Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: HUMANGGP:010955 (mda-7)
 464 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Reconstruction of the anterior crucial ligament can be performed by using an autogenous transplant from the patellar ligament. Employing postoperative MR investigation, reaction of the non-vascularised tendon was studied. In 16 patients 20 knees were investigated by applying a 1.5 tesla magnet with T1-weighted (TR 500 ms, TE 15 ms) and a T2*-weighted (FISP 3D: TR 30 ms, TE 10 ms, flip angle 40 degrees). Postoperative MR follow-up showed an increase in signal intensity and diameter in T1-weighted images. This represents revascularisation of the transplant.
Rofo 1990 Dec
PMID:[A NMR tomographic follow-up assessment of the replacement plastic repair of the anterior cruciate ligament with an autologous ligamentum patellae transplant]. 217 29

This study evaluates magnetic resonance imaging (MRI) in the detection of surgically created articular defects in bovine knees. A total of 26 articular defects was created in 2 fresh cadaveric cows' knees. The defects created include chondromalacic grade 2 defects, chondral and osteochondral defects from 3 to 15 mm in diameter. The knee joints were repaired in a normal saline bath to exclude air in the joint prior to MR scanning. T1 weighted spin echo (SE) images and 3D gradient echo (FISP 40 degrees 3D) images were obtained. The T1 weighted SE imaging technique detected 15 defects (57.7%) compared with FISP 3D imaging technique detection of 17 defects (65.4%). The two techniques combined enable 21 of 26 defects (80.8%) to be detected. The imaging techniques used in this study were not able to detect chondromalacic defects less than 10 mm in diameter, nor chondral defects less than 5 mm in diameter. However, small osteochondral defects of 3 mm in diameter are detectable provided the depth of the defect is not less than 10 mm. The FISP 3D imaging technique alone is more sensitive in detecting chondral defects. Both imaging techniques have similarly high sensitivities in detecting osteochondral defects. The imaging time for combined T1 weighted SE and FISP 3D sequence is short (16.5 mm) and this combined technique may be useful for MR scanning of knee joints suspected to have articular defects.
Aust N Z J Surg 1990 Dec
PMID:Detection of articular defects using magnetic resonance imaging: an experimental study. 226 16

Forty-one patients with histologically proven hepatic lesions (6 cysts, 6 hemangiomas, 8 hepatomas, 19 metastases and 2 negative cases) were studied with Magnetic Resonance (MR) imaging at 1.5 T, and with US and CT. This prospective study was aimed at evaluating: the comparative accuracy of MR, US and CT; the sensitivity and specificity of spin-echo (SE) vs FISP pulse sequences; the efficacy of T1 and T2 relaxation time values in differentiating hemangiomas from hepatomas and metastases. MR diagnostic accuracy was 94.7% vs 89.4% of CT and 84.2% of US. FISP sequences provided 60% sensitivity and 66% specificity. T2 relaxation time values were statistically significant (p less than 0.05) in differentiating hemangiomas (T2 range: 80.9-218.9 ms) from hepatomas (T2 range: 59.4-83.2 ms). The differences in mean T2 values between hemangiomas and metastases (T2 range 54.3-177.3 ms) were not statistically significant (p greater than 0.25).
Radiol Med 1989 Dec
PMID:[Magnetic resonance in hepatic lesions. Experience with a 1.5-T magnetic field]. 256 May 78

Magnetic resonance imaging (MRI) is being applied successfully to the study of the musculoskeletal system with notable recent advances, including the use of three-dimensional imaging techniques. The authors introduce three-dimensional MRI as a technique for examining proximal femoral anatomy and suggest its use as an improvement on current methods for prosthetic hip design. The proximal femurs of 14 cadavers were scanned using a three-dimensional FISP technique and the images were subsequently manipulated on a three-dimensional MRI image-processing workstation to produce rotated surface reconstructions and multiplanar reformatted images. The surface rotations showed that the marrow cavity contours closely follow the contours of the external cortex. Axially reformatted images allowed relative area measurements of the marrow cavity, quantifying the variability between subjects.
J Arthroplasty 1989 Dec
PMID:Anatomy of the proximal femur as seen with three-dimensional magnetic resonance imaging. 262 69

