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991.
992.
Yun Xu Sarah J. Dixon Richard G. Brereton Helena A. Soini Milos V. Novotny Karlheinz Trebesius Ingrid Bergmaier Elisabeth Oberzaucher Karl Grammer Dustin J. Penn 《Metabolomics : Official journal of the Metabolomic Society》2007,3(4):427-437
Several studies have shown that microbial action is responsible for many compounds responsible for human odour. In this paper,
we compare the pattern of microbial profiles and that of chemical profiles of human axillary odour by using multivariate pattern
matching techniques. Approximately 200 subjects from Carinthia, Austria, participated in the study. The microbial profiles
were represented by denaturing gradient gel electrophoresis (DGGE) analysis and the axillary odour profiles were determined
in the sweat samples collected by a stir-bar sampling device and analysed by gas chromatography/mass spectrometry (GC/MS).
Both qualitative and quantitative distance metrics were used to construct dissimilarity matrices between samples which were
then used to represent the patterns of these two types of profiles. The distance matrices were then compared by using the
Mantel test and the Procrustean test. The results show that on the overall dataset there is no strong correlation between
microbial and chemical profiles. When the data are split into family groups, correlations vary according to family with a
range of estimated p values from 0.00 to 0.90 that the null hypothesis (no correlation) holds. When 32 subjects who followed four basic rules
of behaviour were selected, the estimated p-values are 0.00 using qualitative and <0.01 using quantitative distance metrics, suggesting excellent evidence that there
is a connection between the microbial and chemical signature. 相似文献
993.
Bernardo R Tura Helena F Martino Luis H Gowdak Ricardo Ribeiro dos Santos Hans F Dohmann José E Krieger Gilson Feitosa Fábio Vilas-Boas Sérgio A Oliveira Suzana A Silva Augusto Z Bozza Radovan Borojevic Antonio C Campos de Carvalho 《Trials》2007,8(1):1-4
Background
Cardiovascular diseases are the major cause of death in the world. Current treatments have not been able to reverse this scenario, creating the need for the development of new therapies. Cell therapies have emerged as an alternative for cardiac diseases of distinct causes in experimental animal studies and more recently in clinical trials.Method/Design
We have designed clinical trials to test for the efficacy of autologous bone marrow derived mononuclear cell therapies in four different cardiopathies: acute and chronic ischemic heart disease, and Chagasic and dilated cardiomyopathy. All trials are multicenter, randomized, double-blind and placebo controlled. In each trial 300 patients will be enrolled and receive optimized therapy for their specific condition. Additionally, half of the patients will receive the autologous bone marrow cells while the other half will receive placebo (saline with 5% autologous serum). For each trial there are specific inclusion and exclusion criteria and the method for cell delivery is intramyocardial for the chronic ischemic heart disease and intracoronary for all others. Primary endpoint for all studies will be the difference in ejection fraction (determined by Simpson's rule) six and twelve months after intervention in relation to the basal ejection fraction. The main hypothesis of this study is that the patients who receive the autologous bone-marrow stem cell implant will have after a 6 month follow-up a mean increase of 5% in absolute left ventricular ejection fraction in comparison with the control group.Discussion
Many phase I clinical trials using cell therapy for cardiac diseases have already been performed. The few randomized studies have yielded conflicting results, rendering necessary larger well controlled trials to test for efficacy of cell therapies in cardiopathies. The trials registration numbers at the NIH registry are the following: Chagasic cardiomyopathy (NCT00349271), dilated cardiomyopathy (NCT00333827), acute myocardial infarction (NCT00350766) and Chronic Ischemic Heart Disease (NCT00362388). 相似文献994.
