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ABSTRACT: Patients, physicians and third-party payers are becoming increasingly concerned with the economic burden resulting from advances in health care. Many economic health studies have focused on patients with sciatica and low back pain. An Economic Survey was conducted on lumbar discectomy patients who had been enrolled at least 12 months prior in a prospective randomized controlled clinical study of the adhesion control device ADCON-L. The survey measured patient satisfaction, return to work, additional medical treatment and medications after surgery. In addition, the duration of any re-operations from patients in the clinical study was analyzed. The results of the Economic Survey and re-operation time analysis show significant advantages for lumbar discectomy patients who received ADCON-L compared to control patients who did not. Patients who received ADCON-L not only had less scarring and less back pain than control patients but also were more satisfied with their surgeries and were able to return to work more often, as originally planned (p = 0.02). In addition, ADCON-L patients returned to their original jobs an average of 3.6 days sooner, changed jobs 50% less often, did not seek additional medical treatment as often, and took 20% less pain medication than did control patients (p = 0.01). In addition, patients receiving ADCON-L who required subsequent re-operation at the same lumbar space (e.g., reherniation) had a significantly shorter duration of secondary surgery (56.6 min vs. 130 min, p = 0.001) compared to patients who did not receive ADCON-L at the first surgery. Overall, ADCON-L patients demonstrated significant clinical and economic advantages over control patients. If all lumbar surgical patients in the US were to receive ADCON-L, annual savings to the health care system would exceed one half billion dollars.
Neurological Research 02/1999; 21 Suppl 1:S67-71. · 1.52 Impact Factor
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ABSTRACT: The 4-kd amyloid beta protein (A beta) deposited as amyloid in Alzheimer's disease (AD) is produced and released by normal proteolytic processing of the amyloid beta protein precursor (beta APP) and is readily detected in cerebrospinal fluid (CSF). Here, we present the levels of A beta in CSF from a total of 95 subjects, including 38 patients with AD, 14 with early-onset AD and 24 with late-onset AD, 25 normal control subjects, and 32 patients with other neurological diseases. The level of A beta decreased with normal aging, and there was a significant elevation in the level of A beta in the CSF of early-onset AD patients (4.14 +/- 1.37 pmol/ml, p < 0.01). Neither Mini-Mental State nor Functional Assessment Staging were correlated with the amount of A beta in the CSF. The A beta/secreted form of beta APP ratio was elevated, but the level of alpha 1-antichymotrypsin in the CSF did not correlate with the level of CSF A beta in early-onset AD patients. Thus, the level of A beta in the CSF is elevated in early-onset AD patients and is suggested to be correlated with the pathology in the brain that characterizes AD.
Annals of Neurology 01/1995; 36(6):903-11. · 11.09 Impact Factor
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ABSTRACT: The 4-kilodalton (39 to 43 amino acids) amyloid beta protein (beta AP), which is deposited as amyloid in the brains of patients with Alzheimer's diseases, is derived from a large protein, the amyloid beta protein precursor (beta APP). Human mononuclear leukemic (K562) cells expressing a beta AP-bearing, carboxyl-terminal beta APP derivative released significant amounts of a soluble 4-kilodalton beta APP derivative essentially identical to the beta AP deposited in Alzheimer's disease. Human neuroblastoma (M17) cells transfected with constructs expressing full-length beta APP and M17 cells expressing only endogenous beta APP also released soluble 4-kilodalton beta AP, and a similar, if not identical, fragment was readily detected in cerebrospinal fluid from individuals with Alzheimer's disease and normal individuals. Thus cells normally produce and release soluble 4-kilodalton beta AP that is essentially identical to the 4-kilodalton beta AP deposited as insoluble amyloid fibrils in Alzheimer's disease.
Science 11/1992; 258(5079):126-9. · 31.20 Impact Factor
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ABSTRACT: Because the mechanisms of A beta degradation in normal and Alzheimer's disease brain are poorly understood, we have examined whether various cortical cells are capable of processing this peptide. Rat microglia and astrocytes, as well as the human THP-1 monocyte cell line, degraded A beta 1-42 added to culture medium. In contrast, neither rat cortical neurons or meningeal fibroblasts effectively catabolized this peptide. When A beta fibrils were immobilized as plaque-like deposits on culture dishes, both microglia and THP-1 cells removed the peptide. Astrocytes were incapable of processing the A beta deposits, but these cells released glycosaminoglycase-sensitive molecules that inhibited the subsequent removal of A beta by microglia. This implied that astrocyte-derived proteoglycans associated with the amyloid peptide and slowed its degradation. The addition of purified proteoglycan to A beta that was in medium or focally deposited also resulted in significant inhibition of peptide removal by microglia. These data suggest that A beta can be catabolized by microglia and proteoglycans which co-localize with senile plaques may slow the degradation of A beta within these pathologic bodies.
Neurobiology of Aging 16(5):737-45. · 6.19 Impact Factor
