Significant Interaction (significant + interaction)

Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by Significant Interaction

  • significant interaction effect
  • significant interaction effects

  • Selected Abstracts


    Risk factors for faecal sand excretion in Icelandic horses

    EQUINE VETERINARY JOURNAL, Issue 4 2005
    L. HUSTED
    Summary Reasons for performing study: Sandy soil is often mentioned as a risk factor in the development of sand-related gastrointestinal disease (SGID) in the horse. There are other variables, but few studies confirm any of these. Objective: To investigate soil type, pasture quality, feeding practice in the paddock, age, sex and body condition score as risk factors for sand intake in the horse. Methods: Faeces were collected from 211 Icelandic horses on 19 different studs in Denmark together with soil samples and other potential risk factors. Sand content in faeces determined by a sand sedimentation test was interpreted as evidence of sand intake. Soil types were identified by soil analysis and significance of the data was tested using logistic analysis. Results: Of horses included in the study, 56.4% showed sand in the faeces and 5.7% had more than 5 mm sand as quantified by the rectal sleeve sedimentation test. Soil type had no significant effect when tested as main effect, but there was interaction between soil type and pasture quality. Significant interactions were also found between paddock feeding practice and pasture quality. Conclusion: To evaluate the risk of sand intake it is important to consider 3 variables: soil type, pasture quality and feeding practice. Pasture quality was identified as a risk factor of both short and long grass in combination with sandy soil, while clay soil had the lowest risk in these combinations. Feeding practice in the paddock revealed feeding directly on the ground to be a risk factor when there was short (1,5 cm) or no grass. Also, no feeding outdoors increased the risk on pastures with short grass, while this had no effect in paddocks with no grass. More than 50% of all horses investigated in this study had sand in the faeces. Potential relevance: The identification of risk factors is an important step towards prevention of SGID. Further research is necessary to determine why some horses exhibit more than 5 mm sand in the sedimentation test and whether this is correlated with geophagic behaviour. [source]


    Effects of dietary protein level and cold exposure on tissue responsiveness and sensitivity to insulin in sheep

    JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 11-12 2001
    H. Sano
    The effects of dietary crude protein (CP) level and cold exposure on tissue responsiveness and sensitivity to insulin were studied in sheep. Nine rams were assigned to one of three isoenergetic diets which contained 70, 100, and 140% of CP for maintenance. They were exposed from a thermoneutral environment (20 °C) to a cold environment (0 °C) for 7 days. A hyperinsulinemic euglycemic clamp approach was applied for the determination of tissue responsiveness to insulin (the maximal glucose infusion rate, GIRmax) and tissue sensitivity to insulin (the plasma insulin concentration at half maximal glucose infusion rate, ED50). Dietary CP level influenced digestibilities of dry matter and CP (P=0.002 and P=0.001, respectively), and cold exposure decreased (P=0.01) CP digestibility. The GIRmax and ED50 tended to be influenced (P=0.08) by dietary CP level. The GIRmax was enhanced (P=0.0001) during cold exposure. Significant interactions between diet and environment were found for the GIRmax (P=0.04), but not for ED50 (P=0.07). It is concluded that in sheep dietary CP level can modify insulin action in response to cold exposure. [source]


    Perceived social support from significant others, family and friends and several socio-demographic characteristics

    JOURNAL OF COMMUNITY & APPLIED SOCIAL PSYCHOLOGY, Issue 6 2002
    Miretta Prezza
    Abstract The first aim was to explore the relationship between socio-demographic characteristics and perceived support from significant others, family and friends. Zimet, Dahlem, Zimet, and Farley's Multidimensional Scale of Perceived Social Support (MSPSS) (Journal of Personality Assessment, 52, 1988, 30,41) was administered to 418 males and 623 females between 18 and 77 years of age. The results indicate that family support is higher in males, and the support of friends decreases with age as does the support of significant others. Significant interactions also emerged between gender and age and between gender and marital status. No differences were found for educational level. The second aim was to discover which persons are identified as ,special persons' on the items of the ,Significant others' sub-scale of the MSPSS. Copyright © 2002 John Wiley & Sons, Ltd. [source]


    CONSUMER PREFERENCES FOR VISUALLY PRESENTED MEALS

    JOURNAL OF SENSORY STUDIES, Issue 2 2009
    HANS HENRIK REISFELT
    ABSTRACT The aim of the study was to investigate consumers' preferences for variations of a visually presented meal. The study was conducted in three middle-sized Danish towns, including 768 respondents who were presented with a computerized questionnaire that initially displayed four consecutive series of photos. The series each consisted of eight unique photos of randomized food dishes arranged around the center square in a 3 × 3 array. Five meal components, each with two levels, were investigated. One level of each component was used for each photo, in total 25 = 32 combinations. The respondents were asked to select the meal they preferred the most, the second most and the least, respectively. Significant interactions were found between meal components and background variables such as, gender, age, geographic variables, purchase store and level of education. The current procedure can be applied to help solve a number of problems involving consumer choices. PRACTICAL APPLICATIONS This study outlines an approach to use visual images for investigations of food. Our results suggest that rather complex food stimuli of great similarity can be used to subdivide consumers based on sociodemographic background variables. We present an efficient and cheap quick method that provides and captures more information than an ordinary survey that focuses merely on the most preferred option. As a prerequisite for success, stimuli should be well known and appropriately selected. Hence, the present quick method can easily be applied for several practical purposes, such as pretesting, labeling, product flop prevention, and for specific optimization and selection tasks, e.g., convenience meals and institutional meal services in various contexts. The conjoint layout used allows for late-based segmentation. It further allows for estimation on aggregate as well as individual level. The current approach is useful for database and/or online implementation. [source]


    A Qualitative and Quantitative Approach to Determine the Optimum Combination of Feeding Stimulants for Striped Bass Morone saxatilis Using an Agar Gel Carrier

    JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 1 2002
    Elias Papatryphon
    A series of experiments was conducted to determine the optimum combination of previously identified feeding stimulants (FS), namely L-alanine (Ala), L-serine (Ser), inosine-5,-monophosphate (IMP), and betaine (Bet), for striped bass Morone saxatilis. Three experiments were conducted to determine the optimum combination of FS using an agar gel matrix as a carrier. In the first experiment a 24 factorial experiment was conducted to test all possible combinations of the four FS at two levels, 0 and 0.1 M. Significant interactions between the FS were found, suggesting the complexity of gustatory stimulation and palatability. In the second experiment a 4 × 6 factorial design was employed to test each FS alone and at concentrations ranging from 0 to 8% in order to determine the minimum level at which maximal stimulation is achieved. The results suggest that there is no significant improvement in feed intake beyond the 1 % level of supplementation for all the FS. In addition, Ala produced a significantly greater response compared to all other FS. In the last experiment, a modified single factor method was used to estimate the optimum levels for each FS in a mixture. The range of the concentrations tested was 0,1% of the agar gel for each FS. Combining all four compounds yielded maximal stimulation. The levels of each compound in the final optimum combination of FS were: Ala, 0.4; Ser, 0.6; Bet, 0.4; and IMP, 0.3% of the agar gel. [source]


    DISPOSITIONAL INFLUENCES ON TRANSFER OF LEARNING IN MULTISTAGE TRAINING PROGRAMS

    PERSONNEL PSYCHOLOGY, Issue 4 2002
    DAVID M. HEROLD
    The training effectiveness literature has paid little attention to the potentially dynamic interaction of individual differences with various phases of training in determining ultimate training success. This study investigates the role of individual differences in explaining the transfer of learning from 1 phase of training to another among pilot trainees in a multistage, aviation training program. Using 3 of the Big Five factors (Conscientiousness, Emotional Stability, Openness to Experience), the results showed these measures to contribute to the prediction of the number of hours it took for trainees to attain their private pilot's license. Significant interactions between some of these measures and success on an earlier, simulator phase of the training program were also found. The results are discussed in terms of both the role of individual differences in training research as well as the broader issue of transfer of learning between phases of training. [source]


    Senescence and hyperspectral reflectance of cotton leaves exposed to ultraviolet-B radiation and carbon dioxide

    PHYSIOLOGIA PLANTARUM, Issue 2 2004
    Vijaya Gopal Kakani
    The objectives of this study were to determine the effects of UV-B radiation and atmospheric carbon dioxide concentrations ([CO2]) on leaf senescence of cotton by measuring leaf photosynthesis and chlorophyll content and to identify changes in leaf hyperspectral reflectance occurring due to senescence and UV-B radiation. Plants were grown in controlled-environment growth chambers at two [CO2] (360 and 720 µmol mol,1) and three levels of UV-B radiation (0, 7.7 and 15.1 kJ m,2 day,1). Photosynthesis, chlorophyll, carotenoids and phenolic compounds along with leaf hyperspectral reflectance were measured on three leaves aged 12, 21 and 30 days in each of the treatments. No interaction was detected between [CO2] and UV-B for any of the measured parameters. Significant interactions were observed between UV-B and leaf age for photosynthesis and stomatal conductance. Elevated [CO2] enhanced leaf photosynthesis by 32%. On exposure to 0, 7.7 and 15.1 kJ of UV-B, the photosynthetic rates of 30-day-old leaves compared with 12-day-old leaves were reduced by 52, 76 and 86%, respectively. Chlorophyll pigments were not affected by leaf age at UV-B radiation of 0 and 7.7 kJ, but UV-B of 15.1 kJ reduced the chlorophylls by 20, 60 and 80% in 12, 21 and 30-day-old leaves, respectively. The hyperspectral reflectance between 726 and 1142 nm showed interaction for UV-B radiation and leaf age. In cotton, leaf photosynthesis can be used as an indicator of leaf senescence, as it is more sensitive than photosynthetic pigments on exposure to UV-B radiation. This study revealed that, cotton leaves senesced early on exposure to UV-B radiation as indicated by leaf photosynthesis, and leaf hyperspectral reflectance can be used to detect changes caused by UV-B and leaf ageing. [source]


    Predictive Validity of a Computerized Emergency Triage Tool

    ACADEMIC EMERGENCY MEDICINE, Issue 1 2007
    Sandy L. Dong MD
    Abstract Background Emergency department (ED) triage prioritizes patients on the basis of the urgency of need for care. eTRIAGE is a Web-based triage decision support tool that is based on the Canadian Triage and Acuity Scale (CTAS), a five level triage system (CTAS 1 = resuscitation, CTAS 5 = nonurgent). Objectives To examine the validity of eTRIAGE on the basis of resource utilization and cost as measures of acuity. Methods Scores on the CTAS, specialist consultations, computed-tomography use, ED length of stay, ED disposition, and estimated ED and hospital costs (if the patient was subsequently admitted to hospital) were collected for each patient over a six month period. These data were queried from a database that captures all regional ED visits. Correlations between CTAS score and each outcome were measured by using logistic regression models (categorical variables), univariate analysis of variance (continuous variables), and the Kruskal-Wallis analysis of variance (costs). A multivariate regression model that used cost as the outcome was used to identify interaction between the variables presented. Results Over the six month study, 29,524 patients were triaged by using eTRIAGE. When compared with CTAS level 3, the odds ratios for consultation, CT scan, and admission were significantly higher in CTAS 1 and 2 and were significantly lower in CTAS 4 and 5 (p < 0.001). When compared with CTAS levels 2,5 combined, the odds ratio for death in CTAS 1 was 664.18 (p < 0.001). The length of stay also demonstrated significant correlation with CTAS score (p < 0.001). Costs to the ED and hospital also correlated significantly with increasing acuity (median costs for CTAS levels in Canadian dollars: CTAS 1 =$2,690, CTAS 2 =$433, CTAS 3 =$288, CTAS 4 =$164, CTAS 5 =$139, and p < 0.001). Significant interactions between the data collected were found in a multivariate regression model, although CTAS score remained highly associated with costs. Conclusions Acuity measured by eTRIAGE demonstrates excellent predictive validity for resource utilization and ED and hospital costs. Future research should focus on specific presenting complaints and targeted resources to more accurately assess eTRIAGE validity. [source]


