Effect of ergotamine and ergonovine on plasma concentrations of thyroid hormones and cortisol in cattle

Plasma samples from two experiments were processed to determine whether ergot alkaloids associated with endophyte-infected tall fescue altered peripheral thyroxine (T4), triiodothyronine (T3), or cortisol concentrations in cattle. In Exp. 1, seven Angus steers (294 kg) received i.v. bolus injections of saline (SAL), ergonovine maleate (7 mg; EM), or ergotamine tartrate (7 mg; ET) at weekly intervals, and they received all treatments during the study. Blood was sampled every 15 min for 5 h, and treatments were given after h 1. Mean ambient temperature was 34 degrees C. Treatment x time affected plasma concentrations of T3 (P < .05) and of cortisol (P < .001) but not that of T4 (P > .2). Plasma T3 concentrations were not affected by SAL, whereas concentrations increased (P < .01) after either EM or ET treatment. Plasma cortisol concentrations were not altered by SAL or EM, but they were increased (P < .001) by ET treatment. In Exp. 2, six Holstein cows (499 kg) nursing calves received a bolus i.v. injection of SAL, EM (9.5 mg), or ET (9.5 mg) per estrous cycle, and all treatments were given over three cycles. Blood was sampled every 20 min for 5 h; treatments were given after h 1. Mean ambient temperature was 26 degrees C. Treatment x time affected T3 (P = .08) and cortisol (P < .001) and tended to influence (P = .16) T4 concentrations. Plasma T3, T4, and cortisol concentrations were not influenced by SAL treatment. Plasma T3 was higher (P < or = .01) after EM or ET treatment compared with pretreatment concentrations. Concentrations of T4 during the 4 h after EM and ET were increased (P < .001) compared with pretreatment. Plasma cortisol concentrations were not altered by EM but were increased (P < .001) by ET. Ergot alkaloids implicated as contributing agents to fescue toxicosis alter plasma concentrations of hormones important to metabolic and thermoregulatory functions in cattle.     

Clinical utility of the polymerase chain reaction in the diagnosis of extrapulmonary tuberculosis

This study examines the diagnostic utility of the polymerase chain reaction (PCR) in 156 patients (five human immunodeficiency virus (HIV) seropositive) suspected of extrapulmonary tuberculosis. The results of PCR in 226 samples from 11 different sites were compared with the results of microscopy and culture. Positive culture results were predicted in 86% of samples by PCR but in only 31% by microscopy. Specificity of PCR was 92%. In cases with culture-proven tuberculosis, PCR identified all 11 microscopy positive cases and 19 of 24 (79%) of the microscopy-negative cases. In four patients, PCR excluded the diagnosis of tuberculosis in microscopy-positive samples, which were later shown to contain mycobacteria other than Mycobacterium tuberculosis or laboratory contaminants. In 20 patients (microscopy, PCR and culture negative) a trial of antituberculous drugs was given, but patients showed no improvement and treatment was stopped. In 17 patients, all culture negative (in nine PCR was positive, three of whom also had positive microscopy) the diagnosis was probable tuberculosis based on clinical findings and response to treatment. This polymerase chain reaction has a much higher sensitivity than microscopy and can facilitate therapeutic decisions for those with suspected extrapulmonary tuberculosis.     

Templating of crystallization and shear-induced self-assembly of single-wall carbon nanotubes in a polymer-nanocomposite

We report the appearance of a novel self-assembling of a fraction of single-wall carbon nanotubes (SWCNT) within a SWCNT-polymer nanocomposite subjected to flow fields upon injection molding processing. By combining X-ray diffraction and Raman spectroscopy techniques, both working on a microfocus fashion, we probe that a fraction of the thinnest SWCNT self-assembles into a rectangular lattice in the sample regions where the shear stress induces the highest levels of nanotube aggregation. Additionally, we demonstrate that a modest amount in weight of nanotubes is enough to template the morphology of crystallization during flow providing a method to obtain a highly desirable fiber-like morphology.     

