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We can do it: the interplay of construal orientation and social comparisons under threat.

The authors investigated how a collective self-construal orientation in combination with positive social comparisons "turns off" the negative effects of stereotype threat. Specifically, Experiment 1 demonstrated that stereotype threat led to increased accessibility of participants' collective self ("we"). Experiment 2 showed that this feeling of "we-ness" in the stereotype threat condition centered on the participants' stereotyped group membership and not on other important social groups (e.g., students). Experiment 3 indicated that in threat situations, when participants' collective self is accessible, positive social comparison information led to improved math test performance and less concern, whereas in nonthreat situations, when the collective self is less accessible, positive comparison information led to worse test performance and more concern. Our final experiment revealed that under stereotype threat, only those comparison targets who are competent in the relevant domain (math), rather than in domains unrelated to math (athletics), enhanced participants' math test performance.

Affect↗

Theoretical analysis of the cognitive processing of lexical and pictorial stimuli: reading, naming, and visual and conceptual comparisons.

This article reviews the research literature on the differences between word reading and picture naming. A theory for the visual and cognitive processing of pictures and words is then introduced. The theory accounts for slower naming of pictures than reading of words. Reading aloud involves a fast, grapheme-to-phoneme transformation process, whereas picture naming involves two additional processes: (a) determining the meaning of the pictorial stimulus and (b) finding a name for the pictorial stimulus. We conducted a reading-naming experiment, and the time to achieve (a) and (b) was determined to be approximately 160 ms. On the basis of data from a second experiment, we demonstrated that there is no significant difference in time to visually compare two pictures or two words when size of the stimuli is equated. There is no difference in time to make the two types of cross-modality conceptual comparisons (picture first, then word, or word first, then picture). The symmetry of the visual and conceptual comparison results supports the hypothesis that the coding of the mind is neither intrinsically linguistic nor imagistic, but rather it is abstract. There is a potent stimulus size effect, equal for both pictorial and lexical stimuli. Small stimuli take longer to be visually processed than do larger stimuli. For optimal processing, stimuli should not only be equated for size, but should subtend a visual angle of at least 3 degrees. The article ends with the presentation of a mathematical theory that jointly accounts for the data from word-reading, picture-naming visual comparison, and conceptual-comparison experiments.

Adult↗

Social comparison activity under threat: downward evaluation and upward contacts.

Social comparison processes include the desire to affiliate with others, the desire for information about others, and explicit self-evaluation against others. Previously these types of comparison activity and their corresponding measures have been treated as interchangeable. We present evidence that in certain groups under threat, these comparison activities diverge, with explicit self-evaluation made against a less fortunate target (downward evaluation), but information and affiliation sought out from more fortunate others (upward contacts). These effects occur because downward evaluation and upward contacts appear to serve different needs, the former ameliorating self-esteem and the latter enabling a person to improve his or her situation and simultaneously increase motivation and hope. Implications for the concept, measurement, and theory of social comparison are discussed.

Humans↗

Social comparison and adjustment to breast cancer: an experimental examination of upward affiliation and downward evaluation.

In a study designed to evaluate the divergence of social comparison activities under health threat, breast cancer patients (n = 94) were assigned randomly to listen to an audiotaped interview in which the target's psychological adjustment and disease prognosis were manipulated to reflect good, poor, and unspecified psychological and physical health status. Results supported hypotheses regarding downward self-evaluative and upward affiliative comparison activity, as well as predictions regarding the influences of comparison dimension. With regard to desire for affiliation, participants demonstrated a greater desire for information and emotional support from the well-adjusted target than from the poorly adjusted target. Self-evaluation of adjustment and prognosis varied as a function of target characteristics, although a pervasive tendency toward downward comparison in self-evaluation also was noted.

Adaptation, Psychological↗

Optimistic social comparisons of older adults low in primary control: a prospective analysis of hospitalization and mortality.