    Maternally separated rats show deficits in maternal care in adulthood

    DEVELOPMENTAL PSYCHOBIOLOGY, Issue 1 2001
    Vedran Lovic
    Abstract Although there is considerable research on the phenomenology, neuroendocrinology, neuroanatomy, and sensory control of maternal behavior, little is known about the influences of early postnatal and postweaning experiences on the development of maternal behavior. The purpose of this study was to assess how early life separation from the mother rat affects development of the offspring's juvenile and adult maternal behavior. From postnatal Days 1 to 17, 3 female rats within each litter were separated (SEP) from the mother and the rest of the litter for 5 hr daily while 3 of their sisters were not maternally separated (NSEP). On postnatal Day 21, all subjects were weaned and randomly assigned to one of three juvenile conditions. One female from both SEP and NSEP groups was either isolated (I), given a social conspecific (S), or given 1- to 4-day-old pups (P) for 5 consecutive days. Maternal behavior of SEP and NSEP animals was assessed and recorded on each of the 5 days. Once all animals reached adulthood, they were mated, gave birth, and were assessed for their maternal behavior. We found that the effects of maternal separation on juvenile maternal-like behaviors were minimal. On the other hand, maternal separation reduced adult maternal licking and crouching over pups. In addition, there was a significant interaction between postnatal and juvenile experience on maternal crouching in maternal animals. These results are discussed in terms of the variety of possible behavioral, endocrine, and neurochemical mechanisms that mediate the effects of early life experiences on adult maternal behavior. © 2001 John Wiley & Sons, Inc. Dev Psychobiol 39: 19,33, 2001 [source]


    Treatment process, alliance and outcome in brief versus extended treatments for marijuana dependence

    ADDICTION, Issue 10 2010
    Carly J. Gibbons
    ABSTRACT Aims The Marijuana Treatment Project, a large multi-site randomized clinical trial, compared a delayed treatment control condition with a brief (two-session) and extended (nine-session) multi-component treatment among 450 marijuana-dependent participants. In this report we present treatment process data, including the fidelity of treatment delivery in the three community-based treatment settings as well as the relationships between treatment process and outcome. Design Independent evaluations of clinician adherence and competence ratings were made based on 633 videotaped sessions from 163 participants. Relationships between clinician adherence and competence, ratings of the working alliance and marijuana treatment outcomes were evaluated. Findings Protocol treatments were implemented with strong fidelity to manual specifications and with few significant differences in adherence and competence ratings across sites. In the brief two-session treatment condition, only the working alliance was associated significantly with frequency of marijuana use, but in the extended treatment therapist ratings of working alliance predicted outcomes, as did the interaction of alliance and curvilinear adherence. Conclusions Behavioral treatments for marijuana use were delivered in community settings with good fidelity. Participant and therapist working alliance scores were associated significantly with improved marijuana use outcomes in a brief behavioral treatment for adults with marijuana dependence. In extended treatment the therapist ratings of working alliance were associated with more positive outcome. However, in that treatment there was also a significant interaction between alliance and curvilinear adherence. [source]


    Is natural selection a plausible explanation for the distribution of Idh- 1 alleles in the cricket Allonemobius socius?

    ECOLOGICAL ENTOMOLOGY, Issue 1 2006
    Diana L. Huestis
    Abstract., 1.,Allozyme alleles in natural populations have been proposed as either neutral markers of genetic diversity or the product of natural selection on enzyme function, as amino acid substitutions that change electrophoretic mobility may also alter enzyme performance. To address these possibilities, researchers have used both correlative analyses and empirical studies. 2.,Here, geographically structured variation of the enzyme isocitrate dehydrogenase (Idh- 1) in the striped ground cricket Allonemobius socius Scudder (Orthoptera: Gryllidae) is examined. The distributions of Idh- 1 alleles appear to be related to environmental gradients, as allele frequencies showed significant relationships with mean annual temperature and precipitation. Specifically, the slowest mobility allele was more frequent at colder temperatures, while the converse occurred for the fastest mobility allele. 3.,An exploratory experiment was performed to examine fitness effects of possessing different Idh- 1 alleles at two temperatures to test the hypothesis that the geographic structure of this locus may reflect environmental adaptation. Results showed that a significant interaction between temperature and Idh- 1 genotype affected the number of eggs laid, with success of homozygous individuals matching environmental expectations. 4.,The above results show that (1) variation in the frequency of Idh- 1 alleles is significantly related to environmental gradients in the eastern U.S.A. and (2) alternative alleles of Idh- 1 appear to influence the egg-laying ability of individuals differently depending on environmental temperature. Together, these results suggest that natural selection is a plausible mechanism underlying the distribution of Idh- 1 alleles in this species, although more detailed studies are needed. [source]


    ADH1B*2 allele is protective against alcoholism but not chronic liver disease in the Hungarian population

