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Complementary Tool (complementary + tool)
Selected AbstractsCell Subpopulation-related Volumetric Parameters: a Complementary Tool of the Modified Hypo-osmotic Swelling Test on Model of Boar SpermatozoaREPRODUCTION IN DOMESTIC ANIMALS, Issue 5 2000A. Petrounkina Content It is a general property of the intact animal cell to swell rapidly in response to hypo-osmotic conditions. The modified hypo-osmotic swelling test (HOS-test) is an indicative test to evaluate the integrity of the plasma membrane by means of an electronic cell counter, based on the relative increase of the cell volume in response to hypo-osmotic conditions. In this study the relationships between the osmotically induced changes of the cell volume of boar spermatozoa as determined by cell counter and the integrity of the membrane as determined by propidium iodide staining (PI) were studied. Boar sperm cell volume distributions were measured under iso-osmotic (300 mosmolar) conditions and after a hypo-osmotic stress (150 mosmolar). The relative volume shift of mean and modal volume were calculated as a proportion coefficient of modal and mean values of the cell volume distributions by transition from iso-osmotic to hypo-osmotic conditions. The volumetric parameters related to the different cell subpopulations were derived from the different peaks of cell volume distributions. PI-staining techniques were used for comparison. The values of the volume shift and of derived percentages of the osmotically inactive cells were correlated negatively and positively, respectively (p < 0.05) with the percentage of the PI-stained cells. This correlation indicates that a relationship exists between membrane functions of the different cell compartments (sperm head and tail) due to the circumstance that the increase of the cell volume in the HOS-test is associated with the morphological changes in the tail and the PI-staining is associated with the membrane integrity and permeability of the head region. The advantage of computer-assisted volume measurement is that a large number of cells (5000,50 000 spermatozoa) can be measured and evaluated during one procedure and in a very short time. The relative volume shift is a quantitative continuous parameter characterizing the osmotic reactivity and membrane functional competence of a cell population and of subpopulations within one ejaculate. This parameter could be useful to evaluate membrane functional competence rapidly and sensitively. Inhalt Es ist eine generelle Eigenschaft membranintakter tierischer Zellen, mit einer Volumenzunahme auf eine hypoosmotische Belastung zu reagieren. Der auf der relativen Vergrößierungdes Zellvolumens basierende modifizierte hypoosmotischeSchwelltest ist ein indikativer Test zur Beurteilung der Membranintegrität mittels eines elektronischen Partikelzählers. In dieser Studie wurden die Zusammenhänge zwischen der mittels der Propidiumjodid-Färbung bestimmten Zellmembranintegrität und den osmotisch induzierten Veränderungen des Zellvolumens von Eberspermien untersucht. Volumenverteilungen von Eberspermien wurden unter isoosmotischen (300 mosmolar) und hypoosmotischen (150 mosmolar) Bedingungen gemessen. Die relative Volumenverschiebung der modalen und mittleren Werte der Volumenverteilung wurde als Quotient aus Modalwerten der Zellvolumenverteilungen und des mittleren Zellvolumens beim Übergang von isotonen zu hypotonen Bedingungen berechnet. Die auf verschiedene Subpopulationen bezogenen volumetrischen Parameter werden aus den originalen Volumenverteilungen berechnet. Der Betrag der Zellvolumenzunahme und die aus den Volumenverteilungen bestimmten Anteile an Zellen mit beschädigter Geißielmembran korrelierten signifikant negativ bzw. positiv (p < 0,05) mit dem Anteil an den Zellen mit beschädigter Kopfmembran, der sich aus der Propidiumjodid-Färbung ergab. Es wird geschlossen, daßi im Verhalten zwischen den Membranen der verschiedenen Zellkompartimente (Spermienkopf und-Geißiel) ein Zusammenhang besteht. Die beschriebene Methode ermöglicht die Analyse großier Zellpopulationen (5.000,50.000 Zellen). Die relative Volumenverschiebung stellt einen quantitativen kontinuierlichen Parameter dar, der den Membranzustand der Eberspermien einer Spermatozoenpopulation und Subpopulationen innerhalb eines Ejakulates charakterisiert. Diese Parameter können zur schnellen und sensitiven Beurteilung der Membranzustandes eingesetzt werden. [source] Spatial Analysis and Surname Analysis: Complementary Tools for Shedding Light on Human Longevity PatternsANNALS OF HUMAN GENETICS, Issue 