Two-dimensional (2D) spin-echo (SE) sequences and three-dimensional (3D) FISP (fast imaging with steady precession) sequences of the knee with the same section thickness and field of view were directly compared in 54 patients, 17 of whom underwent subsequent follow-up (15 arthroscopic and two arthrographic examinations). In those patients with follow-up, each sequence demonstrated 100% sensitivity, 80% specificity, and 94% accuracy for evaluation of the medial meniscus and 100% sensitivity, 100% specificity, and 100% accuracy for evaluation of the lateral meniscus. SE imaging demonstrated 100% sensitivity, 100% specificity, and 100% accuracy for evaluation of the anterior cruciate ligament, while 100% sensitivity, 82% specificity, and 88% accuracy were achieved with FISP imaging. In the 37 patients without follow-up, only two discrepancies were found between the 2D SE and the 3D FISP images for meniscal evaluation. Three discrepancies were found in the evaluation of the anterior cruciate ligament, two of which were likely false-positive 3D FISP results. We conclude that 2D SE and 3D FISP imaging provide comparable data for meniscal evaluation. FISP images are slightly less accurate than SE images of comparable resolution for the evaluation of the anterior cruciate ligament.
Radiology 1989 Dec
PMID:MR imaging of the knee: comparison of three-dimensional FISP and two-dimensional spin-echo pulse sequences. 281 79

Cultured human melanoma cells lose proliferative capacity and terminally differentiate after treatment with the combination of recombinant human fibroblast interferon (IFN-beta) and mezerein (MEZ). Subtraction hybridization of cDNA libraries prepared from actively proliferating human H0-1 melanoma cells from cDNA libraries produced from H0-1 cells treated with IFN-beta + MEZ identifies a novel melanoma differentiation-associated (mda) cDNA, mda-7, that displays elevated expression in differentiation inducer-treated H0-1 cells. mda-7 encodes a novel protein of 206 amino acids with a predicted size of 23.8 kDa. The level of mda-7 mRNA is elevated in actively proliferating normal human melanocytes versus primary and metastatic human melanomas. In the Matrigel-assisted melanoma progression model, mda-7 expression decreases in early vertical growth phase primary human melanoma cells selected for autonomous or enhanced tumor formation in nude mice. Treatment of human melanomas with IFN-beta + MEZ, and to a lesser extent with MEZ, results in growth suppression and induced or enhanced mda-7 expression. Immunoprecipitation analyses using peptide-derived rabbit polyclonal antibodies detect increases in mda-7 protein, and a higher molecular weight protein of approximately 90 to 100 kDa, in MEZ and IFN-beta + MEZ treated H0-1 cells. mda-7 is a highly conserved gene with an homologous sequence in the genome of yeast. Transfection of mda-7 expression constructs into H0-1 and C8161 human melanoma cells reduces growth and inhibits colony formation. These results confirm that mda-7 has antiproliferative properties in human melanoma cells and in this context may contribute to terminal cell differentiation. The mda-7 gene may also function as a negative regulator of melanoma progression.
Oncogene 1995 Dec 21
PMID:Subtraction hybridization identifies a novel melanoma differentiation associated gene, mda-7, modulated during human melanoma differentiation, growth and progression. 854 4

