The effect of systemic d-amphetamine on motor versus motivational processes in the rat

Reflective practice has emerged in the U.K. and beyond as an important issue not just in nursing but in many other professions. However, it remains problematic; it is difficult to conceptualize and many aspects of it are open to debate. Reflective practice is also contentious because, at a fundamental level, it raises a number of important issues for professional practitioners and the way they view their practice. The intention of this paper is to: explore some of the issues that have emerged as the profession of nursing and other professions have gained a better understanding of reflective practice; broaden the scope of the debate and refocus it; raise issues which are in need of further research.     

Subtyping versus subgrouping processes in stereotype representation.

Participants were instructed to organize information about group members either by distinguishing stereotype-consistent from stereotype-inconsistent individuals (subtyping instructions), by dividing the individuals into multiple groups on the basis of similarities and differences (subgrouping instructions), or with no explicit organizing instructions. Participants given the subtyping instructions showed greater perceived stereotypicality and homogeneity and perceived a greater difference in how typical the confirming versus disconfirming group members were, relative to subgroup participants. Study 2 demonstrated natural variation among participants in the perceived atypicality of the disconfirming relative to confirming individuals when learning about a gay activist group. Atypicality predicted perceptions of this group, even when prejudice and strength of stereotyping toward gays as a whole were statistically controlled. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Testing interval independence versus configural weighting using judgments of strength of preference.

Judges made choices and rated strengths of preference between gambles composed of 50–50 chances to receive either of 2 monetary outcomes (x, y). Others judged how much they would pay to play their chosen gamble rather than the other gamble. Judged strengths of preference violated interval independence, because they depended on the value of a common outcome. For example, judges offered to pay an average of $44 to play ($74, $100) instead of ($8, $100) but offered to pay only $24 to play ($6, $74) instead of ($6, $8). Results violated the theory that utility of gambles is a nonconfigural average of the values of the outcomes and that strengths of preference are monotonically related to utility differences. Results can be explained by a configural weight model in which the lowest outcome receives greater weight. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypertrophy of astroglial processes in the dentate gyrus of the senescent rat

Quantitative electron microscopic analysis of the supragranular zone of the dentate gyrus molecular layer has shown that the number and volume fraction of profiles of astroglial processes are significantly increased in senescent rat relative to young adults. These ultrastructural modifications, which are not associated with significant age-related changes in the number of astrocytes or in the width of the molecular layer, may result from a formation of new astroglial processes and/or elongation of existing ones. In either case, the increase in the number and volume fraction of astroglial process profiles is an indicator of age-related astroglial hypertrophy. Hypertrophy of astroglial procecesses, which seems to develop with advanced age as a response to partial deafferentation of neurons, may compensate for a decrease in the dendritic volume fraction, thereby preventing changes in the dimensions of the dentate gyrus molecular layer in senescence.     

Dietary-sodium-induced cardiac remodeling in spontaneously hypertensive rat versus Wistar-Kyoto rat

OBJECTIVE: To determine lengths and causes of pre- and in-hospital delays in thrombolytic treatment. DESIGN: A prospective national survey covering 48 of the 51 Finnish university, central and general hospitals to obtain basic data before the start of a public campaign to shorten patient-related delay in acute myocardial infarction. SUBJECTS: One thousand and twelve consecutive patients with acute myocardial infarction who received thrombolytic therapy over 3 months in 1995 and who represent 40% of all patients with confirmed acute myocardial infarction. RESULTS: The median interval between onset of infarction symptoms and initiation of thrombolytic therapy was 160 min (30-647). Only 13% of the patients received thrombolysis within 60 min and 38% within 120 min. The median time from the onset of symptoms to the call for help was 60 min (5-491), and no difference was found in patients with or without a history of previous myocardial infarction (60 and 64 min, respectively). Only 52% of the patients called to the dispatch centre. The median delay from calling for help to hospital arrival was 40 min (10-170). The median in-hospital door-to-needle thrombolysis delay was 40 min (12-196). In 13% of hospitals the median delay was more than 60 min. The emergency physician encountered difficulties in decision making in 33% of cases. CONCLUSIONS: Only 38% of the patient received thrombolysis within 2 h of onset of symptoms. Patient-related delay before they sought help accounted for the major portion of the total treatment delay. Thus the findings emphasize the importance of prompt action when people are confronted with an acute heart attack. Reorganizing the emergency medical service and emergency department routines is also a necessary target to shorten thrombolysis delays. The delay attributable to transporting patients could be shortened by initiating thrombolytic treatment in the pre-hospital setting. In Finnish hospitals, door-to-needle delay was acceptable in cases with clear indications for thrombolysis. However, emergency physicians often had diagnostic difficulties, which led to remarkably longer in-hospital delays.     

