Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CONDITIONING”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 469 records · Page 26Linked to original sources

Brainstem lesions and gustatory function: II. The role of the nucleus of the solitary tract in Na+ appetite, conditioned taste aversion, and conditioned odor aversion in rats.

Rats with lesions of the nucleus of the solitary tract (NST) that demonstrated flat concentration-response functions for NaCl and sucrose (T. Shimura, P. S. Grigson, & R. Norgren, 1997) expressed a significant (albeit reduced) salt appetite following sodium depletion, and a normal conditioned taste aversion (CTA) for alanine when paired with lithium chloride-induced toxicosis. Rats with lesions of the NST also could acquire a conditioned odor aversion, but the CTA to alanine was not mediated by odor cues because other rats with NST lesions also demonstrated normal CTA learning even when made anosmic with zinc sulfate. Together, the data suggest that the rostral NST is essential for responding appropriately to increasing concentrations of a tastant, but not for the chemical identification necessary for sodium appetite and CTA learning.

Afferent Pathways↗

Conditioned antisickness: indirect evidence from rats and direct evidence from ferrets that conditioning alleviates drug-induced nausea and emesis.

In a direct test of conditioned antisickness (CAS; B. T. Lett, 1983) theory, the authors measured emesis in ferrets and found those with a history of forward pairings of pentobarbital and lithium to have fewer and shorter bouts of emesis on test, whether induced by lithium or, in a subsequent test, by the highly emetogenic anticancer drug cisplatin. In an indirect test of her CAS theory, B. T. Lett (1992) paired interoceptive (drug) or place cues with lithium chloride toxicosis and found that rats with a forward-pairings history ate less food than controls on a forward-pairing test, consistent with conditioned sickness rather than CAS. But rats eat dirt or clay in response to sickness and adaptively eat small amounts of food when clay is not available. We substituted clay (kaolin) for food in a partial procedural replication of B. T. Lett's (1992, Experiment 1) experiment and found that rats with a history of forward pairings of pentobarbital and lithium ate less kaolin, which is consistent with CAS.

Animals↗

Spinal segment range of motion as a function of in vitro test conditions: effects of exposure period, accumulated cycles, angular-deformation rate, and moisture condition.

BACKGROUND: The purpose of this study was to thoroughly evaluate the relationship of possible mechanical and environmental conditions in the testing of spinal joint segments, including ambient-temperature exposure, accumulated test cycles, angular-deformation rate, and moisture condition on the motion characteristics of joints, with the example of isolated spinal segments. METHODS: In one test, controlled loading was applied to six motion segments every 8 hours in each of the primary anatomical directions while moisture was held constant. In a second test, 18 specimens were divided equally into moisture-static, air-exposed, and slowly irrigated groups and loaded to 500 cycles. In a third test, a similar sample was tested over a range of angular-deformation rates (0.6-5.1 degrees/second). RESULTS: Range of motion (ROM) increased steadily with ambient-temperature exposure time, resulting in a 10% change at about 20 hours but was most stable in the moisture-static group over both accumulated load cycles and loading rate changes. CONCLUSIONS: The most critical factor for functional testing of spinal segments appears to be length of exposure.

Animals↗

On a general class of conditional tests for family-based association studies in genetics: the asymptotic distribution, the conditional power, and optimality considerations.

Family-based association tests (FBATs) provide simple and powerful tests to detect association between a genetic marker and a disease-susceptibility locus, manifest in subjects by a phenotype or disease trait. Here we propose a new class of conditional tests for family-based association studies that includes most of the established tests and their generalizations. The class of tests is very general; it can be applied to longitudinal and multivariate traits or phenotypes, multiple genetic markers, and many other situations not yet discussed in the literature. For any test in this class, we derive the asymptotic distribution under the null hypothesis, the conditional power under any alternative hypothesis, and the optimal offset for single degree of freedom tests. The proposed methodology is illustrated with a genetic study of asthma.

Asthma↗

Bacteriorhodopsin crystal growth in reduced gravity--results under the conditions, given in CPCF on board of a Space Shuttle, versus the conditions, given in DCAM on board of the Space Station Mir.

For the purpose of bio-electronics, bacteriorhodopsin was crystallized into two habits through liquid-liquid-diffusion, namely individual needles of up to 1.9 mm in length and needle bunch-like clusters of up 4.9 mm in total length. In both the reduced gravity experiments performed, the morphology of the individual needles (crystal form A) had improved in terms of sharp needle edges and compact needle packing, compared to the parallel ground controls. For the long duration wide range low gravity condition in the "Diffusion-controlled Crystallization Apparatus for Microgravity (DCAM)" on Mir (STS-89 up), needle bunches on average were longer there than on the ground, while the compactness of the clusters, i.e. the average ratio of clustered length to clustered width was the reverse. Some exceptionally large individuals needles were grown in DCAM. For the "Commercial Protein Crystallization Facility (CPCF)" in short duration high definition microgravity conditions during a science mission of the Space Shuttle Discovery (STS-95), size and shape of the individual needles were homogeneous and superior to those of both the parallel ground controls and the results in DCAM. In CPCF, the average volume of the individual needles in suspension was increased by 50% in microgravity compared to those in the ground control.

