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1.
Abstract

The relationship between 27 different measures of hyperactive, impulsive, and inattentive behavior, including those considered to be more objective and those considered more influenced by social factors, is examined using a normal sample of 219 Mexican children, ages 6 to 12. Measures were based on activity monitoring by accelerometry, ethological observation of attentional and movements states in the classroom, cognitive testing using the TOVA continuous performance test (CPT), and parents’ and teachers’ reports on ratings scales and symptom checklists. Factor analysis was used to examine to what degree these different measures are reporting similar underlying constructs (factors) of hyperactivity and inattention. Parent and teacher ratings appear to be describing underlying constructs that are distinct from those described by the other measures, but measures based on CPT, observation, and activity monitoring did not factor together either, nor more highly correlate to each other. Analysis combining all the measures showed that parent and teacher ratings factored together based on who was reporting the behavior, rather than the behavior being reported. The findings underscore that each type of measurement of hyperactivity, impulsivity, and inattention measures a different aspect of a complex behavioral phenomenon, rather than some better measuring than others the same underlying factor.  相似文献   

2.
The high prevalence of diabetes in African‐American (AA) women has been widely assumed to be related to the greater prevalence of obesity in this group. Catecholamine release acting on central adipose tissue has been proposed to be a contributing factor. The aim of this article was to examine the interaction of plasma catecholamines and central adiposity on fasting and nonfasting glucose levels in two separate samples. In both studies, the women were healthy, nondiabetic of similar age. In addition, both studies assessed plasma epinephrine (EPI) and norepinephrine (NOREPI) levels collected at three time points. In study 1, catecholamines were measured during a standardized laboratory mental stress task and in study 2, they were measured during the initial phase (10 min) of an intravenous glucose tolerance test (IVGTT). Results from both studies revealed significant effects of EPI on fasting glucose in the obese women. In study 1, mean EPI levels were significantly related to fasting glucose in AA women with high trunk fat (β = 0.60, P < 0.001). Because high BMI was associated with high trunk fat in women, we used BMI >30 as a proxy for high trunk fat (>32%) in study 2. In study 2, EPI response to the glucose bolus was a strong predictor of fasting glucose in AA women with BMI >30 (β = 0.75, P < 0.003). We conclude that the effect of central adiposity on fasting glucose may be moderated by plasma EPI. This suggests that adrenal medullary activity could play a role in the pathophysiology of type 2 diabetes.  相似文献   

3.
Aysun Ozkan 《Biologia》2007,62(2):232-237
The aim of this study was to evaluate that: (i) epirubicin-HCl (EPI) and lymphokine-activated killer (LAK) cells cytotoxicity may be mediated by free radical generation; and (ii) resistant H1299 cells may be more sensitive to combined treatment of LAK cells plus EPI than the LAK or EPI treatment alone. Viability of H1299 cells treated with EPI, LAK and LAK plus EPI was measured using the MTT test. Amount of glutathione (GSH), protein content and enzymatic activity were measured by spectrophotometer. Glutathione S-transferase (GST)-pi expression in the cells was determined by western blot analysis. LAK plus EPI combined treatment increased susceptibility of H1299 WT and H1299 EPI(R) (300-fold EPI resistant) cells to LAK cell cytotoxicity. The resistance of H1299 EPI(R) cells to EPI appears to be associated with a developed tolerance to free radicals, most likely because of a 2-fold increase in NADPH-dependent-cytochrome-P450 reductase (NADPH-CYP reductase) activity, 11-fold GST activity and 11-and 7-fold augmented selenium dependent and independent glutathione peroxidase (GSH-Px) activity, respectively. Amount of GST-pi in H1299 EPI(R) cells is statistically different from negative control and H1299 WT (p < 0.01). It is proposed that production of reactive oxygen species and hydrogen peroxide by the treatment of EPI and LAK cells can cause cytotoxicity of H1299 WT and H1299 EPI(R) cells. Superoxide dismutase, catalase, GSH-Px, GST, NADPH-CYP reductase and GSH must be considered as part of the intracellular antioxidant defense mechanism of H1299 WT and H1299 EPI(R) cells against reactive oxygen species. Combined treatment of EPI plus LAK cells caused the increasing cytotoxicity on the H1299 EPI(R) cells.  相似文献   