2 2008A. Montesanto Summary Starting from the observation that human longevity patterns show regional variations, we applied Spatial Analysis (using the Geographic Information System) and Surname Analysis to highlight the effect of the population genetic structure on such patterns. The study was carried out in Calabria, a southern Italian region which is characterized by a wide variability of geographic features (high mountains and deep valleys which created geographic isolates in the past). We identified three zones of high longevity: a male and a female longevity zone were located near the town of Cosenza (northern Calabria), while a male longevity zone was located in a mountainous and quite isolated part of the province of Reggio Calabria (southern Calabria). The latter zone was characterized by the lowest Female/Male ratio in nonagenarians observed to date. By applying surname analysis (Fisher's alpha) we found a significant negative correlation between surname abundance and index of longevity, showing that this isolated zone of male longevity presents a high level of inbreeding. On the whole, the results showed the effectiveness of spatial analysis in revealing geographical longevity patterns, and highlighted the importance of the population genetic structure in shaping such patterns. [source] Computer-based management environment for an assembly language programming laboratoryCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 1 2007Santiago Rodríguez Abstract This article describes the environment used in the Computer Architecture Department of the Technical University of Madrid (UPM) for managing small laboratory work projects and a specific application for an Assembly Language Programming Laboratory. The approach is based on a chain of tools that a small team of teachers can use to efficiently manage a course with a large number of students (400 per year). Students use this tool chain to complete their assignments using an MC88110 CPU simulator also developed by the Department. Students use a Delivery Agent tool to send files containing their implementations. These files are stored in one of the Department servers. Every student laboratory assignment is tested by an Automatic Project Evaluator that executes a set of previously designed and configured tests. These tools are used by teachers to manage mass courses thereby avoiding restrictions on students working on the same assignment. This procedure may encourage students to copy others' laboratory work and we have therefore developed a complementary tool to help teachers find "replicated" laboratory assignment implementations. This tool is a plagiarism detection assistant that completes the tool-chain functionality. Jointly, these tools have demonstrated over the last decade that important benefits can be gained from the exploitation of a global laboratory work management system. Some of the benefits may be transferable to an area of growing importance that we have not directly explored, i.e. distance learning environments for technical subjects. © 2007 Wiley Periodicals, Inc. Comput Appl Eng Educ 15: 41,54, 2007; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20094 [source] Circulating EM66 is a highly sensitive marker for the diagnosis and follow-up of pheochromocytomaINTERNATIONAL JOURNAL OF CANCER, Issue 8 2006Johann Guillemot Abstract We have previously demonstrated that measurement of tissue concentration of the novel secretogranin II-derived peptide EM66 may help to discriminate between benign and malignant pheochromocytomas. The aim of the present study was to characterize EM66 in plasma and urine of healthy volunteers and pheochromocytoma patients, in order to further evaluate the usefulness of this peptide as a circulating marker for the management of the tumors. HPLC analysis of plasma and urine samples demonstrated that the EM66-immunoreactive material coeluted with the recombinant peptide. In healthy volunteers, plasma and urinary EM66 levels were, respectively, 2.6 (1.9,3.7) ng/ml and 2.9 (1.9,4.6) ng/ml. In patients with pheochromocytoma, plasma EM66 levels were 10-fold higher than those of healthy volunteers (26.9 (7.3,44) ng/ml), and returned to normal values after removal of the tumor. In contrast, urinary EM66 levels were not significantly different from those of healthy volunteers (3.2 (2.2,3.9) ng/ml). Measurement of total or free plasma metanephrines and 24 hr urinary metanephrines in our series of patients revealed that these tests, taken separately, are less sensitive than the EM66 determination. Pheochromocytes in primary culture secreted high levels