a health check-up 6 months earlier. There were no known risk factors for hepatocellular carcinoma. The hepatic tumour seen on magnetic resonance imaging had characteristics of high T2 and low T1 signals, early hyper-enhancement and mild delayed enhancement, which was atypical for focal nodular hyperplasia (FNH). An atypical hepatectomy was performed smoothly and the pathologic confirmation of FNH was fina...

Ho, Cheng-maw; Lee, Po-huang

2010-01-01

344

Targeting Focal Adhesion Kinase in Neuroblastoma  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Neuroblastoma is the most common extracranial solid tumor encountered in children, and continues to carry a dismal prognosis. Focal adhesion kinase (FAK) has been shown to be upregulated in a number of human tumors and is related to tumor virulence and patient prognosis. We have demonstrated FAK expression in human neuroblastoma cell lines and tumors, and have shown that FAK is important for neuroblastoma tumor cell viability. We have also demonstrated that FAK inhibition through a number of ...

Gillory, Lauren; Beierle, Elizabeth A.

2010-01-01

345

www.focal.ie terminology project  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents an EU-funded project for Irish and Welsh which will be accessible from 2007 at www.focal.ie. This is a major initiative in two Celtic languages. The context and content of the Irish implementation strand are discussed here. An overview is presented of the development of terminology in Irish, and the project presented demonstrates the potential for innovation and renewal through the development of sophisticated linguistic tools for users of all levels. This paper explores s...

Bhreathnach, U?na; Nic Phaidin, Caoilfhionn; Ui Bhraonain, Donla

2006-01-01

346

Crowding in the GAIA spectrograph focal plane  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Superpositions of stellar tracings are present in every slitless spectrograph. The probability for such overlaps in the GAIA RVS spectrograph focal plane is estimated using photometric observations of 66 stellar fields, mostly close to the Galactic plane. It is shown that overlaps of bright stars (V<17) are common near the Galactic plane, and no spectrum is free from superpositions of faint star tracings. Most overlappers are of spectral type K.

Zwitter, Tomaz; Henden, Arne

2003-01-01

347

Focal adhesion signaling in breast cancer treatment  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Understanding the molecular mechanisms of survival and migratory pathways in cancer cells is essential to better comprehending cancer progression, metastasis formation and drug resistance, thereby benefiting the development of novel anticancer treatments. The overall goal of the work is to better understand the role and mechanism of focal adhesion mediated signaling in the control of anticancer drug-related survival signaling of breast tumor cells in vivo as well as the regulation of cell mig...

Ma, Yafeng

2009-01-01

348

Focal Cortical Dysplasia and Epilepsy Surgery  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Focal cortical dysplasia (FCD) is the most commonly encountered developmental malformation that causes refractory epilepsy. With advances in neuroimaging techniques, in particular MRI, recent studies have revealed a higher prevalence of FCD than previously estimated and have improved the preoperative identification and classification of these abnormalities. However, MRI frequently does not show any abnormalities in patients with pathologically proven FCD. In this situation, functional neuroim...

Lee, Sang Kun; Kim, Dong-wook

2013-01-01

349

On the main stages of the history of intra-articular therapy  

Directory of Open Access Journals (Sweden)

Full Text Available In this review the main stages in the history of intra-articular therapy of the rheumatic diseases are summarized. The first approach to such a local treatment has been likely performed in 1792 by the French physician Jean Gay, who injected in a swelling knee the “eau du Goulard” (Goulard’s water, namely a mixture based on lead compounds. In the XIX century iodine derivatives have been mainly applied as an intra-articular treatment. In the XX century, before the wide use of intra-articular corticosteroids, chiefly due to the Joseph Lee Hollander’s experiences, a variety of drugs has been employed, including cytostatics and sclerosing substances. A further important stage has been synoviorthesis, by using specific radionuclides, that would actually represent an anti-synovial treatment. In the last years a spread use of intra-articular hyaluronic acid, particularly in osteoarthritis, has been recorded, with the aim to warrant articular viscosupplementation. Future of intra-articular treatment should be represented by the biological drugs, i.e., anti-TNF, but it is still untimely to define the exact role of such a local treatment of arthritis.

L. Punzi

2011-09-01

350

Acercamiento a la mecanobiología del cartílago articular a través de un modelo computacional Approach to mechanobiology of articular cartilage through a computation model  

Directory of Open Access Journals (Sweden)

Full Text Available El cartílago articular es un complejo tejido biológico que recubre los extremos de las articulaciones diartrodiales y proporciona resistencia a la compresión y excelentes propiedades de fricción durante el movimiento articular. La presencia de cargas mecánicas influye en el comportamiento y condición fisiológica del cartílago. Es así como, mediante el mecanismo de mecanotrasducción, los condrocitos perciben la magnitud de la carga y a partir de éste estímulo mecánico expresan genes como el Sox9 o el Runx2, los cuales generan cambios bioquímicos en las células y por tanto en el cartílago mismo. Diferentes trabajos experimentales se reportan acerca del efecto de las cargas impuestas al cartílago relacionadas con la expresión morfogénica del condrocito, sin embargo, no se cuenta con un modelo matemático y/o computacional que pueda explicar el comportamiento antagónico del Sox9 y el Runx2. El objetivo de este trabajo es introducir un modelo matemático que permita predecir el comportamiento mecano-biológico del cartílago articular a partir de las cargas mecánicas cíclicas, la presión hidrostática y la expresión génica y/o de proteínas que facilitan el proceso de síntesis o destrucción del tejido. El modelo se implementó numéricamente con el uso del método de los elementos finitos y los resultados obtenidos permitieron predecir diversos comportamientos mecano-biológicos del cartílago articular.Articular cartilage is a biological tissue complex coating the extremes of diarthric joints and provides resistance to compression and excellent friction properties during the articular movement. Presence of mechanical stress influenced on the behavior and physiologic condition of cartilage. That is how by means of the mechanotransduction, the chondrocytes may to perceive the stress magnitude and from this mechanical stimulus, they express gens like the Sox9 or the Runx2, which generate biochemical changes in cells and thus in the cartilage. Different experimental papers reporting on the effect of the stress imposed on the cartilage related to chondrocytes morphogenetic expression, however, there are not a mathematical model and/or computation to explain the antagonist behavior of Sox9 and the Runx2. The aim of present paper is to introduce a mathematical model allows predicting the mechano-biological behavior of articular cartilage from the cyclic mechanic stress, the hydrostatic pressure and the genic expression and or proteins providing the tissue synthesis or destruction. Model was numerically implemented using the finite elements method and the results obtained allowed to predict different mechano-biological behaviors of articular cartilage.

Nancy Stella Landínez Parra

2010-03-01

351

Acercamiento a la mecanobiología del cartílago articular a través de un modelo computacional / Approach to mechanobiology of articular cartilage through a computation model  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish El cartílago articular es un complejo tejido biológico que recubre los extremos de las articulaciones diartrodiales y proporciona resistencia a la compresión y excelentes propiedades de fricción durante el movimiento articular. La presencia de cargas mecánicas influye en el comportamiento y condició [...] n fisiológica del cartílago. Es así como, mediante el mecanismo de mecanotrasducción, los condrocitos perciben la magnitud de la carga y a partir de éste estímulo mecánico expresan genes como el Sox9 o el Runx2, los cuales generan cambios bioquímicos en las células y por tanto en el cartílago mismo. Diferentes trabajos experimentales se reportan acerca del efecto de las cargas impuestas al cartílago relacionadas con la expresión morfogénica del condrocito, sin embargo, no se cuenta con un modelo matemático y/o computacional que pueda explicar el comportamiento antagónico del Sox9 y el Runx2. El objetivo de este trabajo es introducir un modelo matemático que permita predecir el comportamiento mecano-biológico del cartílago articular a partir de las cargas mecánicas cíclicas, la presión hidrostática y la expresión génica y/o de proteínas que facilitan el proceso de síntesis o destrucción del tejido. El modelo se implementó numéricamente con el uso del método de los elementos finitos y los resultados obtenidos permitieron predecir diversos comportamientos mecano-biológicos del cartílago articular. Abstract in english Articular cartilage is a biological tissue complex coating the extremes of diarthric joints and provides resistance to compression and excellent friction properties during the articular movement. Presence of mechanical stress influenced on the behavior and physiologic condition of cartilage. That is [...] how by means of the mechanotransduction, the chondrocytes may to perceive the stress magnitude and from this mechanical stimulus, they express gens like the Sox9 or the Runx2, which generate biochemical changes in cells and thus in the cartilage. Different experimental papers reporting on the effect of the stress imposed on the cartilage related to chondrocytes morphogenetic expression, however, there are not a mathematical model and/or computation to explain the antagonist behavior of Sox9 and the Runx2. The aim of present paper is to introduce a mathematical model allows predicting the mechano-biological behavior of articular cartilage from the cyclic mechanic stress, the hydrostatic pressure and the genic expression and or proteins providing the tissue synthesis or destruction. Model was numerically implemented using the finite elements method and the results obtained allowed to predict different mechano-biological behaviors of articular cartilage.