In vitro effects of urease inhibitors on rate of urea hydrolysis in soils

We studied the effect of urease inhibitors on the urea hydrolysis in some Sundanese soils belonging to the orders of Vertisol and Entisol. The hydrolysis showed a lag period of about 3 days and its rate (Y) per unit time (t) could be described by a two constants exponential equation of the general form Y = K₁t^K ₂. Statistical analysis showed that the intercept K₁ (rate of urea hydrolysis) was significantly affected by soil type rather than treatment. It seems that K₁ is associated with the soils' initial urease activity as it closely correlates with the Michaelis constant (km).The gradient, K₂, being significantly affected by soil type as well as treatment is probably associated with the induced urease activity with time and it, therefore, varied with variations in soils and treatments. Of the so-called urease inhibitors used in this study Ca(OH)₂, p-benzoquinone (PBQ) and orthophosphoric acid (OP) only PBQ reduced urea hydrolysis while the other chemicals have effects possibly related to modifying the soil pH. Inhibitor treated soils had substantial amounts of unacounted for N which was believed to be present, presumably, in the form of carbamate.Contribution from the Department of Biochemistry and Soil Science, Faculty of Agriculture, Shambat, Sudan.     

View-based propagator derivation

When implementing a propagator for a constraint, one must decide about variants: When implementing min, should one also implement max? Should one implement linear constraints both with unit and non-unit coefficients? Constraint variants are ubiquitous: implementing them requires considerable (if not prohibitive) effort and decreases maintainability, but will deliver better performance than resorting to constraint decomposition. This paper shows how to use views to derive propagator variants, combining the efficiency of dedicated propagator implementations with the simplicity and effortlessness of decomposition. A model for views and derived propagators is introduced. Derived propagators are proved to be perfect in that they inherit essential properties such as correctness and domain and bounds consistency. Techniques for systematically deriving propagators such as transformation, generalization, specialization, and type conversion are developed. The paper introduces an implementation architecture for views that is independent of the underlying constraint programming system. A detailed evaluation of views implemented in Gecode shows that derived propagators are efficient and that views often incur no overhead. Views have proven essential for implementing Gecode, substantially reducing the amount of code that needs to be written and maintained.     

The Employee Health Care Value Survey: round one

In a groundbreaking arrangement, a consortium of large employers--the Xerox, GTE, and Digital Equipment Corporations--launched the Employee Health Care Value Survey during fall 1993. Completed by 24,306 employees, this survey was used to develop comparable methods for assessing corporate health care benefit strategies. It also enabled fair comparisons of thirty-two health plans across the country on more than sixty criteria. Variation in performance among plans was substantial, with managed care plans--particularly prepaid group practices and individual practice associations (IPAs)--recording the most favorable rankings on disenrollment, overall satisfaction, and other measures of "bottom-line performance." Variation in enrollees' health among plans was more modest, with indemnity enrollees posing a somewhat greater illness burden to their plans than enrollees of other plan types. The employers and evaluated health plans are now using the results for multiple purposes, including quality improvement initiatives, employee-based plan performance reports, employee contribution strategies, and health promotion programs.     

Service differentiation in a single-period inventory model with numerous customer classes

We study critical-level inventory-management policies as means to provide differentiated (\(\alpha \) and \(\beta \)) service levels to more than two classes of customers. First, we derive closed-form expressions for the service levels of a single-period critical-level policy with an arbitrary number of customer classes (with Poisson demand). Based on the service-level expressions, we derive additional structural insights and provide an efficient algorithm with which to compute the essential system parameters, that is, the minimum required starting inventory and the associated critical levels. Based on these results, we conduct numerical experiments and develop structural insights into the system’s behavior.     