    ADDICTION, Issue 5 2010
    Reka Toth
    ABSTRACT Background Standardized death rates from chronic liver diseases (CLDs) in Hungary are much higher than the European Union average. Carrying the alcohol dehydrogenase 1B 48His allele (rs1229984 or ADH1B*2) could decrease the risk of alcoholism, but with persistent drinking may confer a greater risk of CLDs. The aim of this study was to assess the prevalence of this polymorphism in the Hungarian population and its association with alcohol consumption and with CLDs. Methods and results A total of 278 cases with diagnosed CLDs and 752 controls without any alterations in liver function, all males aged 45,64, were screened for ADH1B Arg48His polymorphism. ADH1B*2 allele frequencies in controls and cases were 8.31% and 4.50%, respectively (,2 = 9.2; P = 0.01). Carrying the ADH1B*2 allele was associated with significantly lower odds ratio (OR) for drinking frequency (OR = 0.63; P = 0.003), the number of positive answers on CAGE (Cut-down, Annoyed, Guilt, Eye-opener) assessment (OR = 0.58; P = 0.005) and a positive CAGE status (OR = 0.55; P = 0.007). There was a significant association between ADH1B*2 and CLDs (OR = 0.50; P = 0.003), but it disappeared after adjusting for CAGE status and scores (OR = 0.67 P = 0.134; OR = 0.67 P = 0.148, respectively) and weakened after adjusting for drinking frequency (OR = 0.61; P = 0.045). Among heavy drinkers the presence of ADH1B*2 did not increase the risk of cirrhosis but there was a significant interaction between genotype and CAGE status (P = 0.003, P = 0.042), with ADH1B*2 conferring reduced risk of CLDs in CAGE negatives. Conclusion In Hungarians, the ADH1B 48His allele reduces the risk of alcoholism, but not the risk of chronic liver disease among heavy drinkers. [source]


    Effects of hunger level and nutrient balance on survival and acetylcholinesterase activity of dimethoate exposed wolf spiders

    ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2002
    Lars-Flemming Pedersen
    Abstract The influence of two nutritional factors (food quantity and quality) on the responses of a wolf spider, Pardosa prativaga (L.K.), to a high dose of the insecticide dimethoate, was investigated in a fully factorial experimental design. Spider groups with different (good and bad) nutrient balance were created by feeding them fruit flies of either high or low nutrient content for 28 days. Both groups were then split into satiated and 14 days starved subgroups. Each of these was further divided into insecticide treated and control halves. Survivorship and acetylcholinesterase (AChE) activity measured on the survivors were used as response variables. Survivorship after topical dimethoate exposure (LD50; 48 h) was influenced by spider body weight, nutrient balance, and starvation. Furthermore, AChE activity was significantly inhibited by dimethoate exposure. A significant interaction between nutrient balance, starvation, and dimethoate exposure revealed synergistic effects of starvation and nutrient imbalance on AChE inhibition by dimethoate in surviving spiders. These results show that the tolerance of non-target arthropods to dimethoate may vary depending on the nutritional history of the animal. [source]


    Gender differences in genetic damage induced by the tobacco-specific nitrosamine NNK and the influence of the Thr241Met polymorphism in the XRCC3 gene

    ENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 1 2005
    Courtney E. Hill
    Abstract The rapid increase in adenocarcinoma of the lung and mortality amongst women strongly suggests that gender differences exist in sensitivity to certain tobacco carcinogens. In the current study, we performed the mutagen-sensitivity assay, with the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), to test the hypothesis that women are more sensitive to the genotoxic effects of NNK than men. Chromosome aberration (CA) frequencies in peripheral blood lymphocytes (PBLs) from 99 patients were evaluated before and after in vitro exposure to NNK. Because the Thr241Met polymorphism in the DNA-repair gene XRCC3 is associated with increased risk of tobacco-related cancers, especially among women, we also tested the hypothesis that individuals who inherit the homozygous variant 241Met allele are more sensitive to the genotoxic effects of NNK. CA frequency was significantly higher 1 hr after NNK treatment in women, compared with men (P = 0.02). When smoking and gender were considered together, a significant interaction was observed. PBLs from female smokers had significantly higher frequencies of NNK-induced CA, compared with female nonsmokers 1 hr after treatment (P = 0.02). We observed no overall effect of the Thr241Met polymorphism on NNK-induced CA in men, women, smokers, or nonsmokers. Overall, our data indicate that women are more sensitive to the genotoxic effects of NNK than men. Because in past years smoking among women has increased, and in view of the close correlation between NNK exposure and adenocarcinoma of the lung, our data provide a plausible explanation for the recent increase in the incidence of this cancer among women. Environ. Mol. Mutagen., 2005. © 2005 Wiley-Liss, Inc. [source]


    Influence of contamination by organochlorine pesticides and polychlorinated biphenyls on the breeding of the Spanish Imperial Eagle (Aquila adalberti)

    ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2008
    Mauro Hernández
    Abstract We evaluated temporal and regional trends of organochlorine (OC) pesticide (including polychlorinated biphenyl [PCB]) levels in eggs of the Spanish Imperial Eagle (Aquila adalberti) collected in Spain between 1972 and 2003. Levels of p,p,-dichlorodiphenyldichloroethylene (DDE) and PCBs varied significantly (p = 0.022) among regions (central, western, and Doñana), being higher in Doñana than in the central and western populations (DDE: 1.64 ± 5.56, 0.816 ± 1.70, and 1.1 ± 2.66 ,g/g, respectively; PCBs: 1.189 ± 5.0, 0.517 ± 1.55, and 0.578 ± 1.75 ,g/g, respectively). Levels of DDE decreased with time, but a significant interaction was observed between region and time. In Doñana, egg volume and breadth as well as Ratcliffe Index were significantly lower after DDT use (p = 0.0018) than during the pre-DDT period (p = 0.0018); eggs were significantly smaller overall than in the other two regions (p = 0.04) and were smaller when DDE levels increased, even when controlling for regional differences (p = 0.04). Productivity in Doñana was significantly lower than in the other regions (p < 0.001). Clutch size in Doñana varied according to DDE concentrations (p = 0.01), with the highest DDE concentrations found in clutches consisting of one egg. When considering eggs with DDE levels greater than 3.5 ,g/g, a significant effect of DDE on fertility was found (p = 0.03). Clutches with DDE levels greater than 4.0 ,g/g had a higher probability of hatching failure (p = 0.07) and produced fewer fledglings (p = 0.03). If we consider 3.5 ,g/g as the lowest-observable-adverse-effect level, the proportion of sampled clutches that exceeded that level in Doñana (29%) was significantly higher than in other regions (p < 0.001). These eggs showed a mean percentage of thinning of 16.72%. Contamination by OCs, mainly DDE, could explain, at least in part, the low productivity of the Spanish Imperial Eagles in Doñana. [source]


