2,438 research outputs found
Social/health maintenance organization and fee-for-service health outcomes over time.
Evaluating the performance of long-term care (LTC) demonstrations requires longitudinal assessment of multiple outcomes where selective mortality and disenrollment, if not accounted for, can give the appearance of reduced (or enhanced) efficacy. We assessed outcomes in social/health maintenance organizations (S/HMOs) and Medicare fee-for-service (FFS) care using a multivariate model to estimate active life expectancy (ALE). S/HMO enrollees and samples of FFS clients in four sites were analyzed and outcome differences assessed for a 3-year period. Results provide insights into S/HMO performance under different conditions and, more generally, into evaluating LTC demonstrations without randomized client and control groups
Endogenous retinoids in rat epididymal tissue and rat and human spermatozoa
Recent work has demonstrated high levels of retinoid binding proteins in rat epididymis, and a lumenal retinoic acid binding protein has been purified. These findings suggested that vitamin A may be involved in spermatozoal maturation in the epididymis. We further addressed this question by quantifying retinol, retinyl esters, and retinoic acid isomers from perfused epididymal tissue, from rat testicular and epididymal spermatozoa, and from human ejaculate sperm. HPLC showed vitamin A levels to be higher in caput than in corpus or cauda tissue. Retinoic acid and 9-cis-retinoic acid were found to be graded from lowest levels in caput to highest in cauda. Spermatozoa from caput epididymidis and enriched testicular spermatozoa were found to have higher levels of vitamin A than did spermatozoa from corpus or cauda epididymidis. Spermatozoal retinyl esters had acyl substituents similar to those seen in whole epididymis, and diminished in quantity in sperm from distal segments. Human ejaculate sperm were found to retain high levels of retinyl palmitate and stearate. Retinol and retinoic acid were only marginally detectable in human sperm. Retention of retinoids in mature spermatozoa suggests roles for vitamin A in spermatozoal reproductive physiology beyond the epididymal stage
Insights from the x-ray crystal structure of coral 8R-lipoxygenase: Calcium activation via a C2-like domain and a structural basis of product chirality
Lipoxygenases (LOXs) catalyze the regio- and stereospecific dioxygenation of polyunsaturated membrane-embedded fatty acids. We report here the 3.2 Å resolution structure of 8R-LOX from the Caribbean sea whip coral Plexaura homomalla, a LOX isozyme with calcium dependence and the uncommon R chiral stereospecificity. Structural and spectroscopic analyses demonstrated calcium binding in a C2-like membrane-binding domain, illuminating the function of similar amino acids in calcium-activated mammalian 5-LOX, the key enzyme in the pathway to the pro-inflammatory leukotrienes. Mutation of Ca2+- ligating amino acids in 8R-LOX resulted not only in a diminished capacity to bind membranes, as monitored by fluorescence resonance energy transfer, but also in an associated loss of Ca2+-regulated enzyme activity. Moreover, a structural basis for R chiral specificity is also revealed; creation of a small oxygen pocket next to Gly428 (Ala in all S-LOX isozymes) promoted C-8 oxygenation with R chirality on the activated fatty acid substrate. © 2005 by The American Society for Biochemistry and Molecular Biology, Inc
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Groundwater Monitoring at the 1100-EM-1 Operable Unit
The purpose of this report is to provide a comprehensive summary of the distribution and trends of volatile organic compound concentrations near USDOE’s Horn Rapids Landfill (HRL). This report focuses mainly on the TCE plume monitored in the top of the unconfined aquifer near the HRL, but also addresses potential breakdown products of TCE. TCE concentrations in deep portions of the unconfined aquifer and the underlying confined aquifer are discussed to show the vertical extent of contamination. This report incorporates TCE data from offsite wells at the AREVA facility south of the Hanford Site. Discussion of TCE in groundwater in the 300 Area is included to differentiate between contaminant plumes and their sources in the 300 Area and near the HRL. Chromium monitoring results from a specific well downgradient of the 1171 Building is also included
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300 Area VOC Program Slug Test Characterization Results for Selected Test/Depth Intervals for Wells 399-2-5, 399-3-22, and 399-4-14
Multiple, stress-level slug tests were performed at selected test/depth intervals within wells 399-2-5, 399-3-22, and 399-4-14 as part of the 300 Area volatile organic compound characterization program at the Hanford Site in Washington State. The temporary test screen lengths were characterized as the boreholes were advanced to their final drill depths and before their completion as monitor-well facilities. Following well completion, slug tests were performed in the final, completed well-screen sections. The objectives of the slug tests were to provide the vertical distribution of hydraulic conductivity with depth at these locations and to support selection of the final well screen-depth interval for each of these monitor-well facilities
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Slug Test Characterization Results for Multi-Test/Depth Intervals Conducted During the Drilling of CERCLA Operable Unit OU ZP-1 Wells 299-W10-33 and 299-W11-48
Slug-test results obtained from single and multiple, stress-level slug tests conducted during drilling and borehole advancement provide detailed hydraulic conductivity information at two Hanford Site Operable Unit (OU) ZP-1 test well locations. The individual test/depth intervals were generally sited to provide hydraulic-property information within the upper ~10 m of the unconfined aquifer (i.e., Ringold Formation, Unit 5). These characterization results complement previous and ongoing drill-and-test characterization programs at surrounding 200-West and -East Area locations (see Figure S.1)
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BP-5 Remedial Investigation Slug-Test Characterization Results for Well 699-52-55A
Pacific Northwest National Laboratory conducted slug-test characterization at the final, completed BP-5 Remedial Investigation well 699-52-55A near the 200-East Area at the Hanford Site on April 22, 2008. The slug-test characterization was in support of the BP-5 Remedial Investigation. The portion of the unconfined aquifer tested is composed of sediments of the lower Ringold Formation and the underlying Elephant Mountain basalt flowtop. The basalt flowtop unit was included as part of the effective test-interval length for the slug-test analysis because the flowtop unit is hydraulically communicative with the unconfined aquifer. Estimates of hydraulic conductivity for the effective test-interval length represent composite values for the lower Ringold Formation and the underlying Elephant Mountain basalt flow top
The Relationship of Serum Transferrin and Iron to the Rapid Formation of Germ Tubes by Candida Albicans**From the Department of Medicine, Division of Dermatology, University of California, The Center for the Health Sciences, Los Angeles 24, California and Medical Service, Veterans Administration Center, General Medical and Surgical Hospital, Los Angeles 25, California.
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