of EM66, suggesting that the chromaffin tumor was actually responsible for the increased plasma peptide concentrations in the patients. These data indicate that EM66 is secreted in the general circulation and that elevated plasma EM66 levels are correlated with the occurrence of pheochromocytoma. Thus, EM66 is a sensitive plasma marker that should be considered as a complementary tool in the management of pheochromocytoma. © 2005 Wiley-Liss, Inc. [source] Lymphocytapheresis in the treatment of psoriasis vulgaris ,,JOURNAL OF CLINICAL APHERESIS, Issue 3 2006Giancarlo Maria Liumbruno Abstract Psoriasis is a common autoimmune chronic inflammatory skin disease that affects approximately 2% of the world's population; fundamental for its immunopathogenic mechanism is secretion of type 1 (Th1) cytokines by T cells and their activation. Since cytapheresis has been widely applied to autoimmune disorders, emphasizing the recently reported results of granulocyte and monocyte adsorption apheresis in psoriasis, a small series of psoriasis vulgaris (PV) patients underwent lymphocytapheresis (LCA) with the aim to remove lymphocytes. Five patients were submitted to weekly LCA. The severity of the disease had been evaluated through psoriasis area and severity index (PASI) score before LCA and one week after the last apheresis. PASI score before: patient A: 66; patient B: 33; patient C: 50; patient D: 56; patient E: 29. All the patients showed improvement of skin lesions. PASI score after LCA: patient A: 24; patient B: 8; patient C: 5; patient D: 36; patient E: 2.1. No side effects linked to apheresis were reported. LCA seems to produce interesting results in PV, and PASI improvement related to apheresis is clinically significant. Further studies to address its mechanism of action and potential long-term side effects are needed. It could become a valuable therapeutic alternative or a complementary tool, which might even be used to reduce the dosages of conventional pharmacological therapies adopted for this chronic disease. J. Clin. Apheresis 2006. © 2006 Wiley-Liss, Inc. [source] Semiautomatic sequence-specific assignment of proteins based on the tertiary structure,The program st2nmrJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 3 2002Primo, Pristov Abstract The sequence-specific assignment of resonances is still the most time-consuming procedure that is necessary as the first step in high-resolution NMR studies of proteins. In many cases a reliable three-dimensional (3D) structure of the protein is available, for example, from X-ray spectroscopy or homology modeling. Here we introduce the st2nmr program that uses the 3D structure and Nuclear Overhauser Effect spectroscopy (NOESY) peak list(s) to evaluate and optimize trial sequence-specific assignments of spin systems derived from correlation spectra to residues of the protein. A distance-dependent target function that scores trial assignments based on the presence of expected NOESY crosspeaks is optimized in a Monte Carlo fashion. The performance of the program st2nmr is tested on real NMR data of an ,-helical (cytochrome c) and ,-sheet (lipocalin) protein using homology models and/or X-ray structures; it succeeded in completely reproducing the correct sequence-specific assignments in most cases using 2D and/or 15N/13C Nuclear Overhauser Effect (NOE) data. Additionally to amino acid residues the program can also handle ligands that are bound to the protein, such as heme, and can be used as a complementary tool to fully automated assignment procedures. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 335,340, 2002 [source] Morphometric Investigation of Death by AsphyxiaJOURNAL OF FORENSIC SCIENCES, Issue 3 2009Raffaele Giorgetti M.D. Abstract:, The aim of this study was to investigate the possibility of distinguishing deaths by asphyxia from those due to natural causes by comparing morphometric measurements in lungs. The study population comprised 27 subjects: 14 cases of death by asphyxia (hanging or drowning) and 13 cases of sudden natural death. Eighty parenchyma sections were used for each subject. Data were collected by computerized image analysis. Measurements aimed at quantifying, as percentages, pulmonary parenchyma (mean values of positive-fraction areas [PFA] and their standard deviations). Subjects who died of natural causes and of drowning showed a relative internal homogeneity compared to those who hanged. Results show significant discrimination between drowned subjects and those dying of natural causes (mean of PFA p = 0.01) and between hanged and drowned subjects (SD of PFA p = 