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Useful Complement (useful + complement)
Selected Abstractsp27Kip1 Expression and grading of breast cancer diagnosed on cytological samplesDIAGNOSTIC CYTOPATHOLOGY, Issue 6 2004Giancarlo Troncone M.D. Abstract The progressive reduction in p27Kip1 (p27) protein immunohistochemical staining with increasing histological grading is a well-established finding occurring in breast cancer, and its role as diagnostic complement and prognostic marker has been thoroughly evaluated. To clarify whether this test may be applied to breast cytopathology, we performed p27 immunostaining on fresh fine-needle cytology (FNC) samples from 10 benign and 40 malignant breast lesions. On average, p27 immunostaining was significantly lower in carcinomas than in benign lesions (P < 0.005). In particular, among carcinomas, p27 immunostaining progressively reduced from well-to poorly differentiated lesions (G1 vs. G2, P < 0.05; G1 vs. G3, P < 0.001; G2 vs. G3; P < 0.001). A similar trend was noted in a subgroup of 20 matched FNCs and histological samples of breast carcinomas, when p27 immunostaining on FNCs was stratified according to the histological grading (G1 vs. G2, P = 0.18; G1 vs. G3, P < 0.05; G2 vs. G3, P < 0.05). In addition, p27 immunostaining on FNCs showed a good positive correlation with that on histology (Spearman R = 0.58; P < 0.01), with a diagnostic concordance between samples of 85%, by using the standard 50% positive cell cutoff. Taken in concert, our data suggest that p27 immunostaining is a reliable marker of tumor cell differentiation in breast cytopathology as well as in histopathology. Accordingly, staining FNCs for p27 may be an useful complement in addition to cytological grading in the preoperative assessment of breast cancer. Diagn. Cytopathol. 2004;30:375,380. © 2004 Wiley-Liss, Inc. [source] Past and present potential distribution of the Iberian Abies species: a phytogeographic approach using fossil pollen data and species distribution modelsDIVERSITY AND DISTRIBUTIONS, Issue 2 2010Francisca Alba-Sánchez Abstract Aim, Quaternary palaeopalynological records collected throughout the Iberian Peninsula and species distribution models (SDMs) were integrated to gain a better understanding of the historical biogeography of the Iberian Abies species (i.e. Abies pinsapo and Abies alba). We hypothesize that SDMs and Abies palaeorecords are closely correlated, assuming a certain stasis in climatic and topographic ecological niche dimensions. In addition, the modelling results were used to assign the fossil records to A. alba or A. pinsapo, to identify environmental variables affecting their distribution, and to evaluate the ecological segregation between the two taxa. Location, The Iberian Peninsula. Methods, For the estimation of past Abies distributions, a hindcasting process was used. Abies pinsapo and A. alba were modelled individually, first calibrating the model for their current distributions in relation to the present climate, and then projecting it into the past,the last glacial maximum (LGM) and the Middle Holocene periods,in relation to palaeoclimate simulations. The resulting models were compared with Iberian-wide fossil pollen records to detect areas of overlap. Results, The overlap observed between past Abies refugia,inferred from fossil pollen records,and the SDMs helped to construct the Quaternary distribution of the Iberian Abies species. SDMs yielded two well-differentiated potential distributions: A. pinsapo throughout the Baetic mountain Range and A. alba along the Pyrenees and Cantabrian Range. These results propose that the two taxa remained isolated throughout the Quaternary, indicating a significant geographical and ecological segregation. In addition, no significant differences were detected comparing the three projections (present-day, Mid-Holocene and LGM), suggesting a relative climate stasis in the refuge areas during the Quaternary. Main conclusions, Our results confirm that SDM projections can provide a useful complement to palaeoecological studies, offering a less subjective and spatially explicit hypothesis concerning past geographic patterns of Iberian Abies species. The integration of ecological-niche characteristics from known occurrences of Abies species in conjunction with palaeoecological studies could constitute a suitable tool to define appropriate areas in which to focus proactive conservation strategies. [source] Defending democracy: Reactions to political extremism in inter,war EuropeEUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 4 2001GIOVANNI CAPOCCIA While the strategies of political actors and institutions have been largely analyzed with reference to cases of democratic breakdown, democratic survival