904 resultados para complex analysis


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Streptokinase, a 47-kDa protein isolated and secreted by most group A, C and G ß-hemolytic streptococci, interacts with and activates human protein plasminogen to form an active complex capable of converting other plasminogen molecules to plasmin. Our objective was to compare five streptokinase formulations commercially available in Brazil in terms of their activity in the in vitro tests of euglobulin clot formation and of the hydrolysis of the plasmin-specific substrate S-2251™. Euglobulin lysis time was determined using a 96-well microtiter plate. Initially, human thrombin (10 IU/ml) and streptokinase were placed in individual wells, clot formation was initiated by the addition of plasma euglobulin, and turbidity was measured at 340 nm every 30 s. In the second assay, plasminogen activation was measured using the plasmin-specific substrate S-2251™. Streptase™ was used as the reference formulation because it presented the strongest fibrinolytic activity in the euglobulin lysis test. The Unitinase™ and Solustrep™ formulations were the weakest, showing about 50% activity compared to the reference formulation. All streptokinases tested activated plasminogen but significant differences were observed. In terms of total S-2251™ activity per vial, Streptase™ (75.7 ± 5.0 units) and Streptonase™ (94.7 ± 4.6 units) had the highest activity, while Unitinase™ (31.0 ± 2.4 units) and Strek™ (32.9 ± 3.3 units) had the weakest activity. Solustrep™ (53.3 ± 2.7 units) presented intermediate activity. The variations among the different formulations for both euglobulin lysis test and chromogenic substrate hydrolysis correlated with the SDS-PAGE densitometric results for the amount of 47-kDa protein. These data show that the commercially available clinical streptokinase formulations vary significantly in their in vitro activity. Whether these differences have clinical implications needs to be investigated.

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Membranous nephropathy (MN), characterized by the presence of diffuse thickening of the glomerular basement membrane and subepithelial in situimmune complex disposition, is the most common cause of idiopathic nephrotic syndrome in adults, with an incidence of 5-10 per million per year. A number of studies have confirmed the relevance of several experimental insights to the pathogenesis of human MN, but the specific biomarkers of MN have not been fully elucidated. As a result, our knowledge of the alterations in histone methylation in MN is unclear. We used chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) to analyze the variations in a methylated histone (H3K9me3) in peripheral blood mononuclear cells from 10 MN patients and 10 healthy subjects. There were 108 genes with significantly different expression in the MN patients compared with the normal controls. In MN patients, significantly increased activity was seen in 75 H3K9me3 genes, and decreased activity was seen in 33, compared with healthy subjects. Five positive genes, DiGeorge syndrome critical region gene 6 (DGCR6), sorting nexin 16 (SNX16), contactin 4 (CNTN4), baculoviral IAP repeat containing 3 (BIRC3), and baculoviral IAP repeat containing 2 (BIRC2), were selected and quantified. There were alterations of H3K9me3 in MN patients. These may be candidates to help explain pathogenesis in MN patients. Such novel findings show that H3K9me3 may be a potential biomarker or promising target for epigenetic-based MN therapies.

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In this study, biomarkers and transcriptional factor motifs were identified in order to investigate the etiology and phenotypic severity of Down syndrome. GSE 1281, GSE 1611, and GSE 5390 were downloaded from the gene expression ominibus (GEO). A robust multiarray analysis (RMA) algorithm was applied to detect differentially expressed genes (DEGs). In order to screen for biological pathways and to interrogate the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database, the database for annotation, visualization, and integrated discovery (DAVID) was used to carry out a gene ontology (GO) function enrichment for DEGs. Finally, a transcriptional regulatory network was constructed, and a hypergeometric distribution test was applied to select for significantly enriched transcriptional factor motifs. CBR1, DYRK1A, HMGN1, ITSN1, RCAN1, SON, TMEM50B, and TTC3 were each up-regulated two-fold in Down syndrome samples compared to normal samples; of these, SON and TTC3 were newly reported. CBR1, DYRK1A, HMGN1, ITSN1, RCAN1, SON, TMEM50B, and TTC3 were located on human chromosome 21 (mouse chromosome 16). The DEGs were significantly enriched in macromolecular complex subunit organization and focal adhesion pathways. Eleven significantly enriched transcription factor motifs (PAX5, EGR1, XBP1, SREBP1, OLF1, MZF1, NFY, NFKAPPAB, MYCMAX, NFE2, and RP58) were identified. The DEGs and transcription factor motifs identified in our study provide biomarkers for the understanding of Down syndrome pathogenesis and progression.