0.04). Attention must be paid to the possible role played by senile emphysema. The method is proposed as a complementary tool in forensic cases. [source] Predicting the Histopathological Grade of Cerebral Gliomas Using High b value MR DW Imaging at 3-TeslaJOURNAL OF NEUROIMAGING, Issue 3 2008Juan Alvarez-Linera MD ABSTRACT BACKGROUND Our aim was to prospectively assess whether magnetic resonance (MR) diffusion-weighted (DW) imaging using high b values can predict better than b value of 1,000 s/mm2 the histopathological grade of cerebral gliomas. METHODS Fifty-four patients with histologically verified brain gliomas (35 high-grade and 19 low-grade gliomas) underwent MR DW imaging. Isotropic DW images and apparent diffusion coefficient (ADC) were obtained with b values of 1,000 and 3,000 s/mm2. Each tumor was evaluated as being hyperintense, iso-intense or hypointense to normal, contralateral-hemisphere white matter. RESULTS Most of the patients with high- and low-grade gliomas showed areas of increased signal intensity on their isotropic images, obtained with a b value of 1,000 s/mm2. However, with a b value of 3,000 s/mm2 the areas of increased signal intensity were seen in 97.1% of the high-grade gliomas, while 94.7% of the low-grade gliomas showed no area of increased signal intensity. The mean area under the ROC curve for ADC ratio, obtained with a b value of 3,000 s/mm2, was significantly higher than that obtained with 1,000 s/mm2 (.932 vs. .856, P= .04). CONCLUSION High b value DW MR might be useful as a complementary tool in preoperative assessment of the histopathological grading of cerebral gliomas. [source] Surface characterization of salmeterol xinafoate powders by inverse gas chromatography at finite coverageJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 3 2005Henry H.Y. Tong Abstract In our previous studies, surface analysis by inverse gas chromatography (IGC) at infinite dilution (zero coverage) was performed on four salmeterol xinafoate (SX) powdered samples, viz, two supercritical CO2 -processed Form I (SX-I) and Form II (SX-II) polymorphs, a commercial granulated SX (GSX) raw material and its micronized product (MSX). Both GSX and MSX are also of the same Form I polymorph. To further probe the differences in surface properties between the samples, the present study has extended the IGC analysis to the finite concentration range of selected energy probes. The adsorption isotherms of the SX samples were constructed using (nonpolar) octane, (polar acidic) chloroform, and (polar basic) tetrahydrofuran as liquid probes. Type II adsorption isotherms with weak knees were observed with each probe for all SX Form I samples. The extents of probe adsorption by the samples at various relative pressures follow the rank order: SX-II,>,GSX,,,MSX,>,SX-I, indicating that the SX-I has fewer high-energy adsorption sites than GSX and MSX. Type III isotherms were observed for SX-II with the two polar probes, indicative of weak adsorbate,adsorbent interactions. The additional information generated shows that IGC analysis at finite coverage is a valuable complementary tool to that at infinite dilution. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 94:695,700, 2005 [source] Waterlogged archaeological wood,chemical changes by conservation and degradationJOURNAL OF RAMAN SPECTROSCOPY, Issue 10 2006M. Christensen Abstract Conservation of waterlogged archaeological wooden artefacts from the Nydam Bog in the southern part of Denmark was investigated by Raman spectroscopy. Two different conservation methods were used: the cellosolve/petroleum method and the polyethylene glycol (PEG)/freeze-drying method. Conservation with cellosolve/petroleum at both room and elevated temperatures was used to preserve archaeological arrows made from pinewood and ash wood. The double bonds in lignin were affected by the warm treatment. Holocellulose in the archaeological wooden arrows had decomposed completely. A band around 180 cm,1 in the R(v)-representation of the low-wavenumber Raman spectrum was used to monitor the presence of water in PEG2000 with a structure like the one in ,free' bulk water. The lignin/PEG2000 relative band intensities were used to make a quantitative estimate of the wood/PEG2000 ratio in a PEG2000 impregnated piece of hardwood. A decreasing degradation of holocellulose was observed from the surface to the centre of an oak piece from the Kolding Cog, built around 1200 A.D. A broad background was observed in the spectra recorded close to the surface of the plank. A similar, very intense, broad background was seen in untreated collapsed