has often been viewed as a consequence of socio,economic and cultural ,preconditions'. The analysis of successful reactions to strong extremist challenges in three cases of democratic survival (Czechoslovakia, Finland and Belgium in the inter,war period) against the background of two cases of breakdown in the same historical context (Italy and the Weimar Republic) is a useful complement to this view. The analysis of the selected cases shows how a stable coalition of democratic forces can effectively protect the democratic system from dangerous extremist attacks by pursuing both repressive and inclusive strategies. [source] Situational Tests in Student Selection: An Examination of Predictive Validity, Adverse Impact, and Construct ValidityINTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 4 2002Filip Lievens The Flemish Admission Exam ,Medical and Dental Studies' is comprised of four cognitive ability tests and four situational tests, namely two work samples (i.e., a lecture and a medical text) and two video-based situational judgement tests (i.e., a physician,patient interaction and a medical expert discussion). On the basis of the Admission Exam scores of 941 candidates (359 men, 582 women) this study shows that situational tests significantly can predict better than cognitive ability tests, with lecture and text emerging as significant predictors. When situational tests are combined with cognitive ability tests, there are no mean gender differences. Situational tests also enable us to measure a broader range of constructs. For example, in this study, the personality factor Openness is related to better situational test performance. Overall, this study demonstrates that situational tests may be a useful complement to traditional student selection procedures. [source] Trait Psychology and Culture: Exploring Intercultural ComparisonsJOURNAL OF PERSONALITY, Issue 6 2001Robert R. McCrae Personality traits, studied for decades by Western personality psychologists, have recently been reconceptualized as endogenous basic tendencies that, within a cultural context, give rise to habits, attitudes, skills, beliefs, and other characteristic adaptations. This conceptualization provides a new framework for studying personality and culture at three levels. Transcultural research focuses on identifying human universals, such as trait structure and development; intracultural studies examine the unique expression of traits in specific cultures; and intercultural research characterizes cultures and their subgroups in terms of mean levels of personality traits and seeks associations between cultural variables and aggregate personality traits. As an example of the problems and possibilities of intercultural analyses, data on mean levels of Revised NEO Personality Inventory scales from college age and adult samples (N = 23,031) of men and women from 26 cultures are examined. Results showed that age and gender differences resembled those found in American samples; different subsamples from each culture showed similar levels of personality traits; intercultural factor analysis yielded a close approximation to the Five-Factor Model; and factor scores were meaningfully related to other culture-level variables. However, mean trait levels were not apparent to expert raters, casting doubt on the accuracy of national stereotypes. Trait psychology can serve as a useful complement to cultural perspectives on human nature and personality. [source] A Recursive Thick Frontier Approach to Estimating Production Efficiency,OXFORD BULLETIN OF ECONOMICS & STATISTICS, Issue 2 2006Rien J. L. M. Wagenvoort Abstract We introduce a new panel data estimation technique for production and cost functions, the recursive thick frontier approach (RTFA). RTFA has two advantages over existing econometric frontier methods. First, technical inefficiency is allowed to be dependent on the explanatory variables of the frontier model. Secondly, RTFA does not hinge on distributional assumptions on the inefficiency component of the error term. We show by means of simulation experiments that RTFA outperforms the popular stochastic frontier approach and the ,within' ordinary least squares estimator for realistic parameterizations of a productivity model. Although RTFAs formal statistical properties are unknown, we argue, based on these simulation experiments, that RTFA is a useful complement to existing methods. [source] Quantitative analysis of amyloid , peptides in cerebrospinal fluid of Alzheimer's disease patients by immunoaffinity purification and stable isotope dilution liquid chromatography/negative electrospray ionization tandem mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 24 2006Tomoyuki Oe The 40 and 42 amino-acid residue forms of