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PubMed2006

Effect of egg turning angle and frequency during incubation on hatchability and incidence of unhatched broiler embryos with head in the small end of the egg.

The effect of turning angle (from vertical) and the interaction with turning frequency during incubation on fertile hatchability, embryonic mortality, and the incidence of embryos with head in the small end of the egg (malpositioned) was studied in 2 experiments comprising 2 trials each to determine if a turning angle of less than 45 degrees could be successful. Hatching eggs from commercial broiler breeder flocks from 55 to 61 wk of age were utilized, and turning was for 18 d. Eggs were subjected to turning angles of 35, 40, or 45 degrees, with a turning frequency of 24 times daily (24x) in Experiment 1. Turning angle had no effect on fertile hatchability. However, the incidence of separately enumerated, malpositioned embryos was increased by the 35 degrees angle, compared with both the 40 and 45 degrees angles in Experiment 1. Eggs were subjected to turning angles (from vertical) of 35 degrees, with a turning frequency of either 24x or 96x daily, or 45 degrees, with 24x turning in the 2 trials of Experiment 2. Turning angle and frequency had no effect on fertile hatchability or embryonic mortality, but the incidence of separately enumerated, malpositioned embryos was increased by the 35 degrees angle with 24x turning, compared with the 35 degrees angle with 96x turning, and the 45 degrees angle, with 24x turning, in Experiment 2. These data demonstrated that the incidence of malpositioned embryos was increased by a reduced turning angle, but that this effect was ameliorated by a concomitant increase in turning frequency.

Aging↗

PubMed1983

Intermolecular potentials for alpha-glycine from Raman and infrared scattering measurements.

The frequencies of intermolecular modes in alpha-glycine-d0 and -d5 have been measured at 300 and 85 K by Raman and infrared scattering techniques. These frequencies were analyzed in terms of simple analytic interatomic potentials. Buckingham potentials were assumed for the nonbonded and hydrogen-bond interactions, and Coulomb and screened Coulomb potentials were assumed for the electrostatic interactions. The observed frequencies are well described by the simple model and the parameters of the hydrogen-bond potentials and the molecular charge distribution were determined from the analysis.

Glycine↗

PubMedDate not supplied

Effects of testosterone on aggressive behaviour after social mixing in male lambs.

The aim of this article was to study the effects of testosterone administration on the aggressive behaviour of male prepubertal lambs after mixing unacquainted individuals. Forty male lambs from two different flocks (1 and 2), 20-22 kg body weight and 10-12 weeks old, were distributed into four groups: C1 and C2 (control groups), and T1 and T2 (testosterone-treated groups). Groups C1 and T1 came from flock 1, while groups C2 and T2 came from flock 2. Animals in groups T1 and T2 were given 250 mg of testosterone enantate intramuscularly on the first experimental day. Animals from the same flock were kept as a group during the first 15 days; on Day 16, control animals (C1 and C2) were moved into one pen and testosterone-treated animals (T1 and T2) into another one, where they were kept for 3 additional days. Aggressive interactions and hormone plasma levels were recorded both before and after social mixing. Before social mixing, testosterone did not modify the frequency of aggressive interactions, while it increased the probability of an animal to receive an aggression. After social mixing testosterone-treated animals initiated and received more aggressions than control animals. Moreover, after social mixing, testosterone-treated animals directed their aggressions mainly towards unfamiliar animals, whereas control animals directed theirs aggressions towards familiar and unfamiliar animals in the proportion expected by chance. It is suggested that the effects of testosterone on aggressive behaviour are context dependent, and that testosterone increases an animal's tendency to establish dominance relationships, rather than its aggressiveness per se.

Aggression↗

PubMed1992

New insights into behavioral evaluation of audiogenic seizures. A comparison of two ethological methods.

Wistar male rats were tested for susceptibility to audiogenic seizures (AS) and classified into sensitive (S) and resistant (R) groups by means of a severity index (SI). Susceptible animals were those which displayed wild running behavior (gyri, jumping and atonic falling) followed by generalized tonic-clonic seizures and consequently had an SI = 0.85 (maximum; n = 10). Resistant animals were considered those with no convulsive response to the acoustic stimulation having an SI = 0 (n = 10). Behavioral sequences of susceptible and resistant animals were recorded and analyzed using two ethological methods which basically considered behavior item frequency and statistical interactions of sequential patterns. Both methods include the concept of cluster analysis but do not include a simultaneous analysis of behavior frequency and time spent in each behavior. Thus, a third method is proposed to graphically display both frequency and temporal patterns in a more complex cluster analysis. The methods discussed here allow comparisons of behavioral sequences in a given experimental situation such as susceptible against resistant animals, acute and chronic seizures, comparison of pre- and postdrug effects, etc. Consequently, they may be the micro-behavioral substrate for correlation with contemporary molecular analysis of epileptic seizures.