ash wood from the Nydam Bog. This broad background, most probably arising from fluorescence, was too intense to allow a Raman spectrum to be seen. In these cases, ATR-FTIR spectroscopy is a valuable complementary tool in studies of waterlogged archaeological wood, confirming that holocellulose degrades more rapidly than lignin. Copyright © 2006 John Wiley & Sons, Ltd. [source] Identification and characterization of 18 novel polymorphic microsatellite makers derived from expressed sequence tags in the Pacific oyster Crassostrea gigasMOLECULAR ECOLOGY RESOURCES, Issue 3 2009C. SAUVAGE Abstract We report the development of 18 new polymorphic microsatellite DNA markers derived from Crassostrea gigas expressed sequences tags. Genotyping of 48 wild adult oysters sampled from Marennes-Oléron bay (France) revealed 12 to 48 alleles per locus. Observed and expected heterozygosity levels ranged from 0.64 to 1 and from 0.77 to 0.97, respectively. The development of these new markers creates a useful complementary tool for population genetics studies, parentage analysis and mapping in Pacific oyster, a species of major aquacultural and ecological importance. [source] Methylprednisolone Exposure in Pediatric Renal Transplant PatientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 6 2006P. Seikku Glucocorticoid (GC) dosing is commonly based on body mass or surface area in children, although the drug effects appear to correlate with steroid exposure, rather than dose. We compared the area under the serum concentration,time curve (AUC) of methylprednisolone (MP) with a recombinant cell bioassay measuring serum glucocorticoid bioactivity (GBA), in prediction of side effects in 16 pediatric patients (5.4,18.4 years of age) 2.0,14.9 years after renal transplantation (TX). They received 0.3 mg/kg of MP orally and timed blood samples were drawn up to 8 h postdose. Serum MP concentrations correlated moderately with GBA (r= 0.65, p < 0.0001) with best linear fit at 6 and 8 h (r= 0.72, 0.79, respectively, p < 0.001). MP-AUCt = 0,8 and GBAt = 6 were significantly greater in patients who gained excessive weight soon after TX. Change in growth after TX was inversely correlated with MP-AUC (r= 0.73, p < 0.05) and GBAt = 6 (r= 0.62, p < 0.05). No correlation of MP-AUC or GBA was found with blood glucose or serum lipid concentrations, glomerular filtration rate, bone mineral density or graft histology. In conclusion, GC exposure varies individually and dosing should be adjusted accordingly to control the adverse effects. GBA might provide a complementary tool for monitoring GC exposure but further studies are needed. [source] Three-dimensional inversion of automatic resistivity profiling dataARCHAEOLOGICAL PROSPECTION, Issue 4 2009Nikos G. Papadopoulos Abstract Geophysical investigations through mobile multi-electrode systems, such as the automatic resistivity profiling (ARP) method, can increase the size of the surveyed areas without jeopardizing the spatial resolution of the survey. The representation of the apparent resistivity data in maps corresponding to the different measuring dipoles is sufficient in most routine applications for outlining the buried archaeological structures. In specific cases where a more quantitative interpretation of the apparent resistivity data is demanded, a three-dimensional resistivity inversion can provide the necessary tool for this purpose. This work investigates the possibilities and limitations of the three-dimensional resistivity inversion in processing the ARP data. A three-dimensional finite element smoothness-constrained inversion algorithm was used. The active constraint balancing (ACB) method was also applied in order to enhance the stability and the resolving power of the inversion procedure. Resistivity models that are commonly encountered in archaeological exploration were used to generate synthetic apparent resistivity data using a three-dimensional finite element forward modelling program. Inversion of the synthetic data showed that the maximum investigation depth of the ARP method is comparable to the length of the larger receiving dipole and cannot exceed the 2,2.5,m for the particular ARP device tested in this work. Archaeological structures buried within this depth range can be effectively mapped, while the resolution of the subsurface structures is related to the data acquisition parameters. The inversion algorithm was also used to reconstruct the three-dimensional resistivity distribution from the ARP data set collected from the Andilly archaeological site in France. The results effectively showed that the