Nancy Stella, Landínez Parra; Diego Alexander, Garzón Alvarado; Juan Carlos, Vanegas Acosta.

2010-03-01

352

Development of a cell-free, threedimensional implant for the treatment of defects of cartilage-like tissues  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The objective of the presented studies was the development of a cell-free implant, inducing the migration of precursor cells from the adjacent tissue or bone marrow by chemoattractive substances. Subsequently, these cells should be stimulated to differentiate and generate cartilage like repair tissue. Possible applications of such cell-free implants are the treatment of articular cartilage defects, for example of the knee or the substitution of the nucleus pulposus after its exstirpation. ...

Haberstroh, Kathrin

2010-01-01

353

Biphasic indentation of articular cartilage--I. Theoretical analysis.  

Science.gov (United States)

A mathematical solution has been obtained for the indentation creep and stress-relaxation behavior of articular cartilage where the tissue is modeled as a layer of linear KLM biphasic material of thickness h bonded to an impervious, rigid bony substrate. The circular (radius = a), plane-ended indenter is assumed to be rigid, porous, free-draining, and frictionless. Double Laplace and Hankel transform techniques were used to solve the partial differential equations. The transformed equations and boundary conditions yielded an integral equation of the Fredholm type which was analyzed asymptotically and solved numerically. Our asymptotic analyses showed that the linear KLM biphasic material behaves like an incompressible (v = 0.5) single-phase elastic solid at t = 0+; the instantaneous response of the material is governed by the shear modulus (mu s) of the solid matrix. The linear KLM biphasic material behaves like a compressible elastic solid with material properties defined by those of the solid matrix, i.e. (lambda s, mu s) or (mu s, v s) as t----infinity. The transient viscoelastic creep and stress-relaxation behavior, 0 less than t less than infinity, of this material is controlled by the frictional drag (which is inversely proportional to the permeability k) associated with the flow of the interstitial fluid through the porous-permeable solid matrix. For given values of the Poisson's ratio of the solid matrix v s and the aspect ratio a/h, where a is the radius of the indenter and h is the thickness of the layer, the creep behavior with respect to the dimensionless time H Akt/a2 is completely controlled by the load parameter P/2 mu sa2 and the stress relaxation behavior is completely controlled by the rate of compression parameter R0 = kH A/V0h where H A = lambda s + 2 mu s and the equilibrium strain u0/h. This mathematical solution may now be used to describe an indentation experiment on articular cartilage to determine the intrinsic material properties of the tissue, i.e. permeability k, and the elastic coefficients of the solid phase (lambda s, mu s) or (mu s, v s). PMID:3654668

Mak, A F; Lai, W M; Mow, V C

1987-01-01

354

Low-intensity pulsed ultrasound promotes chondrogenic progenitor cell migration via focal adhesion kinase pathway.  

Science.gov (United States)

Low-intensity pulsed ultrasound (LIPUS) has been studied frequently for its beneficial effects on the repair of injured articular cartilage. We hypothesized that these effects are due to stimulation of chondrogenic progenitor cell (CPC) migration toward injured areas of cartilage through focal adhesion kinase (FAK) activation. CPC chemotaxis in bluntly injured osteochondral explants was examined by confocal microscopy, and migratory activity of cultured CPCs was measured in transwell and monolayer scratch assays. FAK activation by LIPUS was analyzed in cultured CPCs by Western blot. LIPUS effects were compared with the effects of two known chemotactic factors: N-formyl-methionyl-leucyl-phenylalanine (fMLF) and high-mobility group box 1 (HMGB1) protein. LIPUS significantly enhanced CPC migration on explants and in cell culture assays. Phosphorylation of FAK at the kinase domain (Tyr 576/577) was maximized by 5 min of exposure to LIPUS at a dose of 27.5 mW/cm(2) and frequency of 3.5 MHz. Treatment with fMLF, but not HMBG1, enhanced FAK activation to a degree similar to that of LIPUS, but neither fMLF nor HMGB1 enhanced the LIPUS effect. LIPUS-induced CPC migration was blocked by suppressing FAK phosphorylation with a Src family kinase inhibitor that blocks FAK phosphorylation. Our results imply that LIPUS might be used to promote cartilage healing by inducing the migration of CPCs to injured sites, which could delay or prevent the onset of post-traumatic osteoarthritis. PMID:24612644

Jang, Kee W; Ding, Lei; Seol, Dongrim; Lim, Tae-Hong; Buckwalter, Joseph A; Martin, James A

2014-06-01

355

ACTIVITY OF CANONICAL WNT SIGNAL SYSTEM IN HYALINE CARTILAGE ARTICULAR CHONDROCYTES IN PROCESS OF SYNOVIAL JOINT DEVELOPMENT  

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Full Text Available Canonical and non-canonical Wnt systems are essential regulators of chondrogenesis and bone development. However, the roles of these systems in synovial joint development are not well studied. To determine if canonical Wnt system is active in developing articular chondrocytes we used immunohistochemistry for ?-galactosidase and doublecortin (cell-type specific marker for articular chondrocytes to double label sections through joint regions of E14.5, E18.5, P10 and adult mice. Here the following results are presented. Canonical Wnt signal system does not work in developing articular chondrocytes at early embryonic stages (E14.5; it is active in the articular chondrocytes at late embryonic stages (E16.5-E18.5 and during postnatal development (P7-P10, but is turned off again in the adult articular chondrocytes. These results suggest that canonical Wnt signaling is being regulated during articular chondrocytes differentiation and joint formation.

A.O. Molotkov

2009-03-01

356

Mapping the Articular Contact Area of the Long Head of the Biceps Tendon on the Humeral Head  

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The purpose of this investigation was to calculate the contact surface area of the long head of the biceps (LHB) in neutral position and abduction. We sought to determine whether the LHB articulates with the humeral head in a consistent pattern comparing articular contact area in neutral position and abduction. Eleven fresh frozen matched cadaveric shoulders were analyzed. The path of the biceps tendon on the articular surface of the humeral head and the total articular surface were digitized...

Morris, Brent J.; Byram, Ian R.; Lathrop, Ray A.; Dunn, Warren R.; Kuhn, John E.

2014-01-01

357

[Quantitative measurement of articular cartilage quality using MRI].  

Science.gov (United States)

'Delayed gadolinium-enhanced MRI of cartilage' (dGEMRIC) and 'T2 mapping' are novel MRI techniques to quantitatively measure the quality of articular cartilage. The advantage of these novel techniques is that they are able to detect the loss of important composites of cartilage before damage to and deformities of the cartilage become visible on radiographs or on conventional MRI. These novel MRI techniques can be used to investigate the effectiveness of potentially preventative or disease-modifying therapy at an early stage of cartilage disease, e.g. in osteoarthritis. It is possible that in the future dGEMRIC and T2 mapping will be used in routine clinical practice to diagnose osteoarthritis at an earlier stage and to predict disease progression. However, much more research is still needed. At the Erasmus Medical Center in Rotterdam, the Netherlands, work is being carried out on the validation, implementation and translation into clinical practice of these and other novel techniques of quantitative measurement of cartilage quality. PMID:24004925

van Tiel, Jasper; Oei, Edwin H G

2013-01-01

358

In vitro ovine articular chondrocyte proliferation: experiments and modelling.  

Science.gov (United States)

This study focuses on analysis of in vitro cultures of chondrocytes from ovine articular cartilage. Isolated cells were seeded in Petri dishes, then expanded to confluence and phenotypically characterized by flow cytometry. The sigmoidal temporal profile of total counts was obtained by classic haemocytometry and corresponding cell size distributions were measured electronically using a Coulter Counter. A mathematical model recently proposed (1) was adopted for quantitative interpretation of these experimental data. The model is based on a 1-D (that is, mass-structured), single-staged population balance approach capable of taking into account contact inhibition at confluence. The model's parameters were determined by fitting measured total cell counts and size distributions. Model reliability was verified by predicting cell proliferation counts and corresponding size distributions at culture times longer than those used when tuning the model's parameters. It was found that adoption of cell mass as the intrinsic characteristic of a growing chondrocyte population enables sigmoidal temporal profiles of total counts in the Petri dish, as well as cell size distributions at 'balanced growth', to be adequately predicted. PMID:20412130

Mancuso, L; Liuzzo, M I; Fadda, S; Pisu, M; Cincotti, A; Arras, M; La Nasa, G; Concas, A; Cao, G

2010-06-01

359

Stress relaxation behaviors of articular cartilages in porcine temporomandibular joint.  