Social comparison can be used strategically to bolster the self-concept. Such use may constitute secondary striving for control, when primary striving through action is unattainable. On the basis of the life span theory of control, the authors hypothesized and found that social comparison judgments would predict physical health outcomes among older adults with low primary control perceptions in the health domain. Only among such respondents, after age, sex, activities of daily living, chronic conditions, and prior hospitalization were adjusted for, did more positive social comparison judgments predict significantly lower odds of hospitalization and death over the next 2--6 years as reported in provincial health records. In later life, optimistic social comparisons may contribute to better health by providing secondary control.

Aged, 80 and over↗

Emotional and self-evaluative effects of social comparison information in later life: how are they moderated by collective self-esteem?

This study examined how the emotional and self-evaluative effects of social comparison in 162 community-dwelling older people were moderated by individual differences in their collective self-esteem (CSE), a trait that reflects valuing and identifying with reference groups. In our experimental simulation, administered 6 years after participants' CSE was measured, those with higher CSE reported significantly more positive emotions and self-evaluations only after downward comparison (i.e., with a worse-off peer), and significantly more negative emotions only after upward comparison (i.e., with a better-off peer). These findings contradict the possibility that an adaptive advantage of high CSE might result from the propensity to identify strategically with upward comparison targets. However, contrast with downward targets presents a viable alternative explanation for this advantage.

Aged↗

Identification of genes whose expression is upregulated in lung adenocarcinoma cells in comparison with type II alveolar cells and bronchiolar epithelial cells in vivo.

To identify genes whose expression is upregulated in lung adenocarcinoma (AdC) cells in comparison with noncancerous peripheral lung epithelial cells, type II alveolar cells and bronchiolar epithelial cells, as well as AdC cells, were isolated by laser capture microdissection, and subjected to cDNA microarray analysis of 637 human cancer-related genes. Each of the component cells was obtained from several different individuals and analysed independently. As a comparison, two lung AdC cell lines and two primarily cultured normal lung epithelial cell lines were also subjected to cDNA microarray analysis. Four genes, TOP2A, MMP15, MX2 and KOC1, were commonly upregulated in microdissected AdC cells in comparison with microdissected epithelial cells. Hierarchical clustering analysis revealed that differences in gene-expression profiles were more evident between cultured and uncultured cells than between cancerous and noncancerous cells. To further identify the common molecular targets of AdC cells in vivo, quantitative real-time RT-PCR was performed against the four genes upregulated by cDNA microarray analysis. The TOP2A, MMP15, MX2 and KOC1 genes were overexpressed in 10/10 (100%), 8/10 (80%), 5/10 (50%) and 3/10 (30%) microdissected AdC cell samples, respectively, in comparison with any of nine independently microdissected noncancerous epithelial cell samples. The TOP2A gene was commonly overexpressed in lung AdC cells, as previously reported. In addition, the MMP15 and MX2 genes were identified, for the first time, as being commonly overexpressed in lung AdC cells. These results strongly indicate that the MMP15 and MX2 genes could be novel markers for molecular diagnosis and therapy of lung AdC.

Adenocarcinoma↗

Comparison of EST libraries from seven beetle species: towards a framework for phylogenomics of the Coleoptera.

Relatively little is known about Coleoptera genes and genomes and how these compare in different taxa. We describe here the construction, DNA sequencing and sequence comparisons of cDNA libraries from seven beetle species. A total of 6717 bacterial colonies were screened for cDNA insert containing plasmids and 2784 size selected clones were 5'- and 3'-end sequenced to produce 1620 assembled sequences. Similarity comparisons with existing protein sequence databases revealed that 65.1% had matches (E < 10(-4)) in other organisms, with greater numbers of matches in Drosophila melanogaster than Caenorhabditis elegans and Saccharomyces cerevisiae databases. tBlastX comparisons also revealed numerous similarity hits (E < 10(-20)) in intra- and interlibrary comparisons. These results show the potential of small cDNA libraries for discovery and comparative analysis of genes useful for phylogenomic and functional studies.

Animals↗

Drug comparisons: why are they so difficult?