Acoustic Stimulation↗

PubMed2004

Distraction sneakers decrease the expected level of aggression within groups: a game-theoretic model.

Hawk-dove games have been extensively used to predict the conditions under which group-living animals should defend their resources against potential usurpers. Typically, game-theoretic models on aggression consider that resource defense may entail energetic and injury costs. However, intruders may also take advantage of owners who are busy fighting to sneak access to unguarded resources, imposing thereby an additional cost on the use of the escalated hawk strategy. In this article we modify the two-strategy hawk-dove game into a three-strategy hawk-dove-sneaker game that incorporates a distraction-sneaking tactic, allowing us to explore its consequences on the expected level of aggression within groups. Our model predicts a lower proportion of hawks and hence lower frequencies of aggressive interactions within groups than do previous two-strategy hawk-dove games. The extent to which distraction sneakers decrease the frequency of aggression within groups, however, depends on whether they search only for opportunities to join resources uncovered by other group members or for both unchallenged resources and opportunities to usurp.

Aggression↗

PubMed1996

The influence of lexical and conceptual constraints on reading mixed-language sentences: evidence from eye fixations and naming times.

In two experiments, we explored the degree to which sentence context effects operate at a lexical or conceptual level by examining the processing of mixed-language sentences by fluent Spanish-English bilinguals. In Experiment 1, subjects' eye movements were monitored while they read English sentences in which sentence constraint, word frequency, and language of target word were manipulated. A frequency x constraint interaction was found when target words appeared in Spanish, but not in English. First fixation durations were longer for high-frequency Spanish words when these were embedded in high-constraint sentences than in low-constraint sentences. This result suggests that the conceptual restrictions produced by the sentence context were met, but that the lexical restrictions were not. The same result did not occur for low-frequency Spanish words, presumably because the slower access of low-frequency words provided more processing time for the resolution of this conflict. Similar results were found in Experiment 2 using rapid serial visual presentation when subjects named the target words aloud. It appears that sentence context effects are influenced by both semantic/conceptual and lexical information.

Adult↗

PubMed2003

A summary of Food and Drug Administration-reported adverse events and drug interactions occurring during therapy with omeprazole, lansoprazole and pantoprazole.

BACKGROUND: Pantoprazole is claimed to have a lower potential for drug interaction than other proton pump inhibitors. AIM: To estimate the frequency of adverse events and drug interactions reported to the Food and Drug Administration in patients receiving omeprazole, lansoprazole or pantoprazole. METHODS: The study involved a search of the Food and Drug Administration's database for adverse events and drug interactions with omeprazole, lansoprazole or pantoprazole as primary or secondary suspect drug. An estimate of the amount of drug dispensed during the adverse event collection period (from US drug launch) was obtained from the International Medical Statistics health database. RESULTS: Of the suspected drug interactions recorded, vitamin K antagonist interactions, although rare, were the most common. The frequency of vitamin K antagonist interactions was 0.09 per million packages for omeprazole and 0.11 per million packages for lansoprazole and pantoprazole. Interactions with benzodiazepines or phenytoin were even rarer, being reported in less than 10 patients on each proton pump inhibitor. CONCLUSION: The frequency of reported drug interactions was low for omeprazole, lansoprazole and pantoprazole and vitamin K antagonist interactions were by far the most common. These potentially important drug interactions, although rare, were no less frequent on pantoprazole than on omeprazole or lansoprazole, suggesting a class effect.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed1995

Bioacoustics of a miniature cricket, Cycloptiloides canariensis (Orthoptera: Gryllidae: Mogoplistinae)

Male crickets, Cycloptiloides canariensis (body length 5 mm), stridulate with their forewings, which are hidden during rest under the large shield-like pronotum. The wings are opened into the stridulatory position by bending the body between the pro- and mesothorax. The song is a 2 s trill composed on average of 260 pulses (syllables) with a carrier frequency of about 6 kHz. The sound-emitting structures on the wings have been studied by laser vibrometry and particle dusting. A distinct membrane area, which includes a prominent mirror cell, acts as a resonator, amplifying the fundamental carrier frequency produced by interactions between the file and plectrum. The resonating membrane is extremely thin (mirror cell thickness 0.2 µm), which is a physical requirement for maintaining the carrier frequency in the cricket-specific range. Covering the wings after singing is probably an adaptation to protect these delicate structures from damage by mechanical contact during social interactions, especially mating.

