Measuring research performance of Iraqi universities using Scopus data

Scientometrics - This study investigates the research performance of the Iraqi public and private universities using the Scopus citation database. The investigation consists of three stages. The...     

Immunohistochemical determination of nuclear antigens by colour image analysis: application for labelling index, estrogen and progesterone receptor status in breast cancer

The immunohistochemical evaluation of 5-bromo-2'-deoxyuridine (BrdU) labelling index, estrogen (ER) and progesterone receptor (PR) status was carried out on the automated computer-assisted image analysis station BIOCOM 500. Special software has been developed to measure nuclear antigens using the immunoperoxidase method with the Harris hematoxylin counterstain. The analysis was based on the different light adsorption spectra of the chromogen diaminobenzidine and Harris's hematoxylin coloration when exposed to light of differing wavelengths. The results obtained by image analysis were compared to previously validated methods. The thymidine labelling index performed by manual procedures and BrdU incorporation performed by image analysis were comparable (linear correlation coefficient r = 0.76, P < 0.001). Comparison of image analysis and dextran coated charcoal assay for ER and PR content revealed excellent sensitivities and specificities (linear correlation coefficient r = 0.87, P < 0.001 for ER and r = 0.93, P < 0.001 for PR). These data suggest that automated image analysis offers a reliable and reproducible procedure for measuring nuclear antigens.     

Influence of fluorescence anisotropy on fluorescence intensity and lifetime measurement: theory, simulations and experiments

The significance of fluorescence anisotropy in fluorescence intensity and lifetime measurements, and erroneous measurements and interpretations resulting from its disregard, are thoroughly discussed, formulated and quantified. In all fluorescence-related measurements--including excitation and emission spectra, relative fluorescence intensity (FI), fluorescenc life time (FLT), fluorescence resonance energy transfer (FRET), etc., with the exception of fluorescence polarization and anisotropy--it is generally true that the higher the fluorescence anisotropy, the greater the distortion of fluorescence measurements. Quantifiable distortions occur when fluorescence measurements are conducted without considering the influence of fluorescence anisotropy. Here, this influence is described by numerous newly developed mathematical expressions which are simulated and experimentally confirmed utilizing single and binary fluorescent solutions of fluorophores with different spectroscopic characteristics. A marked agreement is shown between the theory and experimental data, clearly indicating the legitimacy of the physical suppositions and the mathematical expressions presented in this paper. Practical and instructive implications are discussed. The following findings are of special applicative importance: 1) the existence of an infinite number of couples of Magic Angles; 2) the deviation between two equally fluorescing particles having different fluorescence anisotropies; 3) the relation between the detected fluorescence intensity and anisotropy when measured under various setups of emission and excitation polarizers; 4) the dependence of the artificial normalized steady-state weight of a single-exponentially decaying fluorophore on its fluorescence anisotropy.     

Reliability of individual functional MRI brain mapping of language.

The use of individual brain mapping for a single case study implicitly assumes that the pattern of activation obtained in a single session represents the subject's functional neuroanatomy. It is therefore essential to estimate the potential variability of brain activation in individuals. To this purpose, the authors compared the pattern of activation determined by statistical parametric mapping (SPM 99) in 9 subjects who repeated 3 verbal tasks in 3 separate sessions. In each subject for each task, the authors examined the intersession variability of the volume of activation in a set of regions classically implicated in language processing. Their results show that reproducibility of functional MRI brain mapping for language within subject varies as a function of the activation task and the region of interest for language. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Magnetic resonance imaging of PLP-induced experimental allergic encephalomyelitis in Lewis rats

Despite epidemiological studies indicating a positive relationship between alcohol and stroke, little is known with regard to effect of chronic alcohol on neuronal injury after stroke. In this study, we examined the effect of chronic ethanol on mRNA levels of sarcoplasmic or endoplasmic Ca2+-ATPase (SERCA2b) and inositol 1,4, 5-triphosphate receptor (IP3R1) in gerbils subjected to global cerebral ischemia induced by ligation of both common carotid arteries. Gerbils were given daily by intragastric intubation either a liquid diet containing ethanol (4 g/kg) or the same diet with an isocaloric amount of sucrose for 35 days. They were subsequently subjected to a 5 min ischemic insult followed by reperfusion for 48 h. In agreement with other studies, ischemic insult caused significant decreases (P<0.05) in mRNA levels of both IP3R1 and SERCA2b in the hippocampal CA1 region but not in the dentate gyrus. Nevertheless, despite a significant (P<0.05) decrease in SERCA2b mRNA in the Purkinje neurons, chronic ethanol did not alter the expression of this mRNA species in the hippocampal CA1 neurons nor did it alter the decrease in SERCA2b mRNA due to cerebral ischemic insult. Since IP3R1 and SERCA2b are key mediators for regulation of intracellular Ca2+ stores, the decrease in SERCA2b mRNA but not IP3R1 mRNA in cerebellar neurons may be an important mechanism underlying alteration of calcium homeostasis and cerebellar degeneration upon chronic ethanol consumption.     