4.
A novel method was developed for studying the interaction between epirubicin hydrochloride (EPI) and bovine serum albumin (BSA) by fluorescence spectrometry. Fe3O4 magnetic nanoparticles (MNPs) synthesized and functionalized with thiol group were employed for the immobilization and separation of target BSA in reaction solutions. The concentrations of the non‐immobilized BSA and unbound EPI were obtained separately by fluorescence spectrometry. The binding constants (K a ) and number of binding sites (n ) of EPI with BSA were calculated. In this study, the K a value was 5.05 × 105 L mol?1, suggesting a strong binding of EPI to BSA, and the n value was 1.15. The effects of common metal ions on K a of EPI with BSA were also investigated, and the results showed there was clearly bindings between the metal ions and BSA. The precise binding sites of EPI on BSA were determined as being in site I from the competitive displacement experiments. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

5.
6.
Objective: Observational studies suggest that monounsaturated (MUFA) and trans fatty acids (TRANS) are more fattening than polyunsaturated fatty acids (PUFA). Therefore, the aim of this study was to investigate the acute effect of intake of PUFA, MUFA, or TRANS on appetite and energy expenditure (EE). Research Methods and Procedures: Three test meals were randomly given in a cross‐over design to 19 overweight (BMI: 26.8 ± 0.4 kg/m2), young (25.2 ± 0.7 years) men. The fat‐rich breakfasts (0.8 g fat/kg body weight, 60% energy from fat) varied only in the source of C:18‐fat. EE was measured continuously in a respiration chamber, and appetite sensations were rated by visual analog scales before and every 30 minutes, for 5 hours, after the meal. After 5 hours, an ad libitum meal was served, and energy intake was registered. Sensory evaluations of all meals were given using visual analog scales. Data were analyzed by two‐way ANOVA. Results: There were no differences in basal or postprandial values of appetite ratings and EE, in subsequent ad libitum energy intake, or in the sensory evaluation of the test meals among the 3 test days. Discussion: Giving acutely large amounts of MUFA, PUFA, or TRANS did not impose any differences in appetite and EE in overweight humans. However, studies with extended protocols and other subject groups are warranted to investigate the long‐term effect of dietary fat quality on the regulation of energy balance and body weight.  相似文献   

7.
P K Randall 《Life sciences》1985,37(15):1419-1423
Dose-response curves for apomorphine-induced behavior were determined in C57BL/6J mice with and without a 30 day treatment with 2.5 mg/kg/day haloperidol. The effect of the chronic neuroleptic, whether assessed by the dose-response curve for total ratings or by a multiple logistic method determining ED50's for transitions between individual stereotype ratings, was to shift the curve to the left by a factor of slightly less than 2. This estimate is considerably different from those using the rotational model and denervation as the supersensitizing stimulus. There was no indication of selective effects of the neuroleptic treatment on individual components of the behavioral response.  相似文献   