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Cardioplegic reperfusion during a long term ischemic period interrupts cardiac surgery and also increases cellular edema due to repeated solution administration. We reviewed the clinical experiences on myocardial protection of a single perfusion with histidine-tryptophan-ketoglutarate (HTK) for high-risk patients with severe pulmonary arterial hypertension associated with complex congenital heart disease. This retrospective study included 101 high-risk patients undergoing arterial switch operation between March 2001 and July 2012. We divided the cohort into two groups: HTK group, myocardial protection was carried out with one single perfusion with HTK solution; and St group, myocardial protection with conventional St. Thomas' crystalloid cardioplegic solution. The duration of cardiopulmonary bypass did not differ between the two groups. The mortality, morbidity, ICU stay, post-operative hospitalization time, and number of transfusions in HTK group were lower than those in St group (P<0.05). Univariate and multivariate analysis showed that HTK is a statistically significant independent predictor of decreased early mortality and morbidity (P<0.05). In conclusion, HTK solution seems to be an effective and safe alternative to St. Thomas' solution for cardioplegic reperfusion in high-risk patients with complex congenital heart disease.

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Coffee is one of the most appreciated drinks in the world. Coffee ground is obtained from the fruit of a small plant that belongs to the genus Coffea. Coffea arabica and Coffea canephora robusta are the two most commercially important species. They are more commonly known as arabica and robusta, respectively. Two-thirds of Coffea arabica plants are grown in South and Central America, and Eastern Africa - the place of origin for this coffee species. Contamination by microorganisms has been a major matter affecting coffee quality in Brazil, mainly due to the harvesting method adopted. Brazilian harvests are based on fruits collected from the ground mixed with those that fall on collection cloths. As the Bacillus cereus bacterium frequently uses the soil as its environmental reservoir, it is easily capable of becoming a contaminant. This study aimed to evaluate the contamination and potential of B. cereus enterotoxin genes encoding the HBL and NHE complexes, which were observed in strains of ground and roasted coffee samples sold in Rio de Janeiro. The PCR (Polymerase Chain Reaction) results revealed high potential of enterotoxin production in the samples. The method described by Speck (1984) was used for the isolation of contaminants. The investigation of the potential production of enterotoxins through isolates of the microorganism was performed using the B. cereus enterotoxin Reverse Passive Latex Agglutination test-kit (BCET-RPLA, Oxoid), according to the manufacturer's instructions. The potential of enterotoxin production was investigated using polymerase chain reaction (PCR) methods for hblA, hblD and hblC genes (encoding hemolysin HBL) and for nheA, nheB and nheC genes (encoding non-hemolytic enterotoxin - NHE). Of all the 17 strains, 100% were positive for at least 1 enterotoxin gene; 52.9% (9/17) were positive for the 3 genes encoding the HBL complex; 35.3% (6/17) were positive for the three NHE encoding genes; and 29.4% (5/17) were positive for all enterotoxic genes.

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Studying testis is complex, because the tissue has a very heterogeneous cell composition and its structure changes dynamically during development. In reproductive field, the cell composition is traditionally studied by morphometric methods such as immunohistochemistry and immunofluorescence. These techniques provide accurate quantitative information about cell composition, cell-cell association and localization of the cells of interest. However, the sample preparation, processing, staining and data analysis are laborious and may take several working days. Flow cytometry protocols coupled with DNA stains have played an important role in providing quantitative information of testicular cells populations ex vivo and in vitro studies. Nevertheless, the addition of specific cells markers such as intracellular antibodies would allow the more specific identification of cells of crucial interest during spermatogenesis. For this study, adult rat Sprague-Dawley rats were used for optimization of the flow cytometry protocol. Specific steps within the protocol were optimized to obtain a singlecell suspension representative of the cell composition of the starting material. Fixation and permeabilization procedure were optimized to be compatible with DNA stains and fluorescent intracellular antibodies. Optimization was achieved by quantitative analysis of specific parameters such as recovery of meiotic cells, amount of debris and comparison of the proportions of the various cell populations with already published data. As a result, a new and fast flow cytometry method coupled with DNA stain and intracellular antigen detection was developed. This new technique is suitable for analysis of population behavior and specific cells during postnatal testis development and spermatogenesis in rodents. This rapid protocol recapitulated the known vimentin and γH2AX protein expression patterns during rodent testis ontogenesis. Moreover, the assay was applicable for phenotype characterization of SCRbKO and E2F1KO mouse models.

