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Biomedical subjects

C E Allen

Publications and source records attributed to C E Allen.

At least 19 recordsLinked to original sources

Effects of compensatory growth on some body component weights and on carcass and noncarcass composition of growing lambs.

A trial was conducted in 1983 and repeated in 1984 to measure effects of restricted feed intake and realimentation on weights of organs and on carcass and noncarcass composition. A total of one hundred six weaned lambs from two breeds (Timahdit and D'man) and a breed cross (Ile de France x D'man) were used in both years. Lambs were allotted to one of six feed intake regimens: HH (ad libitum access to feed from 21 to 30 kg); HM (ad libitum access to feed from 21 to 26 kg then 70% ad libitum to 30 kg); MH (70% ad libitum from 21 to 26 kg then ad libitum to 30 kg); MM (70% ad libitum from 21 to 30 kg); LH (restricted to lose weight from 21 to 17 kg then ad libitum to 30 kg); and LM (restricted to lose weight from 21 to 17 kg then 70% ad libitum to 30 kg). Weights of visceral organs and mesenteric and kidney fat showed dramatic responses to alteration of feed allowances. After recovery from 20% live weight loss, weight of liver equaled or exceeded that of both the ad libitum and 70% refed lambs. Mesenteric and kidney fat did not. Refeeding was accompanied by an increase in water (P less than .05) and a decrease in fat (P less than .01) of both carcass and noncarcass components. These results indicate that weight loss of lambs incurred during feed shortage was largely in internal organ weights, and that these lambs can recover these losses during realimentation and undergo compensatory growth with better feed efficiency and lean carcasses.

Adipose Tissue

Effects of undernutrition and refeeding on weights of body parts and chemical components of growing Moroccan lambs.

Forty-four intact, male lambs (20 Timahdit and 24 D'man) were used to assess the effects of 22% (from approximately 25 to approximately 20 kg) and 31% (from approximately 25 to approximately 17 kg) live weight loss and the subsequent refeeding to initial BW on changes in body components. Body composition was determined using a serial slaughter technique at 17, 20, and 25 kg live weight during normal growth, weight loss, and refeeding phases. Reduction in live weight from 25 to 20 kg was associated with greater loss of visceral organs (30%) and internal fat (75%) than carcass loss (19%). Further body weight loss (from 20 to 17 kg) involved carcasses to a greater extent than internal organs. The composition of BW loss consisted of 53% water, 28% fat, and 15% protein. Refeeding was associated with a rapid increase in organ weights and less fat regeneration. Although total internal organs recovered only 90% of their original weight, liver and kidneys regained all their weight. At the same slaughter weight, carcass and noncarcass components of refed lambs were leaner because of lower fat content in these components.

Adipose Tissue

The ticking time bomb.

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Acquired Immunodeficiency Syndrome

America's doctors.

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Health Education

Hippocrates lives!

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Education, Medical, Undergraduate

Holistic concepts and the professionalization of public health nursing.

The sociology of knowledge provided the conceptual and methodologic basis for this study of the relationship between the philosophic concept of holism and the professionalization of public health nursing. Set in the context of the history of ideas, the discussion examines the various meanings of holism and the circumstances surrounding their adoption, modification, and use in public health nursing. The nursing literature from the late 1800s to the 1980s was analyzed to explicate the pragmatic consequences of holism for public health nursing, and to examine holism's moral value and its part in establishing and extending public health nursing's professional domain.

History, 19th Century

In vitro muscle cell proliferation and protein turnover as affected by serum from pigs fed antimicrobials.

The effect of antimicrobial supplementation of pigs on the capacity of their sera to influence proliferation and protein turnover in cultured muscle cells was evaluated. Mitogenic activity of sera increased when pigs were fed ASP250 (P less than .005) or carbadox (P less than .001), whereas the mitogenic activity of serum from pigs receiving the basal diet remained unchanged (P = .5). Additionally, sera from ASP250-fed pigs significantly decreased (P less than .001) total cellular protein degradation compared with sera obtained from the same pigs prior to supplementation. Neither ASP250 nor carbadox stimulated proliferation of myogenic cells when added to the culture media. Inclusion of ASP250 in swine diets altered the composition of their sera in a way that stimulated muscle cell proliferation and reduced the rate of protein degradation in cultured myogenic cells. Likewise, the inclusion of carbadox in swine diets increased the ability of their sera to stimulate cultured muscle cell proliferation.

Animals

Antimicrobial supplementation of growing pigs: the effect of porcine sera fractions on in vitro muscle cell proliferation.