    Effect of magnitude and direction of force on laryngeal abduction: Implications for the nerve-muscle pedicle graft technique

    EQUINE VETERINARY JOURNAL, Issue 4 2009
    P. CRAMP
    Summary Reasons for performing study: The nerve-muscle pedicle graft technique is a treatment for recurrent laryngeal neuropathy (RLN), but the optimal placement of the pedicles within the cricoarytenoideus dorsalis (CAD) muscle is unknown. Hypothesis: The magnitude and direction of force placed on the muscular process of the left arytenoid cartilage affects the magnitude of laryngeal abduction. Methods: Five larynges were harvested from cadavers. Using increments of 0.98 N, a dead-weight force generator applied a force of 0,14.7 N for 1 min each to the left muscular process at 0, 10, 20, 30, 40, 50, 60 and 70° angles. The rima glottis was photographed digitally 1 min after each force had been applied. Distances between biomarkers (Lines 1,4) and right to left angle quotient (RLQ) were used to assess the degree of left arytenoid abduction. Results: Increasing force from 0,14.7 N progressively and significantly increased the length of all lines and RLQ, indicating abduction. Furthermore, there was a significant interaction between force and angles. Applying forces of 7.84 N or greater (Lines 2,4 and RLQ) or 11.76 N or greater (Line 1) at angles 0, 10, 20 and 30° resulted in significantly greater abduction than applying the same forces at 40, 50, 60 and 70°. Angles of 0,30° correspond with the direction of pull exerted by the lateral compartment of the CAD muscle. Conclusion: In RLN, nerve-muscle pedicle grafts should be placed preferentially in the lateral rather than in the medial compartment of the CAD muscle. Potential relevance: The information presented can be used to assist surgeons in the planning and application of the nerve-muscle pedicle graft procedure. [source]


    Defence of Females by Dominant Males of Artibeus jamaicensis (Chiroptera: Phyllostomidae)

    ETHOLOGY, Issue 5 2000
    Jorge Ortega
    Defence of females by dominant males of the Jamaican fruit-eating bat Artibeus jamaicensis was observed in two natural colonies over 2 yr. A log-linear model was used to evaluate the frequency distribution of visits to harems by sex, season and agonistic interaction of dominant males. Harem group size varied from four to 18 females, with one adult male in the small and medium-sized groups and two males in the large groups (> 14 females). A highly significant interaction was noted between the age and sex of the visitor and the response of the dominant male. Male visitors were attacked more often than female and juvenile visitors. Aggressive defence increased during the reproductive seasons, with dominant males showing more agonistic responses towards male visitors. An increase in the frequency of visits by male visitors was noted in harem groups that ranged in size from four to 12 females, but the frequency of male visits declined in harem groups that contained more than 14 females. [source]


    Glutathione, vitamin E and oxidative stress in coronary artery disease: relevance of age and gender

    EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 4 2009
    V. Cavalca
    Abstract Background, Observational studies suggest that low levels of antioxidants are associated with high risk for coronary artery disease (CAD). We investigated whether the biomarkers of oxidative balance undergo the same modifications in all CAD patient groups, regardless of gender and age. Materials and methods, One hundred sixty-eight CAD patients and 107 healthy controls were assayed for plasma levels of reduced glutathione (GSH), ,- and ,-tocopherol (,- and ,-T) as endogenous antioxidants. A damage score (DS), representative of oxidative stress status, was calculated. ancova models were used to test the association between antioxidants, DS and CAD and its modulation by age and gender. Results, The DS was higher in CAD than in controls. GSH levels, were lower in CAD patients (mean ± SEM: 57·61 ± 1·87 ,mol 10 g,1 haemoglobin vs. 68·55 ± 2·23 in controls, P < 0·0006) in males and in older subjects. Levels of other antioxidants exhibited a complex pattern. Overall, no difference was found in ,- and ,-T contents between CAD and controls, but lower ,-T values were observed in CAD females. A significant interaction between CAD status and gender was observed (P = 0·003). Conclusions, Our study shows that the involvement of antioxidants in CAD is related to patients' characteristics. These findings may be relevant in planning antioxidant therapies. [source]


    HUMAN STUDY: Preconscious attentional bias in cigarette smokers: a probe into awareness modulation on attentional bias

    ADDICTION BIOLOGY, Issue 4 2009
    Xiaodan Yan
    ABSTRACT It has been frequently reported that smokers showed attentional bias toward smoking-related stimuli. The current study aimed to examine whether such bias was also present when subjects were unaware of the presented stimuli and the possible role of awareness modulation on attentional bias. With a psychophysical approach (interocular suppression), we suppressed subjects' awareness to the cigarette pictures presented to one of their eyes. The visual dot probe task was modified to increase the perceptual load and to control the physical features between two rivaling images. Twenty-eight male smokers and 25 male non-smokers participated in the experiment. We found a significant interaction between experiment conditions and subject groups, with only the smoker group showed attentional bias toward cigarette pictures in unaware condition. Moreover, smokers' attentional bias in unaware condition was negatively correlated with their scores on Cigarette Dependence Scale while their attentional bias in aware condition was positively correlated with scores on Questionnaires of Smoking Urges. Such dissociation indicates the possibility of awareness modulation on attentional bias: it is possible that in aware condition, the attentional bias was modulated by smoking urge in awareness, thus concealed the effect of dependence degree. Further studies indicated that awareness modulated attentional bias through many factors, such as craving, quit attempt, attitude and disgust. Interestingly, non-smokers also showed attentional bias in aware condition, which further suggested that due to awareness modulation, attentional bias could even be addiction-unrelated. [source]


    Side-to-side differences in pressure pain thresholds and pericranial muscle tenderness in strictly unilateral migraine