Science.gov (United States)

In this study, we tested the compressive stress relaxation behaviors of the mandibular condylar and temporal cartilages in the porcine temporomandibular joint (TMJ). The aim was to determine the quantitative and qualitative similarities and differences of compressive stress relaxation behaviors between the two cartilages. Ten porcine TMJs were used; the articular surface was divided into 5 regions: anterior, central, posterior, lateral and medial. Compressive relaxation test was carried out at a strain level of 5% in each region of the two cartilages. The stress relaxation was monitored over a period of 5min. In all the regions of the two cartilages, the time-dependent stress relaxation curves showed a marked drop in stress within the initial 10s, which can be fitted by a standard linear viscoelastic model. The instantaneous moduli in the temporal cartilage were dominantly larger than those in the condylar cartilage, while the condylar cartilage had slightly larger relaxation moduli than the temporal cartilage except for the medial region. The both cartilages showed the regional differences in the compressive stress relaxation behavior, and in the temporal cartilage the lateral and medial regions revealed the largest values for the instantaneous and relaxation moduli. The present results demonstrate that the viscoelastic properties of compressive stress relaxation in both cartilages are region-specific, which might have an important implication for stress distribution and transmission along with the TMJ disc. PMID:24680920

Tanaka, Eiji; Pelayo, Fernández; Kim, Namhee; Lamela, María Jesús; Kawai, Nobuhiko; Fernández-Canteli, Alfonso

2014-05-01

360

Intracortical chondroblastoma mimicking intra-articular osteoid osteoma  

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We report a case of intra-articular intracortical chondroblastoma of the femoral condyle which radiologically appeared to be osteoid osteoma. A 19-year-old woman presented with a 3-year history of gradually increasing pain in the right knee and had been on nonsteroidal anti-inflammatory drugs for pain relief. Laboratory data were within normal limits. Radiographs showed a well-demarcated lucent lesion in the medial condyle of the right femur. A nidus-like lesion with calcifications and a sclerotic rim located in the cortex was imaged by computed tomography scan. Magnetic resonance imaging revealed bone marrow edema and soft tissue swelling around the lesion, with low signal intensity of the nidus-like lesion on both T1- and T2-weighted images. The lesion was excised en bloc and the histological diagnosis of chondroblastoma was made. A mild inflammatory reaction was observed in the bone marrow and synovium around the tumor. The chondroblastoma cells were shown to express cyclooxygenase-2 with immunohistochemistry. (orig.)

Ishida, Tsuyoshi; Mukai, Kiyoshi [First Department of Pathology, Tokyo Medical University, Shinjuku 6-1-1, Shinjuku-ku, Tokyo 160-8402 (Japan); Goto, Takahiro [Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, Tokyo (Japan); Motoi, Noriko [Department of Pathology, Toranomon Hospital, Tokyo (Japan)

2002-10-01

 
 
 
 
361

MRI demonstration of hypertrophic articular cartilage repair in osteoarthritis  

International Nuclear Information System (INIS)

Transection of the anterior cruciate ligament in the dog produces changes in the unstable joint typical of osteoarthritis, although full-thickness catilage ulceration is rare. Information concerning the late fate of the cartilage after transection is meager. In the present study magnetic resonance imaging (MRI) was used to evaluate cartilage abnormalities 3 years after transection. Plain radiographs of the osteoarthritic and contralateral knees were obtained serially. MRI was performed 3 years after anterior cruciate ligament transection, at which time all three animals exhibited knee instability. Radiographs of the osteoarthritic knees showed osteophytes and subchondral sclerosis with progression between 2 and 3 years. On MRI, articular cartilage margins in the knee were indistinct, and the cartilage was thicker than that in the contralateral knee (maximum difference = 2.7 mm). This increase in thickness is consistent with biochemical data from dogs killed up to 64 weeks after creation of knee instability, which showed marked increases in cartilage bulk and in proteoglycan synthesis and concentration. The findings emphasize that increased matrix synthesis after anterior cruciate ligament transection leads to functional cartilage repair sustained even in the presence of persistent alteration of joint mechanics. (orig.)

362

Proteoglycon synthesis by articular chondrocytes in agarose culture  

International Nuclear Information System (INIS)

Articular chondrocytes were isolated from knee joints of full-term bovine foetuses and grown in long-term agarose cultures. At intervals, cultures were labelled with 35S-[sulphate] or D[6-3H] glucosamine. Newly synthesized proteoglycans were extracted with 4 M guanidine HCl and purified by isopycnic density gradient centrifugation or on DEAE cellulose in the presence of 8 M urea. Characterization of the proteoglycans revealed them to be identical in size to those present in the tissue and to be similarly capable of aggregation with hyaluronate. Newly synthesized chondroitin sulphate chains were identical in size, but newly synthesized keratan sulphate chains were somewhat larger than those present in the tissue. The newly synthesized proteoglycans were shown to contain the same range of O-linked oligosaccharides identified in proteoglycans of the Swarm rat chondrosarcoma. Cartilage-specific proteoglycan continued to be synthesized by the chondrocytes for up to 60 days; however, with time, proportionately more of a small non-aggregating proteoglycan appeared

363

Extra-articular manifestations of rheumatoid arthritis: An update.  

Science.gov (United States)

Rheumatoid arthritis (RA) is an immune-mediated disease involving chronic low-grade inflammation that may progressively lead to joint destruction, deformity, disability and even death. Despite its predominant osteoarticular and periarticular manifestations, RA is a systemic disease often associated with cutaneous and organ-specific extra-articular manifestations (EAM). Despite the fact that EAM have been studied in numerous RA cohorts, there is no uniformity in their definition or classification. This paper reviews current knowledge about EAM in terms of frequency, clinical aspects and current therapeutic approaches. In an initial attempt at a classification, we separated EAM from RA co-morbidities and from general, constitutional manifestations of systemic inflammation. Moreover, we distinguished EAM into cutaneous and visceral forms, both severe and not severe. In aggregated data from 12 large RA cohorts, patients with EAM, especially the severe forms, were found to have greater co-morbidity and mortality than patients without EAM. Understanding the complexity of EAM and their management remains a challenge for clinicians, especially since the effectiveness of drug therapy on EAM has not been systematically evaluated in randomized clinical trials. PMID:21939785

Prete, Marcella; Racanelli, Vito; Digiglio, Liboria; Vacca, Angelo; Dammacco, Franco; Perosa, Federico

2011-12-01

364

Automated classification of articular cartilage surfaces based on surface texture.  

Science.gov (United States)

In this study the automated classification system previously developed by the authors was used to classify articular cartilage surfaces with different degrees of wear. This automated system classifies surfaces based on their texture. Plug samples of sheep cartilage (pins) were run on stainless steel discs under various conditions using a pin-on-disc tribometer. Testing conditions were specifically designed to produce different severities of cartilage damage due to wear. Environmental scanning electron microscope (SEM) (ESEM) images of cartilage surfaces, that formed a database for pattern recognition analysis, were acquired. The ESEM images of cartilage were divided into five groups (classes), each class representing different wear conditions or wear severity. Each class was first examined and assessed visually. Next, the automated classification system (pattern recognition) was applied to all classes. The results of the automated surface texture classification were compared to those based on visual assessment of surface morphology. It was shown that the texture-based automated classification system was an efficient and accurate method of distinguishing between various cartilage surfaces generated under different wear conditions. It appears that the texture-based classification method has potential to become a useful tool in medical diagnostics. PMID:17236517

Stachowiak, G P; Stachowiak, G W; Podsiadlo, P

2006-11-01

365

Intracortical chondroblastoma mimicking intra-articular osteoid osteoma  

International Nuclear Information System (INIS)

We report a case of intra-articular intracortical chondroblastoma of the femoral condyle which radiologically appeared to be osteoid osteoma. A 19-year-old woman presented with a 3-year history of gradually increasing pain in the right knee and had been on nonsteroidal anti-inflammatory drugs for pain relief. Laboratory data were within normal limits. Radiographs showed a well-demarcated lucent lesion in the medial condyle of the right femur. A nidus-like lesion with calcifications and a sclerotic rim located in the cortex was imaged by computed tomography scan. Magnetic resonance imaging revealed bone marrow edema and soft tissue swelling around the lesion, with low signal intensity of the nidus-like lesion on both T1- and T2-weighted images. The lesion was excised en bloc and the histological diagnosis of chondroblastoma was made. A mild inflammatory reaction was observed in the bone marrow and synovium around the tumor. The chondroblastoma cells were shown to express cyclooxygenase-2 with immunohistochemistry. (orig.)

