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Objectives of this study were to develop a technique for quantifying cardiac-specific norepinephrine (NE) mass transport and determine whether cardiac NE kinetic modeling parameters were related to physiological variables of left ventricular (LV) size and systolic performance in nine patients with chronic mitral regurgitation. Biplane contrast cineventriculograms were used to determine LV size and ejection fraction (EF), micromanometer LV pressures and radionuclide LV volumes from a range of loading conditions to calculate LV end-systolic elastance, and [(3)H]NE infusions with LV and coronary sinus sampling for [(3)H]NE and endogenous NE during and after termination of infusions to model NE mass transport. Total NE release rate into cardiac interstitial fluid (M(IF)(R)) averaged 859 +/- 214 and NE released de novo into cardiac interstitial fluid (M(IF)(u,r,en)) averaged 546 +/- 174 pmol/min. Both M(IF)(R) and M(IF)(u,r,en)correlated directly with LV end-systolic volume (r = 0.84, P = 0.005; r = 0.86, P = 0.003); inversely with LV EFs (r = -0.75, P = 0.02; r = -0.81, P = 0.008); and inversely with LV end-systolic elastance values, optimally fit by a nonlinear function (r = 0.89, P = 0.04; r = 0.96, P = 0.01). We conclude that total and newly released NE into interstitial fluid of the heart, determined by regional mass transport kinetic model, are specific measures of regional cardiac-specific sympathetic nervous system activity and are strongly related to measures of LV size and systolic performance. These data support the concept that this new model of organ-specific NE kinetics has physiological relevance.  相似文献   
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We compared the kinetics of activation and antimicrobial activities of MAPK-p38 and MAPK-ERK in bovine monocytes infected with Mycobacterium avium subsp. paratuberculosis (MAP) and Mycobacterium avium subsp. avium (Maa). Monocytes were incubated with MAP or Maa organisms with or without a specific inhibitor of the MAPK-p38 pathway (SB203580), and MAPK phosphorylation and antimicrobial functions of monocytes were evaluated. At early time points MAPK-p38 phosphorylation was greater in MAP-infected bovine monocytes than in Maa-infected monocytes. At later time points MAPK-p38 phosphorylation by both organisms was similar. MAPKp38 phosphorylation in MAP-infected monocytes was similar to negative control cells, whereas in Maa-infected this activation remained greater than negative control cells. Increase phosphorylation MAPK-ERK was similar at all time points for both organisms. Bovine monocytes had minimal capacity to kill MAP organisms, to acidify MAP-containing phagosomes, or to form phagolysosome. Alternatively, bovine monocytes were able to kill Maa organisms. Addition of SB203580 to monocyte cultures increased phagosome acidification, phagolysosome formation, and killing of MAP and Maa organisms. Taken together these data indicate that early transient activation of MAPK-p38 in bovine mononuclear phagocytes by MAP organisms may be a key mechanism involved in the capacity of MAP to survive in bovine monocytes.  相似文献   
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A new method for the determination of Cu(II) and Pb(II) by flame atomic absorption spectrometry (FAAS) after preconcentrating on a column containing Anoxybacillus sp. SO B1–immobilized Amberlite XAD-16 was developed. The functional groups of Anoxybacillus sp. SO B1 immobilized on Amberlite XAD-16 were characterized in KBr tablets by Fourier transform infrared (FT-IR) spectrometry. Various parameters such as pH, amount of the adsorbent, eluent type and volume, and flow rate of the sample solution were studied. The optimum pH values of quantitative sorption for Cu(II) and Pb(II) were found to be pH 7.0 and 5.0 and Cu(II) and Pb(II) ions could be quantitatively eluted with 5.0 ml of 1.0 mol L?1 HCI and 10.0 ml of 0.25 mol L?1 HNO3, respectively. Recoveries of Cu(II) and Pb(II) were found to be 100.9 ± 1.57% and 100.3 ± 0.49% (N = 5), the limits of detection of Cu(II) and Pb(II) in the determination by FAAS (3 s, N = 10) were found to be 0.8 and 1.6 μg L?1, respectively. The proposed enrichment method was applied for metal ion determination from water samples such as two parts of Tigris River water in Diyarbak?r and Elaz??, Lake of Hazar in Elaz??, and tap water in Diyarbak?r. Furthermore, the accuracy of the proposed method was verified by studying the analytical recovery and by analyzing certified reference material (NCS-DC 73350 leaves of poplar).  相似文献   