8.
Cursorial spiders are important predators of crop pests in a variety of agricultural systems. Their survivorship, growth, and fecundity can be enhanced by the consumption of extra‐floral nectar. We recently showed that Hibana futilis (Banks) (Araneae: Anyphaenidae) engages in restricted area search following contact with nectar, is stimulated by nectar aroma, and can learn to recognize novel aroma cues. Studies have shown that H. futilis is also responsive to solvent extracts of the eggs and scales of the corn earworm, Helicoverpa zea Boddie (Lepidoptera: Noctuidae), one of its primary prey insects in cotton. The arrestment behavior of cursorial spiders following consumption of prey and non‐prey food has not been characterized. In the present study, the responses of spiders were measured following consumption of prey (H. zea eggs) or non‐prey (droplets of dilute honey) food items and compared with individuals tested without food items. The food items were presented to the spiders in test arenas constructed from the top of an inverted glass Petri dish cover. A combination of real time and recorded observations were made via a video camera attached to a computer. The behaviors and movement patterns of individual spiders were analyzed with behavioral tracking software. Significant differences in the behaviors and motion paths of spiders tested in the different treatments were observed. Hibana futilis displayed significantly more dispersal behavior on a blank test arena, than on test arenas supplied with honey droplets or moth eggs. Likewise, spiders tested on the blank arena crawled faster and their motion paths were significantly less tortuous than those of spiders tested in the arenas with honey or moth eggs. Following consumption of both the honey droplets and moth eggs, spiders showed elevated levels of restricted area search and lowered levels of dispersal behavior. The analysis showed that these spiders could crawl rapidly for extended distances. Behaviors such as restricted area search and learned recognition of food‐based stimuli would facilitate efficient location of the food resources needed to maintain their high activity levels.  相似文献   

9.
Only about one third of humans possess a microbiota capable of transforming the dietary isoflavone daidzein into equol. Little is known about the dietary and physiological factors determining this ecological feature. In this study, the in vitro metabolism of daidzein by faecal samples from four human individuals was investigated. One culture produced the metabolites dihydrodaidzein and O-desmethylangolensin, another produced dihydrodaidzein and equol. From the latter, a stable and transferable mixed culture transforming daidzein into equol was obtained. Molecular fingerprinting analysis (denaturing gradient gel electrophoresis) showed the presence of four bacterial species of which only the first three strains could be brought into pure culture. These strains were identified as Lactobacillus mucosae EPI2, Enterococcus faecium EPI1 and Finegoldia magna EPI3, and did not produce equol in pure culture. The fourth species was tentatively identified as Veillonella sp strain EP. It was found that hydrogen gas in particular, but also butyrate and propionate, which are all colonic fermentation products from poorly digestible carbohydrates, stimulated equol production by the mixed culture. However, when fructo-oligosaccharides were added, equol production was inhibited. Furthermore, the equol-producing capacity of the isolated culture was maintained upon its addition to a faecal culture originating from a non-equol-producing individual.  相似文献   

10.
Exocrine pancreatic insufficiency (EPI) is a digestive disorder resulting from the insufficient secretion of enzymes from the pancreas. In dogs, this condition is often attributed to pancreatic acinar atrophy, wherein the enzyme‐producing acinar cells are believed to be destroyed through an autoimmune process. Although EPI affects many diverse breeds, to date, molecular studies have been limited to the German Shepherd dog. A recent study of major histocompatibility genes in diseased and healthy German Shepherd dogs identified both risk and protective haplotypes. Herein, we genotyped DLA‐DQB1 in Pembroke Welsh Corgis to determine whether dog leukocyte antigen alleles contribute to the pathogenesis of EPI across dog breeds. We evaluated 14 affected and 43 control Pembroke Welsh Corgis, which were selected based on an age of onset similar to German Shepherd dogs. We identified one protective allele (odds ratio = 0.13, P‐value = 0.044) and one risk allele (odds ratio = 3.8, P‐value = 0.047). As in German Shepherd dogs, the risk allele is a duplication of DLA‐DQB1 (alleles DQB1*013:03 and 017:01); however, Pembroke Welsh Corgis have acquired a single polymorphism on DQB1*017:01. Thus, the DLA‐DQB1 duplication is a risk allele for EPI in at least two breeds.  相似文献   