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Avidins (Avds) are homotetrameric or homodimeric glycoproteins with typically less than 130 amino acid residues per monomer. They form a highly stable, non-covalent complex with biotin (vitamin H) with Kd = 10-15 M (for chicken Avd). The best-studied Avds are the chicken Avd from Gallus gallus and streptavidin from Streptomyces avidinii, although other Avd studies have also included Avds from various origins, e.g., from frogs, fishes, mushrooms and from many different bacteria. Several engineered Avds have been reported as well, e.g., dual-chain Avds (dcAvds) and single-chain Avds (scAvds), circular permutants with up to four simultaneously modifiable ligand-binding sites. These engineered Avds along with the many native Avds have potential to be used in various nanobiotechnological applications. In this study, we made a structure-based alignment representing all currently available sequences of Avds and studied the evolutionary relationship of Avds using phylogenetic analysis. First, we created an initial multiple sequence alignment of Avds using 42 closely related sequences, guided by the known Avd crystal structures. Next, we searched for non-redundant Avd sequences from various online databases, including National Centre for Biotechnology Information and the Universal Protein Resource; the identified sequences were added to the initial alignment to expand it to a final alignment of 242 Avd sequences. The MEGA software package was used to create distance matrices and a phylogenetic tree. Bootstrap reproducibility of the tree was poor at multiple nodes and may reflect on several possible issues with the data: the sequence length compared is relatively short and, whereas some positions are highly conserved and functional, others can vary without impinging on the structure or the function, so there are few informative sites; it may be that periods of rapid duplication have led to paralogs and that the differences among them are within the error limit of the data; and there may be other yet unknown reasons. Principle component analysis applied to alternative distance data did segregate the major groups, and success is likely due to the multivariate consideration of all the information. Furthermore, based on our extensive alignment and phylogenetic analysis, we expressed two novel Avds, lacavidin from Lactrodectus Hesperus, a western black widow spider, and hoefavidin from Hoeflea phototrophica, an aerobic marine bacterium, the ultimate aim being to determine their X-ray structures. These Avds were selected because of their unique sequences: lacavidin has an N-terminal Avd-like domain but a long C-terminal overhang, whereas hoefavidin was thought to be a dimeric Avd. Both these Avds could be used as novel scaffolds in biotechnological applications.

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The purpose of this thesis was to study change management and find out how the theory applies to practise with the help of studying an organizational change process. The goal was to investigate the different ways of the change management and how those could be utilized in practise. The purpose was also to see what kind of tools and information packages for change management the company involved has developed and taken in to use and check if these could have been utilized in the change process studied in this thesis. This thesis was established by studying the theory of change management and interviewing the people involved in the organizational change and the stakeholders. The questions were formed in line with the change management theory. The main theory used was John P. Kotter’s Eight Steps of Change. The study revealed valuable details about change processes in real life and concrete improvement ideas were recognized from the interviews. Overall the people were quite happy with the outcome of the change process. There were also some failures identified in this change process. Most probably those can be avoided in the future if people planning the change are familiar with the company’s new information packages and tools for change management. Change management is a complex area that is still today quite often forgotten by companies. Effective change management can give a huge competitive advantage for a company. Acknowledging that change process is always complex and not easy is already a good step forward in handling change processes. All changes need change management and understanding the way people react on change. A good and efficient change management is the key to make the change process smooth and easier for the people involved.

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Outsourcing and offshoring or any combinations of these have not just become a popular phenomenon, but are viewed as one of the most important management strategies due to the new possibilities from globalization. They have been seen as a possibility to save costs and improve customer service. Executing offshoring and offshore outsourcing successfully can be more complex than initially expected. Potential cost savings resulting from of offshoring and offshore outsourcing are often based on lower manufacturing costs. However, these benefits might be conflicted by a more complex supply chain with service level challenges that can respectively increase costs. Therefore analyzing the total cost effects of offshoring and outsourcing is necessary. The aim of this Master´s Thesis was to to construct a total cost model using academic literature to calculate the total costs and analyze the reasonability of offshoring and offshore outsourcing production of a case company compared to insourcing production. The research data was mainly quantitative and collected mainly from the case company past sales and production records. In addition management level interviews from the case company were conducted. The information from these interviews was used for the qualification of the necessary quantitative data and adding supportive information that could not be gathered from the quantitative data. Both data collection and analysis were guided by a theoretical frame of reference that was based on academic literature concerning offshoring and outsourcing, statistical calculation of demand and total costs. The results confirm the theories that offshoring and offshore outsourcing would reduce total costs as both offshoring and offshore outsourcing options result in lower total annual costs than insourcing mainly due to lower manufacturing costs. However, increased demand uncertainty would make the alternative of offshore outsourcing more risky and difficult to manage. Therefore when assessing the overall impact of the alternatives, offshoring is the most preferable option. As the main cost savings in offshore outsourcing came from lower manufacturing costs, more specifically labour costs, the logistics costs in this case company did not have an essential effect in total costs. The management should therefore pay attention initially to manufacturing costs and then logistics costs when choosing the best production sourcing option for the company.

