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D E Wilson

Publications and source records attributed to D E Wilson.

At least 37 records · Page 2Linked to original sources

Repeatability of ultrasound-predicted percentage of intramuscular fat in feedlot cattle.

We used data from 144 bulls, heifers, and steers to determine the repeatability of ultrasound-predicted percentage of intramuscular fat and to study the effect of repeated measurements on the standard error of prediction. Animals were scanned at an average age of 433 d by a certified technician. Individual bulls, heifers, and steers were scanned five to six times each with two Aloka 500-V machines, and the percentage of intramuscular fat was predicted from two regions of interest within an image. Variance components and repeatability values were computed for the overall data and by machine, region of interest, and sex. Animals were broadly divided into two groups based on mean ultrasound-predicted percentage of intramuscular fat. Variance components and repeatability values were then estimated within each group. The overall repeatability of ultrasound-predicted percentage of intramuscular fat was .63 +/- .03. Differences in the repeatability values between machines and between regions of interest were not different from zero (P > .05). Bulls showed a lower within-animal SD of .82% as compared to .97 and 1.02% for steers and heifers, respectively. However, steer ultrasound-predicted percentage of intramuscular fat measures were more repeatable (P < .05) than those of bulls and heifers. The difference in repeatability between bull and heifer measures was not important (P > .05). Animals with mean ultrasound-predicted percentage of intramuscular fat less than 4.79% showed less repeatable measures (P < .05) than those with means above 4.79%. The image variance contributed to nearly 70% of the total variance of observations within an animal. Standard error of animal mean measures showed a 50% reduction when the number of images per animal increased to four. Therefore, we concluded that increasing the number of images per animal plays a more significant role in reducing the standard error of prediction than taking multiple measurements within a single image.

Adipose Tissue↗

Has the well run dry? Priming the diversity pump in PhD programs.

America has always described itself as a melting pot of people and cultures. Perhaps it has become more of a "boiling pot" as assaults against affirmative action and charges of racism run rampant. Underrepresented minorities in the United States remain well below the national average with regard to education, employment, and health status. While today these minorities make up nearly 25% of the US population, historically they continue to be underrepresented in the medical and research professions. Some progress has been made during the last several decades, but it has stalled. And there is reason to believe that we are facing potentially rapid reversals of what has been painfully achieved. There is a significant pipeline problem in the production of minority doctorate recipients in America today. A review of a cohort of 17-year-old white and black students using a national longitudinal survey of the high school class of 1980 determined that 28% of white students graduated from college, compared with only 11% of black students--a 60% difference. Less than 1% of this original cohort of black students went on to earn science degrees. Doctoral programs now increasingly compete for the same small group of academically qualified minority students. The only long-term solution is to improve the educational opportunities starting from the early stages of the educational pipeline, beginning in elementary school. High school is too late. This process is complicated and will be costly. Pipeline initiatives will demand creativity, flexibility, and a commitment from all of us. We must increase the motivation and preparation of minority students regarding careers in science, engineering, and health care. We in academic health centers must play a key role in strengthening science education and in changing our behavior. We need to address the reasons why more than half of black students who enter college fail to graduate, why there is so little interest in science, and why minority students are not better prepared in science while they are in secondary school. And we need to address these issues now.

Education, Graduate↗

Bioequivalence assessment of a single 5 mg/day testosterone transdermal system versus two 2.5 mg/day systems in hypogonadal men.

A novel, nonscrotal, transdermal delivery system for testosterone therapy has been marketed for treatment of hypogonadal men. The usual dose of this system is two 2.5 mg/day systems applied daily. A new system has been developed that administers a dose of 5 mg/day using a single patch rather than two patches. A randomized, steady-state, four-period, replicate-design, open-label, crossover study was conducted to assess the bioequivalence of the two testosterone transdermal delivery systems in postpubertal, hypogonadal men: two 2.5 mg/day patches as the reference regimen (R) and one 5 mg/day patch as the test regimen (T). 21 men were enrolled, and 20 completed the study. Each subject was randomly assigned to one of four sequences (R1-R2-T1-T2, T1-T2-R1-R2, R1-T1-T2-R2, T1-R1-R2-T2), such that each subject received each regimen during two study sessions. Two subjects were inadvertently treated according to the sequence T1-R1-T2-R2. Patches were applied to the upper arm, thigh, and back in the evening on days 1, 2, and 3, respectively, of each study session. Serial blood samples were obtained for pharmacokinetic analysis of testosterone for 24 hours after patch application on day 3 of each study session. The two formulations would be considered bioequivalent if the 90% confidence intervals (CI) for the ratios of the adjusted geometric means for T:R for both area under the concentration--time curve from 0 to 24 hours (AUC0-24) and maximum concentration (Cmax) were completely contained in the interval (0.80, 1.25). Mean values for AUC0-24 and Cmax were similar for the two formulations. The T and R formulations were found to be bioequivalent based on both AUC0-24 (90% CI 0.96, 1.08) and Cmax (90% CI 0.92, 1.07). The median time to Cmax was also similar, indicating comparable rates of testosterone absorption for both formulations. Based on this analysis, the testosterone transdermal system 5 mg/day patch is bioequivalent to two of the 2.5 mg/day patches. Both systems were safe and well tolerated in hypogonadal men.