A comparative study of 4 sequential first-line chemotherapy protocols in locally advanced breast cancer]

The toxic effect of Silesian air pollutants to mouse organs was examined. Histological changes were found in the examined lymphoid organs (thymus, spleen) as well nonlymphoid organs (liver, kidneys). The alterations in weight indexes of lymphoid organs were also observed. Considerable changes in cellularity, weight index, and histology of the thymus in the mice exposed to air pollutants suggest the atrophy of this organ, which may lead to extrathymic T-cell differentiation and even acceleration of thymocytes maturation, which may lead to certain allergic or auto-immune pollutants of all investigated mouse organs in the following order: thymus, liver, kidneys, and spleen.     

Susceptibility-based MRI contrast of the CSF by intravascular superparamagnetic nanoparticles

Endorem^®, a suspension of superparamagnetic iron oxide dextran nanoparticles (NP), have been injected intravenously to healthy anesthetized rats for the purpose of contrast enhancement of brain in gradient-echo imaging at 200 MHz. Not only gray and white matter but also particular regions of the cerebrospinal fluid (CSF) were contrasted in sagittal and transverse images, although samples of this fluid did not contain NP. The selected contrast in the CSF would result from the ability of dense vascular beds containing highly magnetized particles to induce a remote susceptibility effect far beyond the vascular walls into a large fraction of extravascular water.     

Mass screening programs for breast cancer in France. Comparative evaluation

OBJECTIVE: The purpose of this work was to comparatively assess the results of mass screening programs for breast cancer implemented in six French departments in 1986, within the scope of the National Fund for Health Prevention, Education and Information of the National Health Insurance Office of Salaried Workers. MATERIAL AND METHODS: The data collected by the screening centres were analyzed by ten assessment teams that were independent from the program promotion staff, all using the same evaluation form. A complementary population study performed in eight French districts then, allowed assessing the frequency of self-referred screening (mammography performed out of program). RESULTS: The rate of participation in screening programs, in relation to the invited population, ranged from 21 to 48%, according to the district (36% in average). This low participation was probably related to the extent of self-referred screening. In fact, 19 to 40% of women, according to the district, had previously had a screening mammographic coverage: rate was around 68% in women aged 50 to 69 years. Positive findings with mammography ranged from 4.5 to 15.8% (10.1% in average), while intervention rates ranged from 0.7 to 1.6% and detection rates from 3.8 to 6.2%. The ratio between benign tumors and cancers ranged from 0.7 to 2.1 according to the district. In order to enlighten the judgement on French results, we propose a comparison with the international standards in force. CONCLUSION: The various experiences with breast cancer screening in France show that this screening is technically feasible on the basis of existing medical structures. However, some criteria are still below the expected values, especially if compared with international standards. This result is probably accounted for by the high rate self-referred screening before age 40 in France. In these conditions, the question is whether extending breast cancer screening programs in France is an appropriate course of action.     

Data-driven curvilinear reconstructions of 3D MR images: application to cryptogenic extratemporal epilepsy

This paper presents a data-driven method for the reconstruction and visualisation of curvilinear slices from three-dimensional (3D) magnetic resonance (MR) scans of the head. Visualisation of curvilinear slices, rather than standard planar slices, produces symmetrical views of the cortex and allows small abnormalities to be detected by comparing the two hemispheres of the brain. In our method, the surface defined by the upper half of the brain is used as a reference shape for curvilinear reconstructions. The brain is first segmented from the 3D scan using a 3D region growing method associated to an unsupervised threshold selection technique. The upper half of the segmented brain is then extracted and fitted by a deformable surface model. This surface is finally interactively moved by the operator in the 3D scan, to visualise the desired curvilinear slice, which is projected on the screen as a two-dimensional image. We show an application of this visualisation technique to the localisation of cerebral epileptogenic lesions. The procedure has proven efficient and handy in clinical use.     

Localized T2 measurements using an OSIRIS-CPMG method. Application to measurements of blood oxygenation and transverse relaxation free of diffusion effect

This work presents a new method allowing localized T2 measurements, based upon the OSIRIS scheme. A train of 180 degrees pulses is applied after the OSIRIS preparation cycle, recording directly the transverse magnetization decay. The method was verified for two nuclei, 1H and 19F, with phantoms and in vivo on rats. The accuracy of the T2 values is discussed, as well as possible applications of the OSIRIS-CPMG method to proton transverse spin relaxation measurements, free of diffusion effects, and to non-invasive in vivo blood oxygenation measurements, through the use of an emulsion of perfluorooctylbromide, a blood substitute containing fluorine.