Ammonium Sulfate↗

Drug-cue conditioning to external stimulus conditions.

Rats were trained to discriminate 0.04 mg/kg fentanyl from saline in a 2-lever procedure, and to discriminate 10 mg/kg pentobarbital from saline in a maze procedure. Stimulus generalization experiments in rats trained in this double discrimination indicate that the internal cues produced by these training drugs can be conditioned to the external stimulus conditions associated with the different discrimination procedures.

Animals↗

Optimal conditions for the generation of monoclonal antibodies using primary immunisation of mouse splenocytes in vitro under serum-free conditions.

We have further optimised the serum-free in vitro immunisation system described by Ossendorp et al. (J. Immunol. Methods 91, 257, 1986) for the generation of hybridomas secreting specific antibodies. Thyroglobulin and the hapten 2-phenyl-5-oxazolone coupled to chicken serum albumin were used as antigens. For an optimal outgrowth of antigen-specific B cells the presence of T cells, thymocyte-conditioned medium and antigen are required. The addition of supernatant from EL-4 cells (stimulated by phorbolmyristate acetate) inhibits the outgrowth of antigen-specific B cells. Using six-well plates with a surface area of 10 cm2 per well, an optimal IgM response was obtained when 10(7) splenocytes in a total volume of 2 ml/well were cultured for 3 days in the presence of antigen and thymocyte-conditioned medium. Increasing the concentration of cells whilst maintaining a constant surface area resulted in a decreased response.

Animals↗

Thresholds of elicitation depend on induction conditions. Could low level exposure induce sub-clinical allergic states that are only elicited under the severe conditions of clinical diagnosis?

While numerous studies have examined dose/response relationships occurring in the experimental induction of contact allergic dermatitis, fewer have examined the effects of varying the doses of both induction and challenge. Recently published studies have however done this and they all show the same remarkable observation: the threshold of elicitation decreases as the doses used to induce the allergy increase. This has important implications. One is that it may be more complicated to determine clear threshold doses below which allergic responses are not seen. It is also proposed that normal exposure to weak allergens such as some fragrance materials may induce "sub-clinical" allergic states which will not be elicited under these same exposure conditions but which may become apparent under the more severe conditions of clinical diagnosis. This may explain why the prevalence of Patch test reactions to some fragrance materials is apparently increasing in the absence of any clearly documented "epidemic" of consumer complaints.

Allergens↗

Alterations of markers related to synaptic function in aging rat brain, in normal conditions or under conditions of long-term dietary manipulation.

Neurochemical alterations of markers related to synaptic function are potential candidates for age-related impairment of brain function and cognition. The process of aging, including brain aging, can be counteracted to some degree by maintaining animals in long-term conditions of caloric restriction, or supplementing their diet with antioxidant substances. We report here that the age-related decline of the cholinergic and GABAergic systems, that takes place in some CNS regions of aged rats, is not affected by maintaining them under conditions of dietary restriction and, therefore, of reduced calorie intake, from the 12th to the 30th month of age. We also notice the same lack of effect by adding, during the same period, the aging rat diet with the potential antioxidant substance, N-acetylcysteine (NAC). The same dietary manipulations are also unable to counteract the derangement of the first step of the main biosynthetic pathway for polyamines, putative neuromodulators in the CNS, that occurs in the aged spinal cord. Some age-related alterations in the expression of different subunits of the NMDA-type glutamate receptors in some CNS regions of aged rats were instead, at least in some cases, counteracted by long-term dietary manipulation.

Acetylcysteine↗

Effect of nematode burden as assessed by means of faecal egg counts on body condition in goats farmed under resource-poor conditions in South Africa.

A longitudinal study was conducted of the nematode faecal egg counts (FECs) and body condition scores (BCSs) of goats of resource-poor farmers at Rust de Winter, Gauteng Province, Impendle, KwaZulu-Natal Province, and Kraaipan, North-West Province, South Africa. Periods of higher FECs occurred from December/January to March/April at Rust de Winter and at Impendle and from January to March at Kraaipan. Seasonal variations in body condition were evident in the goats at Impendle with the animals showing lower BCSs from June to October. The goats at Rust de Winter and at Kraaipan did not show clear seasonal variations, although the goats at Rust de Winter showed lower BCSs from mid-July to early December. The BCSs for Rust de Winter where the animals were grazed on a private farm were generally higher than those of the other sites, where communal grazing is practised.