Administration, Cutaneous↗

Tapping the power of information: an orientation for academic medical centers.

In September 1994 the Association of American Medical Colleges' (AAMC's) Advisory Panel on the Mission and Organization of Medical Schools (APMOMS) established a working group to address both the long-term and the immediate implications of the expanding capacity of and need for information technology (IT) within academic medical centers (i.e., medical schools and teaching hospitals). Over a two-year period, group members assessed the utilization of IT through surveys of current practices and interactions with acknowledge leaders in the field. They also had discussions with deans and other institutional leaders. The group developed the consensus that proper use of currently available IT is crucial to virtually every aspect of academic medicine's clinical, educational, and research missions. Moreover, current IT technology will be further enhanced by the powerful new applications that are nearing deployment. All group members agreed that IT must become a core competency of academic and medical centers (AMCs), the profession, and individual physicians and scientists to ensure the survival of AMCs in the current highly competitive environments. The authors outline their arguments for the development of strong information systems within AMCs and present basic characteristics of systems that show promise for successful implementation. The y review some of the major institutional obstacles that have hindered the planing and implementation of IT. They conclude with a list of practical institution strategies for success in planning and implementing IT systems, and suggestions for how the AAMC can help members achieve success in these activities.

Academic Medical Centers↗

Fulfilling the social contract between medical schools and the public.

To gain a better understanding of the effects of medical schools related to transformations in medical practice, science, and public expectations, the Association of American Medical Colleges (AAMC) established the Advisory Panel on the Mission and Organization of Medical Schools (APMOMS) in 1994. Recognizing the privileges academic medicine enjoys as well as the power of and the strain on its special relationship with the American public, APMOMS formed the Working Group on Fulfilling the Social Contract. That group focused on the question: What are the roles and responsibilities involved in the social contract between medical schools and various interested communities and constituencies? This article reports the working group's findings. The group describes the historical and philosophical reasons supporting the concept of a social contract and asserts that medical schools have individual and collective social contracts with various subsets of the public, referred to as "stakeholders." Obligations derive implicitly from the generous public funding and other benefits medical school receive. Schools' primary obligation is to improve the nation's health. This obligation is carried out most directly by educating the next generation of physicians and biomedical scientists in a manner that instills appropriate professional attitudes, values, and skills. Group members identified 27 core stakeholders (e.g., government, patients, local residents, etc.) and outlined the expectations those stakeholders have of medical schools and the expectations medical schools have of those stakeholders. The group conducted a survey to test how leaders at medical schools responded to the notion of a social contract, to gather data on school leaders' perceptions of what groups they considered their schools' most important stakeholders, and to determine how likely it was that the schools' and the stakeholders expectations of each other were being met. Responses from 69 deans suggested that the survey provoked thinking about the broad issue of the social contract and stakeholders. Leaders on the same campuses disagreed about what groups were the most important stakeholders. Similarly, the responses revealed a lack of national consensus about the most important stakeholders, although certain groups were consistently included in the responses. The group concludes that medical school leaders should examine their assumptions and perspectives about their institutions' stakeholders and consider the interests of the stakeholders in activities such as strategic planning, policymaking, and program development.

Administrative Personnel↗

Acute dyslipoproteinemia induced by interleukin-2: lecithin:cholesteryl acyltransferase, lipoprotein lipase, and hepatic lipase deficiencies.