366

A study of crystalline biomaterials for articular cartilage bioengineering  

International Nuclear Information System (INIS)

This study examines the suitability of marine origin coral species, Porites lutea (POR) and the hydrozoan Millepora dichotoma (MIL), for use as novel three dimensional growth matrices in the field of articular cartilage tissue engineering. Therefore, mesenchymal stem cells (MSCs) and chondrocytes were grown on the skeletal material obtained from each of these two organisms to investigate their potential use as three dimensional scaffolding for cartilage tissue growth. Chondrogenic induction of MSCs was achieved by addition of transforming growth factor-?1 (TGF-?1) and insulin growth factor-I (IGF-I). Cell adherence, proliferation, differentiation and tissue development were investigated through six weeks of culture. Cartilage tissue growth and chondrocytic phenotype maintenance of each cell type were examined by cell morphology, histochemical analyses, expression of collagen type II and quantitative measures of glycosaminoglycan (GAG) content. The MSCs and the chondrocytes were shown good adherence to the scaffolds and maintenance of the chondrocytic phenotype in the initial stages of culture. However after two weeks of culture on MIL and three weeks on POR these cultures began to exhibit signs of further differentiation and phenotypic loss. The shown results indicated that POR was a better substrate for chondrocytes phenotype maintenance than MIL. We believe that surface modification of POR combined with mechanical stimuli will provide a suitable environment for chll provide a suitable environment for chondrogenic phenotype maintenance. Further investigation of POR and other novel coralline biomatrices is indicated and warranted in the field of cartilage tissue engineering applications

367

The effect of intra-articular hydrocortisone injections on healthy rat joints. Pt. 1. Incorporation of 35S sulphates into glucosaminoglycans of articular connective tissue  

International Nuclear Information System (INIS)

Using 35S sodium sulphate the changes in connective tissue glucosaminoglycans were studied in knee joints of rats after topical injections of hydrocortisone. It was demonstrated that the incorporation of sodium sulphate into articular connective tissue glucosaminoglycans was raised in relation to control animals. The possible mechanisms responsible for the increase in the content of glucosaminoglycans after intraaricular injections of hydrocortisone are discussed. (author)

368

Intra-articular gouty tophi of the knee: CT and MR imaging in 12 patients  

International Nuclear Information System (INIS)

Objective. To define the imaging characteristics of intra-articular tophi of the knee. Design and patients. Twelve patients with intra-articular tophi in the knee were studied with routine MR imaging, gadolinium (Gd)-enhanced MR imaging, and CT over a 4-year period. There were 11 men and one woman, 25-82 years of age (mean age 48 years). Four patients did not have a documented history of gout at the time of the MR examination. The diagnosis of intra-articular tophi was provided by arthroscopy and histological examination (5 patients), by microscopic study of joint fluid (5 patients), or by characteristic clinical, laboratory and imaging findings (2 patients). Results. In 15 MR examinations the tophi were located purely intra-articularly in 10 knees. In the remaining five MR studies, periarticular soft tissues or bone, or both, were involved. All the intra-articular tophi manifested low to intermediate signal intensity on both T1- and T2-weighted images. All five Gd-enhanced MR examinations demonstrated a heterogeneous peripheral enhancement. All 10 CT scans showed varying degrees of stippled calcifications within the tophi. The nature of the calcifications was confirmed on histological examination in three patients. Conclusion. Presenting clinical manifestations of gout may relate to intra-articular tophaceous deposits. Such deposits present as masses on MR images with low to intermediate signal intensity on both T1- and T2-weighted images and a characteristic enhanceighted images and a characteristic enhancement pattern following intravenous Gd administration. These features relate primarily to internal calcifications, which are most evident on CT images. MR evaluation (including Gd administration) supplemented, in some cases, with CT scanning allows accurate diagnosis of intra-articular tophaceous deposits. (orig.)

369

Usefulness of fluoroscopy-guided intra-articular injection of the knee  

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To determine the accuracy of the intra-articular location of hyaluronic acid injection using a blind approach and to establish the usefulness of fluoroscopy-guided intra-articular injection. A fluoroscopy unit was used for 368 intra-articular injections of hyaluronic acid to 93 knees in 65 patients. Initially, blind needle positioning was conducted on the fluoroscopy table. The failure rate of the blind approach among the 368 injections was evaluated, and a relationship between the Kellgren-Lawrence grade (K-L grade) and the incidence of repeated failures using the blind approach was determined for injections to 52 knees in 37 patients who received a complete cycle of injections (five consecutive injections with a one-week interval between injections). Using a blind approach, 298 of 368 trials (81.2%) resulted in a needle tip being placed in an intra-articular location, while 70 of 368 trials resulted in an extra-articular placement of the needle tip. Among 52 knees to which a complete cycle of injection (five consecutive injections with a one-week interval between injections) was administered, repeated failure of intra-articular placement using the blind approach was seen for 18 knees (34.6%); a more severe K-L grade assigned was associated with a higher rate of repeated failure. However, the trend was not statistically significant based on the Chi-squared test ({rho} value = 0.14). Fluoroscopy-guided needle placement may be helpful to ensure therapeutic intra-articular injection of the knee.

Myung, Jae Sung; Lee, Joon Woo [Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Lee, Ji Yeon [Kangwon National University College of Medicine, Chuncheon (Korea, Republic of)] (and others)

2007-06-15

370

Effects of freezing rates and cryoprotectant on thermal expansion of articular cartilage during freezing process.  

Science.gov (United States)

The intact articular cartilage has not yet been successfully preserved at low temperature most likely due to the volume expansion from water to ice during freezing. The objective of this current study focuses on examining thermal expansion behavior of articular cartilage (AC) during freezing from 0 degree C to -100 degree C. Thermo Mechanical Analysis (TMA) was used to investigate the effects of different concentrations of dimethyl sulphoxide (DMSO) (0%, 10%, 30% and 60% v/v) and different freezing rates (1 C/min, 3 C/min and 5 C/min). The results showed that: (1) the inhomogeneous thermal expansion (or contraction) presents due to inhomogeneous water distributions in articular cartilage during freezing, which also may be the most likely reason that the matrix has been damaged in cryopreserved intact articular cartilage; (2) at the phase transition temperature range, the maximum thermal strain change value for 5C/min is approximately 1.45 times than that for 1 C/min, but the maximum thermal expansion coefficient of the later is about six times than that of the former; (3) the thermal expansion coefficient decreases with increasing cooling rate at the unfrozen temperature region, but some opposite results are obtained at the frozen temperature region; (4) the higher the DMSO concentration is, at the phase change temperature region, the smaller the thermal strain change as well as the maximum thermal expansion coefficient are, but DMSO concentration exhibits little effect on the thermal expansion coefficient at both unfrozen and frozen region. Once the DMSO concentration increasing enough, e.g. 60% v/v, the thermal strain decreases linearly and smoothly without any abrupt change due to little or no ice crystal forms (i.e. vitrification) in frozen articular cartilage. This study may improve our understanding of the thermal expansion (or contraction) behavior of cryopreserved articular cartilage and it may be useful for the future study on cryopreservation of intact articular cartilage. PMID:23995399

Xu, Y; Sun, H J; Lv, Y; Zou, J C; Lin, B L; Hua, T C

2013-01-01

371

99mTc-RBC Hepatic Scintiscan in focal Hepatic Lesions  

International Nuclear Information System (INIS)

39 patients with focal hepatic lesions were evaluated by 99mTc-RBC liver scan. The diagnosis of focal hepatic lesions were made by percutaneous needle biopsy, angiography, surgery, or clinical courses. These diagnoses included 24 cases of hemangioma, 7 hepatomas, 6 metastatic disease, 1 abscess, and 1 cyst. 19 hemangiomas showed focal hot activity on delayed static planar images. 3 small deep seated hemangiomas were diagnosed by SPECT that would have been missed by planar images alone. 2 large hemangiomas had no radioisotope uptake within the lesions on delayed images and at surgery cavernous hemangioma with thrombosis, calcification, and fibrosis were found. For hepatic hemangiomas in our series, the sensitivity was 91.7% and the specificity was 100%. The remaining 15 patients including hepatomas, metastatic lesions, cyst and abscess showed cold defect on delayed blood pool images. It is concluded that99mTc-RBC liver scan should be the choice of primary diagnostic procedure for clinically suspected hepatic hemangioma since its inexpensive, non-invasive, and readily available.