three-dimensional inversion can act as a complementary tool in acquiring a more quantitative interpretation model of the buried archaeological features. Copyright © 2009 John Wiley & Sons, Ltd. [source] Complementary roles of prenatal sonography and magnetic resonance imaging in diagnosis of fetal renal anomaliesAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 3 2010Ibrahim A. ABDELAZIM Objectives:, This study was designed to assess the role of magnetic resonance imaging (MRI) in refining the diagnosis of prenatally suspected fetal renal abnormalities following screening ultrasound. Patients and methods:, Twenty pregnant women, with suspected fetal renal abnormality detected during screening ultrasound and more than 14 weeks' gestation, were included in this observational prospective study at Ain Shams University Maternity Hospital from March 2004 to March 2005 after informed consent and after approval of the study protocol by the institute ethics committee. Results:, The MRI could diagnose correctly 10 cases of hydronephrosis, one case of polycystic kidney disease (PCKD), one case of RA, two normal case and two cases of intra-abdominal masses (IA Mass) (16 of 18 cases). The prenatal ultrasound could diagnose correctly eight cases of hydronephrosis, one case of PCKD, one case of renal agenesis, one case of multicystic kidney disease and one case of IA Mass (12 of 18 cases). The prenatal ultrasound and MRI gave different diagnoses in eight cases and gave the same diagnosis in 12 cases. The MRI could diagnose the aetiology of congenital renal cysts in 10 of the 20 studied cases (50%). Conclusion:, Magnetic resonance imaging can be used as a complementary tool in the assessment of sonographically suspected fetal renal anomalies. [source] Electrospray-ionization mass spectrometry as a tool for fast screening of protein structural propertiesBIOTECHNOLOGY JOURNAL, Issue 1 2009Rita Grandori Abstract Since the early 1990s, electrospray-ionization mass spectrometry (ESI-MS) has encountered growing interest as a complementary tool to established biochemical and biophysical methods for investigating protein structure and conformation. Nowadays, applications of ESI-MS to protein investigation span from the area of analytical biochemistry to that of structural biology. This review focuses on applications of this technique to the analysis of protein conformational properties and molecular interactions, underscoring their possible relevance for molecular biotechnology, although representing a still very young field. An introductive section presents the major issues related to theoretical and technical aspects of ESI-MS under non-denaturing conditions. Examples from our work and from the literature illustrate which kind of information can be obtained concerning key issues in biotechnology such as stability and aggregation of proteins under both near-native and challenging conditions, and interactions with other proteins, ligands and cofactors. [source] Identification of a ligand for IgG-Fc derived from a soluble peptide library based on fusion proteins secreted by S. cerevisiaeBIOTECHNOLOGY JOURNAL, Issue 6 2007Christa Mersich Abstract Biological libraries are important tools in the development of new peptide-based compounds. Here, we describe the use of a soluble peptide library system as a complementary tool in the field of ligand development. Random peptides were expressed in S. cerevisiae as carboxy-terminal extensions of the eukaryotic initiation factor 5a (eIF5a) and secreted into the culture supernatant. Expression and screening of this library were performed in a microwell format. As an example of this versatile approach, we describe the identification of a ligand for the human IgG-Fc fragment. Ligands binding IgG-Fc show great potential in a wide variety of applications including development of therapeutics, streamlining the large-scale purification of antibodies, and applications in diagnostic tests. We demonstrated the utility of this system. After screening only 6160 clones, we identified a ligand with the peptide sequence of TRRRTCSPPTWPRARARSTPSGCSSTGPSANRG. An affinity constant of 3.9 x 105 M -1 was determined by a biosensor method. Handling and maintenance of this library is conceptually simple and highly applicable for automated high-throughput systems. [source] Comprehensive comparison of FISH, RT-PCR, and RQ-PCR for monitoring the BCR-ABL gene after hematopoietic stem cell transplantation in CMLEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5 2002Yoo-Jin Kim Abstract: The reverse transcriptase-polymerase chain reaction (RT-PCR) was