Ferron SR Andreu-Agullo C Mira H Sanchez P Marques-Torrejon MA Farinas I 《Nature protocols》2007,2(4):849-859
We describe a protocol developed/modified by our group for the ex vivo and in vivo assessment of the response to a soluble factor of murine neural stem cells from the adult sub-ventricular zone (SVZ). The procedure includes several experimental options that can be used either independently or in combination. Potential factor effects on self-renewal, survival and proliferation are assayed by means of neurosphere cultures, with the factor administered directly in vitro to the culture plates (Step 1) or infused in vivo immediately before tissue dissociation (Step 3). We also use bromodeoxiuridine (BrdU) retention to label slowly dividing cells in vivo and subsequently perform two different types of experiments. In one set of experiments, the factor is added to primary cultures of stem cells obtained from the BrdU-pulsed animals and effects are tested on label-retaining cells after immunocytochemistry (Step 2). In another set, prolonged intraventricular infusion of the factor in BrdU-pulsed animals is followed by immunohistochemical analysis of BrdU labeling in the intact SVZ (Step 4). The minimum estimated time for the full combined procedure is 45 d. 相似文献
995.
The growing number of applications to determine the stoichiometry, interactions and even subunit architecture of protein complexes from mass spectra suggests that some general guidelines can now be proposed. In this protocol, we describe the necessary steps required to maintain interactions between subunits in the gas phase. We begin with the preparation of suitable solutions for electrospray (ES) and then consider the transmission of complexes through the various stages of the mass spectrometer until their detection. Subsequent steps are also described, including the dissociation of these complexes into multiple subcomplexes for generation of interaction networks. Throughout we highlight the critical experimental factors that determine success. Overall, we develop a generic protocol that can be carried out using commercially available ES mass spectrometers without extensive modification. 相似文献
996.
Differential scanning fluorimetry (DSF) is a rapid and inexpensive screening method to identify low-molecular-weight ligands that bind and stabilize purified proteins. The temperature at which a protein unfolds is measured by an increase in the fluorescence of a dye with affinity for hydrophobic parts of the protein, which are exposed as the protein unfolds. A simple fitting procedure allows quick calculation of the transition midpoint; the difference in the temperature of this midpoint in the presence and absence of ligand is related to the binding affinity of the small molecule, which can be a low-molecular-weight compound, a peptide or a nucleic acid. DSF is best performed using a conventional real-time PCR instrument. Ligand solutions from a storage plate are added to a solution of protein and dye, distributed into the wells of the PCR plate and fluorescence intensity measured as the temperature is raised gradually. Results can be obtained in a single day. 相似文献
997.
998.
Kanerva A Raki M Ranki T Särkioja M Koponen J Desmond RA Helin A Stenman UH Isoniemi H Höckerstedt K Ristimäki A Hemminki A 《The journal of gene medicine》2007,9(1):3-9
BACKGROUND: Adenoviruses can cause severe toxicity in immunocompromised individuals. Although clinical trials have confirmed the potency and safety of selectively oncolytic adenoviruses for treatment of advanced cancers, increasingly effective agents could result in more toxicity and therefore it would be useful if replication could be abrogated if necessary. METHODS: We analyzed the effect of chlorpromazine, an inhibitor of clathrin-dependent endocytosis and apigenin, a cell cycle regulator, on adenovirus replication and toxicity. First, we evaluated the in vitro replication of a tumor targeted Rb-p16 pathway selective oncolytic adenovirus (Ad5/3-Delta24) and a wild-type adenovirus in normal cells, fresh liver samples and in ovarian cancer cell lines. Further, we analyzed the in vitro cell killing efficacy of adenoviruses in the presence and absence of the substances. Moreover, the effect on in vivo efficacy, replication and liver toxicity of the adenoviruses was evaluated. RESULTS: We demonstrate in vitro and in vivo reduction of adenovirus replication and associated toxicity with chlorpromazine and apigenin. Effective doses were well within what would be predicted safe in humans. CONCLUSIONS: Chlorpromazine and apigenin might reduce the replication of adenovirus, which could provide a safety switch in case replication-associated side effects are encountered in patients. In addition, these substances could be useful for the treatment of systemic adenoviral infections in immunosuppressed patients. 相似文献
999.