Interaction behaviors of primary versus secondary caretaker fathers.

A comparison was made between the videotaped behaviors of primary caretaker mothers and both primary and secondary caretaker fathers during face-to-face interactions with their 4-mo-old infants. The sample consisted of 36 infants, 12 observed with their primary caretaker mothers, 12 with primary caretaker fathers, and 12 with secondary caretaker fathers. Fathers in general tended to engage in significantly more game playing and less holding of their infants. Primary caretaker fathers and mothers engaged in significantly more smiling, imitative grimaces, and high-pitched imitative vocalizations than did secondary caretaker fathers. These differences were related to the primary caretaker mothers' and fathers' greater familiarity with their infants. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Discriminating between pre- versus post-theraplay treatment Marschak Interaction Methods using the Marschak Interaction Method Rating System.

The Marschak Interaction Method (MIM) is a play-based observation used to evaluate parent–child relationship quality. This study examined the ability of the Marschak Interaction Method Rating System (MIMRS) to effectively discriminate between MIMs completed pre- versus post-Theraplay treatment. Eleven parent–child dyads received at least 8 Theraplay sessions. Achenbach Child Behavior Checklists (CBCLs) completed by parents before and after treatment demonstrated significant improvement in child behaviors. Interrater reliability for MIMRS = .75. Results of dependent-samples t test revealed strong effect sizes (Cohen's d) on the total MIMRS score (?1.07) and the nurture and challenge dimensions (?1.50, ?0.76, respectively). Although these results are preliminary and modest in terms of sample size, the MIMRS was successful in capturing change in the parent–child relationship following Theraplay treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interaction of fluorescein with the dicarboxylate carrier in rat kidney cortex mitochondria

The interaction of the organic anion, fluorescein (FL), with mitochondria in renal proximal tubule cells was investigated. Confocal microscopy was used to demonstrate FL accumulation in mitochondria of intact cells. Phenylsuccinate inhibited the mitochondrial accumulation of the FL analog, carboxyfluorescein (CF) indicating that the dicarboxylate carrier may be involved in the intracellular compartmentation of organic anions. To characterize the interaction, radio-tracer uptake and respiration studies with renal mitochondria were carried out using succinate as a substrate. Respiration measurements in freshly isolated kidney cortex mitochondria revealed that FL inhibited ADP-stimulated and uncoupled respiratory rate, indicating that the organic anion inhibited the availability of succinate as a reducing agent. A similar effect on mitochondrial respiration was found for PAH and phenylsuccinate. FL inhibited 14C-succinate uptake concentration-dependently, and Dixon analysis revealed that the nature of interaction between FL and succinate was competitive, Ki values of 0.5 +/- 0.2 and 1.1 +/- 0.8 mM were calculated for respiration experiments and tracer uptake studies, respectively. The data demonstrate that FL competitively interacts with a mitochondrial dicarboxylate transporter.     