11.
Objective: To determine whether the consumption of water 30 minutes before an ad libitum meal reduces meal energy intake in young and older adults. Research Methods and Procedures: Healthy, non‐obese young (n = 29; age, 21 to 35 years) and older (n = 21; age, 60 to 80 years) individuals were provided with an ad libitum lunch meal on two occasions. Thirty minutes before the lunch meals, subjects were given either a water preload (WP: 375 mL, women; 500 mL, men) or no preload (NP). Energy intake at the two lunch meals was measured. Visual analog scales were used to assess changes in hunger, fullness, and thirst during the meal studies. Results: There was no significant difference in meal energy intake between conditions in the young subjects (892 + 51 vs. 913 ± 54 kcal for NP and WP, respectively; p = 0.65). However, meal energy intake after the WP was significantly reduced relative to the NP condition in the older subjects (682 + 53 vs. 624 ± 56 kcal for NP and WP, respectively; p = 0.02). This effect was caused primarily by the reduction in meal energy intake after water consumption in older men. Hunger ratings were lower and fullness ratings were higher in older compared with younger adults (p < 0.01). Fullness ratings were higher in the WP condition compared with the NP condition for all subjects (p = 0.01). No age differences in thirst were detected during the test meals. Discussion: Under acute test meal conditions, pre‐meal water consumption reduces meal energy intake in older but not younger adults. Because older adults are at increased risk for overweight and obesity, intervention studies are needed to determine whether pre‐meal water consumption is an effective long‐term weight management strategy for the aging population.  相似文献   

12.

ABSTRACT

Using the observational analysis of two different foods as test products, this note examined some interesting findings that emerge when the just‐about‐right (JAR) scale was placed after the overall liking rating, and before the preference ranking. The JAR data appeared to be statistically uncorrelated with the overall rating scales. First, this fortuitous observation from several studies suggests that the JAR scale can play a diagnostic role to determine how the consumer feels about changing the product. Second, the statistical analysis of the JAR ratings (e.g., bipolar nature of the JAR scale, its skewness and kurtosis) all suggest that the appropriate measure is %JAR, an incidence metric, rather than scale average, ought to be used both to report the results, and to create models relating to the JAR versus sensory magnitude or versus liking, respectively.

PRACTICAL APPLICATIONS

The results of the present analysis suggest that overall acceptance/liking can be the last question in the questionnaire design. That location is very important for the sensory analysis of foods eaten over time and then rated, as well as personal care and cosmetic studies where the products are used over time periods, and where the true evaluation of performance ought to be made at the end of the trial. In these long‐term uses, overall liking is generally the last question given at the end of the time period of product evaluation. The facts that the just‐about‐right (JAR) scales are independent of this final overall liking rating suggest that the integrity of the overall evaluation and usefulness of JAR as diagnostics will not be compromised.  相似文献   

13.
Three isosexual social groups, each containing ten subadult female hamadryas monkeys (Papio hamadryas) were studied for seven months to test three hypotheses dealing with the assumptions underlyingSeyfarth's (1977) model of allogrooming and social organization. Aggression, avoid and allogrooming behaviors were used as criteria for studying the social organization of the groups. UsingLandau's (1951) index and discriminant analyses, we found that each of the three isosexual female social units conformed to a model of social organization having a non-linear hierarchy and only two major strata: a dominant animal and subordinates who were largely undifferentiated. This aspect of social organization is similar to the normal one-male unit leader harem form of social organization that is typical of hamadryas. However, since no male was present, the role of unit leader was filled by a female. The length of allogrooming bouts and the amount of allogroom received was affected by the social status of the recipient, with high status individuals receiving more than low status individuals. Social peers were not observed competing for access to high status individuals and did not exchange most of their grooming among themselves. We found that the assumptions underlyingSeyfarth's (1977) model were not appropriate for the type of social organization typically found in hamadryas monkeys, thus suggesting the need for further modification of the model so that it fits available data.  相似文献   