Comparing therapeutic agents in a drug class can be difficult. This article examines the ways in which the triptans can be and have been compared and evaluates the advantages and disadvantages of the approaches. Direct comparative trials are clearly the best method for evaluating the triptans, however, there is a scarcity of this type of data on the currently available compounds. Indirect comparison such as meta-analysis is a second method of comparing these agents but only serves as an estimate of relative efficacy or safety based on a comparison of pooled data derived from a number of different trials for each agent. Comparison of the data found in the regulatory documents represents another type of indirect comparison that can be done so long as the data is presented in a consistent format across products.

Clinical Trials as Topic↗

Comparison of therapeutic gain with therapeutic ratio for the assessment of selective 5HT(1B/1D) agonist efficacy in migraine.

OBJECTIVE: Comparison of use of therapeutic gain (TG) and therapeutic ratio (TR) for relative assessments of selective 5HT(1B/1D) agonist efficacy in the acute treatment of migraine. BACKGROUND: Comparison of selective 5HT(1B/1D) agonist efficacy in the acute treatment of migraine is complicated by the impracticality of conducting high-quality head-to-head active comparator trials for all permutations of drug, dose, and route of administration; the clinical trials that are available are usually noncontemporaneous, and have fluctuating active and placebo response rates (ARR and PRR, respectively) for the necessarily subjective endpoints. The standard primary endpoint is conversion of headache score 2 (moderate pain) or score 3 (severe pain) into score 0 (no pain) or score 1 (mild pain) at a single timepoint (usually 2 or 4 hours postdose). Two principal methods have been used for comparison of ARR between studies: TG = ARR - PRR and TR = ARR/PRR. Secondary endpoints can be treated in the same way, although the 24-hour remedication rate is the only secondary endpoint that is subject to regulatory authority standardization. Does either TG or TR have an advantage over the other? METHODS: Efficacy data were collected from published sources and included pain score conversion at 2- and 4-hour, as well as 24-hour remedication rates. TG and TR were calculated for each endpoint, as shown above. The ranges of these variables were found from all observed measures. Correlations between TG and TR were found using least squares methods. The 95% confidence intervals (CI) for TG and TR were then found for all clinical trials, and for the whole range of observed PRR. RESULTS: Values for TR and TG generally were well correlated for pain score conversion at 2 hours postdose (n = 51 clinical trials). Deviations from this correlation were greatest for drugs that were evidently very efficacious. When standardized for the observed ranges of PRR and ARR, the 95% CI for TR were narrower than for TG. A subset of these studies also reported 4-hour data (n = 23 clinical trials), but the correlation between TR and TG was again good, with narrower 95% CI for TR than TG. For the 24-hour remedication data (n = 18 trials), PRR was less variable; TR and TG again correlated well, but there was little difference in their relative 95% CI. CONCLUSIONS: For comparison of drugs in noncontemporaneous studies, when PRR fluctuates, relative ranges for TR are narrower than for TG. For assessing single clinical trial results (ie, point estimates of efficacy) TR will generally be relatively nearer to its mean than TG. For both these reasons, TR is a more robust statistic than TG.

Acute Disease↗

Posttraumatic headache: biopsychosocial comparisons with multiple control groups.