Procarboxypeptidase in rat pancreas. Overall characterization and comparison of the activation processes

In a multicenter open longitudinal clinical trial where 479 patients suffering from migraine with or without aura were recruited, patients treated at home one to three migraine attacks with their customary treatment, and subsequently, over a 3-month period, one to three migraine attacks with 6 mg sumatriptan sc using an autoinjector. The headache response to customary treatment was 19% at 1 h and 30.5% at 2 h, and was not significantly different when only attacks treated "adequately" according to accepted treatment recommendations were considered: 16% at 1 h and 35% at 2 h. In contrast, 69% and 82% of patients treated with 6 mg sumatriptan sc had mild headache or no headache at 1 and 2 h respectively, regardless of migraine type or duration of symptoms prior to treatment. Other migraine symptoms (nausea, vomiting, photo- and phonophobia) were effectively treated with sumatriptan. Recurrence of migraine was observed in 31% of patients and was well controlled by a second injection of sumatriptan. It is concluded that 6 mg sumatriptan sc, self-administered using an autoinjector, is well tolerated and more effective than most currently used acute treatments for migraine in a population of severely affected patients consulting a neurologist.     

Conceptualizing parental autonomy support: Adolescent perceptions of promotion of independence versus promotion of volitional functioning.

In current research on parenting, 2 ways of conceptualizing perceived parental autonomy support can be distinguished. Parental autonomy support can be defined in terms of promotion of independence (PI) or in terms of promotion of volitional functioning (PVF). This study aimed to establish the empirical distinctiveness of both conceptualizations and to examine their relative contribution to the prediction of adolescents' adjustment. The authors conducted 3 studies, 2 which sampled late adolescents (N = 396, mean age = 18.70 years, 79% female; and N = 495, mean age = 19.30 years, 74% female, respectively) and 1 which sampled middle adolescents (N = 153, mean age = 15.12 years, 70% female). Factor analyses pointed to the distinction between perceived PVF and PI. Structural equation modeling (SEM) indicated that whereas perceived PVF uniquely predicted adjustment ( ps .05). SEM also demonstrated that adolescents' self-determined functioning significantly mediates the relationship between perceived parental PVF and adjustment ( ps     

Attention processes in children with shunted hydrocephalus versus attention deficit-hyperactivity disorder.

Children with congenital hydrocephalus, children with attention deficit-hyperactivity disorder, and normal controls were evaluated with measures of focused attention (Visual Orienting and Detection Task), sustained attention (continuous performance test), and attention shifting (Wisconsin Card Sorting Test). Components from these tasks have been linked to attention systems mediated by anterior or posterior brain networks. Children with congenital hydrocephalus showed an inability to focus and shift attention, which specifically implicated impairment of the disengage and move components of the posterior brain attention system. Children with attention deficit- hyperactivity disorder displayed the expected performance patterns on measures of focused attention once their difficulties with sustained attention were taken into account. However, they showed problems with shifting and sustaining attention, which are commonly associated with the anterior brain attention system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interaction of hunger and thirst in the motivational arousal underlying hoarding behavior in the rat.

Conducted 3 experiments with 25 male Wistar rats in which hoarding of food could be elicited by a 16-hr food deprivation schedule. It was found that (a) prolonged water restriction, with food ad lib, failed to induce hoarding in spite of spontaneous reduction in food intake and a fall in body weight to below levels normally critical for the onset of hoarding. Thus, different physiological deficits are not necessarily equivalent or additive in elicitation of food hoarding, and water lack may suppress it. (b) Hoarding behavior was released in water-deprived Ss by a drink of water. A 30-min delay to allow absorption of the water significantly enhanced the release of hoarding. Air drinking by water-deprived Ss did not release hoarding. Thus, absence of hoarding during water lack may be caused by an active process that can be inhibited or canceled by postingestional effects of drinking but not by oropharyngeal stimulation mimicking water signals. (c) Although water lack prevented hoarding in response to self-imposed fasting, hoarding ensued at maximal rates when further food deprivation was superimposed. Thus, inhibition of hoarding by dehydration operates subtractively, not multiplicatively, and with free access to food, the inhibition of hoarding by thirst tends to be balanced exactly by the facilitatory effect of concomitant fasting; thus superadded food deprivation can take full effect. It is concluded that in states of motivational arousal, specific inhibitory mechanisms may inhibit subtractively certain activities biologically irrelevant to prevailing physiological needs. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Violations of the independence assumption in process dissociation.