Journal Article↗

PubMed1997

Relationship between training frequency and subcutaneous and visceral fat in women.

We examined the interaction of two different frequencies of aerobic exercise training (30 min at 50-60% of maximal heart rate reserve per session) and a self-administered caloric restriction program on the changes in subcutaneous (SFM) and visceral (VFM) fat mass over a period of 13 wk. Twenty-six sedentary young women (27.9% body fat) were randomized into three groups: nonexercising control (C, N = 8); 1-2 sessions/wk plus a 240 kcal caloric restriction (1-2SW, N = 9); and 3-4 sessions/wk without caloric restriction (3-4SW, N = 9). There was a equivalent decrease in the percentage of body fat and total fat mass in both exercise groups compared with that in C. Reduction in SFM was significant in 3-4SW, but not in 1-2SW or C. A negative correlation was observed between training frequency and changes in SFM (r = -0.65). In contrast, VFM decreased significantly and equivalently in both 1-2SW and 3-4SW, but there was no correlation between training frequency and changes in VFM (r = 0.20). It is suggested that the decrease in SFM, but not VFM, is proportional to the amount of aerobic exercise training. A change in VFM appears to be related to an deficit in caloric balance either by dietary restriction (decrease caloric intake) or by increased caloric expenditure.

Abdomen↗

PubMed2006

Potential drug-drug interactions in the outpatient setting.

BACKGROUND: Although medication safety research has tended to focus on inpatients, the safety of drug use among outpatients is also a concern. OBJECTIVE: We estimate the frequency of potentially interacting concomitant medication dispensing among outpatients. RESEARCH DESIGN: We report the number and percent of patients annually dispensed an object drug of interest (ie, warfarin, digoxin, cyclosporine, or lovastatin/simvastatin) with a potentially interacting drug among a random sample of insured adults receiving care from 10 integrated delivery systems. We use 2 definitions of concomitant dispensing: medications dispensed: 1) during the time period for which the patient had the other medication available ('days supply') and 2) on the same day. We also estimate the number of insured U.S. population codispensed these medication pairs. RESULTS: Among patients dispensed a drug of interest, between 17.8% (95% confidence interval [CI]=17.1-18.6%) and 28.0% (95% CI=24.0-32.1%) were concomitantly dispensed a potentially interacting drug using the "days supply" definition, and between 7.1% (95% CI=6.6-7.7%) and 17.7% (95% CI=14.4-21.1%) using the "same day" definition. Extrapolating to the insured U.S. population, between 1.29 (95% CI=1.25-1.33; same day) and 2.67 (95% CI=2.62-2.72; days supply) million insured adults are dispensed 1 of these 4 potentially interacting pairs. CONCLUSIONS: We found evidence of potentially interacting concomitant medication dispensing among outpatients. An opportunity exists to better understand how such dispensing translates into adverse events and ultimately to improved medication safety.

Aged↗

PubMed2004

Ab initio interaction energies of hydrogen-bonded amino acid side chain[bond]nucleic acid base interactions.

Hydrogen-bonding interactions often make substantial contributions to the specificity of protein-nucleic acid complexes. Using a geometric modeling approach, we previously identified 28 possible doubly hydrogen-bonded interactions to the four unpaired RNA bases. Here we present interaction energies of these models, calculated by ab initio quantum chemical methods, and describe a correlation between the computed energies and observed frequencies of the interactions. In general, interactions with charged side chains show the most favorable energies. An Asp/Glu-G interaction may be especially favorable for recognition of unpaired guanines in RNAs. Asn and Ser/Thr/Tyr side chains are calculated to make iso-energetic interactions to the Hoogsteen face of adenine, but Asn-A interactions are much more common with DNA than RNA, and Ser/Thr/Tyr-A interactions are more common with RNA than DNA. Examination of the known interactions suggests that Ser/Thr/Tyr may be accommodated in a wider variety of protein contexts at RNA-protein interfaces. With these calculated intrinsic affinities, it should be possible to better assess the contributions of bidentate hydrogen-bonding interactions to RNA- and DNA-binding specificity.

Adenine↗

PubMed1988

Vocal reaction times to tachistoscopically presented high- and low-frequency verbs: some evidence for selective minor hemisphere linguistic analysis.