Management of stage III breast cancer

The influence of several methodological factors on mean values of sister chromatid exchanges (SCEs) and micronuclei (MN) in peripheral lymphocytes of 1,650 subjects was analyzed. Donors belonged to a general healthy population living in Pisa and in two nearby small cities: Cascina and Navacchio (Ca-Na). Blood samples were collected over a period of 29 months and processed in three different laboratories of the some institute. Slides were analyzed by several scorers. Our data showed that lymphocyte proliferation indexes (PIs) and baseline mean values of SCEs were affected mainly by sampling period. This factor accounted for a percentage ranging from roughly 10% (Pisa) to 20% (Ca-Na) of total SCE variance and from roughly 10% (Pisa) to 13% (Ca-Na) of total PIs variance. A marginal effect was attributable to the different laboratories involved (maximum 3% for SCEs and 7% for PIs). The sampling period variable included many sources of variability such as culture media batches, fetal calf serum, PHA, BrdUrd, and seasonality. MN counts revealed a more marked dependence on processing laboratories. This factor accounted for a percentage of roughly 10% (Pisa and Ca-Na) of total variance, while the sampling period was marginally effective (about 1-4% of total variability). Because laboratories were equipped and supplied with the same materials and consumables and technicians were rotated constantly, the only variable ascertained was represented by the three different models of CO2 incubators used for lymphocyte culturing. When "month" and "incubator" variables were considered jointly, experimental variability accounted for 15-20% of total variance, both for PIs and mean values SCEs and MN. The variability due to slide scoring was reduced by assigning each slide to five different scorers and matching low with high scorers in each group. Present data show that when the study is performed under these controlled conditions, about 20% of total interdonor variability can be explained by experimental or seasonal factors.     

Yearly stepwise increments of the growth hormone dose results in a better growth response after four years in girls with Turner syndrome. Dutch Working Group on Growth Hormone

To optimize the growth promoting effect of growth hormone (GH), 65 previously untreated girls with Turner syndrome (TS), chronological age (CA) 2-11 yr, were randomized into 3 dosage regimen groups: A, B, and C, with a daily recombinant-human GH dose during 4 study years of 4-4-4-4, 4-6-6-6, and 4-6-8-8 IU/m2 b.s. The first GH dosage increase in groups B and C resulted in a significantly higher mean height velocity (HV) compared with constant dose group A. During the third year, when the dose was raised again only in group C, mean HV was significantly higher in groups B and C than in group A, and in group C compared with group B. In year 4 only group C mean HV remained significantly higher than group A. The pattern of change in HSDSCA (Dutch-Swedish-Danish Turner references) was identical; however, in year 4 mean delta HSDSCA in group B also remained significantly higher than group A. After 4 yr GH treatment, the following was determined. 1) The mean delta HSDSCA was significantly higher for groups B and C compared with group A, but not significantly different between groups B and C. 2) Although significantly higher compared with estimated values for untreated Dutch girls with TS, bone maturation of the GH treated girls was not significantly different between groups. 3) It was positively related with the degree of bone age (BA) retardation at start of study and negatively with baseline CA. 4) Both the modified Index of Potential Height (mIPHRUS) and a recently developed Turner-specific final height (FH) prediction method (PTSRUS), based on regression coefficients for H, CA, and bone age, showed significant increases in mean FH prediction, without significant differences between groups. PTSRUS values were markedly higher than the mIPHRUS values. Dose dependency could be shown for the area under the curve (AUC) for GH, but delta HSDSCA was not linearly related with AUC. Baseline GH binding protein (BP) levels were in 84% of the cases within the normal age range; the decrease in mean levels after 6 months GH was not significant. Mean insulin-like growth factor I (IGF-I) and IGFBP-3 plasma levels increased significantly, without significant differences between groups. delta HSDSCA during GH was dependent on IGF-I plasma levels at baseline and during the study period, beta-0.002 and beta-0.0004. Thus, a stepwise GH-dosing approach reduced the "waning" effect of the growth response after 4 yr treatment without undue bone maturation. FH prediction was not significantly different between treatment groups. Irrespective of the GH dose used, initiation of GH treatment at a younger age was beneficial after 4 yr GH when expressed as actual cm gained or as gain in FH prediction, but was not statistically significant when expressed as delta HSDSCA over the study period.