Electron Optics

Contains research objectives, summary of research on one research project, and reports on two research project.Joint Services Electronics Program (Contract DAAB07-74-C-0630

Accelerator irradiations of minerals - Implications for track formation mechanisms and for studies of lunar and meteoritic materials

Radiation effects of accelerated heavy ions in minerals characteristic of meteorite

802-6 The Cost-Effectiveness of Pravastatin in Secondary Prevention of Coronary Heart Disease

To determine the cost-effectiveness of pravastatin therapy in patients with coronary heart disease, a projected risk model was developed that used the results of the three-year, double blind, placebo controlled clinical trials: Pravastatin Limitation ofAtherosclerosis in the Coronary Arteries (PLAC I) and Pravastatin, Upids and Atherosclerosis in the Carotid Arteries (PLAC II). In addition to measuring atherosclerotic progression, the PLAC studies evaluated four outcome variables: coronary heart disease death, non-coronary heart disease death, fatal myocardial infarction, and non-fatal myocardial infarction in a patient population (mean age 60 years) with established coronary heart disease and moderate low-density-lipoprotein cholesterol levels, Pooled PLAC data analysis (n=559) revealed a statistically significant (p<0.05) difference in male non-fatal myocardial infarctions between the pravastatin and placebo groups. The projected risk model utilized Framingham data to project the risk of mortality 10 years post myocardial infarction. Markov Process was used to estimate the life-years saved and cost. All costs and benefits were discounted by 5%, Results are presented in the table below:Patient Risk ProfileCost per Life-Year SavedMale with CHD + 1Additional Risk Factor$19,082Male with CHD + 2 Additional Risk Factors$14,022Male with CHD + 3 Additional Risk Factors$10,630Based on this model, pravastatin monotherapy in secondary prevention of coronary heart disease has a cost-effectiveness ratio comparable to some of the widely accepted medical interventions such as breast cancer screening,$21,700, hydrochlorothiazide in the treatment of hypertension, $16,400, and pneumococcal vaccine,$12,000

Precision surveying using very long baseline interferometry

Radio interferometry measurements were used to measure the vector baselines between large microwave radio antennas. A 1.24 km baseline in Massachusetts between the 36 meter Haystack Observatory antenna and the 18 meter Westford antenna of Lincoln Laboratory was measured with 5 mm repeatability in 12 separate experiments. Preliminary results from measurements of the 3,928 km baseline between the Haystack antenna and the 40 meter antenna at the Owens Valley Radio Observatory in California are presented

Genes of cell-cell interactions, chemotherapy detoxification and apoptosis are induced during chemotherapy of acute myeloid leukemia

<p>Abstract</p> <p>Background</p> <p>The molecular changes <it>in vivo </it>in acute myeloid leukemia cells early after start of conventional genotoxic chemotherapy are incompletely understood, and it is not known if early molecular modulations reflect clinical response.</p> <p>Methods</p> <p>The gene expression was examined by whole genome 44 k oligo microarrays and 12 k cDNA microarrays in peripheral blood leukocytes collected from seven leukemia patients before treatment, 2–4 h and 18–24 h after start of chemotherapy and validated by real-time quantitative PCR. Statistically significantly upregulated genes were classified using gene ontology (GO) terms. Parallel samples were examined by flow cytometry for apoptosis by annexin V-binding and the expression of selected proteins were confirmed by immunoblotting.</p> <p>Results</p> <p>Significant differential modulation of 151 genes were found at 4 h after start of induction therapy with cytarabine and anthracycline, including significant overexpression of 31 genes associated with p53 regulation. Within 4 h of chemotherapy the BCL2/BAX and BCL2/PUMA ratio were attenuated in proapoptotic direction. FLT3 mutations indicated that non-responders (5/7 patients, 8 versus 49 months survival) are characterized by a unique gene response profile before and at 4 h. At 18–24 h after chemotherapy, the gene expression of p53 target genes was attenuated, while genes involved in chemoresistance, cytarabine detoxification, chemokine networks and T cell receptor were prominent. No signs of apoptosis were observed in the collected cells, suggesting the treated patients as a physiological source of pre-apoptotic cells.</p> <p>Conclusion</p> <p>Pre-apoptotic gene expression can be monitored within hours after start of chemotherapy in patients with acute myeloid leukemia, and may be useful in future determination of therapy responders. The low number of patients and the heterogeneity of acute myeloid leukemia limited the identification of gene expression predictive of therapy response. Therapy-induced gene expression reflects the complex biological processes involved in clinical cancer cell eradication and should be explored for future enhancement of therapy.</p

Models of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a major global health problem and is predicted to become the third most common cause of death by 2020. Apart from the important preventive steps of smoking cessation, there are no other specific treatments for COPD that are as effective in reversing the condition, and therefore there is a need to understand the pathophysiological mechanisms that could lead to new therapeutic strategies. The development of experimental models will help to dissect these mechanisms at the cellular and molecular level. COPD is a disease characterized by progressive airflow obstruction of the peripheral airways, associated with lung inflammation, emphysema and mucus hypersecretion. Different approaches to mimic COPD have been developed but are limited in comparison to models of allergic asthma. COPD models usually do not mimic the major features of human COPD and are commonly based on the induction of COPD-like lesions in the lungs and airways using noxious inhalants such as tobacco smoke, nitrogen dioxide, or sulfur dioxide. Depending on the duration and intensity of exposure, these noxious stimuli induce signs of chronic inflammation and airway remodelling. Emphysema can be achieved by combining such exposure with instillation of tissue-degrading enzymes. Other approaches are based on genetically-targeted mice which develop COPD-like lesions with emphysema, and such mice provide deep insights into pathophysiological mechanisms. Future approaches should aim to mimic irreversible airflow obstruction, associated with cough and sputum production, with the possibility of inducing exacerbations