14.
The first intron (EPI) of rice 5-enolpyruvylshikimate 3-phosphate synthase gene was isolated by PCR from one clone with genomic EPSP synthase gene. Sequence analysis showed that the first intron is 704 bp in length with 36.2% G+C content. To investigate its effect on expression of foreign gene, we inserted the first intron between CaMV35S promoter and β-glucuronidase (GUS) gene. The transient expression results showed that GUS could be expressed effectively with EPI. The GUS activity in transgenic tobacco shows that the EPI can greatly enhance the expression level of β-glucuronidase (P < 0.01) compared with transgenic tobacco without the first intron, and 3-to 6-fold increase in GUS activity in some transgenic tobaccos. Northern blot indicated the first intron was spliced from GUS pre-mRNA, and the steady-state mRNA levels of GUS with EPI in transgenic tobaccos were higher than that in transgenic tobacco without EPI, which suggested that the first intron of EPSP was a non-translated intron.  相似文献   

15.
An examination has been made of clones of Cricosphaera from the Plymouth culture collection. These organisms are biflagellate motile coccolithophorids which, in culture, produce non-motile filamentous benthic phases similar to forms included in the Chrysotilaceae (e.g. Apistonema).

Cricosphaera carterae (Plymouth No. 17) produces, in liquid culture, motile cells invested with several layers of characteristically patterned scales and one layer of coccoliths. The scales are of three types, (I) small oval scales, (II) medium-sized round scales and (III) large oval scales which are always associated with coccoliths.

Growth on agar produces Apistonema-like cells which, although lacking scales of Types I and III, have a greatly thickened investment of closely packed Type II scales. Other Apistonema type clones, previously believed to be covered in mucilage, are similarly ensheathed by thick layers of scales which are thought to aid the benthic phases in withstanding dry conditions.  相似文献   

16.
Objective: To determine whether Stunkard's Figure Rating Scale (FRS) is a valid and reliable index of weight status when an unbiased observer assigns the figure ratings of adult women viewed on videotape. Research Methods and Procedures: Seventy‐two women drawn from a community sample participated in a videotaped study in which height and weight were measured. The FRS is a rating scale displaying 9 silhouettes ranging from very thin to very obese. Women were assigned a figure rating “in‐person” by a research assistant (FRS used as a 17‐point scale) and by additional research assistants viewing women only on videotape (FRS used as both a 17‐ and 9‐point scale). Pearson's correlation coefficients were calculated for in‐person figure ratings, mean videotape figure ratings, and BMI. Results: BMI and in‐person figure ratings were highly correlated (r = 0.91), as were BMI and both mean 17‐point videotape figure ratings and mean 9‐point videotape figure ratings (r = 0.89 and 0.87, respectively). Inter‐rater agreement for in‐person figure ratings and mean 17‐point videotape figure ratings was 0.86, and agreement between in‐person figure ratings and mean 9‐point videotape figure ratings was 0.82. Discussion: The FRS can be used as an index of women's weight status by an unbiased observer, with subjects viewed in‐person or on videotape.  相似文献   

17.
The geographic variation inFritillaria graeca, an endemic of Greece, is explored, using multivariate techniques. Eleven morphological features were measured in each of 630 individual plants from 38 localities throughout the range of the species.Scheffe's a posteriori test revealed an almost continuous geographic variation and did not identify groups clearly. Discriminant analysis of the groups derived from an F significance test ofMahalanobis distance resulted in five major groups on the first two discriminant axes representing the subspeciesgraeca, ionica, guicciardii, thessala and its var.othria. A diagnostic key to theF. graeca subspecies is provided.This paper is a part of a doctoral dissertation dealing withFritillaria in Greece, to be submitted to the department of Biology of the Aristotelian University of Thessaloniki.  相似文献   