Recombinant human interleukin-2 (rIL-2) is used to treat refractory cancers. During such treatment, patients develop severe hypocholesterolemia along with striking alterations in the concentration and composition of the circulating lipoproteins. The present study was undertaken to gather information about the pathogenesis of these abnormalities. Patients were studied before-, during- and after a 5-day course of high dose i.v. rIL-2. Whole plasma cholesterol was markedly reduced by rIL-2 administration (52%; P < 0.001), whereas the triglyceride concentration did not change. Thus, the lipoproteins became triglyceride enriched (P = 0.004). Low density lipoprotein cholesterol, apolipoprotein B (apoB), high density lipoprotein cholesterol, and apoA-I concentrations all decreased. Esterified cholesterol levels were markedly reduced. Total plasma apoE increased markedly, and two kinds of abnormal particles appeared: 1) beta-migrating, very low density lipoproteins; and 2) discoidal, apoE- and phospholipid-containing particles with abnormal density and electrophoretic mobility. The activities of two lipoprotein triglyceride hydrolases, lipoprotein lipase and hepatic lipase, fell significantly during treatment and returned promptly to pretreatment levels after rIL-2 was discontinued. Lecithin:cholesteryl acyltransferase (LCAT) activity also decreased significantly (64%) during treatment, but in contrast to the lipases, remained low for at least 5 days after the last dose of rIL-2 (P < 0.001). High dose i.v. rIL-2 induces severe dyslipidemia with deficiencies of both postheparin lipases and acute LCAT deficiency. Most, if not all, of the lipoprotein changes observed are explained by the LCAT deficiency that follows IL-2-induced hepatocellular injury and cholestasis.

Apolipoprotein A-I↗

Caremap management for postoperative prostatectomy care at home: a comparative study.

OBJECTIVE: To evaluate early discharge from hospital with community-based care as an alternative to hospital-based care for patients who have undergone transurethral resection of the prostate (TURP). DESIGN: Prospective comparative study. SETTING: A major urban hospital and the urban community. PATIENTS: Of 198 patients who underwent TURP between Jan. 10, 1994 and Sept. 30, 1994, 81, discharged on postoperative day 1, received the caremap method of health care delivery at home. They were compared with 85 patients who were discharged on postoperative day 2 or 3 and received standard hospital-based care. MAIN OUTCOME MEASURES: Readmission to hospital, reuse of health care services, complications and patient satisfaction. RESULTS: Comparison of the 2 groups revealed no significant differences in readmissions to hospital, reutilization of health care services or complications. Following these initial results, the early discharge program was expanded to include all acute care hospitals and the surrounding community. CONCLUSIONS: Postoperative care for TURP can be delivered in the home. A critical success factor was the ability to provide quality care in the community without adverse effects.

Alberta↗

Whither academic health centers? A commentary.

Academic health centers (AHCs) currently face the greatest challenge of their entire existence. Managed care, increased competition for research funding, and inefficiency all contribute to the present vulnerability of AHCs in the cost competitiveness of today's health care marketplace. The increased reliance of medical schools on clinical income to subsidize undergraduate and graduate education and biomedical research now jeopardizes the success of their missions, since clinical income is declining. While AHCs must make significant changes to adapt to the new environment, left on their own in the marketplace, many will not survive. Additionally, the biomedical research advances and high technology medical care that we have come to expect in this country will also likely suffer. A national approach designed to preserve responsive AHCs is needed.

Academic Medical Centers↗

Caremap management in low-severity surgery: a comparative trial.

BACKGROUND: Caremap management refers to the management of defined patient groups using multidisciplinary clinical guidelines developed through literature review and expert opinion. STUDY DESIGN: Using a prospective preintervention and postintervention comparison model, this controlled study compared caremap management and traditional treatment in patients undergoing inguinal herniorrhaphy. Preintervention (n = 141) and postintervention (n = 110) groups were compared for hospital length of stay, resource consumption, and outcomes. RESULTS: Patients cared for by caremap management compared with traditional treatment showed a significant reduction in average length of stay (0.6 compared to 1.6 days, p < 0.01). Laboratory testing decreased by 60 percent in the caremap management group relative to traditional treatment (p < 0.01) and standardization of medication profiles was achieved. There were no significant differences in readmission rate, reutilization of health care services, or complications. Patients in the caremap management group indicated a preference for additional length of stay. CONCLUSIONS: Caremap management offers the potential for achieving effective patient care while using resources efficiently. Further evidence is required to demonstrate that caremap management can fulfill the promise of improving health status outcomes in varied types of patients.

Adult↗

Effect of the pSV2-neo plasmid on NIH 3T3 cell motion detected electrically.