372

Diagnostic procedures in focal nodular hyperplasia (FNH)  

International Nuclear Information System (INIS)

The random finding of an echo-producing focal hepatic lesion, which is revealed in an otherwise healthy liver in connection with diagnostic procedures in the epigastric region, requires a carefully planned strategy that is determined by its ultrasonic morphology. As a general rule, any focal lesion randomly detected by sonography necessitates more thorough examination on the basis of computed tomography. The only exception here are lesions that are compatible with the typical appearance of cysts and do not produce echoes as well as liver tumours of a diameter of less than 2 cm, which are characterised by rich homogeneous echoes increasing in the dorsal direction. While the former belong to the range of cystic disorders, the latter are, in all probability, to be classified with hepatic hemangiomas. There is no immediate need for those lesions to be examined in more detail, even though sonographic follow-ups should be carried out. In view of the fact that any solid focal lesion detected in an otherwise healthy liver may theoretically be a FNH, steps must be taken for its diagnostic distinction from other hepatic foci. This may be achieved by dynamic computed tomography following intravenous injection of a bolus of contrast medium. Should the information thus obtained still not permit a FNH or hepatic hemangioma to be diagnosed, it will be inevitable to use radionuclide function studies. As a last resort, punch biopsy samples may be obtained to establish a firm diagnosis be obtained to establish a firm diagnosis. The clinical value of magnetic resonance tomography is still open to discussion. (orig.)

373

Morphological Characteristics of the Temporomandibular Joint Articular Surfaces in Patients with Temporomandibular Disorders / Características Morfológicas de las Superficies Articulares de la Articulación Temporomandibular de Pacientes con Trastornos Temporomandibulares  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in spanish El conocimiento de las características anatómicas de las superficies articulares de la articulación temporomandibular (ATM) es fundamental para que clínicos y odontólogos reconozcan las alteraciones morfológicas que ocurren en la articulación de pacientes con trastornos temporomandibulares (TTM). Di [...] versos investigadores asocian los TTMs con alteraciones en las superficies articulares de la ATM. La identificación de los cambios óseos relacionados con la ATM es crítica, ya que estos se asocian a signos y síntomas de TTM, y el conocimiento de estos es fundamental para el correcto diagnóstico y adecuada planificación de tratamiento. El objetivo fue analizar las características morfológicas de las superficies articulares de la ATM en pacientes con diagnóstico de TTM, diagnosticado de acuerdo a los Criterios Diagnósticos para Investigación de los Trastornos Temporomandibulares (CDI/TTM), junto con analizar la relación existente entre incremento de edad-osteoartrosis. Fueron seleccionados 19 pacientes, 17 mujeres y 2 hombres, de la Unidad de Trastornos Cráneo Cérvico Mandibulares (UCRACEM) - Universidad de Talca, Chile. La evaluación imagenológica se realizó mediante el examen de Tomografía Computarizada Cone-Beam (TCCB). En el análisis de las superficies articulares, 11 (28,94%) presentaron morfología normal. Los cambios óseos encontrados fueron: esclerosis, aplanamiento de la cabeza de la mandíbula, erosión, osteoartrosis, osteofitos y quiste subcondral. Hubo relación estadística significativa entre incremento de edad-osteoartrosis (p=0,00). Nuestros hallazgos nos permiten concluir que los cambios óseos en las caras articulares de la ATM en pacientes con TTM son frecuentes, y la esclerosis el hallazgo más común. También se encontró asociación entre incremento de edad y osteoartrosis. Abstract in english The knowledge of the anatomical characteristics of the temporomandibular joint (TMJ) articular surfaces is essentital to enable physicians and dentists to recognize the morphological changes that occur in this articulation in patients with temporomandibular disorders (TMD). Several researchers assoc [...] iate the TMD with changes of TMJ articular surfaces. The careful identification of bone changes related to TMJ is critical, since these abnormalities are associated with signs and symptoms of TMD and the knowledge of TMD signs and symptoms is fundamental for correctly diagnosing and for adequate treatment planning. The aim of this study was to evaluate the morphological characteristics of the TMJ articular surfaces in patients with TMD diagnosed according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). In addition, therelationship between increasing age-osteoarthrosis was evaluated. For the sample we selected 19 patients, 17 female and 2 male, referred to the "Unidad de Trastornos Cráneo Cérvico Mandibulares (UCRACEM) - Universidad de Talca, Chile". The imaging assessment was carried out by Cone-Beam Computed Tomography (CBCT). In the imaging analysis of the articular surfaces 11 joints (28.94%) showed normal morphology. The bone changes found were: sclerosis, flattening, erosion, osteoarthrosis, osteophytes, subcondral cysts. We found statistically significant difference between increasing age-osteoarthrosis (p=0.00). Considering our results we concluded that bone changes of the TMJ articular surfaces in patients with TMD are very common, with sclerosis as the most frequent finding. It was also possible to conclude that there was a significant association between increasing age-osteoarthrosis.

N, Alves; A, Schilling Quezada; A, Gonzalez Villalobos; J, Schilling Lara; N. F, Deana; C, Pastenes Riveros.

1317-13-01

374

Idiopathic focal segmental glomerulosclerosis and HLA antigens  

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The objective of the present study was to investigate a possible association between HLA class II antigens and idiopathic focal segmental glomerulosclerosis (FSGS). HLA-A, -B, -DR and -DQ antigens were determined in 19 Brazilian patients (16 white subjects and three subjects of Japanese origin) with biopsy-proven FSGS. Comparison of the HLA antigen frequencies between white patients and white local controls showed a significant increase in HLA-DR4 frequency among FSGS patients (37.7 vs 17.2%,...

Gerbase-DeLima M.; Pereira-Santos A.; Sesso R.; Temin J.; Aragão E.S.; Ajzen H.

1998-01-01

375

The pathogenesis of focal segmental glomerulosclerosis.  

Science.gov (United States)

Focal segmental glomerulosclerosis (FSGS) is a histologic pattern of injury on kidney biopsy that can arise from a diverse range of causes and mechanisms. Although primary and secondary forms are described based on the underlying cause, there are many common factors that underlie the development of this segmental injury. In this review, we will describe the currently accepted model for the pathogenesis of classic FSGS and review the data supporting this model. Although the podocyte is considered the major target of injury in FSGS, we will also highlight the contributions of other resident glomerular cells in the development of FSGS. PMID:25168829

Jefferson, J Ashley; Shankland, Stuart J

2014-09-01

376

Idiopathic focal segmental glomerulosclerosis and HLA antigens  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The objective of the present study was to investigate a possible association between HLA class II antigens and idiopathic focal segmental glomerulosclerosis (FSGS). HLA-A, -B, -DR and -DQ antigens were determined in 19 Brazilian patients (16 white subjects and three subjects of Japanese origin) with [...] biopsy-proven FSGS. Comparison of the HLA antigen frequencies between white patients and white local controls showed a significant increase in HLA-DR4 frequency among FSGS patients (37.7 vs 17.2%, P

M., Gerbase-DeLima; A., Pereira-Santos; R., Sesso; J., Temin; E.S., Aragão; H., Ajzen.

1998-03-01

377

Permeability factors in focal and segmental glomerulosclerosis.  

Science.gov (United States)

Focal and segmental glomerulosclerosis (FSGS) represents a group of glomerular disorders, identified on kidney biopsy, that progress in the histopathologic pattern of sclerosis in parts of some glomeruli. Damage to podocytes usually marks the beginning of the disease, most evident in primary FSGS. In addition to genetic predisposition, there are many acquired causes that disturb normal podocyte homeostasis and allow for the development of FSGS. The aim of this review was to summarize recent findings of the most relevant circulating permeability factors that may serve as biomarkers of active primary idiopathic FSGS and aid in the diagnosis and prediction of recurrent FSGS after kidney transplantation. PMID:25168830

Reiser, Jochen; Nast, Cynthia C; Alachkar, Nada

2014-09-01

378

Focal inflammatory diseases of the liver  

International Nuclear Information System (INIS)

Inflammatory lesions constitute an important subgroup of focal liver lesions. They may mimic primary or metastatic neoplastic lesions and their differentiation from neoplasia is clinically very important since management of the patient significantly changes. Radiologists should have an important role in both the diagnosis and therapy of these lesions by performing percutaneous aspirations and drainages. In this review we discussed the radiological findings of pyogenic abscesses, amebic abscesses, candidiasis, tuberculosis, hydatic cysts, fascioliasis, ascariasis, schistosomiasis, and sarcoidosis with a special emphasis on US, CT and MR characteristics

379

Focal inflammatory diseases of the liver  

Energy Technology Data Exchange (ETDEWEB)

Inflammatory lesions constitute an important subgroup of focal liver lesions. They may mimic primary or metastatic neoplastic lesions and their differentiation from neoplasia is clinically very important since management of the patient significantly changes. Radiologists should have an important role in both the diagnosis and therapy of these lesions by performing percutaneous aspirations and drainages. In this review we discussed the radiological findings of pyogenic abscesses, amebic abscesses, candidiasis, tuberculosis, hydatic cysts, fascioliasis, ascariasis, schistosomiasis, and sarcoidosis with a special emphasis on US, CT and MR characteristics.