compared with fluorescence in situ hybridization (FISH) and real-time quantitative RT-PCR (RQ-PCR) for minimal residual disease (MRD) monitoring in 266 post-transplant bone marrow samples from 78 patients with chronic myelogenous leukemia (CML). The sensitivities of FISH to BCR-ABL positive samples determined by first-round (1st) RT-PCR, second-round (2nd) RT-PCR, and RQ-PCR were 64.2%, 25.8%, and 20.7%, respectively. The BCR-ABL/ABL ratio by RQ-PCR had a mean of 0.000,13 in the 1st RT-PCR-negative samples and 1.42 in the 1st RT-PCR-positive samples (P<0.001), and means of 0.000,39 and 0.51 in the 2nd RT-PCR-negative and -positive samples (P< 0.001). The mean ratios of BCR-ABL/ABL by RQ-PCR were significantly different in N/N (1st/2nd RT-PCR) or N/P and P/P (P<0.001), but not in N/N and N/P, which showed that the discriminative power of RQ-PCR is confined to the 1st RT-PCR level. In this respect, monitoring of the 1st RT-PCR might be useful for estimating normalized BCR-ABL levels after transplantation. Nested RT-PCR was of limited use, as RQ-PCR quantified the BCR-ABL transcripts in 60 (91%) of 66 samples determined to be negative by 2nd RT-PCR. FISH was significantly correlated with RQ-PCR in FISH-positive samples (n=24, r=0.79, P=0.001). An increase of FISH preceded that of RQ-PCR in a few cases with molecular relapse. By analyzing a large number of samples post-transplant, we found that RQ-PCR might be the most useful assay for MRD monitoring; however, FISH and RT-PCR were found to be useful complementary tools. [source] High mass accuracy in-source collision-induced dissociation tandem mass spectrometry and multi-step mass spectrometry as complementary tools for fragmentation studies of quaternary ammonium herbicidesJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 8 2004Oscar Núñez Abstract Fragmentation studies using both an ion-trap mass analyzer and a hybrid quadrupole time-of-flight (Q-TOF) mass spectrometer were performed in order to establish the fragmentation pathways of organic molecules. A general strategy combining MSn data (n = 1,4) in an ion-trap analyzer with tandem mass spectrometry and in-source collision-induced dissociation tandem mass spectrometry (CID MS/MS) in a Q-TOF instrument was applied. The MSn data were used to propose a tentative fragmentation pathway following genealogical relationships. When several assignments were possible, MS/MS and in-source CID MS/MS (Q-TOF) allowed the elemental compositions of the fragments to be confirmed. Quaternary ammonium herbicides (quats) were used as test compounds and their fragmentation pathways were established. The elemental composition of the fragments was confirmed using the TOF analyzer with relative errors <0.0023 Da. Some fragments previously reported in the literature were reassigned taking advantage of the high mass resolution and accuracy of the Q-TOF instrument, which made it possible to solve losses where nitrogen was involved. Copyright © 2004 John Wiley & Sons, Ltd. [source] On cross-correlating weak lensing surveysMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2005Dipak Munshi ABSTRACT The present generation of weak lensing surveys will be superseded by surveys run from space with much better sky coverage and high level of signal-to-noise ratio, such as the Supernova/Acceleration Probe (SNAP). However, removal of any systematics or noise will remain a major cause of concern for any weak lensing survey. One of the best ways of spotting any undetected source of systematic noise is to compare surveys that probe the same part of the sky. In this paper we study various measures that are useful in cross-correlating weak lensing surveys with diverse survey strategies. Using two different statistics , the shear components and the aperture mass , we construct a class of estimators which encode such cross-correlations. These techniques will also be useful in studies where the entire source population from a specific survey can be divided into various redshift bins to study cross-correlations among them. We perform a detailed study of the angular size dependence and redshift dependence of these observables and of their sensitivity to the background cosmology. We find that one-point and two-point statistics provide complementary tools which allow one to constrain cosmological parameters and to obtain a simple estimate of the noise of the survey. [source] Genome-wide scan for bovine twinning rate QTL using linkage disequilibriumANIMAL GENETICS, Issue 3 2009E.