OBJECTIVE: This study examined somatic, psychological, and cognitive functioning of subjects with posttraumatic headache in comparison with multiple control groups. BACKGROUND: Posttraumatic headache is not as widely studied as other forms of headache (eg, tension-type, migraine). Previous research has suggested poor psychological functioning in patients with posttraumatic headache in comparison with other groups of patients with pain; however, this group has yet to be compared with a group of persons who have experienced trauma but are headache-free. DESIGN AND METHODS: Nineteen subjects with posttraumatic headache were studied, with full assessments available for 14 participants. Comparison groups, containing 16 participants each, included another headache group, a nonheadache group, and a trauma (motor vehicle accident) survivor nonheadache group. Participants completed several measures assessing somatic, psychological, and cognitive functioning. RESULTS: Findings revealed that the posttraumatic headache group exhibited significantly poorer functioning than the comparison groups on several measures including the Psychosomatic Symptom Checklist, Postconcussion Syndrome Checklist, axis II psychiatric diagnoses, Minnesota Multiphasic Personality Inventory, and the Daily Hassles Scale (frequency and total). Additionally, they scored higher on the following: number of axis I psychiatric diagnoses, the Daily Hassles Scale (intensity), Beck Depression Inventory, State-Trait Anxiety Inventory, and State-Trait Anger Expression Inventory. The posttraumatic headache group was similar to the other trauma group on the Posttraumatic Stress Disorder Symptom Checklist and the Life-Trauma Checklist. CONCLUSIONS: This study confirmed the distress seen in this understudied population of persons with headache and highlights areas of focus for proper assessment and treatment of those with headache and who have had an accident.

Accidents, Traffic↗

[Mono-contrast distension study of the small intestine. Comparison of conventional small bowel follow-through with enteroclysis].

PURPOSE: Development of a new monocontrast examination of the small bowel. MATERIAL AND METHODS: The new examination was applied to 20 patients with suspected bowel obstruction or inflammatory bowel disease. A contrast mixture, containing gelatin, a water-soluble contrast medium (Peritrast) and water (GPW-mixture) was given over an intestinal tube. The viscosity of the new contrast mixture was measured by rotation and flow viscosimetry. The diagnostic value and the degree of small bowel distension were determined independently by 3 examiners. By comparison 20 randomized selected small bowel follow-through examinations (SBFT) and 20 small bowel enemas were examined. Special questionnaires were used to determine subjective compatibility and discomfort. RESULTS: Due to the viscosity of the new contrast medium and the administration over an intestinal tube, a good bowel distension was achieved with the GPW mixture. The bowel distension (p: < 0.01) and the diagnostic value (p: < 0.01) of the new examination in comparison to the SBFT was characterized as being significantly better. In comparison to the small bowel enema, distension was not significantly better (p: 0.31-1.0). The diagnostic value of the small bowel enema was characterized as significantly better by one of the three examiners in comparison to the new monocontrast-distenson examination (p-level < 0.01). CONCLUSION: The monocontrast-distension examination is a potential alternative in patients in whom a small bowel enema with barium sulfate is contraindicated.

Abdomen, Acute↗

[Flicker comparison of optic disc photographs: sensitivity and specificity].

BACKGROUND: Examination and documentation of the optic nerve head are essential in monitoring glaucoma patients. Even minor changes in optic nerve head morphology can be visualised using the so-called flicker test: Two optic nerve head photographs, taken at consecutive examinations, are superimposed by projection. When occluding the pictures in a rapid alternating fashion, changes in optic nerve head morphology appear as motion. In this study, we evaluated sensitivity and specificity of the flicker test. METHOD: A set of 33 pairs of serial optic disc slides was used as gold standard. These 33 pairs had been classified earlier by 3 independent groups of experts. 23 had been classified as "no change over time", 10 had been classified as "change". All 33 pairs were now evaluated by flicker comparison in a masked fashion. RESULTS: Flicker comparison usually took 1 minute per pair of slides. Sensitivity was 90 %, specificity was 65 %. CONCLUSION: The sensitivity was reasonably high. The moderate specificity was due to some cases showing "change" with the flicker comparison which might have been overlooked by the expert groups. Flicker comparison is an easy, fast and reliable technique to evaluate pairs of consecutive optic disc photographs.

Disease Progression↗

Side-effect profile of fluoxetine in comparison with other SSRIs, tricyclic and newer antidepressants: a meta-analysis of clinical trial data.