Sera obtained from pigs before and after subtherapeutic levels of ASP250 supplementation (pre and post serum pools) have been subjected to comparative fractionation by using gel filtration and affinity chromatography on immobilized Cibacron Blue F3G-A. Comparable serum fractions obtained from pre- and post-ASP250 blood sera were assayed in muscle cell culture bioassays designed to measure their effect on proliferation. Pre- and post-ASP250 sera were subjected to gel filtration and divided into the following fractions: fraction 1, Kav less than .17; fraction 2, Kav = .17 to .41; fraction 3, Kav = .41 to .59. Post-ASP250 fractions 2 and 3 increased proliferation rate in cultured muscle cells to a greater extent than comparable pre-ASP250 fractions (P less than .001). Chromatography of fraction 3 on immobilized Cibacron Blue F3G-A showed that both pre- and post-ASP250 fraction 3 contained a putative inhibitor of myogenic cell proliferation as well as mitogenic factors. However, negative growth factor activity was greater in pre-ASP250 fraction 3 than in post-ASP250 fraction 3 (P less than .05). Additionally, positive growth factor activity was lower in pre-ASP250 fraction 3 than in post-ASP250 fraction 3 (P less than .05). These data suggest that levels and(or) activities of both positive and negative muscle growth factors in serum may be altered by the addition of antimicrobials to the diets of growing pigs.

Animals

Partial purification of a serum fraction from fasted pigs that inhibits proliferation of cultured myogenic cells.

Sera from pigs fasted as little as 24 h appears to contain a factor(s) that inhibits proliferation of myogenic cells in culture. An inhibitor of myogenic cell proliferation has been partially purified from this sera by using a combination of gel filtration and immunoaffinity chromatography. The inhibitory activity elutes from a Sephacryl S-300 column at a Kav (elution minus void volume divided by total minus void column volume) between .41 and .59. Proteins banding at 76 and 67 kilodaltons appear to predominate on sodium dodecyl sulfate polyacrylamide gels of this fraction. Small quantities of each of these proteins were electrophoretically purified and used to elicit production of anti-76 and anti-67 immunoglobulin G in rabbits. These antibodies were used to prepare anti-76 and anti-67 column was particularly useful in isolating the inhibitor because it removed mitogens that made detection of the inhibitory activity difficult. The partially purified inhibitor inhibits proliferation of L6 myogenic cells in a concentration-dependent manner. On sodium dodecyl sulfate polyacrylamide gels, the predominant proteins in the inhibitor fraction band at approximately 63 and 61 kilodaltons. Inhibitors of myogenic cell proliferation may play an important role in balancing the effects of positive growth factors.

Animals

Effect of a career decision-making course on the career planning of nursing students.

This study assessed whether participation in a structured career decision-making course would enhance the career planning of 42 final semester associate degree nursing students. Levels of career planning were measured by the Career Planning Scale (CPS) (Super, Thompson, Lindman, Jordaan, & Myers, 1982), and the Nursing Career Development Inventory (NCDI) (Savickas, 1984). Subjects were randomly assigned to either an experimental or control group. The experimental group received a four-week career decision-making course, which included self-assessment of values, interests, and skills, and information on occupational opportunities in nursing. An ANOVA on the change scores from pretest to post-test revealed significance between the groups on the CPS (p = .002), and on the NCDI (p less than .00001). The experimental group progressed much more in career planning. All subjects were found to have lower levels of career planning than the average college student at pretest. Intercorrelational data and multiple regression analyses indicated that individuals who had worked in a nursing-related field had higher levels of career planning. Overall, the course emerged as being effective in enhancing the career planning of nursing students.

Adult

Effect of sera from fed and fasted pigs on proliferation and protein turnover in cultured myogenic cells.

The effects of fasting on the ability of swine serum to affect proliferation, protein synthesis and protein degradation in L6 myoblast cell culture bioassays were evaluated. Barrows (15 to 20 kg) were fitted with jugular catheters. Blood samples were collected at four evenly spaced intervals between 0800 and 1700 on collection days. Prefast blood samples were obtained on d 1 and 2 of the study, after which pigs were subjected to a 5-d fast. Fasted samples were obtained on the 1st, 3rd and 5th d of the fast (d 3, 5 and 7 of the study). Serum from each collection day was pooled and tested in the proliferation bioassay for each pig. Prefast and fasted serum pools were formed by pooling prefast days (1 and 2) or fasted days (3, 5 and 7), respectively, from all pigs in a study. These pools were tested in the proliferation and protein turnover bioassays as well as in a Somatomedin-C (SmC) radioimmunoassay. Serum from the fasted collection days showed a decrease in mitogenic activity compared with serum from the two prefast days (P less than .001). At high concentrations, sera obtained from fasted pigs inhibited muscle cell proliferation (P less than .001). Additionally, adding fasted serum to control swine serum (CSS) inhibited the mitogenic activity of CSS in a dose-dependent manner (P less than .025). Therefore, fasted sera showed a decreased ability to promote muscle cell proliferation and, in addition, appeared to contain a factor(s) that inhibits muscle cell proliferation. Fasted serum also caused a 21.6% increase in protein degradation compared with prefast serum.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Bicycle safety.

