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C Palmer

Publications and source records attributed to C Palmer.

157 records · Page 9Linked to original sources
PubMedDate not supplied

31P NMR spectroscopy of perinatal hypoxic-ischemic brain damage: a model to evaluate neuroprotective drugs in immature rats.

Cerebral energy metabolism can be measured non-invasively in unanesthetized neonatal rats with 31P NMR spectroscopy. Using this technique, serial changes in high energy phosphates were determined from the right cerebral hemispheres of 7 day postnatal rat pups during a hypoxic-ischemic insult known to produce focal brain injury. During 3 h of hypoxia-ischemia the concentration of ATP dropped to 33 +/- 8% of prehypoxic (baseline) levels, phosphocreatine (PCr)/Pi decreased from 1.5 +/- 0.51 to 0.16 +/- 0.06, while pH decreased nominally by 0.2 units. After 2.5 h of recovery in air, ATP returned to 75 +/- 10% of baseline levels, PCr/Pi rose to 1.1 +/- 0.28, and pH returned to its normal value of 7.16 +/- 0.06. This model was used to test the efficacy of the adenosine deaminase inhibitor, 2-deoxycoformycin (DCF) as a potential neuroprotective drug. The data for the drug- and saline-treated populations were analyzed by integrating ATP and Pi/PCr levels over specific time intervals, expressing it relative to baseline levels, and modeling it with cubic splines. Pretreatment with 500 micrograms/kg DCF shows a small, but statistically significant, preservation of both ATP and phosphorylation potential during hypoxia and initial recovery. Brain water content (edema) at 42 h recovery was apparently associated with both mean ATP and mean Pi/PCr in the last 2 h of hypoxia-ischemia. When ATP fell below 70% of baseline, brain edema was evident at 42 h of recovery. This methodology is suitable for extension to human infants.

Adenosine Triphosphate↗
PubMedDate not supplied

A microwire technique for recording single neurons in unrestrained animals.

A technique is described in which bundles of 25 mu dia. insulated wires can be stereotaxically implanted for single unit recording in the brain. With this method extremely stable recordings can be obtained lasting many hours and sometimes days. The unit activity recorded with these electrodes has been found comparable with that recorded from rigid etched microelectrodes in conscious animals. The fine wire electrodes have also been found to be durable for at least a month when chronically implanted in cats. The electrode assembly is easy to construct and the electrodes are easily implanted in any region of the brain.

Animals↗
PubMedDate not supplied

Mouse p53 inhibits SV40 origin-dependent DNA replication.

p53 is a cellular phosphoprotein that is present at elevated concentrations in cells transformed by different agents. p53 complementary DNA expression-constructs immortalize primary cells in vitro and co-operate with an activated ras oncogene in malignant transformation. Several reports have implicated p53 in mammalian cell cycle control and specifically with events occurring at the G0-G1 boundary. p53 forms specific complexes with simian virus 40 (SV40) large-T antigen, and such complexes are found associated with both replicating and mature SV40 DNA in lytically infected cells. In an accompanying paper Gannon and Lane report that in in vitro plate-binding assays, mouse p53 can displace polymerase alpha from complex with T-antigen. We have examined the in vivo consequences of expressing wild-type and mutant p53 proteins from other species in SV40-transformed monkey cells. We report here that expression of mouse p53 results in a substantial and selective inhibition of SV40 origin-dependent DNA replication. In addition to any function in the G0-G1 transition, the data presented suggest that p53 may affect directly the initiation or maintenance of replicative DNA synthesis.

Animals↗
PubMedDate not supplied

Cost-effectiveness analysis of entacapone in Parkinson's disease: a Markov process analysis.

OBJECTIVE: The objective of this study was to examine the cost-effectiveness of a complementary treatment with entacapone versus usual care only in patients with Parkinson's disease. METHODS: The setting for this study was the Netherlands. A Markov process model was constructed to model the average quality-adjusted life years (QALYs) and the costs of both treatments. The model examined a period of 5 years in order to capture the influence of symptom improvement and disease progression. Data for the construction of the model were derived from published literature, including large, multicenter, randomized clinical trials in patients with end-of-dose motor fluctuations. Costs were obtained from published sources. RESULTS: The results of the baseline analysis showed that the use of entacapone as complementary therapy in Parkinson's disease slightly decreased the total average discounted costs from NLG 111,317 to NLG 110,038, while effectiveness increased from 2.42 to 2.56 QALYs (a 6% increase). In addition, entacapone substantially increased time without severe fluctuations by 0.63 years. Sensitivity analyses confirmed the robustness of these findings. CONCLUSION: The study shows that entacapone is a cost-effective treatment in patients with Parkinson's disease: entacapone yields higher effectiveness in terms of both effectiveness measures (time without severe fluctuations and QALYs), while costs remain quite similar to those for usual care. The additional drug costs for entacapone are offset by reductions in other costs.

Aged↗
PubMedDate not supplied

Health-care expenditures for tuberculosis in the United States.

BACKGROUND: The resurgence of tuberculosis (TB) and the increase in multidrug-resistant TB prompted this study, which estimates direct expenditures for TB treatment and public health activities in the United States. METHODS: This retrospective cost of illness study estimated 1991 direct expenditures for TB-related outpatient and inpatient diagnosis and treatment, screening, preventive therapy, contact investigations, surveillance, and outbreak investigations. Existing databases at the Centers for Disease Control and Prevention (Atlanta, Ga) and the Codman Research Group, Lebanon, NH, were supplemented by surveys of state and local TB programs and interviews of organizations that conduct large-scale screening. No estimates of indirect costs were made. RESULTS: The direct medical expenditures for TB in 1991 were estimated at $703.1 million. This cost includes $423.8 million for inpatient care, $182.3 million for outpatient care, $72.1 million for screening, $3.4 million for contact investigations, $17.9 for preventive therapy, and $3.6 million for surveillance and outbreak investigations. Sensitivity analyses yielded a range of expenditures between $515.7 million and $934.5 million. CONCLUSIONS: Treatment accounted for more than 86% of all TB-related expenditures; inpatient treatment accounted for 60% of the total. Prevention activities made up only 14% of all costs. Direct medical expenditures may be underestimated because of limitations in the database on hospital expenditures and health department cost-accounting systems and because of the lack of a national database on screening activities. Greater emphasis should be placed on outpatient treatment and prevention in high-risk populations, and improved cost-accounting systems should be developed in state and local health department TB control programs to facilitate economic evaluation and improve the allocation of health dollars.

Cost of Illness↗
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An update on OSHA.

Explore the source record for details and available documents.

Blood-Borne Pathogens↗