Animals↗

Growth condition-dependent sensitivity, photodamage and stress response of Chlamydomonas reinhardtii exposed to high light conditions.

Different substrate conditions, such as varying CO(2) concentrations or the presence of acetate, strongly influence the efficiency of photosynthesis in Chlamydomonas reinhardtii. Altered photosynthetic efficiencies affect the susceptibility of algae to the deleterious effects of high light stress, such as the production of reactive oxygen species (ROS) and PSII photodamage. In this study, we investigated the effect of high light on C. reinhardtii grown under photomixotrophy, i.e. in the presence of acetate, as well as under photoautotrophic growth conditions with either low or high CO(2) concentrations. Different parameters such as growth rate, chlorophyll bleaching, singlet oxygen generation, PSII photodamage and the total genomic stress response were analyzed. Although showing a similar degree of PSII photodamage, a much stronger singlet oxygen-specific response and a broader general stress response was observed in acetate and high CO(2)-supplemented cells compared with CO(2)-limited cells. These different photooxidative stress responses were correlated with the individual cellular PSII content and probably directly influenced the ROS production during exposure to high light. In addition, growth of high CO(2)-supplemented cells was more susceptible to high light stress compared with cells grown under CO(2) limitation. The growth of acetate-supplemented cultures, on the other hand, was less affected by high light treatment than cultures grown under high CO(2) concentrations, despite the similar cellular stress. This suggests that the production of ATP by mitochondrial acetate respiration protects the cells from the deleterious effects of high light stress, presumably by providing energy for an effective defense.

Acetates↗

Strength and conditioning practices of Major League Baseball strength and conditioning coaches.

This study describes the results of a survey of the practices of Major League Baseball strength and conditioning (MLB S&C) coaches. The response rate was 70.0% (21 of 30). This survey examines (a) background information, (b) physical testing, (c) flexibility development, (d) speed development, (e) plyometrics, (f) strength/power development, (g) unique aspects, and (h) comments. Results indicate, in part, that coaches assess an average of 3.6 parameters of fitness, with body composition testing being the most commonly assessed parameter. All coaches use a variety of flexibility development strategies. All coaches use speed development strategies, with form running drills being the most common. Twenty of 21 (95.2%) coaches employ plyometric exercises with their athletes. Eighteen of 21 (85.7%) of MLB S&C coaches follow a periodization model (PM). Five of 21 coaches (23.8%) indicated that their athletes use Olympic-style lifts. The squat and its variations and the lunge and its variations were most frequently identified as the first and second most important exercises used to train the athletes. This survey provides detailed information about strength and conditioning practices at the most competitive level of baseball and serves as a review, as well as a source of applied information and new ideas.

Baseball↗

Genetic parameters for weight, weight adjusted for body condition score, height, and body condition score in beef cows.

Weight (CW, n = 61,798), weight adjusted for condition score (WA), hip height (CH, n = 56,494), and condition score (CS, n = 61,434) of cows (2 through 8 yr of age) produced by crosses of 22 sire breeds with Angus and Hereford dams in the first four cycles of the Germplasm Evaluation (GPE) Program at the U.S. Meat Animal Research Center were used to estimate genetic parameters with REML. The model included sire breed, dam breed, age in years, season of measurement (1 to 4) and their interactions, and year of birth and pregnancy-lactation code (PL) as fixed effects for CW and CS. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects. Univariate analyses of all data, by season and by year of age, bivariate analyses between pairs of seasons and ages (2 to 6), and between traits were done. Estimates of heritability and repeatability over all ages were 0.49, 0.54, 0.68, and 0.16, and 0.65, 0.67, 0.75, and 0.30 for CW, WA, CH, and CS, respectively. Corresponding estimates for each age and season were similar for all traits and cycles. Estimates of genetic and permanent environmental correlations were close to unity for all pairs of seasons and traits. Genetic correlations were greater than 0.92 for all pairs of ages for CW, WA, and CH, and greater than 0.67 for CS. Genetic correlations were 0.80, 0.86, 0.43, and -0.04 for CW-CH, WA-CH, CW-CS, and CH-CS, respectively. Results suggest that repeatability models can be used to model weights and heights in this population.

Age Factors↗

Comparisons of Angus, Charolais, Galloway, Hereford, Longhorn, Nellore, Piedmontese, Salers, and Shorthorn breeds for weight, weight adjusted for condition score, height, and condition score of cows.

Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breedgroup as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P < 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1 cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1 Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicus heterosis for size.

Animal Nutritional Physiological Phenomena↗

The effect of long-term housing in an aviary and battery cages on the physical condition of laying hens: body weight, feather condition, claw length, foot lesions, and tibia strength.