Advantage was taken of DNA transfection techniques to investigate the effect of the pSV2-neo plasmid and its derivatives on recipient NIH 3T3 cell motion. Cell spreading and motion were followed by a newly developed electrical method to monitor cell morphology, referred to as electric cell-substrate impedance sensing. Using this method, we found that the eukaryotic-prokaryotic shuttle vector pSV2-neo had a strong effect on the recipient NIH 3T3 cell spreading and cell motion. However, two new neo plasmids, pSK-neo and pSP-neo, which were constructed by modifying the pSV2-neo plasmid, did not have a significant effect on the recipient cell activities. The results suggest that there may be some sequences in pSV2-neo which affect recipient cell behavior.

3T3 Cells↗

Diabetes increases hepatic hydroxymethyl glutaryl coenzyme A reductase protein and mRNA levels in the small intestine.

Previous studies have shown that both cholesterol synthesis and the activity of hepatic hydroxymethyl glutaryl coenzyme A (HMG CoA) reductase, the rate-limiting enzyme in cholesterol synthesis, are increased in the small intestine of a wide variety of different animal models of diabetes. In the present study, we demonstrate that the mass of HMG CoA reductase protein is increased in the small intestine of both streptozocin-induced diabetic rats (2.5-fold) and streptozocin/alloxan-induced diabetic dogs (2.4-fold). These increases in HMG CoA reductase protein mass are of a magnitude similar to the previously observed increases in either HMG CoA reductase activity and/or cholesterol synthesis in the small intestine of diabetic animals. Furthermore, mRNA levels for HMG CoA reductase in the small intestine of diabetic rats and diabetic dogs are increased 2.1- and 1.7-fold, respectively. These results suggest that the increase in HMG CoA reductase protein levels in the small intestine of diabetic animals is due to an increase in mRNA levels. In contrast, mRNA levels for HMG CoA reductase in the liver of diabetic rats are not increased. Additionally, mRNA levels for the low-density lipoprotein (LDL) receptor are also increased in the small intestine of diabetic animals (rats, 43%; dogs, 59%). The increase in small-intestinal cholesterol synthesis has the potential for adversely affecting lipoprotein metabolism and increasing the risk of atherosclerosis in diabetes.

Animals↗

Proximate, caloric, nitrogen and mineral composition of bodies of some tropical bats.

Proximate (live mass, water, lipid, ash, non-fat organic), caloric, nitrogen, and mineral (sodium, potassium, calcium, magnesium, and iron) concentrations and total body content of individuals of 24 species of Neotropical and Paleotropical bats were determined. Mass-related, concentration patterns were found for all measured variables, except iron. Concentrations increase with size for nitrogen, calcium, and magnesium but are concave, opening upward, for sodium and potassium. These last two elements reach minimal concentrations in bats weighing about 22 and 28 g dry mass, respectively. Total body content of nitrogen and minerals was compared with amounts in similar-sized birds and tetrapodal mammals.

Adipose Tissue↗

Molecular screening of the lipoprotein lipase gene in hypertriglyceridemic members of familial noninsulin-dependent diabetes mellitus families.

Hypertriglyceridemia is common among individuals with noninsulin-dependent diabetes mellitus (NIDDM), and heterozygous lipoprotein lipase (LPL) mutations may result in the syndrome of familial hypertriglyceridemia and low levels of high density lipoprotein (HDL) cholesterol. To test the hypothesis that heterozygous LPL mutations predispose to the hypertriglyceridemia and low HDL cholesterol levels observed among members of familial NIDDM families, we examined 36 members and 3 unrelated spouses selected from members of 20 pedigrees for triglyceride levels exceeding the age- and sex-specific 95th percentile. Eighteen pedigree members and 2 spouses were diabetic. LPL exons 1-9 were screened by single strand conformation polymorphism analysis. Six different variants were detected in exons 2, 3, 4, 8, and 9, including 4 (exons 3, 4, and 8) silent nucleotide substitutions. A common nonsense mutation (exon 9; Ser-->Ter) was present in 2 pedigrees, and a missense mutation (exon 2; Asp-->Asn) was also present in members of 2 pedigrees. Analysis of members of these families suggested an association of the exon 2 variant with hypertriglyceridemia, although this trend was no longer significant when individuals with diabetes were excluded from the analysis. The variant enzyme was not present among 83 random control individuals, and when expressed in COS-1 cells, it was similar to the wild type with respect to specific activity, heparin binding, and heat stability. Our data suggest that coding region mutations of the LPL gene cannot account for the elevated triglyceride and low HDL levels noted in diabetic individuals and their relatives in most NIDDM pedigrees, but the exon 2 Asn variant may contribute to the hypertriglyceridemia in some families.

Adult↗