L. L. Jacoby, J. P. Toth, and A. P. Yonelinas (1993) advocated a process-dissociation procedure for estimating the contributions to task performance of consciously controlled (R) versus automatic (A) memory processes. The procedure relies on the strong assumption that memory-guided performance attributable to R is stochastically independent of that attributable to A. Violations of this independence assumption can produce artifactual dissociations between estimates of R and A. Such artifactual dissociations were obtained in a series of word-stem completion experiments: R increased with presentation duration, whereas A, paradoxically, decreased. Direct evidence for nonindependence was obtained from correlations between R and A in each of the experiments. These results suggest that the independence assumption was violated, and other applications of process dissociation should not be taken at face value without a thorough evaluation of independence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of the GLUT 4 transporter in regulating rat myoblast glucose transport processes

Movement of the malaria parasite into a host erythrocyte during invasion is thought to involve polymerization of parasite actin. We have used F-actin affinity chromatography to isolate actin-binding proteins from Plasmodium knowlesi merozoites, in an attempt to identify proteins responsible for regulating parasite actin polymerization during invasion. Five major proteins, of molecular masses 75, 70, 48, 40 and 34 kDa, were reproducibly eluted from the F-actin columns. The 70 kDa actin-binding protein was identified by tryptic peptide microsequencing as heat shock protein-70 kDa (HSC70); this identification was confirmed by Western blotting with anti-HSC70 antibody, and binding of the protein to ATP-agarose. A doublet of 32/34-kDa proteins coeluted with parasite HSC70 from the F-actin and ATP-agarose columns; a complex of these three proteins was also observed by gel filtration chromatography Highly enriched fractions containing the Plasmodium HSC70/32/34 complex inhibited the polymerization of rabbit skeletal muscle actin, in vitro. This capping activity was calcium-independent, and abrogated by phosphatidylinositol 4,5-bisphosphate. The average length of the actin filaments polymerized in presence of the HSC70/32/34-kDa complex was significantly shorter than in the absence of the complex, consistent with a capping activity. The capping or uncapping of actin filament ends by the HSC70/32/34-kDa complex during invasion could provide a mechanism for localized actin filament growth and movement of the parasite into the host cell.     

Effects of alcohol on social anxiety in women: Cognitive versus physiological processes.

Randomly assigned 32 female social drinkers (18–25 yr old undergraduates) to 4 conditions in a 2?×?2 factorial design that controlled for drink content and expectations. Ss were administered either an alcoholic or a nonalcoholic beverage and were led to believe that their drinks contained or did not contain alcohol. After finishing their drinks Ss participated in a study of social anxiety in which they were requested to interact with a male confederate of the experimenter. Multiple measures, including heart rate, skin conductance, and overt behavioral and self-report responses, were recorded. Ss who expected alcohol showed significant elevations in physiological arousal and were rated as more anxious on observational measures of social behavior. Self-report measures failed to yield any differences among groups. Implications for the tension reduction theory of alcohol use and the importance of multiple response measures are discussed. (1? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Transit compartments versus gamma distribution function to model signal transduction processes in pharmacodynamics

Delayed effects for pharmacodynamic responses can be observed for many signal transduction processes. Three approaches are summarized in this report to describe such effects caused by cascading steps: stochastic process model, gamma distribution function, and transit compartment model. The gamma distribution function, a probability density function of the waiting time for the final step in a stochastic process model, is a function of time with two variables: number of compartments N, and the expected number of compartments occurring per unit time k. The parameter k is equal to 1/tau, where tau is the mean transit time in the stochastic process model. Effects of N and k on the gamma distribution function were examined. The transit compartment model can link the pharmacokinetic profile of the tested compound, receptor occupancy, and cascade steps for the signal transduction process. Time delays are described by numbers of steps, the mean transit time tau, and the amplification or suppression of the process as characterized by a power coefficient gamma. The effects of N, tau, and gamma on signal transduction profiles are shown. The gamma distribution function can be utilized to estimate N and k values when the final response profile is available, but it is less flexible than transit compartments when dose-response relationships, receptor dynamics, and efficiency of the transduction process are of concern. The transit compartment model is useful in pharmacokinetic/pharmacodynamic modeling to describe precursor/product relationships in signal transduction process.