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 2 2008
    C. Fernández-de-las-Peñas
    Previous studies dealing with pressure pain sensitivity or muscle tenderness in migraine have shown conflicting results. Our aim was to explore the differences in mechanical pain sensitivity and pericranial muscle tenderness between patients with unilateral migraine and healthy controls, and to analyse side-to-side differences in both study groups. Pressure pain thresholds (PPT) at cephalic and neck points, plus local and total tenderness scores were blindly assessed in 25 patients with strictly unilateral migraine and 25 healthy subjects. For PPT in the neck there were significant differences between groups (F = 47.029; P < 0.001) and sides (F = 6.363; P < 0.01), and a significant interaction between group and side (F = 5.201; P = 0.02), while PPT in the cephalic point showed differences between groups (F = 11.774; P < 0.001), but not sides (F = 2.838; P = 0.1). The total tenderness score showed significant differences between groups (F = 6.800; P < 0.01) and sides (F = 17.699; P < 0.001), along with a significant interaction between group and side (F = 14.420; P < 0.001). Patients had lower PPT and increased pericranial tenderness on the symptomatic side as compared with the non-symptomatic side and to either side in controls (P < 0.001), whereas no significant differences were identified between the non-symptomatic side and controls (P > 0.9). In migraine patients, PPT levels and muscle tenderness scores were negatively correlated (P < 0.001). The enhancement of local tenderness scores was related to hyperesthesia of specific muscles (sternocleidomastoid, suboccipital, and temporalis) rather than a generalized pericranial tenderness. Future studies should investigate the neuro-physiological basis for the laterality of allodynic and hyperalgesic responses in unilateral migraine. [source]


    Group motives in threatening contexts: When a loyalty conflict paradoxically reduces the influence of an anti-discrimination ingroup norm

    EUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 2 2009
    Juan M. Falomir-Pichastor
    The influence of pro- versus anti-discrimination ingroup norms on Swiss nationals' attitudes towards foreigners was investigated as a function of national identification and perceived material ingroup threat. As predicted, results revealed a significant interaction between identification and threat: High identifiers showed a more negative attitude than low identifiers mainly when perceived threat was high. In other words, high identifiers conformed to the pro-discrimination norm, but showed a counter-conformity effect for the anti-discrimination norm. Additional results revealed that high identifiers actually disagreed with the anti-discrimination norm when perceived threat was high, but that they were more attached to the ingroup. These findings suggest that when the ingroup norm is not an appropriate response to an ingroup threat (i.e. anti-discrimination norm), high identifiers find themselves in a loyalty conflict: they are unable to simultaneously conform to the group norm and protect the group. This conflict was resolved through a compensatory mechanism: High identifiers distanced themselves from the ingroup norm in order to protect the group (i.e. by increasing negative attitudes towards foreigners) but reinforced other ingroup ties (i.e. by increasing attachment to the ingroup values). Copyright © 2008 John Wiley & Sons, Ltd. [source]


    THE CONTRIBUTION OF SPONTANEOUS MUTATION TO VARIATION IN ENVIRONMENTAL RESPONSES OF ARABIDOPSIS THALIANA: RESPONSES TO LIGHT

    EVOLUTION, Issue 2 2005
    Christina M. Kavanaugh
    Abstract It has been hypothesized that new, spontaneous mutations tend to reduce fitness more severely in more stressful environments. To address this hypothesis, we grew plants representing 20 Arabidopsis thaliana mutationaccumulation (M-A) lines, advanced to generation 17, and their progenitor, in differing light conditions. The experiment was conducted in a greenhouse, and two treatments were used: full sun and shade, in which influx of red light was reduced relative to far-red. The shade treatment was considered the more stressful because mean absolute fitness was lower in that treatment, though not significantly so. Plants from generation 17 of M-A developed significantly faster than those from generation 0 in both treatments. A significant interaction between generation and treatment revealed that, counter to the hypothesis, M-A lines tended to have higher fitness on average relative to the progenitor in the shaded conditions, whereas, in full sun, the two generations were similar in fitness. A secondary objective of this experiment was to characterize the contribution of new mutations to genotype x environment interaction. We did not, however, detect a significant interaction between M-A line and treatment. Plots of the line-specific enviromental responses indicate no tendency of new mutations to contribute to fitness trade-offs between environments. They also do not support a model of conditionally deleterious mutation, in which a mutatn reduces fitness only in a particular environment. These results suggest that interactions between genotype and light environment previously documented for A. thaliana are not explicable primarily as a consequence of steady input of spontaneous mutations having environment-specific effects. [source]


    GENETIC VARIATION IN MALE EFFECTS ON FEMALE REPRODUCTION AND THE GENETIC COVARIANCE BETWEEN THE SEXES

    EVOLUTION, Issue 6 2003
    MARY ELLEN CZESAK
    Abstract., Males of many insect species increase the fecundity and/or egg size of their mates through the amount or composition of their nuptial gifts or ejaculate. The genetic bases of such male effects on fecundity or egg size are generally unknown, and thus their ability to evolve remains speculative. Likewise, the genetic relationship between male and female investment into reproduction in dioecious species, which is expected to be positive if effects on fecundity are controlled by at least some of the same genes in males and females, is also unknown. Males of the seed beetle Stator limbatus contribute large ejaculates to females during mating, and the amount of donated ejaculate is positively correlated with male body mass. Females mated to large males lay more eggs in their lifetime than females mated to small males. We describe an experiment in which we quantify genetic variation in the number of eggs sired by males (mated to a single female) and found that a significant proportion of the phenotypic variance in the number of eggs sired by males was explained by their genotype. Additionally, the number of eggs sired by a male was highly positively genetically correlated with his body mass. The between-sex genetic correlation, that is, the genetic correlation between the number of eggs sired by males and the number of eggs laid by females, was highly positive when eggs were laid on Acacia greggii seeds. This indicates that males that sire many eggs have sisters that lay many eggs. Thus, some of the genes that control male ejaculate size (or some other fecundity-enhancing factor) when expressed in males appear to control fecundity when expressed in females. We found no significant interaction between male and female genotype on fecundity. [source]