BACKGROUND: In the last ten years, SSRIs have increasingly replaced TCAs as comparators of newer antidepressants (ADs), because of their better tolerability profile. In particular, fluoxetine has become a reference drug for the treatment of depression, but the occurrence of individual side effects in depressed subjects treated with fluoxetine and each comparator AD have not been systematically investigated. METHODS: This meta-analysis investigated the frequency of side effects induced by fluoxetine or alternative ADs and compared the occurrence of individual side effects in depressed subjects. All randomised clinical trials (RCTs) comparing fluoxetine with any other AD drug in patients with major depression were located by searching the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register and the Cochrane Controlled Trials Register. Two reviewers independently extracted information. RESULTS: Significantly less percentage of patients treated with fluoxetine experienced any side effects in comparison with TCAs (50.9 % vs 60.3 %, 29 RCTs; RR = 0.84, p = 0.003), but not in comparison with other SSRIs (59.4 % vs 59.3 %, 15 RCTs; RR = 1.00, p = 0.902). In addition, fluoxetine was better tolerated in comparison with TCAs and related ADs (RR 0.61, 95 % CI 0.52, 0.71), but not in comparison with other SSRIs. Regard to individual side effects, activating (insomnia, agitation, tremor and anxiety) and gastrointestinal adverse events (nausea, vomiting, diarrhoea, weight loss and anorexia) were significantly more frequent in fluoxetine-treated patients, whereas cholinergic side effects were significantly less frequent. CONCLUSIONS: Fluoxetine compared to other ADs had more activating and gastrointestinal adverse effects, which often require additional pharmacotherapy or other managements strategies, leading to discontinuation and non-compliance and increasing the costs. This information is relevant to base on evidence the prescription of ADs in everyday clinical practice.

Antidepressive Agents, Tricyclic↗

[The effect of the field strength on standardized MRI of the brain to demonstrate cranial nerves and vessels: a comparison of 1.5 and 3.0 Tesla].

PURPOSE: Comparison of MR images acquired as routine examinations at a field strength of 3.0 T and 1.5 T to determine whether and to which degree the image quality improves at the higher field strength of 3.0 T. MATERIALS AND METHODS: Routine MR images of 200 patients were examined retrospectively, with 100 images obtained at 1.5 T and 100 obtained at 3.0 T. The examinations were performed with a quadrature head coil and focused on the basal cisterns because of the abundance of small distinct structures in this region. We selected the T2-weighted 2D-FSE sequence in transverse direction for comparison. At both field strengths, the same section thickness of 5 mm and a matrix of 512 x 388 (FOV: 220 mm) were used. The quality of the images was evaluated with regard to depicting the cranial nerves N. III, V - X, the AICA and PICA. For comparison, image quality was rated with a score from 1 (well defined) to 5 (not depicted). RESULTS: A score of 1 was obtained in 46 % of the anatomic structures examined at 3.0 T and in only 9.2 % at 1.5 T. A score of 2 was given in 27.6 % of the anatomic structures at 3.0 T vs. 23.5 % at 1.5 T, a score of 3 in 17.2 % vs. 28.1 %, a score of 4 in 8.6 % vs. 28.7 %, and a score of 5 in 0.4 % vs. 10.3 %, respectively. The Mann-Whitney U test showed significance at p < 0.001 for the comparison of images at 1.5 and 3.0 Tesla. CONCLUSION: Routine magnetic resonance imaging using the same quadrature coil technique and similar acquisition times at 3.0 T and 1.5 T shows an improvement for T2-weighted images at the higher field strength.

Adolescent↗

Comparison of transit-time and Doppler ultrasound methods for measurement of flow in aortocoronary bypass grafts during cardiac surgery.