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Several genes encoding for different cytokines may play crucial roles in host susceptibility to tuberculosis (TB), since the cytokine production capacity varies among individuals and depends on the cytokine gene polymorphism. The association of the cytokine gene polymorphisms with the development of TB was investigated in this study. DNA samples were obtained from a Turkish population of 81 patients with the different clinical forms of TB, and 50 healthy control subjects. All genotyping (IL-6, IL-10, IFN-gamma, TGF-beta and TNF-alpha) experiments were performed using sequence-specific primers PCR (PCR-SSP). Analysis of allele frequencies showed that IL-10 -1082 G allele frequency was significantly more common in TB patients than healthy controls (37.7% vs 23.0%, p: 0.014). No statistically significant differences were observed between the different clinical forms of the disease. These results suggest that the polymorphisms in IL-10 gene may affect susceptibility to TB and increase risk of developing the disease. To confirm the biological significance of our results, further studies should be performed on other population groups.  相似文献   
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This study evaluated different concentrations of selective serotonin-reuptake inhibitors (citalopram and sertraline) for genotoxicity by use of the somatic mutation and recombination test (SMART) in Drosophila melanogaster. Three-day-old larvae, trans-heterozygous for the multiple wing hairs (mwh) and flare (flr3) genes were treated with these two compounds. Two recessive markers were located on the left arm of chromosome 3, i.e. 'multiple wing hairs' (mwh) in map position 0.3 and 'flare-3' (flr3) at 38.8, while the centromere was located in position 47.7. SMART is based on the loss of heterozygosity, which may occur through various mechanisms, such as mitotic recombination, mutation, deletion, half-translocation, chromosome loss, and non-disjunction. Genetic changes occurring in somatic cells of the wing's imaginal discs, cause the formation of mutant clones on the wing blade. The results of this study show that citalopram had a genotoxic effect in the Drosophila SMART. Sertraline, however, did not show any genotoxic effect in balancer heterozygous wings. This study concluded that more information is needed to be certain regarding the mutagenic effects of sertraline.  相似文献   
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Although our knowledge about Brucella virulence factors and the host response increase rapidly, the mechanisms of immune evasion by the pathogen and causes of chronic disease are still unknown. Here, we aimed to investigate the immunological factors which belong to CD8+ T cells and their roles in the transition of brucellosis from acute to chronic infection. Using miRNA microarray, more than 2000 miRNAs were screened in CD8+ T cells of patients with acute or chronic brucellosis and healthy controls that were sorted from peripheral blood with flow cytometry and validated through qRT-PCR. Findings were evaluated using GeneSpring GX (Agilent) 13.0 software and KEGG pathway analysis. Expression of two miRNAs were determined to display a significant fold change in chronic group when compared with acute or control groups. Both miRNAs (miR-126-5p and miR-4753-3p) were decreased (p <0.05 or fold change > 2). These miRNAs have the potential to be the regulators of CD8+ T cell-related marker genes for chronic brucellosis infections. The differentially expressed miRNAs and their predicted target genes are involved in MAPK signaling pathway, cytokine-cytokine receptor interactions, endocytosis, regulation of actin cytoskeleton, and focal adhesion indicating their potential roles in chronic brucellosis and its progression. It is the first study of miRNA expression analysis of human CD8+ T cells to clarify the mechanism of inveteracy in brucellosis.  相似文献   
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