Pazos Mde C Ricci R Simioni AR Lopes CC Tedesco AC Nader HB 《The international journal of biochemistry & cell biology》2007,39(6):1130-1141
INTRODUCTION: Photodynamic therapy is based on the selective retention of a photosensitizer by highly proliferating cells and its activation with light at the appropriate wavelength. This combination generates reactive oxygen species that ultimately kill the cells. Some cells, however, may survive photodynamic therapy and the interaction of these cells with the extracellular matrix has profound effect in tumor biology. The knowledge of photodynamic therapy action on the extracellular matrix has not been fully explored. It has been focused mainly on integrins, matrix metalloproteinases and on growth factors and immunological mediators. Other important molecules involved in the regulation of many cell processes are the glycosaminoglycans, polymers of disaccharide units, present on the cell surface and in the extracellular matrix. In most cases, the glycosaminoglycans occur as proteoglycans. AIMS: The purpose of the present investigation is to evaluate heparan sulfate proteoglycan expression and shedding, and its relation to the survival of the remaining cells, after a liposomal-AlClPc based photodynamic treatment. MATERIALS: A wild-type endothelial cell derived from rabbit aorta and its counterpart transfected with EJ-ras oncogene were used. RESULTS: Both cell lines presented augmented heparan sulfate proteoglycan syndecan-4 mRNA expression, augmented synthesis of heparan sulfate chains and increased shedding. Also, the formation of stress fibers on the border of the cells and the arrest in G(1) phase of the cell cycle was observed. CONCLUSIONS: These results show that surviving cells after photodynamic therapy exhibit changes in their morphology and cell processes that differ from that of non-treated cells, and these changes are probably hindering the cells from resuming normal proliferation. 相似文献
1000.
Jacq L Garnier S Dieudé P Michou L Pierlot C Migliorini P Balsa A Westhovens R Barrera P Alves H Vaz C Fernandes M Pascual-Salcedo D Bombardieri S Dequeker J Radstake TR Van Riel P van de Putte L Lopes-Vaz A Glikmans E Barbet S Lasbleiz S Lemaire I Quillet P Hilliquin P Teixeira VH Petit-Teixeira E Mbarek H Prum B Bardin T Cornélis F;European Consortium on Rheumatoid Arthritis Families 《Arthritis research & therapy》2007,9(4):R63-7
The integrin alpha(v)beta3, whose alpha(v) subunit is encoded by the ITGAV gene, plays a key role in angiogenesis. Hyperangiogenesis is involved in rheumatoid arthritis (RA) and the ITGAV gene is located in 2q31, one of the suggested RA susceptibility loci. Our aim was to test the ITGAV gene for association and linkage to RA in a family-based study from the European Caucasian population. Two single nucleotide polymorphisms were genotyped by PCR-restriction fragment length polymorphism in 100 French Caucasian RA trio families (one RA patient and both parents), 100 other French families and 265 European families available for replication. The genetic analyses for association and linkage were performed using the comparison of allelic frequencies (affected family-based controls), the transmission disequilibrium test, and the genotype relative risk.We observed a significant RA association for the C allele of rs3738919 in the first sample (affected family-based controls, RA index cases 66.5% versus controls 56.7%; P = 0.04). The second sample showed the same trend, and the third sample again showed a significant RA association. When all sets were combined, the association was confirmed (affected family-based controls, RA index cases 64.6% versus controls 58.1%; P = 0.005). The rs3738919-C allele was also linked to RA (transmission disequilibrium test, 56.5% versus 50% of transmission; P = 0.009) and the C-allele-containing genotype was more frequent in RA index cases than in controls (RA index cases 372 versus controls 339; P = 0.002, odds ratio = 1.94, 95% confidence interval = 1.3-2.9). The rs3738919-C allele of the ITGAV gene is associated with RA in the European Caucasian population, suggesting ITGAV as a new minor RA susceptibility gene. 相似文献