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Accident Prevention

A statistically standardized muscle cell culture bioassay measuring the effect of swine serum on muscle cell proliferation.

We have developed a statistically standardized bioassay for quantifying the effect of swine serum on the proliferation rate of cultured L6 myogenic cells. The intra-assay coefficient of variation for this assay is 2.5%. Over 29 experiments, the relationship between the assays response to 2.5% control swine serum and its response to 2.5% serum plus 10(-7) M insulin is linear (r2 = .9). This relationship can be used to adjust experimental data obtained in different experiment to a common control value so that valid inter-assay comparisons can be made. The inter-assay coefficient of variation is reduced four- to five fold by this adjustment procedure. We believe this standardized assay provides a useful system for identifying and isolating unknown growth factors that affect muscle growth rate in an economically important species.

Animals

Stimulation of in vitro muscle cell proliferation by sera from swine injected with porcine growth hormone.

The proliferation-promoting activity of sera obtained from pigs before and after porcine growth hormone injections was tested in a muscle cell culture bioassay. For 3 d, purified porcine growth hormone (pGH) was administered by intramuscular injection to crossbred barrows. Two levels of pGH were administered: 18 micrograms pGH X kg-1 body weight X d-1 (low dose) or 143 micrograms pGH X kg-1 body weight X d-1 (high dose). Multiple blood samples were withdrawn from jugular catheters for 3 d prior to the injection, during the injection period and for 6 d after the last injection. Although serum pGH levels in low-dose pigs were raised from two to three times pre-injection levels, there was no significant change in serum proliferation-promoting activity or somatomedin-C (SmC), insulin or cortisol levels during or after administration of pGH. In contrast, the proliferation-promoting activity of sera obtained during and after the high-dose pGH injections was higher (P less than .005) than the pre-injection levels. Serum pGH levels were increased approximately 30-fold by 4 h after each injection, and increases in SmC levels were observed 10 to 16 h after the pGH injection. During the injection period SmC levels increased from 1.7 to 4 times pre-injection levels. Insulin and cortisol levels did not change significantly during the 3-d treatment period. We believe that this muscle cell culture bioassay system will be a useful addition to traditional radioimmunoassays and whole animal studies in elucidating the mode of action of pGH in pituitary-intact swine.

Animals

Metabolic characteristics of skeletal muscle from lean and obese Zucker rats.

The purpose of this study was to determine if the metabolic response to obesity and to pair feeding of obese Zucker rats to lean Zucker rats was similar across skeletal muscles. Oxidation of glucose, palmitate and isoleucine was studied in muscle strips in vitro using appropriate 14- carbon substrates as tracers. The plantaris muscle was subjected to histochemical analyses using an alkaline actomyosin ATPase, NADH-tetrazolium reductase and an oil red 0 stain. Soleus muscles from both ad libitum and pair fed obese rats oxidized less glucose to CO2, but released similar amounts of lactate when compared to the soleus muscles of lean rats. Oxidation of glucose was similar in the extensor digitorum longus (EDL) muscle of ad libitum fed obese rats, but lower when pair fed to the intake of lean rats. No differences were apparent in palmitate oxidation to CO2 or in incorporation into lipid (both soleus and EDL muscles), except in the EDL muscle of pair-fed obese rats which exhibited a higher rate for palmitate metabolism when compared with lean rats. Isoleucine oxidation to CO2 was higher in the EDL and plantaris muscles, but similar in the soleus muscle of ad libitum-fed obese rats when compared with lean rats. The magnitude of the difference in isoleucine oxidation was similar when the obese rats were pair fed. No differences in the percentage of plantaris muscle fibers sensitive to alkaline ATPase staining were observed. The plantaris muscle of obese rats, contained a higher proportion of oxidative fibers. These results indicate the great risk in generalizing about metabolic activity of the whole skeletal muscle mass based on observations made on one, or even two, distinct muscles in this animal model. Also, pair feeding of obese to lean Zucker rats did not result in uniform changes in metabolism between muscles of the obese rats.

Animals