The current study investigated the capacity of the right hemisphere to process verbs using a paradigm proven reliable for predicting differential, minor hemisphere lexical analysis in the normal, intact brain. Vocal reaction times of normal subjects were measured to unilaterally presented verbs of high and of low frequency. A significant interaction was noted between the stimulus items and visual fields. Post hoc tests showed that vocal reaction times to verbs of high frequency were significantly faster following right visual-field presentations (right hemisphere). No significant differences in vocal reaction time occurred between the two visual fields for the verbs of low frequency. Also, significant differences were observed between the two types of verbs following left visual-field presentation but not the right. These results were interpreted to suggest that right-hemispheric analysis was restricted to the verbs of high frequency in the presence of a dominant left hemisphere.

Adult↗

PubMed2004

Development of f2/f1 ratio functions in humans.

Otoacoustic emissions (OAEs) presumably represent active processes within the cochlea fundamental to frequency-selectivity in peripheral auditory function. Maturation of the cochlear amplifier, vis-a-vis frequency encoding or selectivity, has yet to be fully characterized in humans. The purpose of this study was to further investigate the maturation of features of the f2/f1 frequency ratio (Distortion Product OAE amplitude X f2/f1 ratio) presumed to reflect cochlear frequency selectivity. A cross-sectional, multivariate study was completed comparing three age groups: pre-term infants, term infants and young adult subjects. Frequency ratio functions were analyzed at three f2 frequencies--2000, 4000 and 6000 Hz. An analysis included an estimation of the optimal ratio (OR) and a bandwidth-like measure (Q3). Analysis revealed significant interactions of age x frequency x gender for optimal ratio and a significant interaction of age x frequency for Q3. Consistent and statistically significant differences for both OR and Q3 were found in female subjects and when f2 = 2 or 6 kHz. This supports research by others [Abdala, J. Acoust. Soc. Am. 114, 3239-3250 (2003)] suggesting that the development of cochlear active mechanisms may still be somewhat in flux at least through term birth. Furthermore, OAEs appear to demonstrate gender differences in the course of such maturational changes.

Adolescent↗

PubMed2002

Cooperative C-H...O hydrogen bonding in CO(2)-Lewis base complexes: implications for solvation in supercritical CO(2).

Understanding the fundamental principles for the design of CO(2)-philic materials is of growing importance due to the potential for enabling "green" chemistry and technologies in liquid and supercritical CO(2) as alternative solvent systems. Recently, there have been numerous efforts to develop hydrocarbon-based CO(2)-philes containing carbonyl groups, which are known to interact through a Lewis acid-Lewis base (LA-LB) interaction with CO(2) molecules, thereby providing the necessary solvation energy for dissolution. In this work, we investigate the role of a weaker, but cooperative, C-H...O hydrogen bond as an additional stabilizing interaction in the solvation of polycarbonyl moieties with hydrogen atoms attached directly to the carbonyl carbon or to the alpha-carbon atom. Ab initio calculations are performed on simple intermolecular complexes of CO(2) with compounds capable of acting as Lewis bases. Systems studied in different interaction configurations include formaldehyde, acetaldehyde, acetic acid, and methyl acetate, as model carbonyl compounds, and dimethyl sulfoxide as a model system for the sulfonyl group. Interaction energies, vibrational frequencies, charge transfer, and other molecular properties are calculated. Results indicate that C-H...O hydrogen bonds may be an important stabilizing interaction that merits consideration in the design of future CO(2)-philes.

Journal Article↗

PubMed2000

Drug-drug interactions in medical patients: effects of in-hospital treatment and relation to multiple drug use.