To evaluate the accuracy of flow measurements in aortocoronary bypass grafts with the ultrasound transit-time method, an in vitro and in vivo comparison was carried out. The in vitro comparison with evaluation against both true flow and the ultrasound Doppler method, was carried out with a fresh saphenous vein mounted in a pulsatile flow rig. The two flow probes were placed on the graft 4-5 cm apart to avoid acoustic interference, and blood was pumped through the system at different flow rates. The comparison between the methods showed excellent agreement with a linear correlation coefficient of 0.996, and a mean error of -2.9 ml/min with limits of agreement +/- 13.1 ml/min (+/- 2 SD = 95% of measured differences between these limits). However, against true flow, both methods overestimated flow slightly with mean error 4.4 and 7.3 ml/min for the transit-time and Doppler, respectively. Both methods showed excellent correlation with true flow (correlation coefficient 0.998 for the transit-time and 0.997 for the Doppler method). The in vivo accuracy was evaluated by comparison of the two methods in 9 patients. The two probes were placed on the same saphenous vein grafts 4-5 cm apart, and a total of 34 measurements in 17 grafts were carried out including measurements at baseline and after papaverine injection. The correlation coefficient was 0.990 and linear regression analysis gave the equation: Transit-time flow = 1.00 x Doppler flow + 1.3. In terms of flow, the mean error was 1.5 ml with limits of agreement +/- 17.2 ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Flow Velocity↗

Acetylcholine receptor (from Electrophorus electricus): a comparison of single-channel current recordings and chemical kinetic measurements.

We report a direct comparison between two types of measurements of the dynamic properties of the acetylcholine receptor: single-channel currents recorded using the patch-clamp technique and chemical kinetic measurements. Electrophorus electricus electroplax cells, and membrane vesicles prepared from these cells, were used. Such a comparison, and single-channel currents recorded from these cells, have not previously been reported. We first give the theoretical basis for the comparison and define the conditions under which the comparisons are elegantly simple. We relate (i) measurements of currents through receptor channels in the cell membranes to measurements of the rates of ion translocation through the receptor channels in vesicles and (ii) measurements of the lifetimes of receptor states (for instance, the lifetime of the active state of the receptor--i.e., the state in which it can form open channels) to rate coefficients obtained in chemical kinetic measurements (for instance, those for the interconversions between different states of the receptor). In eel Ringer's solution we have found the single-channel conductance (gamma) of the receptor in E. electricus electroplax cells to be 53 pS. From this value, a specific reaction rate for ion translocation, J, of 5 X 10(7) M-1 X sec-1 was calculated. When membrane vesicles prepared from the electroplax cells and the same solution compositions were used, chemical kinetic measurements gave a J value of 3 X 10(7) M-1 X sec-1. The agreement between the two measurements is important because (i) they reflect different experimental conditions, which require different assumptions in interpreting the results, and (ii) it indicates that the two techniques can be used to obtain complementary information: the methods have different time resolutions and can be used in different ranges of acetylcholine concentrations.

Acetylcholine↗

Striking sequence similarity in inter- and intra-specific comparisons of class I SLG alleles from Brassica oleracea and Brassica campestris: implications for the evolution and recognition mechanism.

Self-incompatibility in Brassica is controlled by a single multi-allelic locus (S locus), which contains at least two highly polymorphic genes expressed in the stigma: an S glycoprotein gene (SLG) and an S receptor kinase gene (SRK). The putative ligand-binding domain of SRK exhibits high homology to the secretory protein SLG, and it is believed that SLG and SRK form an active receptor kinase complex with a self-pollen ligand, which leads to the rejection of self-pollen. Here, we report 31 novel SLG sequences of Brassica oleracea and Brassica campestris. Sequence comparisons of a large number of SLG alleles and SLG-related genes revealed the following points. (i) The striking sequence similarity observed in an inter-specific comparison (95.6% identity between SLG14 of B. oleracea and SLG25 of B. campestris in deduced amino acid sequence) suggests that SLG diversification predates speciation. (ii) A perfect match of the sequences in hypervariable regions, which are thought to determine S specificity in an intra-specific comparison (SLG8 and SLG46 of B. campestris) and the observation that the hypervariable regions of SLG and SRK of the same S haplotype were not necessarily highly similar suggests that SLG and SRK bind different sites of the pollen ligand and that they together determine S specificity. (iii) Comparison of the hypervariable regions of SLG alleles suggests that intragenic recombination, together with point mutations, has contributed to the generation of the high level of sequence variation in SLG alleles. Models for the evolution of SLG/SRK are presented.

Alleles↗