Oto, Aytekin; Akhan, Okan; Oezmen, Mustafa

1999-10-01

380

Psychiatric symptoms associated with focal hand dystonia.  

Science.gov (United States)

Myoclonus dystonia and idiopathic dystonia are associated with a greater frequency of obsessive compulsive disorder (OCD) and major depression. We investigated the frequency of OCD in 39 patients with primary focal hand dystonia (FHD) using a semistructured interview. OCD and subsyndromal OCD was diagnosed in 5 of 39 (12.82%) patients with FHD, whereas OCD occurs in 2.3% of the general population. Recurrent depression occurred in (7 of 39) 17.95% of patients with FHD along with a family history of depression in (16 of 39) 41.02%. Overlapping mechanisms manifesting as FHD may also predispose to OC symptoms and likely implicates a common striatal dysfunction. PMID:20737548

Voon, Valerie; Butler, Tracy R; Ekanayake, Vindhya; Gallea, Cecile; Ameli, Rezvan; Murphy, Dennis L; Hallett, Mark

2010-10-15

 
 
 
 
381

CT diagnosis of focal nodular hyperplasia  

International Nuclear Information System (INIS)

The paper analyses the findings of a CT study of 21 lesions of focal nodular hyperplasia in 17 patients. In addition to subjective valuation of the dynamic studies, densitometric measurements on a time basis were carried out (gamma-fit curves) and a density profile was obtained. These tumour-like lesions show typical density changes with rapid enhancement in the arterial phase and rapid fall in density after one or two minutes. Various patterns of the hyperdense lesions (non-homogeneous, those resembling vessels or homogeneous lesions) may be of significance in differential diagnosis. Atypical density patterns were found particularly in foci projecting from the liver. (orig.)

382

Focal-plane sensor-processor chips  

CERN Document Server

Focal-plane sensor-processor imager devices are sensor arrays and processor arrays embedded in each other on the same silicon chip. This close coupling enables ultra-fast processing even on tiny, low power devices, because the slow and energetically expensive transfer of the large amount of sensory data is eliminated. This technology also makes it possible to produce locally adaptive sensor arrays, which can (similarly to the human retina) adapt to the large dynamics of the illumination in a single scene This book focuses on the implementation and application of state-of-the-art vision chips.

Zarandy, Kos

2011-01-01

383

Characterization of DECam focal plane detectors  

Energy Technology Data Exchange (ETDEWEB)

DECam is a 520 Mpix, 3 square-deg FOV imager being built for the Blanco 4m Telescope at CTIO. This facility instrument will be used for the 'Dark Energy Survey' of the southern galactic cap. DECam has chosen 250 ?m thick CCDs, developed at LBNL, with good QE in the near IR for the focal plane. In this work we present the characterization of these detectors done by the DES team, and compare it to the DECam technical requirements. The results demonstrate that the detectors satisfy the needs for instrument.

Diehl, H.Thomas; Angstadt, Robert; Campa, Julia; Cease, Herman; Derylo, Greg; Emes, John H.; Estrada, Juan; Kibik, Donna; Flaugher, Brenna L.; Holland, Steve E.; Jonas, Michelle; /Fermilab /Madrid, CIEMAT /LBL, Berkeley /Argonne /Pennsylvania U.

2008-06-01

384

Characterization of DECam focal plane detectors  

International Nuclear Information System (INIS)

DECam is a 520 Mpix, 3 square-deg FOV imager being built for the Blanco 4m Telescope at CTIO. This facility instrument will be used for the 'Dark Energy Survey' of the southern galactic cap. DECam has chosen 250 ?m thick CCDs, developed at LBNL, with good QE in the near IR for the focal plane. In this work we present the characterization of these detectors done by the DES team, and compare it to the DECam technical requirements. The results demonstrate that the detectors satisfy the needs for instrument

385

Simulating focal demyelinating neuropathies: membrane property abnormalities.  

Science.gov (United States)

Membrane properties such as potentials (intracellular, extracellular, electrotonic) and axonal excitability indices (strength-duration and charge-duration curves, strength-duration time constants, rheobasic currents, recovery cycles) can now be measured in healthy subjects and patients with demyelinating neuropathies. They are regarded here in two cases of simultaneously reduced paranodal seal resistance and myelin lamellae in one to three consecutive internodes of human motor nerve fiber. The investigations are performed for 70 and 96% myelin reduction values. The first value is not sufficient to develop a conduction block, but the second leads to a block and the corresponding demyelinations are regarded as mild and severe. For both the mild and severe demyelinations, the paranodally internodally focally demyelinated cases (termed as PIFD1, PIFD2, and PIFD3, respectively, with one, two, and three demyelinated internodes) are simulated using our previous double-cable model of the fiber. The axon model consists of 30 nodes and 29 internodes. The membrane property abnormalities obtained can be observed in vivo in patients with demyelinating forms of Guillain-Barré syndrome (GBS) and multifocal motor neuropathy (MMN). The study confirms that focal demyelinations are specific indicators for acquired demyelinating neuropathies. Moreover, the following changes have been calculated in our previous papers: (1) uniform reduction of myelin thickness in all internodes (Stephanova et al. in Clin Neurophysiol 116: 1153-1158, 2005); (2) demyelination of all paranodal regions (Stephanova and Daskalova in Clin Neurophysiol 116: 1159-1166, 2005a); (3) simultaneous reduction of myelin thickness and paranodal demyelination in all internodes (Stephanova and Daskalova in Clin Neurophysiol 116: 2334-2341, 2005b); and (4) reduction of myelin thickness of up to three internodes (Stephanova et al., in J Biol Phys, 2006a,b, DOI: 10.1007/s10867-005-9001-9; DOI: 10.1007/s10867-006-9008-x). The membrane property abnormalities obtained in the homogeneously demyelinated cases are quite different and abnormally greater than those in the case investigated here of simultaneous reduction in myelin thickness and paranodal demyelination of up to three internodes. Our previous and present results show that unless focal demyelination is severe enough to cause outright conduction block, changes are so slight as to be essentially indistinguishable from normal values. Consequently, the excitability-based approaches that have shown strong potential as diagnostic tools in systematically demyelinated conditions may not be useful in detecting mild focal demyelinations, independently of whether they are internodal, paranodal, or paranodal internodal. PMID:17072638

Stephanova, D I; Alexandrov, A S; Kossev, A; Christova, L

2007-02-01

386

Defect production in ceramics  

International Nuclear Information System (INIS)

A review is given of several important defect production and accumulation parameters for irradiated ceramics. Materials covered in this review include alumina, magnesia, spinel, silicon carbide, silicon nitride, aluminum nitride and diamond. Whereas threshold displacement energies for many ceramics are known within a reasonable level of uncertainty (with notable exceptions being AlN and Si3N4), relatively little information exists on the equally important parameters of surviving defect fraction (defect production efficiency) and point defect migration energies for most ceramics. Very little fundamental displacement damage information is available for nitride ceramics. The role of subthreshold irradiation on defect migration and microstructural evolution is also briefly discussed. (orig.)

387

Defect production in ceramics  

International Nuclear Information System (INIS)

A review is given of several important defect production and accumulation parameters for irradiated ceramics. Materials covered in this review include alumina, magnesia, spinel silicon carbide, silicon nitride, aluminum nitride and diamond. Whereas threshold displacement energies for many ceramics are known within a reasonable level of uncertainty (with notable exceptions being AIN and Si3N4), relatively little information exists on the equally important parameters of surviving defect fraction (defect production efficiency) and point defect migration energies for most ceramics. Very little fundamental displacement damage information is available for nitride ceramics. The role of subthreshold irradiation on defect migration and microstructural evolution is also briefly discussed

388

On Holographic Defect Entropy  

CERN Document Server

We study a number of (3+1)- and (2+1)-dimensional defect and boundary conformal field theories holographically dual to supergravity theories. In all cases the defects or boundaries are planar, and the defects are codimension-one. Using holography, we compute the entanglement entropy of a (hemi-)spherical region centered on the defect (boundary). We define defect and boundary entropies from the entanglement entropy by an appropriate background subtraction. For some (3+1)-dimensional theories we find evidence that the defect/boundary entropy changes monotonically under certain renormalization group flows triggered by operators localized at the defect or boundary. This provides evidence that the g-theorem of (1+1)-dimensional field theories generalizes to higher dimensions.