18.
The elasmoid scales of anadromous sea trout Salmo trutta L. represent a significant internal reservoir of Ca2+. Although more is known about long-term remodelling of scales in response to calciotropic challenges encountered during smoltification and migration, very little is known about the contribution made by scales to the short-term, minute-to-minute regulation of Ca2+ homeostasis in the extracellular fluid (ECF) during these phases of the life cycle. This gap in the knowledge is partly due to the technical challenges involved in measuring small Ca2+ fluxes around the scales of live fish in real time. Here, this study describes exfoliating, mounting and culturing scales and their resident cells from parr, smolt and adult sea trout from a freshwater environment, as well as from adult sea trout caught in sea or brackish water. All the scales were then examined using an extracellular, non-invasive, surface-scanning Ca2+-sensitive microelectrode. The authors quantified the Ca2+ fluxes, in the absence of any systemic or local regulators, into and out of scales on both the episquamal and hyposquamal sides under different extracellular calcemic challenges set to mimic a variety of ECF-Ca2+ concentrations. Scales from the life-cycle stages as well as from adult fish taken from sea, brackish or fresh water all showed a consistent efflux or influx of Ca2+ under hypo- or hypercalcemic conditions, respectively. What were considered to be isocalcemic conditions resulted in minimal flux of Ca2+ in either direction, or in the case of adult scales, a consistent but small influx. Indeed, adult scales appeared to display the largest flux densities in either direction. These new data extend the current understanding of the role played by fish scales in the short-term, minute-to-minute homeostatic regulation of ECF-Ca2+ concentration, and are similar to those recently reported from zebrafish Danio rerio scales. This suggests that this short-term regulatory response might be a common feature of teleost scales.  相似文献   

19.
Summary To measure productivity of Agave deserti over its elevational range in the northwestern Sonoran Desert, leaf unfolding from its basal rosette was monitored on groups of 10 plants at 13 sites. Based on data from an intermediate elevation (840 m), leaf unfolding proved to be highly correlated (r 2=0.88) with an environmental productivity index (EPI) formed as the product of indices for water status, temperature, and photosynthetically active radiation (PAR); each of these latter indices indicated the fraction of maximum net CO2 uptake expected for that parameter based on laboratory measurements of gas exchange and field microclimatic data. At 840 m, the main environmental variable influencing leaf unfolding for A. deserti over a 2-y period was soil water potential. On steep slopes, however, leaf unfolding during the winter ranged from 0.7 leaves per 10 plants for north-facing slopes to 7.3 for south-facing slopes, reflecting the importance of PAR. Summer and winter rainfall increased 3-fold from elevations of 300 m to 1,200 m. Temperatures were more optimal for net CO2 uptake at high elevations in the summer and at low elevations in the winter. Hence EPI increased with elevation in the summer but was maximal at an intermediate elevation in the winter. Moreover, measured leaf unfolding in both the summer and the winter closely followed the changes in EPI with elevation, indicating that productivity could be closely predicted for A. deserti based on physiological CO2 responses and changes in environmental conditions with elevation.  相似文献   

20.
The outer epidermal hair structure of bushbabies or galagos varies considerably between genera and species. Comparative morphology can therefore be useful in taxonomic studies, particularly when assessing the true status of newly nominated or misclassified species. Quantitative measurements of outer epidermal hair scales (scale frequency and scale complexity) were made for populations representing 13 taxa within the subfamily Galagoninae. Intraspecific variations in both measures of hair morphology were relatively minor. By contrast, significant interspecific differences were observed, even between closely related, well-established species (e.g. in the greater galagosOtolemur crassicaudatus andO. garnettii and lesser galagosGalago senegalensis andGalago moholi). Assessment of scale frequency resulted in the recognition of all species of the greater and needle-clawed galago genera and added support for nomination to species status of two former subspecies (O. argentatus andE. pallidus). Similar divisions were made in the lesser and dwarf galagos with respect to scale complexity. Possible explanations for the differences in outer epidermal hair scales are discussed. Characteristics of outer epidermal hair scales provide a useful guide to species identity in the subfamily Galagoninae, and the same may prove to be true for other groups of nocturnal mammals.  相似文献   

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