    Tissue-specific regulation of ACE/ACE2 and AT1/AT2 receptor gene expression by oestrogen in apolipoprotein E/oestrogen receptor-, knock-out mice

    EXPERIMENTAL PHYSIOLOGY, Issue 5 2008
    K. Bridget Brosnihan
    Angiotensin-converting enzyme (ACE) and ACE2 and the AT1 and AT2 receptors are pivotal points of regulation in the renin,angiotensin system. ACE and ACE2 are key enzymes in the formation and degradation of angiotensin II (Ang II) and angiotensin-(1,7)(Ang-(1,7)). Ang II acts at either the AT1 or the AT2 receptor to mediate opposing actions of vasoconstriction or vasodilatation respectively. While it is known that oestrogen acts to downregulate ACE and the AT1 receptor, its regulation of ACE2 and the AT2 receptor and the involvement of a specific oestrogen receptor subtype are unknown. To investigate the role of oestrogen receptor-, (ER,) in the regulation by oestrogen of ACE/ACE2 and AT1/AT2 mRNAs in lung and kidney, ovariectomized female mice lacking apolipoprotein E (ee) with the ER, (AAee) or without the ER, (,,ee) were treated with 17,-oestradiol (6 ,g day,1) or placebo for 3 months. ACE, ACE2, AT1 receptor and AT2 receptor mRNAs were measured using reverse transcriptase, real-time polymerase chain reaction. In the kidney, 17,-oestradiol showed 1.7-fold downregulation of ACE mRNA in AAee mice, with 2.1-fold upregulation of ACE mRNA in ,,ee mice. 17,-Oestradiol showed 1.5- and 1.8-fold downregulation of ACE2 and AT1 receptor mRNA in AAee mice; this regulation was lost in ,,ee mice. 17,-Oestradiol showed marked (81-fold) upregulation of the AT2 receptor mRNA in AAee mice. In the lung, 17,-oestradiol treatment had no effect on AT1 receptor mRNA in AAee mice, but resulted in a 1.5-fold decreased regulation of AT1 mRNA in ,,ee mice. There was no significant interaction of oestrogen with ER, in the lung for ACE, ACE2 and AT2 receptor genes. These studies reveal tissue-specific regulation by 17,-oestradiol of ACE/ACE2 and AT1/AT2 receptor genes, with the ER, receptor being primarily responsible for the regulation of kidney ACE2, AT1 receptor and AT2 receptor genes. [source]


    Angiotensin-Converting Enzyme Genotype Affects the Response of Human Skeletal Muscle to Functional Overload

    EXPERIMENTAL PHYSIOLOGY, Issue 5 2000
    Jonathan Folland
    The response to strength training varies widely between individuals and is considerably influenced by genetic variables, which until now, have remained unidentified. The deletion (D), rather than the insertion (I), variant of the human angiotensin-converting enzyme (ACE) genotype is an important factor in the hypertrophic response of cardiac muscle to exercise and could also be involved in skeletal muscle hypertrophy , an important factor in the response to functional overload. Subjects were 33 healthy male volunteers with no experience of strength training. We examined the effect of ACE genotype upon changes in strength of quadriceps muscles in response to 9 weeks of specific strength training (isometric or dynamic). There was a significant interaction between ACE genotype and isometric training with greater strength gains shown by subjects with the D allele (mean ± S.E.M.: II, 9.0 ± 1.7%; ID, 17.6 ± 2.2%; DD, 14.9 ± 1.3%, ANOVA, P 0.05). A consistent genotype and training interaction (ID DD II) was observed across all of the strength measures, and both types of training. ACE genotype is the first genetic factor to be identified in the response of skeletal muscle to strength training. The association of the ACE I/D polymorphism with the responses of cardiac and skeletal muscle to functional overload indicates that they may share a common mechanism. These findings suggest a novel mechanism, involving the renin-angiotensin system, in the response of skeletal muscle to functional overload and may have implications for the management of conditions such as muscle wasting disorders, prolonged bed rest, ageing and rehabilitation, where muscle weakness may limit function. [source]


    TRB3, upregulated by ox-LDL, mediates human monocyte-derived macrophage apoptosis

    FEBS JOURNAL, Issue 10 2009
    Yuan-yuan Shang
    Tribble3 (TRB3), a mammalian homolog of Drosophila tribbles, slows cell-cycle progression, and its expression is increased in response to various stresses. The aim of this study was to investigate the role of the TRB3 gene in macrophage apoptosis induced by oxidized low-density lipoprotein (ox-LDL). We found that, in human monocyte-derived macrophages, TRB3 is upregulated by ox-LDL in a dose- and time-dependent manner. The cell viability of TRB3-overexpressing macrophages was decreased, but apoptosis was increased and the level of activated caspase-3 increased. Factorial analyses revealed no significant interaction between TRB3 overexpression and ox-LDL stimulation with respect to macrophage apoptosis. Furthermore, TRB3-silenced macrophages showed decreased apoptosis, and TRB3-silenced cells treated with ox-LDL showed significantly increased apoptosis. Silencing of TRB3 and ox-LDL stimulation showed significant interaction for macrophage apoptosis, suggesting that TRB3 knockdown resisted the macrophage apoptosis induced by ox-LDL. Therefore, TRB3 in part mediates the macrophage apoptosis induced by ox-LDL, which suggests that TRB3 might be involved in vulnerable atherosclerotic plaque progression. [source]


    Body size, locomotor speed and antipredator behaviour in a tropical snake (Tropidonophis mairii, Colubridae): the influence of incubation environments and genetic factors