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In this thesis the process of building a software for transport accessibility analysis is described. The goal was to create a software which is easy to distribute and simple to use for the user without particular background in the field of the geographical data analysis. It was shown that existing tools do not suit for this particular task due to complex interface or significant rendering time. The goal was accomplished by applying modern approaches in the process of building web applications such as maps based on vector tiles, FLUX architecture design pattern and module bundling. It was discovered that vector tiles have considerable advantages over image-based tiles such as faster rendering and real-time styling.

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ZnF2, CdF2, and CUF2 have been adsorbed onto the surface of montmorillonite K10, and the infrared and 19F, 27 AI, and 29Si MAS NMR spectra of the reagents over a range of loadings have been obtained. CUF2 was observed to attack the Si02 layer and form the complex CuSiF6, Zn F2 tends to attack the aluminium oxide layer, in which Zn isomorphously replaces AI, and forms AIF3 and AIF4 - complexes. All the spectroscopic evidence ruled out the formation of any AI-F and/or Si-F free species as CdF2 is adsorbed on the surface of montmorillonite K10. The reactivity of MF2-K10 reagents towards Friedel-Crafts benzylation of benzene with benzyl chloride varied from one reagent to another. ZnF2-K10 was observed to be the most reactive and CUF2 was the least reactive.

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The mechanism whereby cytochrome £ oxidase catalyses elec-. tron transfer from cytochrome £ to oxygen remains an unsolved problem. Polarographic and spectrophotometric activity measurements of purified, particulate and soluble forms of beef heart mitochondrial cytochrome c oxidase presented in this thesis confirm the following characteristics of the steady-state kinetics with respect to cytochrome £: (1) oxidation of ferrocytochrome c is first order under all conditions. -(2) The relationship between sustrate concentration and velocity is of the Michaelis-Menten type over a limited range of substrate. concentrations at high ionic strength. (3) ~he reaction rate is independent from oxygen concentration until very low levels of oxygen. (4) "Biphasic" kinetic plots of enzyme activity as a function of substrate concentration are found when the range of cytochrome c concentrations is extended; the biphasicity ~ is more apparent in low ionic strength buffer. These results imply two binding sites for cytochrome £ on the oxidase; one of high affinity and one of low affinity with Km values of 1.0 pM and 3.0 pM, respectively, under low ionic strength conditions. (5) Inhibition of the enzymic rate by azide is non-c~mpetitive with respect to cytochrome £ under all conditions indicating an internal electron transfer step, and not binding or dissociation of £ from the enzyme is rate limiting. The "tight" binding of cytochrome '£ to cytochrome c oxidase is confirmed in column chromatographic experiments. The complex has a cytochrome £:oxidase ratio of 1.0 and is dissociated in media of high ionic strength. Stopped-flow spectrophotometric studies of the reduction of equimolar mixtures and complexes of cytochrome c and the oxidase were initiated in an attempt to assess the functional relevance of such a complex. Two alternative routes -for reduction of the oxidase, under conditions where the predominant species is the £ - aa3 complex, are postulated; (i) electron transfer via tightly bound cytochrome £, (ii) electron transfer via a small population of free cytochrome c interacting at the "loose" binding site implied from kinetic studies. It is impossible to conclude, based on the results obtained, which path is responsible for the reduction of cytochrome a. The rate of reduction by various reductants of free cytochrome £ in high and low ionic strength and of cytochrome £ electrostatically bound to cytochrome oxidase was investigated. Ascorbate, a negatively charged reagent, reduces free cytochrome £ with a rate constant dependent on ionic strength, whereas neutral reagents TMPD and DAD were relatively unaffected by ionic strength in their reduction of cytochrome c. The zwitterion cysteine behaved similarly to uncharged reductants DAD and TI~PD in exhibiting only a marginal response to ionic strength. Ascorbate reduces bound cytochrome £ only slowly, but DAD and TMPD reduce bound cytochrome £ rapidly. Reduction of cytochrome £ by DAD and TMPD in the £ - aa3 complex was enhanced lO-fold over DAD reduction of free £ and 4-fold over TMPD reduction of free c. Thus, the importance of ionic strength on the reactivity of cytochrome £ was observed with the general conclusion being that on the cytochrome £ molecule areas for anion (ie. phosphate) binding, ascorbate reduction and complexation to the oxidase overlap. The increased reducibility for bound cytochrome £ by reductants DAD and TMPD supports a suggested conformational change of electrostatically bound c compare.d to free .£. In addition, analysis of electron distribution between cytochromes £ and a in the complex suggest that the midpotential of cytochrome ~ changes with the redox state of the oxidase. Such evidence supports models of the oxidase which suggest interactions within the enzyme (or c - enzyme complex) result in altered midpoint potentials of the redox centers.