The aim of this article is the systematic treatment of fast and ultrafast magnetic resonance imaging (MRI) techniques. Based on the basic principles of signal generation and spatial encoding with magnetic field gradients the differences and important similarities of pulse sequences will be explained. We suggest to replace the conventional grouping of pulse sequences in gradient and spin-echo sequences through single and multi-echo sequences, since the latter is more precise and helpful. We illustrate how single-echo sequences such as "spin-echo", FLASH, FISP, PSIF, CISS and DESS can be derived from a single gradient echo and how multi-echo sequences such as turbo spin-echo RARE, HASTE and GRASE are based on echo-planar imaging. The different properties, advantages and disadvantages of the various sequences will be discussed and frequently used acronyms will be explained.
Radiologe 1995 Dec
PMID:[Fast and ultra-fast magnetic resonance tomography. Basic principles, pulse sequences and special properties]. 858 31

The authors report on their clinical experience with Magnetic Resonance angiography (MRA) pitfalls. January, 1989, to February, 1995, six hundred MRA examinations were performed in different vascular districts, with a 1.5-T superconductive magnet, the time-of-flight (TOF) technique and 2D and 3D acquisitions. Intracranial arteries, epiaortic vessels and renal arteries were studied with FISP 3D sequences; intracranial veins, thoracic vessels, vena cava and pelvic vessels were studied with FISP 2D sequences. Pitfalls were observed in 56 of 600 MRA exams (9.3%). Of 56 pitfalls, 26 (46.4%) were in epiaortic vessels, 15 (26.7%) in intracranial vessels, 6 (10.7%) in renal arteries, 6 (10.7%) in thoracic vessels, 1 (1.7%) in the inferior vena cava and 2 (3.5%) in iliac vessels. Stenoses were overestimated in 21 patients and underestimated in three; 16 patients were misdiagnosed and 16 were false positives. As for cerebral vascular lesions, 5 aneurysms and 7 transverse sinus thromboses were false positives, while 3 lesions were misdiagnosed as venous angiomas. As for 26 MRA exams of thoracic vessels, stenoses were overestimated in 16 patients and underestimated in 10 patients with subclavian steal syndrome, where the left vertebral artery was misinterpreted as occluded. In 6 MRA exams of thoracic vessels, 1 patient was misdiagnosed as having an aneurysm and 5 patients were misdiagnosed as having lung cancer infiltrating aorta and superior vena cava. As for renal vessels, 2 normal renal arteries were misdiagnosed as false positives and 4 stenoses were overestimated. In the inferior vena cava, a partial agenesis was misinterpreted as thrombosis. In 2 MRA exams of iliac vessels, a stenosis and a thrombosis were misinterpreted as false positives. Our experience suggests that MRA pitfalls are caused by the incorrect use of the various techniques. The pitfalls we observed can be classified as caused by three types of artifacts: saturation, turbulence and paramagnetic substance artifacts.
Radiol Med 1995 Dec
PMID:[Diagnostic pitfalls in magnetic resonance angiography]. 868 55

Imaging with three-dimensional (3D) sequences is a frequently used magnetic resonance (MR) technique in the assessment of ear, nose and throat (ENT) tumours near the skull base. Few reports on the contrast behaviour of 3D magnetization prepared rapid gradient echo (MP-RAGE) sequences and their application in ENT tumours exist in the published literature. This paper discusses whether 3D MP-RAGE is an alternative to conventional 3D gradient echo (3D GE) sequences for the diagnostic evaluation of the visceral cranum. Measurements were performed with a Magnetom SP 63 MR system (Siemens) at 1.5 T. 10 healthy volunteers were examined using 3D FLASH sequences with varied flip angles (90 degrees, 70 degrees, 40 degrees, 20 degrees, 10 degrees) and using 3D MP-RAGE to optimize the signal-to-noise ratio (SNR) of muscle, fat and gland tissue. After this optimization 25 patients with ENT tumours near the skull base were examined with 3D FLASH 40 degrees, 3D MP-RAGE 10 degrees (both before and after application of contrast medium) and with 3D FISP 70 degrees (without contrast medium). SNR and contrast-to-noise ratio (CNR) of tumour, inflammatory disease, brain (white and grey matter), compact bone, fat and muscle were calculated. The advantages of 3D MP-RAGE over 3D FLASH 40 degrees include decreased imaging time with decreased motion artifacts and a relatively high contrast between tumour and surrounding tissues. The tissue contrast yielded by the T1/T2* weighted 3D gradient echo sequence FISP with a flip angle of 70 degrees was not as good as that yielded by 3D MP-RAGE with and without contrast together. In conclusion a combination of contrast enhanced and unenhanced 3D MP-RAGE sequences is the technique of choice for the examination of ENT tumours near the base of the skull.
Br J Radiol 1995 Dec
PMID:Three-dimensional MP-RAGE--an alternative to conventional three-dimensional FLASH sequences for the diagnosis of viscerocranial tumours? 877 92