    FUNCTIONAL ECOLOGY, Issue 5 2001
    J. K. Webb
    Summary 1,The physical conditions experienced by reptile embryos inside natural nests can influence the size, shape and behaviour of the resultant hatchlings. Although most reptiles are tropical, the effects of incubation temperatures on offspring phenotypes have received little attention in tropical species. 2,The consequences of differences in thermal variance during incubation on offspring were studied in a tropical natricine snake (the Keelback Tropidonophismairii), which lays eggs in soil cracks of varying depths. Some 253 eggs from 19 clutches were incubated under two thermal regimes with identical mean temperatures (25·6 °C), but temperatures in the ,variable' treatment fluctuated more (21·8,29·6 °C) than those in the ,constant' temperature treatment (25·2,26·5 °C). These thermal regimes were similar to those of shallow (20 cm deep) and deep (40 cm deep) soil cracks, respectively, and represent thermal conditions inside natural nests and potential nest sites. 3,Incubation temperatures affected body size, shape and antipredator behaviour of hatchling snakes. Snakes from constant temperature incubation were longer and thinner than snakes from high variance incubation. Clutch effects influenced all offspring traits, with significant interactions between clutch of origin and incubation treatment for body size, but not swimming speed or behaviour. 4,There was a significant interaction between incubation treatment and offspring sex on neonate swimming speed. Incubation under cycling thermal regimes significantly increased swimming speeds of females, but had little effect on males. Such sex differences in phenotypic responses of hatchling snakes support a major assumption of the Charnov,Bull hypothesis for the evolution of temperature-dependent sex determination. [source]


    Maintenance of the alcohol dehydrogenase polymorphism in Tiger Salamanders, II.

    FUNCTIONAL ECOLOGY, Issue 1 2000
    Differences in biochemical function among allozymes
    Abstract 1.,Previous studies of Tiger Salamanders demonstrated that variation in alcohol dehydrogenase (Adh) contributed significantly to associations between multilocus heterozygosity and oxygen consumption traits, and that Adh variation was associated with levels of pond-oxygen and metamorphic ability in extreme oxygen environments. Here Adh allozymes are characterized kinetically, and relationships between Adh and oxygen-related physiological traits (ATP/Hb, 2,3-DPG/Hb) are measured. 2.,Kinetic differences were measured among Adh allozymes in the acetaldehyde-to-ethanol direction: kcat/Km ratios (the catalytic constant divided by the Michaelis,Menton constant) were significantly higher in Adh-SF than the other two genotypes, and in Adh-SS compared with Adh-FF. No significant differences were measured in the ethanol to acetaldehyde direction. 3.,Adh-SS had a significantly higher ATP/Hb than Adh-FF, with the Adh-SF intermediate. In addition, a significant interaction between Hb and body mass was measured, such that Adh-FF showed a negative relationship between Hb concentration and body mass while the other two genotypes showed a positive relationship. 4.,These results are consistent with the hypothesis that variation at the Adh locus has adaptive and physiological significance, and that functional differences among Adh allozymes partly explain significant associations between multilocus genotype and organismal traits. [source]


    Improvement of the comprehension of written information given to healthy volunteers in biomedical research: a single-blind randomized controlled study

    FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 2 2007
    Adeline Paris
    Abstract Writing an informed consent form (ICF) for biomedical research is a difficult task. We conducted a multicenter single-blind randomized controlled trial to identify whether a working group or the systematic improvement in lexico-syntactic readability or an association of the two could increase the comprehension of the written information given to healthy volunteers enrolled in biomedical research. Participants were randomized to read one of four versions of the ICF: unchanged ICF (A), ICF with systematic lexico-syntactic readability improvement (B), ICF modified by a working group (C), and ICF modified by the working group followed by systematic lexico-syntactic improvement (D). The primary end-point was the objective comprehension score at day 0 for each study group. The scores of objective comprehension at day 0 were statistically different between the four study groups (anovaP = 0.020). The pairwise analysis showed an improvement in the working group vs. the unchanged group (P = 0.003), and a tendency to improvement in the group who read the ICF modified using lexico-syntactic readability and in the group who read the ICF modified using the two methods (P = 0.020 and 0.027 respectively). We conducted a two-way anova to identify some characteristics of the population which could explain this score. There was a significant interaction between the type of informed consent document (ICD) and the gender. Improving the ICD in phase I biomedical research leads to better comprehension, whether the method used is systematic lexico-syntactic improvement or a review by a working group. The improvement is specifically observed in men compared with women. Conversely, while both methods diverge in their effect on lexico-syntactic readability, their association is not mandatory. We suggest that in all phase I clinical trials, the ICF be improved by either method. [source]


    Additive effect of BDNF and REST polymorphisms is associated with improved general cognitive ability

    GENES, BRAIN AND BEHAVIOR, Issue 7 2008
    F. Miyajima
    Brain-derived neurotrophic factor (BDNF) is a pleiotropic protein involved in neuronal proliferation, differentiation, synaptic plasticity and survival. Independent studies investigating association between the functional BDNF Val66Met polymorphism and cognitive abilities have reported some conflicting findings, which may reflect inadequate sample size, variation in testing methods, population stratification or the confounding effects of other genes. To test the latter hypothesis, we screened and genotyped polymorphisms in the RE1-silencing transcription factor (REST) gene whose function includes the downregulation of BDNF expression. We identified an exon 4 hexadecapeptide variable number tandem repeat (VNTR) with either four or five copies that was located within a proline-rich domain and investigated a further five single nucleotide polymorphisms (SNPs). Using a cohort of 746 community-dwelling older volunteers, we analysed REST genotype data both independently and in combination with the BDNF Val66Met polymorphism. A haplotype within the REST gene containing the four copy VNTR and a non-synonymous SNP showed a weak but significant association with a higher score of general intelligence (P = 0.05). Analysis of this haplotype and the BDNF Val66Met polymorphism in combination showed a significant interaction (global P -value = 0.0003) with an additive increase in cognitive performance for those possessing the BDNF Val66 allele and the REST haplotype containing the four copy repeat (P = 0.004). The REST haplotypes in combination with the BDNF Met66 polymorphism did not reduce cognitive performance more than the independent influence of the Met66 allele. Our results suggest that investigation of a common REST polymorphism may be necessary to help reduce contrasting reports based around BDNF Val66Met and cognition. [source]