Seton Medical Center

About: Seton Medical Center is a healthcare organization based out in Daly City, California, United States. It is known for research contribution in the topics: Angioplasty & Restenosis. The organization has 290 authors who have published 246 publications receiving 8282 citations. The organization is also known as: Mary's Help Hospital.

High Levels of Inflammatory Phospholipase A2 Activity in Lumbar Disc Herniations

Abstract: Inflammation of neural elements is frequently mentioned clinically in association with lumbar radiculopathy. Mechanical embarrassment of neural elements by definable structural abnormalities is inadequate as a sole explanation of nerve injury in this condition. The purpose of this study was to demonstrate whether an enzymatic marker for inflammation (phospholipase A2) could be identified in human disc samples removed at surgery for radiculopathy due to lumbar disc disease. Samples were assayed for phospholipase A2 activity. The level of activity in the disc samples was compared with values obtained from other human tissues using the same assay. Specific activity (percent hydrolysis radiolabelled substrate) ranged from 238 to 1,014.5 nmol/min/mg. Mean activity for the human disc material was 568.7 nmol/min/mg, compared with 0.006 nmol/min/mg for human PMN, and 12.1 nmol/min/mg for inflammatory human synovial effusion. The pH and cation-related activity were identical to those demonstrated for phospholipase A2 inflammatory conditions. Human lumbar disc phospholipase A2 activity is from 20- to 100,000-fold more active than any other phospholipase A2 that has been described. As the enzyme responsible for the liberation of arachidonic acid from cell membranes, phospholipase A2 is the rate-limiting step in the production of prostaglandins and leukotrienes. These data establish biochemical evidence of inflammation at the site of lumbar disc herniations.

Nonoperative treatment of herniated lumbar intervertebral disc with radiculopathy. An outcome study

Abstract: The functional outcome of patients with lumbar herniated nucleus pulposus without significant stenosis was analyzed in a retrospective cohort study. Inclusion criteria were as follows: 1) a chief complaint of leg pain, primarily; 2) a positive straight leg raising (SLR) at less than 60 degrees reproducing the leg pain; 3) a computed tomography (CT) scan demonstrating a herniated nucleus pulposus without significant stenosis by a radiologist's reading, which was also confirmed by the authors; 4) a positive electromyogram (EMG) demonstrating evidence of radiculopathy; and 5) response to a follow-up questionnaire. All patients had undergone an aggressive physical rehabilitation program consisting of back school and stabilization exercise training. Of a total of 347 consecutively identified patients, 64 patients with an average follow-up time of 31.1 months met the inclusion criteria and constituted the study population. They were sent questionnaires that inquired about activity level, pain level, work status, and further medical care. The patients with neurologic loss, extruded discs, and those seeking a second opinion regarding surgery were identified and subgrouped. Results for the total group included 90% good or excellent outcome with a 92% return to work rate. For the subgroups with extruded discs and second opinions, 87% and 83% had good or excellent outcomes, respectively, all (100%) of whom returned to work. Sick leave time for these subgroups was 2.9 months (+/- 1.4 months) and 3.4 months (+/- 1.7 months), respectively. These results compared favorably with previously published surgical studies. Four of six patients who required surgery were found to have stenosis at operation.(ABSTRACT TRUNCATED AT 250 WORDS)

The natural history of lumbar intervertebral disc extrusions treated nonoperatively

Abstract: The purpose of this study was to evaluate the natural history of morphologic changes within the lumbar spine in patients who sustained lumbar disc extrusions. All patients in this study were treated nonoperatively for radicular pain and neurologic loss. The following questions were addressed: 1) Does perithecal or perineural fibrosis result when extrusions are not removed surgically, and 2) Do disc extrusions spontaneously resolve, and, if so, how rapidly? The study population consisted of 11 patients with extrusions and radiculopathy. All patients were successfully treated nonoperatively. All had a primary complaint of leg pain and all had positive straight leg raising reproducing their leg pain at less than or equal to 60 degrees. Additionally, 87% had muscle weakness on a neurologic basis in a root level distribution corresponding to the site of disc pathology. Computed tomographic (CT) examinations were obtained on all patients at the inception of treatment. These studies were compared with follow-up MRI studies. The initial CT scans were evaluated for the following criteria: disc size and position, thecal sac effacement, nerve root enlargement or displacement, and evidence of central or intervertebral canal stenosis. In addition to the pathomorphology evaluated on the CT scans, follow-up MRI studies also evaluated disc hydration at the herniated and contiguous levels, and the presence of perithecal or perineural fibrosis. The following grading system was used to evaluate change in fragment size on the follow-up studies: Grade 1-0 to 50% decrease in size; Grade 2-50 to 75% decrease in size; Grade 3-75 to 100% decrease in size.(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous Coronary Intervention in the Current Era Compared With 1985–1986 The National Heart, Lung, and Blood Institute Registries

Abstract: Background—Although refinements have occurred in coronary angioplasty over the past decade, little is known about whether these changes have affected outcomes. Methods and Results—Baseline features and in-hospital and 1-year outcomes of 1559 consecutive patients in the 1997–1998 Dynamic Registry who were having first coronary intervention were compared with 2431 patients in the 1985–1986 National Heart, Lung, and Blood Institute Registry. Compared with patients in the 1985–1986 Registry, Dynamic Registry patients were older (mean age, 62 versus 58 years; P<0.001) and more often female (32.1% versus 25.5%; P<0.001). In the Dynamic Registry, procedures were more often performed for acute myocardial infarction (22.9% versus 9.9%; P<0.001) and treated lesions were more severe (84.5% versus 82.5% diameter reduction; P<0.001), thrombotic (22.1% versus 11.3%; P<0.001) or calcified (29.5% versus 10.8%; P<0.001). Stents were used in 70.5% of Dynamic Registry patients, whereas 1985–1986 patients received balloon an...