Estes, John; O'Bannon, Andy; Tsatis, Efstratios; Wrase, Timm

2014-01-01

389

Effects of cell concentration and growth period on articular and ear chondrocyte transplants for tissue engineering.  

Science.gov (United States)

This study determined the effects of chondrocyte source, cell concentration, and growth period on cartilage production when isolated porcine cells are injected subcutaneously in a nude mouse model. Chondrocytes were isolated from both ear and articular cartilage and were suspended in Ham's F-12 medium at concentrations of 10, 20, 40, and 80 million cells per cubic centimeter. Using the nude mouse model, each concentration group was injected subcutaneously in 100-microl aliquots and was allowed to incubate for 6 weeks in vivo. In addition, cells suspended at a fixed concentration of 40 million cells per cubic centimeter were injected in 100-microl aliquots and were incubated for 1, 2, 3, 4, 5, 6, 9, and 12 weeks. Each concentration or time period studied contained a total of eight mice, with four samples harvested per mouse for a final sample size of 32 constructs. All neocartilage samples were analyzed by histologic characteristics, mass, glycosaminoglycan level, and DNA content. Control groups consisted of native porcine ear and articular cartilage. Specimen mass increased with increasing concentration and incubation time. Ear neocartilage was larger than articular neocartilage at each concentration and time period. At 40 million cells per cubic centimeter, both ear and articular chondrocytes produced optimal neocartilage, without limitations in growth. Specimen mass increased with incubation time up to 6 weeks in both ear and articular samples. No significant variations in glycosaminoglycan content were found in either articular or ear neocartilage, with respect to variable chondrocyte concentration or growth period. Although articular samples demonstrated no significant trends in DNA content over time, ear specimens showed decreasing values through 6 weeks, inversely proportional to increase in specimen mass. Although both articular and ear sources of chondrocytes have been used in past tissue-engineering studies with success, this study indicates that a suspension of ear chondrocytes injected into a subcutaneous location will produce biochemical and histologic data with greater similarity to those of native cartilage. The authors believe that this phenomenon is attributable to the local environment in which isolated chondrocytes from different sources are introduced. The subcutaneous environment of native ear cartilage accommodates subcutaneously injected ear chondrocyte transplants better than articular transplants. Native structural and biochemical cues within the local environment are believed to guide the proliferation of the differentiated chondrocytes. PMID:11496181

Panossian, A; Ashiku, S; Kirchhoff, C H; Randolph, M A; Yaremchuk, M J

2001-08-01

390

Distance between parapatellar portal and intra-articular space for needle positioning in knee osteoarthritis  

Directory of Open Access Journals (Sweden)

Full Text Available Background: Intra-articular injection is a common therapeutic procedure in osteoarthritis (OA that need high accuracy. This study was aimed to measure the distance between parapatellar skin and intra-articular space as a guidance to choose the length of needle needed to perform intra-articular injection. Methods: Twenty one knees MRI were taken from 16 females with knee osteoarthritis. The length of the needle needed to reach intra-articular space was reconstructed by drawing straight line from skin to intra-articular fluid. Paired t-test was using to analyze the mean difference of measurement of left side compare with right side with significant indicator if p-value < 0.05. Results: The entry point on both medial and lateral parapatellar were more cranial than transverse mid-patellar line. On medial portal, the closest distance from skin to intra-articular space is 27.81 ± 7.58 mm. Mean point of entry is 4.46 ± 2.16 mm cranial to mid-patellar line, and 14.20 ± 4.45 mm posterior to the prominence of medial border of patella. On lateral portal, the closest distance from skin to intra-articular space is 16.84 ± 6.79 mm. Mean point of entry is 11.10 ± 5.94 mm cranial to mid-patellar line, and 8.91 ± 3.83 mm posterior to the prominence of lateral border of patella. Conclusion: MRI knee osteoarthritis study showed that the mean distance between skin and intra-articular joint space of medial portal is 27.81 ± 7.58 mm, and lateral portal is 16.84 ± 6.79 mm. The portals on both sides is cranial to midpoint of patella, lateral appears more proximal than medial. This should be put into consideration in choosing needle length and portal projection to increase intra-articular injection accuracy. (Med J Indones. 2013;22:83-7Keywords: Needle length, osteoarthritis, parapatellar skin portal

John Butarbutar

2013-06-01

391

Fast nonparaxial scalar focal field calculations.  

Science.gov (United States)

An efficient algorithm for calculating nonparaxial scalar field distributions in the focal region of a lens is discussed. The algorithm is based on fast Fourier transform implementations of the first Rayleigh-Sommerfeld diffraction integral and assumes that the input field at the pupil plane has a larger extent than the field in the focal region. A sampling grid is defined over a finite region in the output plane and referred to as a tile. The input field is divided into multiple separate spatial regions of the size of the output tile. Finally, the input tiles are added coherently to form a summed tile, which is propagated to the output plane. Since only a single tile is propagated, there are significant reductions of computational load and memory requirements. This method is combined either with a subpixel sampling technique or with a chirp z-transform to realize smaller sampling intervals in the output plane than in the input plane. For a given example the resulting methods enable a speedup of approximately 800× in comparison to the normal angular spectrum method, while the memory requirements are reduced by more than 99%. PMID:24977358

Hillenbrand, Matthias; Hoffmann, Armin; Kelly, Damien P; Sinzinger, Stefan

2014-06-01

392

Benign focal hepatic lesions; Benigne fokale Leberlaesionen  

Energy Technology Data Exchange (ETDEWEB)

A profound knowledge of the various benign focal hepatic lesions and selection of the most suitable radiological examination modality is essential for achieving an accurate characterization of a hepatic lesion and in turn will determine the further patient management. This will avoid unnecessary agitation to both patient and the referring clinician and limits time-consuming, costly and risky biopsies to an absolute minimum. The following article will discuss the typical and atypical appearances of the most frequent and clinically relevant benign focal hepatic lesions with ultrasound, computed tomography and magnetic resonance imaging. (orig.) [German] Eine genaue Kenntnis des breiten Spektrums benigner fokaler Leberlaesionen und der geeigneten radiologischen Untersuchungsmethode ist essenziell, um eine sichere Diagnose bzgl. der Dignitaet und damit das weitere Vorgehen bestimmen zu koennen. Damit wird eine unnoetige Verunsicherung des Patienten und des behandelnden Arztes vermieden, und invasive, eventuell mit Komplikationen assoziierte Biopsien sowie zeit- und kostenintensive Verlaufskontrollen koennen reduziert werden. Der folgende Artikel erlaeutert die haeufigsten und klinisch wichtigsten benignen fokalen Leberlaesionen und deren typisches und atypisches Erscheinen in den 3 haeufig verwendeten bildgebenden Verfahren Sonographie, Computertomographie und Magnetresonanztomographie. (orig.)

Baroud, S.; Bastati, N.; Prosch, H.; Ba-Ssalamah, A. [AKH, Medizinische Universitaet Wien, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria); Schima, W. [Krankenhaus Goettlicher Heiland, Wien, Abteilung fuer Radiologie und Bildgebende Diagnostik, Wien (Austria)

2011-08-15

393

CT scan findings in focal epilepsy  

International Nuclear Information System (INIS)

In 80 cases of focal epilepsy, excluding such cases as late onset after the age of 30 and traumatic or expansive lesions, the epileptogenic foci have been studied by comparing the CT findings with the seizure types and the EEG findings. The results were as follows: (1) Abnormal CT findings were observed in 36% of the patients. (2) These findings were classified into 4 large groups: localized cerebral atrophy, localized low density, localized high density with contrast enhancement and diffuse cerebral atrophy. (3) The incidence of CT abnormality was higher in the cases with continuous and localized EEG abnormality than in the cases with other types of EEG abnormality. In 48% of the cases, the location of the abnormal CT findings coincided with their EEG foci. (4) In the cases of temporal lobe epilepsy without abnormal CT images, the print-out data compared with the bilateral promised temporal regions, before and after contrast enhancement. The EMI-No. of the medial temporal focus increased more than that of the contralateral side in 3 cases out of 4 after contrast-media injection. (5) Moreover, for the purpose of comparing the CT findings on general seizures with those in focal seizures, we have studied 80 cases of general seizures. In the cases of the general seizures, abnormal CT findings were observed in only 16%. These abnormal findings were diffuse in 5 cases, localized in 6 cases, and combined in 3 cases. (author)

394

Focal CT abnormality and epileptogenic focus  

International Nuclear Information System (INIS)