amyloid beta (A,1,40 and A,1,42) in cerebrospinal fluid (CSF) have been proposed as potential biomarkers of Alzheimer's disease (AD). Quantitative analyses of A, peptides in CSF have relied almost exclusively on the use of immunoassay-based assays such as the enzyme-linked immunosorbent assay (ELISA) procedure. However, due to the ability of the A, peptides to readily self-aggregate or bind to other proteins and glassware, such analyses are extremely challenging. Analyses are further complicated by the potential of the peptides to undergo post-translational modifications and the possibilities for cross-reaction in the ELISA assays with endogenous components of the CSF. An approach based on liquid chromatography/tandem mass spectrometry (LC/MS/MS) has now been developed which overcomes these methodological issues. The key steps in implementing this new approach involved immunoaffinity purification coupled with the use of [15N]-labeled A, peptides as internal standards, a basic LC mobile phase, negative ion electrospray ionization, and a basic solvent for dissolving the peptides and washing the injection needle to prevent carryover of analytes during multiple injections on the LC/MS system. The validated method had limits of quantitation of 44,fmol/mL (200,pg/mL) for A,1,42 and 92,fmol/mL (400,pg/mL) for A,1,40. An excellent correlation was found between the LC/MS/MS assay and an ELISA assay for A,1,42 in human CSF (r2,=,0.915), although less correlation was observed for A,1,40 (r2,=,0.644). Mean CSF A,1,42 concentrations for samples collected 2 weeks apart from a limited number of AD patients provided additional confidence in the reproducibility of the LC/MS/MS assay. Concentrations for duplicate samples from AD patients were slightly higher than most previously reported values (mean 1.06,±,0.25,ng/mL; n,=,7). A,1,40 concentrations in duplicate samples obtained from AD patients were also reproducible but were found to be slightly lower than most previously reported values (mean 6.36,±,3.07,ng/mL; n,=,7). Consistent with literature reports, mean A,1,42 concentrations were found to be lower in AD patients compared with the normal subjects (mean 1.49,±,0.59,ng/mL; n,=,7), whereas there was no difference in A,1,40 concentrations between AD patients and normal subjects (mean 5.88,±,3.03,ng/mL; n,=,7). The accuracy and precision of the LC/MS assay mean that it will be a useful complement to existing ELISA assays for monitoring therapeutic interventions designed to modulate CSF A,1,42 concentrations in individual AD patients. Moreover, the introduction of stable isotope labeled internal standards offers the potential to achieve a more rigorous account of the influence of methodological effects related to sample collection and processing. Copyright © 2006 John Wiley & Sons, Ltd. [source] Assessing reproductive profiles in female brown mouse lemurs (Microcebus rufus) from Ranomafana National Park, southeast Madagascar, using fecal hormone analysisAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2009Marina B. Blanco Abstract Studies on reproductive endocrinology in wild primate populations have greatly increased in the last decades owing to the development of noninvasive techniques that can be applied under field conditions. However, small-bodied nocturnal species are not well represented on the long list of primates surveyed in the wild, and reproductive inferences regarding these animals in their natural habitats have not benefited from direct observations of hormonal changes. We collected fecal samples from female brown mouse lemurs (Microcebus rufus) in a southeastern rainforest of Madagascar in order to determine whether or not fecally excreted steroid levels show a consistent pattern of change during the reproductive season and are a useful complement to reproductive observations in wild-trapped individuals. Initial data show variation in reproductive hormone levels before and after estrus and estimated day of parturition. Elevated levels of excreted estradiol (E2) were observed around the time of estrus, whereas high levels of fecal progesterone (P) were seen during later stages of pregnancy and around parturition. A more complete picture of reproductive profiles in female mouse lemurs, and how they may change over the life span, can be obtained if hormone analyses are used to supplement field observations. Am. J. Primatol. 