-S. Kim Summary Twinning is a complex trait with negative impacts on health and reproduction, which cause economic loss in dairy production. Several twinning rate quantitative trait loci (QTL) have been detected in previous studies, but confidence intervals for QTL location are broad and many QTL are unreplicated. To identify genomic regions or genes associated with twinning rate, QTL analysis based on linkage combined with linkage disequilibrium (LLD) and individual marker associations was conducted across the genome using high-throughput single nucleotide polymorphism (SNP) genotypes. A total of 9919 SNP markers were genotyped with 200 sires and sons in 19 half-sib North American Holstein dairy cattle families. After SNPs were genotyped, informative markers were selected for genome-wide association tests and QTL searches. Evidence for twinning rate QTL was found throughout the genome. Thirteen markers significantly associated with twinning rate were detected on chromosomes 2, 5 and 14 (P < 2.3 × 10,5). Twenty-six regions on fourteen chromosomes were identified by LLD analysis at P < 0.0007. Seven previously reported ovulation or twinning rate QTL were supported by results of single marker association or LLD analyses. Single marker association analysis and LLD mapping were complementary tools for the identification of putative QTL in this genome scan. [source] Assessing SNP markers for assigning individuals to cattle populationsANIMAL GENETICS, Issue 1 2009R. Negrini Summary The effectiveness of single nucleotide polymorphisms (SNPs) for the assignment of cattle to their source breeds was investigated by analysing a panel of 90 SNPs assayed on 24 European breeds. Breed assignment was performed by comparing the Bayesian and frequentist methods implemented in the structure 2.2 and geneclass 2 software programs. The use of SNPs for the reallocation of known individuals to their breeds of origin and the assignment of unknown individuals was tested. In the reallocation tests, the methods implemented in structure 2.2 performed better than those in geneclass 2, with 96% vs. 85% correct assignments respectively. In contrast, the methods implemented in geneclass 2 showed a greater correct assignment rate in allocating animals treated as unknowns to a reference dataset (62% vs. 51% and 80% vs. 65% in field tests 1 and 2 respectively). These results demonstrate that SNPs are suitable for the assignment of individuals to reference breeds. The results also indicate that structure 2.2 and geneclass 2 can be complementary tools to assess breed integrity and assignment. Our findings also stress the importance of a high-quality reference dataset in allocation studies. [source] Progenitor cells in liver regeneration: molecular responses controlling their activation and expansion,APMIS, Issue 11-12 2005ERIC SANTONI-RUGIU Although normally quiescent, the adult mammalian liver possesses a great capacity to regenerate after different types of injuries in order to restore the lost liver mass and ensure maintenance of the multiple liver functions. Major players in the regeneration process are mature residual cells, including hepatocytes, cholangiocytes and stromal cells. However, if the regenerative capacity of mature cells is impaired by liver-damaging agents, hepatic progenitor cells are activated and expand into the liver parenchyma. Upon transit amplification, the progenitor cells may generate new hepatocytes and biliary cells to restore liver homeostasis. In recent years, hepatic progenitor cells have been the subject of increasing interest due to their therapeutic potential in numerous liver diseases as alternative or supportive/complementary tools to liver transplantation. While the first investigations on hepatic progenitor cells have focused on their origin and phenotypic characterization, recent attention has focused on the influence of the hepatic microenvironment on their activation and proliferation. This microenvironment comprises the extracellular matrix, epithelial and non-epithelial resident liver cells, and recruited inflammatory cells as well as the variety of growth-modulating molecules produced and/or harboured by these elements. The cellular and molecular responses to different regenerative stimuli seem to depend on the injury inflicted and consequently on the molecular microenvironment created in the liver by a certain insult. This review will focus on molecular responses controlling activation and expansion of the hepatic progenitor cell niche, emphasizing similarities and differences in the microenvironments orchestrating regeneration by recruitment of progenitor cell populations or by replication of mature cells. [source] | |||||||||||||||||||