In 31 patients with temporal lobe epilepsy, the precise site of epileptogenic focus was determined by means of a depth EEG recording as one of the presurgical evaluations. In 13 patients, a CT scan revealed focal lesions; 7 in the left temporal lobe and 6 in the right temporal lobe. In 5 of the 7 patients and in 5 of the 6 patients the epileptogenic foci were determined in the temporal lobe on the side of a CT lesion. However, in 2 of the patients with a CT lesion in the left temporal lobe, independent epileptogenic foci were found in both the temporal lobes, and in the other patient with a CT lesion in the right temporal lobe, they were found in the right frontal and left temporal lobes. Thus, the CT lesions agreed in lateralization and focality with the epileptogenic foci in 10 of the 13 patients (77%), but they disagreed in 3 (23%). A CT lesion disclosed in the temporal lobe does not necessarily indicate the side and/or site where the epileptogenic focus may be localized. Although exceptions may be made, spatial disagreement was exemplified between the CT lesion and epileptogenic focus. Therefore, extreme caution has to be taken on the side and/or site of the epileptogenic focus when functional surgical indication is to be made. (author)

395

The Piriform Cortex and Human Focal Epilepsy  

Science.gov (United States)

It is surprising that the piriform cortex, when compared to the hippocampus, has been given relatively little significance in human epilepsy. Like the hippocampus, it has a phylogenetically preserved three-layered cortex that is vulnerable to excitotoxic injury, has broad connections to both limbic and cortical areas, and is highly epileptogenic – being critical to the kindling process. The well-known phenomenon of early olfactory auras in temporal lobe epilepsy highlights its clinical relevance in human beings. Perhaps because it is anatomically indistinct and difficult to approach surgically, as it clasps the middle cerebral artery, it has, until now, been understandably neglected. In this review, we emphasize how its unique anatomical and functional properties, as primary olfactory cortex, predispose it to involvement in focal epilepsy. From recent convergent findings in human neuroimaging, clinical epileptology, and experimental animal models, we make the case that the piriform cortex is likely to play a facilitating and amplifying role in human focal epileptogenesis, and may influence progression to epileptic intractability.

Vaughan, David N.; Jackson, Graeme D.

2014-01-01

396

MRI characteristics of focal cortical dysplasia  

International Nuclear Information System (INIS)

Objective: To summarize the MRI characteristics of focal cortical dysplasia (FCD). Methods: Patients with FCD proved histopathologically underwent MR imaging and surgical resection for intractable epilepsy. MRI characteristics of FCD were summarized according to the Palmini classification. Results: There were 14 patients with type I FCD and 14 with type II FCD. In type I FCD patients, 8 patients had abnormal MRI appearances such as cortical-white matter junction blurring and focal cortical thickening, and the temporal lobe was the most frequently affected area (9/14). Hippocampal Sclerosis (HS) was seen in 6 type I FCD patients. The MRI abnormalities can be seen in 11 type II FCD patients, of which 7 cases with frontal lobe seizure. Only 2 cases of HS were foud in type II FCD. Cortical thickening, high signal of white matter on T2WI and FLAIR, high signal band in the white matter from the surface to the ventricle were the most common MRI characteristics of type II FCD. Conclusion: Two types of FCD have different MRI features which is helpful to improve the accuracy of presurgical planning and determine the prognosis of epilepsy surgery. (authors)

397

Fast & Furious focal-plane wavefront sensing  

CERN Document Server

We present two complementary algorithms suitable for using focal-plane measurements to control a wavefront corrector with an extremely high spatial resolution. The algorithms use linear approximations to iteratively minimize the aberrations seen by the focal-plane camera. The first algorithm, Fast & Furious (FF), uses a weak-aberration assumption and pupil symmetries to achieve fast wavefront reconstruction. The second algorithm, an extension to FF, can deal with an arbitrary pupil shape; it uses a Gerchberg-Saxton style error reduction to determine the pupil amplitudes. Simulations and experimental results are shown for a spatial light modulator controlling the wavefront with a resolution of 170 x 170 pixels. The algorithms increase the Strehl ratio from ~0.75 to 0.98-0.99, and the intensity of the scattered light is reduced throughout the whole recorded image of 320 x 320 pixels. The remaining wavefront rms error is estimated to be ~0.15 rad with FF and ~0.10 rad with FF-GS.

Korkiakoski, Visa; Doelman, Niek; Kenworthy, Matthew; Otten, Gilles; Verhaegen, Michel

2014-01-01

398

X-ray dark field imaging of human articular cartilage: Possible clinical application to orthopedic surgery  

Energy Technology Data Exchange (ETDEWEB)

Despite its convenience and non-invasiveness on daily clinical use, standard X-ray radiography cannot show articular cartilage. We developed a novel type of X-ray dark field imaging (DFI), which forms images only by a refracted beam with very low background illumination. We examined a disarticulated distal femur and a shoulder joint with surrounding soft tissue and skin, both excised from a human cadaver at the BL20B2 synchrotron beamline at SPring-8. The field was 90 mm wide and 90 mm high. Articular cartilage of the disarticulated distal femur was obvious on DFI, but not on standard X-ray images. Furthermore, DFI allowed visualization in situ of articular cartilage of the shoulder while covered with soft tissue and skin. The gross appearance of the articular cartilage on the dissected section of the proximal humerus was identical to the cartilage shown on the DFI image. These results suggested that DFI could provide a clinically accurate method of assessing articular cartilage. Hence, DFI would be a useful imaging tool for diagnosing joint disease such as osteoarthritis.

Kunisada, Toshiyuki [Department of Medical Materials for Musculoskeletal Reconstruction, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama 700-8558 (Japan); Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama 700-8558 (Japan)], E-mail: toshi-kunisada@umin.ac.jp; Shimao, Daisuke [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, Ibaraki 300-2394 (Japan); Sugiyama, Hiroshi [Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Ibaraki 305-0801 (Japan); Takeda, Ken; Ozaki, Toshifumi [Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama 700-8558 (Japan); Ando, Masami [Research Institute for Science and Technology, Tokyo University of Science, Chiba 278-8510 (Japan)

2008-12-15

399

Experimental study on radioisotope synovectomy with 153Sm-HA by intra-articular injection  

International Nuclear Information System (INIS)

Objective: To investigate safety and effects of intra-articular injection of 153Sm-citrate-hydroxyapatite (HA) on antigen-induced arthritis. Methods: Residual rates in knee joint and biological distribution of intra-articularly injected 153Sm-HA in normal joints and antigen-induced arthritis in rabbits were detected by SPECT, and the histopathologic changes of the joints were observed. Results: The intra-articular residual rates in normal joints and antigen-induced arthritis was 97.7% (3 d), 93.5% (6 d) and 98.4% (3 d), 95.1% (6 d), respectively. The total cumulative extra-articular leakage of 153Sm activity after intra-articular injection of 153Sm-HA in normal rabbits was 0.17%ID/g at 3 d and 0.31%ID/g at 6 d; in antigen-induced arthritis rabbits was 0.065%ID/g at 3 d and 0.0912%ID/g at 6 d, respectively. The histopathologic changes of treated knees showed that the inflammation was contained. Conclusions: Synovectomy with 153Sm-HA is effective in treatment of chronic arthritis and only insignificant accumulation of 153Sm activity can be detected in all non-target organs. This therapy is safe and deserves further study

400

Intra-articular bupivacaine as treatment for postoperative pain after arthroscopy of the wrist  

DEFF Research Database (Denmark)

Intra-articular injection of local anaesthetic is a confirmed method of treatment of postoperative pain, particularly after arthroscopy of the knee. The wrist however, has a limited capacity for intra-articular instillation of local anaesthetic, and the aim of this study was to investigate the effect of intra-articular bupivacaine on postoperative pain after arthroscopy of the wrist. We did a prospective, non-randomised study with two comparable, consecutive series of patients undergoing diagnostic/therapeutic wrist joint arthroscopy 20 of whom were given intra-articular 0.5% bupivacaine 5 ml at the end of the arthroscopic procedure and 20 of whom were not. Postoperative pain and use of analgesics (morphine, non-steroidal anti-inflammatory drugs (NSAID) and paracetamol) were recorded in all patients during the following five postoperative days using a visual analogue scale (VAS) and a pain diary. The bupivacaine group reported less pain and less use of analgesics in the first postoperative hours, but for the remaining five postoperative day's pain and the use of analgesics were similar in the two groups. We conclude that intra-articular injection of 0.5% bupivacaine 5 ml after wrist joint arthroscopy reduces pain and use of analgesics during the first postoperative hours, but has no effect during the following five days.

Hansen, Torben Bæk; Jakobsen, Inge Agergaard

2008-01-01