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The Paint Lake Deformation Zone (PLDZ), located within the Superior Province of Canada, demarcates a major structural and lithological break between the Onaman-Tashota Terrane to the north and the Beardmore-Geraldton Belt to the south. The PLDZ is an east-west trending lineament, approximately 50 km in length and up to 1 km in width, comprised of an early ductile component termed the Paint Lake Shear Zone and a late brittle component known as the Paint Lake Fault. Structures associated with PLDZ development including S-, C- and C'-fabrics, stretching lineations, slickensides, C-C' intersection lineations, Z-folds and kinkbands indicate that simple shear deformation dominated during a NW-SE compressional event. Movement along the PLDZ was in a dextral sense consisting of an early differential motion with southside- down and a later strike-slip motion. Although the locus of the PLDZ may in part be lithologically controlled, mylonitization which accompanied shear zone development is not dependent on the lithological type. Conglomerate, intermediate and mafic volcanic units exhibit similar mesoscopic and microscopic structures where transected by the PLDZ. Field mapping, supported by thin section analysis, defines five strain domains increasing in intensity of deformation from shear zone boundary to centre. A change in the dominant microstructural deformation mechanism from dislocation creep to diffusion creep is observed with increasing strain during mylonitization. C'-fabric development is temporally associated with this change. A decrease in the angular relationship between C- and C'-fabrics is observed upon attaining maximum strain intensity. Strain profiling of the PLDZ demonstrates the presence of an outer primary strain gradient which exhibits a simple profile and an inner secondary strain gradient which exhibits a more complex profile. Regionally metamorphosed lithologies of lower greenschist facies outside the PLDZ were subjected to retrograde metamorphism during deformation within the PLDZ.

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This project was undertaken because of a need to analyse concepts in social science more specifically and sequence them more carefully in a social science program. Concepts have been identified vaguely on many curriculum documents or left in isolation from each other when they are specifically identified. The project's aim was to identify a method for analysing concepts and sequencing their teaching on some rational basis. Once the method for analysing concepts was identified a questionnaire was designed and administered to a random sample of students at the grade three, five and eight levels. The questionnaire attempted to measure their comprehension of specific social science concepts at several levels which became progressively more complex. The major hypothesis was that there would be a direct correlation between age and achievement on the questionnaire. The raw scores were seriated and correlated with the ages of the students using the rankdifference- squared method. For the majority of areas tested it was found that there was a significant correlation between age and achievement on the questionnaire. Variation in the correlation coefficients generated suggests that comprehension of social science concepts is not simply a function of age but is probably a function of several inter-related factors such as reading ability, skill in Basic Thinking Skills and age. Thirty students completed each test. There were three tests in the questionnaire.

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An energy theory is formulated for the rotational energy levels in a p-complex Rydberg state of an asymmetric top molecule of symmetry C2v. The effective Hamiltonian used consists of the usual rigid rotor Hamiltonian augmented with terms representing electronic spin and orbital angular momentum effects. Criteria for assigning symmetry species to the rotational energy levels, following Houganfs scheme that uses the full molecular group,are established and given in the form of a table. This is particularly suitable when eigenvectors are calculated on a digital computer. Also, an intensity theory for transitions to the Rydberg p-complex singlet states is presented and selection rules in terms of symmetry species of energy states are established. Finally, applications to HpO and DpO are given.