The physical condition of laying hens housed for 3 yr in either traditional battery cages or an aviary was compared. Aviary hens were significantly lighter than those in cages (2,021 vs 2,241 g; P = .0001), despite having consumed slightly more feed (121 vs 116 g per bird per d, P = .16). Caged hens had poorer feather cover (P = .0001); 39% of caged birds had denuded areas greater than 5 cm2, whereas 68% of aviary hens had complete plumage. The length of both center front and rear claws was significantly greater in caged hens (36.3 vs 30.3 mm, P = .001 and 19.2 vs 16.1 mm, P = .012, respectively). The total number of foot lesions did not differ with housing system; however, caged hens had significantly more toe injuries (P < .001), and aviary birds had more injuries on the soles of their feet (P = .005). All aviary birds with foot lesions had only a single lesion, whereas one-sixth of caged hens with lesions had more than one. No difference in tibial breaking strength was found due to housing system. Overall, the results suggest that aviary systems can offer some distinct advantages over traditional battery cages with regard to the physical condition of laying hens, given a high level of management.

Animals↗

Haemonchus spp. in sheep farmed under resource-poor conditions in South Africa--effect on haematocrit, conjunctival mucous membrane colour and body condition.

A longitudinal study was conducted on the differential faecal egg counts, haematocrits and body condition scores of sheep belonging to resource-poor farmers at Rust de Winter, Gauteng province, and Kraaipan, North West Province, South Africa. The animals were scored for level of anaemia using the FAMACHA method, an assay for the clinical evaluation of anaemia caused by Haemonchus spp. Periods of higher Haemonchus egg counts occurred from October to March for sheep at Rust de Winter and from September/October to February or April for sheep at Kraaipan. Lower haematocrit values were registered during these periods as was a higher incidence of anaemic conjunctival mucous membrane colour scores compared to the period April to September. No clear relationship between the faecal egg counts and the body condition scores was evident. Although wider application of the FAMACHA system in sheep raised by resource-poor farmers should be investigated, the present study indicates that this method may certainly prove to be a valuable worm control strategy for such livestock owners.

Anemia↗

Special conditions: modified Boeing Model 767-200 and -300 series airplanes; installation of a medical oxygen system utilizing liquid oxygen--Federal Aviation Administration. Final special conditions; request for comments.

These special conditions are issued to E-Systems for design of Civil Reserve Air Fleet aeromedical evacuation ship set kits used to modify Boeing Model 767-200 and -300 series airplanes. Removal of existing passenger seats and installation of the kit will result in these airplanes being equipped with an aeromedical evacuation interior that can accommodate up to 111 litter patients and their attendants. The aeromedical evacuation ship set kit includes an additional oxygen system, utilizing liquid oxygen for storage, that provides medical oxygen for the litter patients. The applicable regulations do not contain adequate or appropriate safety standards for the design and installation of liquid oxygen systems. These special conditions contain the additional safety standards which the Administrator considers necessary to ensure that the design and installation of the liquid oxygen system is such that a level of safety equal to that intended by the applicable regulations is provided.

Aircraft↗

Morning spot and 24-hour urinary 6 beta-hydroxycortisol to cortisol ratios: intraindividual variability and correlation under basal conditions and conditions of CYP 3A4 induction.

A single spot urine collection to measure the ratio of 6 beta-hydroxycortisol (6 beta-OHC) to free cortisol (C) has been proposed as a research tool for the assessment of CYP3A4 induction. However, intraindividual variability in 6 beta-OHC/C under basal conditions and conditions of induction has not been prospectively evaluated, and findings on the correlation between morning spot and 24-hour urinary ratios have been conflicting. In this study, the variability in morning spot and 24-hour urinary 6 beta-OHC/C ratios was assessed in 15 healthy adult male volunteers before, during, and after oral administration of rifampin 600 mg once daily for 14 days. In addition, the correlation between morning spot and 24-hour urinary ratios measured under baseline, maximum induction, and postinduction was determined. Intraindividual coefficients of variation (CVs) at baseline for the morning spot and 24-hour ratios were 54.3% and 57.1%, respectively, and were not changed significantly during induction. No significant differences were detected in the variability between the morning spot and 24-hour ratios at baseline, maximum induction, or postinduction. A good correlation (r = 0.61, p < 0.0001) was detected between the mean morning spot and 24-hour urinary ratios. Mean (+/- SEM) percent increases in the morning spot and 24-hour ratios at maximum induction relative to baseline were 320% +/- 73% and 137% +/- 30%, respectively (p = 0.019). All 15 subjects had an increase in the mean morning spot ratio at maximum induction relative to baseline, whereas 12 subjects showed an increase in the mean 24-hour ratio. The time course of changes in the mean morning spot urinary ratio in response to a 14-day course of rifampin was also similar to that reported previously in a study using 24-hour urine collections. These findings suggest that measurement of the morning spot urinary 6 beta-OHC/C ratio is an effective and efficient method for evaluating the potential of investigational agents to induce CYP3A4.

Adolescent↗