OBJECTIVES: Adverse drug reactions (ADRs) are a major cause of hospital admissions, thereby leading to significant medical and economical problems. Drug interactions contribute to a major part of ADRs, especially in elderly patients and in patients under polymedication. As a peculiarity of the German health care system the general practitioner is less involved in patient care during hospital stay than in other countries. Consequently, changes in medication at the transition point from out-patient to in-patient care and back may contribute to drug-related problems. PATIENTS: In the present study we investigated potential interactions in 169 consecutive patients with the diagnosis CHD (coronary heart disease) or COLD (chronic obstructive lung disease) who were admitted to the University Hospitals of Hannover and Magdeburg. METHODS: For each patient, potential interactions between prescribed drugs at admission, at discharge, and 3 months after discharge were assessed by using drug interaction data bases. RESULTS: We found that the number of drugs taken per patient as well as the number of interactions per patient are higher during hospitalization than before admission (pre-admission), and fall back after the hospital stay (post-discharge), but not to the pre-admission level. The number of potential interactions was significantly correlated in a polynomial manner to the number of drugs taken by each patient. The number of patients without a potential interaction was 44.4% pre-admission, 39.6% at discharge, and 39.1% post-discharge. Patients with potential interactions had a mean of 2.8, 2.7, and 2.4 interactions at each of the time points. Drug classes mainly involved with potential interactions were kaliuretic diuretics (recorded by 43.3% at discharge), ACE inhibitors (30.3%), anticoagulants and aggregation inhibitors (20.4%) and digitalis glycosides (14.7%). Regarding the frequency of the interaction categories, 68-70% of the potential interactions demand clinical attention, while 1-2% are life-threatening. 17-19% may result in therapeutic benefit; 10-12% are without clinical relevance. CONCLUSIONS: The risk of drug interactions increases exponentially with the number of drugs given to a patient. Although we have no data on the fraction of interactions that became clinically manifest, our study indicates that prescribing fewer drugs can reduce the risk of suffering from sickness secondary to drug interactions. Taking this risk into account may help to improve the quality of drug treatment and to save costs.

Adult↗

PubMedDate not supplied

Hostility, interpersonal interactions, and ambulatory blood pressure.

OBJECTIVE: This study examined aspects of the transactional model of hostility and health by investigating relationships among hostility, interpersonal interactions, and ambulatory blood pressure in a healthy community sample. MATERIALS AND METHODS: Participants included 65 female and 39 male healthy adults between the ages of 18 and 46 years. Ambulatory blood pressure (ABP) and diary data on mood and social interactions were obtained every 20 minutes for 1 day. Mixed models regression analyses were used to evaluate the relationships among hostility, interpersonal interactions, and ABP. RESULTS: Trait hostility was positively associated with the frequency and intensity of negative interactions and was negatively associated with the frequency and intensity of positive interactions. Interacting with others was associated with increases in systolic blood pressure (SBP) and diastolic blood pressure (DBP). The magnitude of the increase in blood pressure was positively associated with the degree to which the interaction was perceived as negative. Hostility was not directly associated with ABP/heart rate (HR) or ABP/HR responses during any interactions or negative interactions. However, there was an interaction between hostility and negative interaction intensity for DBP, suggesting that hostility moderates the effects of negative interactions on DBP. Specifically, increases in the intensity of negative interactions were associated with increases in DBP for participants with high, but not low, hostility. CONCLUSIONS: The results provide partial support for the notion that hostility may be associated with risk for cardiovascular disease through its effects on interpersonal interactions and their cardiovascular correlates.

Adolescent↗

PubMed2002

Effects of testosterone treatment and season on the frequency of dewlap extensions during male-male interactions in the lizard Anolis sagrei.

Lizards of the genus Anolis extend and retract a large and often brightly colored throat fan called a dewlap. The dewlap in most anoles is a sexually dimorphic structure. It is larger in males than females and males use the dewlap more frequently and in more contexts than do females. In the present study we investigated whether plasma testosterone (T) levels and season affect the frequency of dewlap use in male--male interactions in the brown anole, Anolis sagrei. We manipulated plasma T levels by implanting adult, castrated males with pellets that delivered no T, a moderate dose of T, or a high dose of T. In tests with stimulus males, castrated males that were treated with a moderate or with a high dose of T had a significantly higher frequency of dewlap extensions than did castrated males that received no T. However, the frequency of dewlap extensions in castrated males that received the high dose of T did not differ significantly from castrated males that received the moderate dose of T or from non-castrated control males. Males captured during the breeding season and tested in the laboratory had a significantly higher frequency of dewlap extensions than did males captured in the postbreeding season and tested in the same manner. These results suggest that plasma T levels affect how frequently males of A. sagrei extend their dewlaps in male--male interactions and that seasonal changes in male dewlap use may be due to seasonal differences in plasma T levels.

Aggression↗

PubMed1986

Patterns of marital interaction associated with marital dissatisfaction and depression.

This research compared couples reporting high and low levels of marital interactions in which one spouse responds ineffectually to the rights-infringing behavior of the mate. The results of planned comparisons indicated that high frequencies of such interactions were associated with reports of marital dissatisfaction and depression in husbands and marital dissatisfaction in wives. When both spouses described their mates as transgressive and themselves as ineffectual responders to transgression, the dysfunction reported by both spouses was pronounced. Examination of partial correlation, coefficients indicated that each spouse's role in the interaction pattern contributed to its dysfunctional nature.

Depression↗