The purpose of this study was to investigate capabilities of Magnetic Resonance Angiography (MRA) in delineating neurovascular compression which has emerged as the most frequent etiology in cases of Hemi-Facial Spasm and Trigeminal Neuralgia. MR investigations were carried out at 1.5 t unit (Magnetom Vision, Siemens). The examination consisted of 3D time-of-flight MRA (3d TOF) protocol, with a FISP sequence (Fast Imaging Steady Precession) and magnetization transfer. Imaging parameters were; TR 39 ms, TE 7 ms; MX 256-512; FOV 210-210 mm. Time acquisition is 10 mm 30 s. The axially acquired angiographic slices were reformatted with a multiplanar reconstruction program (MPR) along and across the plane of facial and trigeminal nerves. Then millimetric raw data images were postprocessed with a maximum intensity projection (MIP) technique. 58 patients presented either with hemifacial spasm (36 cases, 16 women, 20 men, mean age: 58.5 y) or trigeminal neuralgia (22 cases, 13 women, 8 men, mean age: 51 y) were compared with 17 patients (9 women, 8 men, mean age: 57.5 y) as references. MRA with MIP and MPR techniques reliably demonstrates neurovascular compression at the root entry zone (REZ), and allows recognition of the implicated vascular loop in 34 the cases of hemifacial spasm investigated. Raw data were post-processed in an axially oblique plane parallel to the acoustico-facial bundle and secondarily reconstructed in coronally obliques views. These reconstructed images clearly delineate the cross-compression of the emerging facial nerve. The neurovascular conflict was related to an arterial loop from the postero-inferior cerebellar artery (PICA, 21 cases, 61%) and the antero-inferior cerebellar artery (AICA, 8 cases, 23%). Vertebral artery is implicated in conflicts in 5 cases. In 2 cases MRA exploration was negative. In HFS group distance between Vth nerve emergency and neuro vascular contact was measured and compared with control group; there is a significative difference (p < 0.01). In case of trigeminal neuralgia, MRA demonstrates neurovascular compression at the root entry zone of the Vth nerve of 16 patients. In theses cases, oblique and coronally reconstructed images are crucial in demonstrating neurovascular contacts. The vessel implicated in conflict is always the superior cerebellar artery (SCA). A supero-medial loop of the superior cerebellar artery was depicted in these 16 cases. Although 3 patients had negative MRA and MR studies, a case of compression of the origin of the Vth nerve by a enlarged draining vein in a case of brainstem arterio-venous malformation, a petrous apex meningioma was incidentally discovered and thoroughly investigated with gadolinium T1 weighted sequences and 1 demyelinating plaques located along the intraaxial course of the Vth nerve were noticed. In control group on 34 explanations only there are only 4 contacts between Vth nerve and SCA. MRA with a 3D-TOF FISP sequence allows recognition of neurovascular conflicts in case of hemifacial spasm and trigeminal neuralgia while MIP helps to characterize the implicated vessel. Sources images need to be carefully assessed in order to depict unsuspected pathology.
J Neuroradiol 1996 Dec
PMID:[The contribution of "time-of-flight" MRI-angiography in the study of neurovascular interactions (hemifacial spasm and trigeminal neuralgia)]. 909 7


1 2 3 4 Next >>