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Biomedical subjects

B J Murphy

Publications and source records attributed to B J Murphy.

98 records · Page 6Linked to original sources
PubMedDate not supplied

The purified Ca2+ antagonist receptor from skeletal muscle: subunit structure, photoaffinity labeling and endogenous protein kinase activity.

Tritiated analogues of the Ca2+ channel blockers such as [3H] PN200-110, [3H] verapamil and [3H] diltiazem have been used to identify and isolate Ca2+ antagonist receptors. The Ca2+ antagonist binding sites were solubilized from skeletal muscle transverse tubules with the detergent CHAPS and purified by wheat germ lectin column chromatography and sucrose density gradient centrifugation. The isolated proteins retained their ability to bind the various classes of Ca2+ channel blockers. Polypeptides of 170, 150, 108, 56, and 32 kDa were found to be present in the purified receptor fraction when analysed by sodium dodecyl sulfate polyacrylamide gel electrophoresis under non-reducing conditions. The apparent molecular weight of the 170 kDa polypeptide changed to 145 kDa in the presence of reducing agents, as where the apparent molecular weight of the 150, 108, 56 and 32 kDa peptides remained unchanged. An endogenous protein-kinase present in the original membranes, co-purified with the receptor and stimulated the phosphorylation of the 150 and 56 kDa polypeptides in the isolated fraction.

Animals↗
PubMedDate not supplied

Giant cell tumor of the proximal tibia: MR and CT appearance.

The magnetic resonance (MR) appearance of four cases of giant cell tumor (GCT) of the proximal tibia are described and the MR grading of these tumors is compared with CT and conventional radiography. Magnetic resonance showed the lesions to be well defined with respect to adjacent marrow and cortical bone. Homogeneous intermediate signal intensity or low signal within the tumors was seen on T1-weighted images. T2-weighted images showed mixed signal intensity with small "bright patches" of increased signal intensity in all four cases. No fluid levels were identified. Magnetic resonance was superior to CT and plain radiography in radiologic grading of the tumors. Computed tomography was superior in determining if cortical invasion was present. Intraarticular tumor extension was more accurately detected by MR and arthrotomography than CT. An MR manifestation of GCT of the proximal tibia is described which may be a common appearance of this tumor by this modality. Magnetic resonance is the procedure of choice in the radiologic grading of GCT.

Adult↗
PubMedDate not supplied

Comparison of CT and MR imaging in musculoskeletal neoplasms.

Magnetic resonance (MR) and CT of 50 musculoskeletal neoplasms were compared to investigate the relative values of these modalities in the assessment and staging of musculoskeletal neoplasms and to determine how often they are complementary and when they are redundant. The material included 25 benign and 25 malignant neoplasms, of which 33 were skeletal and 17 were of soft tissue origin. Magnetic resonance was superior to CT with respect to all morphologic criteria except for cortical bone destruction, calcification, ossification, and the assessment of lytic and sclerotic changes in flat bones. Magnetic resonance was found to be complementary to CT in 48% of the cases (30% malignant, 18% benign). Use of both MR and CT was considered redundant in 52% of the cases (20% malignant, 32% benign). Magnetic resonance was found to be the modality of choice for all benign and malignant soft-tissue neoplasms. Both modalities are complementary and necessary for complete evaluation of malignant skeletal tumors. Benign skeletal tumors should be considered for evaluation by CT, MR, or both on an individual case basis.

Adolescent↗
PubMedDate not supplied

Evaluation of arthroscopic anterior cruciate ligament reconstruction using magnetic resonance imaging.

Thirty-two patients who had arthroscopic anterior cruciate ligament reconstruction using a bone-patellar tendon-bone autograft underwent subsequent magnetic resonance imaging of the knee. A total of 32 magnetic resonance imaging examinations were performed from 10 days to 39 months postoperatively. The anatomic plane of the autograft was determined by obtaining a coronal pilot scan of the graft fixation screws or screw and staple. T1-weighted, T2-weighted, proton density, and gradient-echo imaging sequences were then obtained in the anatomic plane, as well as T1-weighted coronal images. The autograft was defined on the basis of visualization of fiber continuity on T2-weighted images as follows: 1) intact; 2) having a partial tear; or 3) having a complete tear. These results were then correlated with clinical examination and, in 10 cases, subsequent arthroscopy. Magnetic resonance imaging correlated with clinical findings in 31 of 32 patients. In addition, of the 10 patients who underwent subsequent arthroscopy, magnetic resonance scanning correlated in all cases with arthroscopic findings. T2-weighted and, in some cases, proton density images were most useful in visualizing the autograft. T2-weighted magnetic resonance imaging in the anatomic plane of the anterior cruciate ligament autograft can be a useful diagnostic tool in the evaluation of patients with patellar tendon anterior cruciate ligament reconstructions when graft integrity is in question.

Adolescent↗
PubMedDate not supplied

Principles of good medical record documentation.

Although the world of medicine seems to be changing and progressing with each day, one thing that has not changed is the need for good documentation. The medical record of today does not only reflect your care of the patient, but has become a communication tool to a wide variety of players. Everyone seems to looking at your records, from colleagues to HMOs, and in the worst-case scenario, a plaintiff's attorney. This article will help show why good documentation is so important not only for good medical care, but if needed, as a defense tool if faced with a medical malpractice claim.

Documentation↗