71:439,446, 2009. © 2009 Wiley-Liss, Inc. [source] Evaluating the usefulness of spa typing, in comparison with pulsed-field gel electrophoresis, for epidemiological typing of methicillin-resistant Staphylococcus aureus in a low-prevalence region in Sweden 2000,2004CLINICAL MICROBIOLOGY AND INFECTION, Issue 5 2010A. C. Petersson Clin Microbiol Infect 2010; 16: 456,462 Abstract The usefulness of spa typing was evaluated in relation to pulsed-field gel electrophoresis (PFGE), as a tool for epidemiological typing of methicillin-resistant Staphylococcus aureus (MRSA) in a low-prevalence region in southern Sweden. Bacterial isolates from 216 MRSA cases, newly identified in 2000,2004, were studied. The isolates were obtained from infected patients (31%), and from colonized individuals found by screening (69%). In total, 49 spa types and 73 PFGE patterns were identified. The discriminatory power of spa typing was lower (94.9 ± 1.8%) than that of PFGE (97.3 ± 1.2%). For two spa types (t002 and t008) the Panton,Valentine leukocidin results added useful discriminatory information. The most common spa types were t044 (n = 31; four PFGE patterns), t002 (n = 24; 10 PFGE patterns), t067 (n = 12; four PFGE patterns), t050 (n = 12; one PFGE pattern), and t324 (n = 11; one PFGE pattern). Epidemiological investigations identified 91 single cases and 39 transmission chains, each involving two to 13 cases. All the transmission chains were held together both by spa and PFGE typing. Among the 91 single-case isolates, 33 spa types and 50 PFGE patterns were unique (matchless) at the time of identification. The low prevalence of MRSA, the low number of outbreaks, and the wide spectrum of strains due to frequent acquisitions abroad (49% of the cases), makes spa typing a useful complement to epidemiological investigations in our setting. However, we still recommend the continued use of PFGE for further discrimination of isolates with identical spa types when epidemiological data can not exclude possible transmission. [source] Measurement of physical work capacity in patients with chronic aortic regurgitation: a potential improvement in patient managementCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 6 2009Éva Tamás Summary Background:, Timing of surgery in aortic regurgitation (AR) is important. Exercise testing is recommended upon uncertainty about functional limitations but reports on cardiopulmonary exercise testing (CPET) in populations with pure chronic AR are scarce. Method:, Twenty-eight patients referred for surgery because of chronic AR (13 in NYHA I, 10 in NYHA II and five in NYHA III) were tested by CPET pre- and 6 months postoperatively. Echocardiography, with measurement of left ventricular ejection fraction (LVEF), diameters (LVED, LVES) and volumes (LVEDV, LVESV) was also performed. Results:, The patients had normal LVEF pre- and postoperatively. LV diameters and volumes diminished significantly postoperatively (LVED from 67 to 57, LVES from 49 to 41 mm; P < 0·001). The majority of the patients had a ,low' physical work capacity, none of them performed better than ,average' according to Ĺstrand's classification preoperatively and there was no significant postoperative improvement. The mean peak oxygen uptake () was 25 ml kg,1 min,1 both pre- and postoperatively, and six of the 28 patients had a of less than 20 ml kg,1 min,1. was not significantly related to NYHA class. Conclusion:, LVEF, diameters and volumes at rest did not fulfil the criteria for surgery in most of our AR patients, of whom 46% were asymptomatic. However, many had a remarkably low work capacity, which was neither improved 6 months postoperatively nor correlated to echocardiographic LV dimensions. CPET predicted the postoperative work capacity and may, therefore, be a useful complement for timing of surgery in patients with chronic AR. [source] Tutorial: Using Confidence Curves in Medical ResearchBIOMETRICAL JOURNAL, Issue 2 2005Ralf Bender Abstract Confidence intervals represent a routinely used standard method to document the uncertainty of estimated effects. In most cases, for the calculation of confidence intervals the conventional fixed 95% confidence level is used. Confidence curves represent a graphical illustration of confidence intervals for confidence levels varying between 0 and 100%. Although such graphs have been repeatedly proposed under different names during the last 40 years, confidence curves are rarely used in medical research. In this paper, we introduce confidence curves and present a short historical review. We draw attention to the different interpretation of one- and two-sided statistical inference. It is shown that these two options also have influence on the plotting of appropriate confidence curves. We illustrate the use of one- and two-sided confidence curves and explain their correct interpretation. In medical research more emphasis on the choice between the one- and two-sided approaches should be given. One- and two-sided confidence curves are useful complements to the conventional methods of presenting study results. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||||||||