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101.
The current study was conducted on a sample of 91 patients diagnosed with diastolic dysfunction (DD) with preserved systolic function caused by a painful chronic ischaemic cardiopathy – angina pectoris stable at the effort. The diagnosis was established following anamnesis, electrocardiogram, and echocardiography. Myeloperoxidase (MPO) serum levels were assessed in all patients and then these values were correlated with some of the echocardiography parameters that proved the mentioned diagnosis.

In conclusion, the execution of this investigation triad (electrocardiogram, echocardiography, and MPO) allows:

  • Stratifying the patients depending on the disease risk by early detecting of any possible DD with preserved systolic function.

  • The use of the MPO increased circulating levels as a biomarker for diagnosis and risk due to the statistically significant correlation between those and the results of the other two aforementioned paraclinical investigation.

  相似文献   
102.
Allelopathy, here defined as biochemical interactions between aquatic primary producers, has always been intriguing as a process explaining the dominance of certain plant or algal species over others. Negative chemical interference has been invoked as one of the steering mechanisms behind mutual dominance of either submerged macrophytes or phytoplankton in shallow eutrophic lakes. Yet, despite much effort, convincing evidence for allelopathic interactions in situ is still missing. Also, laboratory approaches often lack reality. Inspired by a series of talks at the Shallow Lakes 2005 meeting in Dalfsen, the Netherlands, we argue that there is circumstantial but strong evidence that allelopathic interference between submerged macrophytes and phytoplankton may indeed exist in aquatic ecosystems despite the problems associated with research in this field. We first discuss experimental approaches combining laboratory and field studies, based on examples presented at this meeting. We then discuss the impact of nutrient status of both producing and target organism and biotic factors such as herbivory or pathogens that might affect allelopathy. Further topics are the potential seasonality of effects and the species-specificity of certain allelochemicals. We conclude with some thoughts why a final proof for allelopathy in situ might remain difficult or even inaccessible in some cases, and why we nevertheless should not abandon this idea.  相似文献   
103.
The cell lineage tree of a multicellular organism represents its history of cell divisions from the very first cell, the zygote. A new method for high-resolution reconstruction of parts of such cell lineage trees was recently developed based on phylogenetic analysis of somatic mutations accumulated during normal development of an organism. In this study we apply this method in mice to reconstruct the lineage trees of distinct cell types. We address for the first time basic questions in developmental biology of higher organisms, namely what is the correlation between the lineage relation among cells and their (1) function, (2) physical proximity and (3) anatomical proximity. We analyzed B-cells, kidney-, mesenchymal- and hematopoietic-stem cells, as well as satellite cells, which are adult skeletal muscle stem cells isolated from their niche on the muscle fibers (myofibers) from various skeletal muscles. Our results demonstrate that all analyzed cell types are intermingled in the lineage tree, indicating that none of these cell types are single exclusive clones. We also show a significant correlation between the physical proximity of satellite cells within muscles and their lineage. Furthermore, we show that satellite cells obtained from a single myofiber are significantly clustered in the lineage tree, reflecting their common developmental origin. Lineage analysis based on somatic mutations enables performing high resolution reconstruction of lineage trees in mice and humans, which can provide fundamental insights to many aspects of their development and tissue maintenance.  相似文献   
104.
Some new dimethoxyethane (DME) adducts of lanthanide trichlorides of formula [LnCl3(DME)2]n, n=1 or 2; (n=2, Ln=La, Ce, Pr, Nd; n=1, Ln=Eu, Tb, Ho, Tm, Lu) have been prepared by treating Ln2O3, or LnCl3 · nH2O, or Ln2(CO3)3, in DME as medium, with thionyl chloride at room temperature, eventually in the presence of water in the case of Ln2O3 and Ln2(CO3)3. The complexes from lanthanum to praseodymium included are chloro-bridged dimers. In the case of neodymium, the new results complement the literature data, showing that both the mononuclear and dinuclear species exist: neodymium can therefore be regarded as the turning element from dinuclear to mononuclear structures along the series. Only mononuclear complexes were isolated in the Eu-Lu sequence. The lanthanide contraction has been evaluated on the basis of the Ln-O and Ln-Cl bond distances on the isotypical series of the mononuclear complexes LnCl3(DME)2 covering a range of 12 atomic numbers.  相似文献   
105.
Primary cells, such as HUVEC, are notoriously difficult to transfect and are susceptible to the toxic effects of transfection reagents. A transfection reagent with a high transfection efficiency and low cytotoxicity was sought to retain sufficient viability of transfected HUVEC for subsequent assays. Nine chemical transfection reagents, currently commercially available, were compared for their ability to transfect HUVEC in vitro. A plasmid expressing the enhanced GFP (EGFP) was used for transfection, followed by flow cytometry of transfected HUVEC to determine the proportion of EGFP-expressing cells as a measure of transfection efficiency. Lipofectamine 2000 and Lipofectamine LTX (Invitrogen, Carlsbad, CA, USA) gave the highest transfection efficiencies of the reagents tested. Lipofectamine LTX was identified as the optimal transfection reagent as a result of its higher transfection efficiency at shorter periods of time following transfection when cytotoxicity was limited, allowing sufficient yield of transfected HUVEC for use in subsequent assays.  相似文献   
106.
Understanding the mechanisms by which marine organisms cope to environmental stressful conditions is a fundamental question for ecotoxicology. We examined biochemical and cellular responses of Hypnea musciformis exposed in vitro to four concentrations of diesel oil (0 (control), 0.001, 0.01, 0.1, and 1 % v/v) for 0, 30 min, 1, 12, and 24 h. Chl a content decreased after exposure for 1, 12, and 24 h. Carotenoids increased after 30 min and 12 h and decreased after 1 and 24 h. Phenolic content was lower in samples exposed to 0.1 and 1 % of diesel oil. After treatment, samples showed a decrease in floridean starch grains, cell volume and autofluorescence intensity, changes in chloroplast morphology, and on the surface topography of the cell wall. These findings provide preliminary but important results on biochemical and cellular responses of H. musciformis when exposed to diesel oil and could be considered as tools for monitoring oil spills.  相似文献   
107.
108.
The expression of adrenomedullin (AM) and atrial natriuretic factor (ANF) were investigated in the myocardium of a rat model of chronic ischemic heart failure (CHF) compared with sham-operated controls. In addition, human myocardium of patients with end-stage heart failure due to idiopathic dilated cardiomyopathy compared with myocardium of normal subjects (NF) was studied. In CHF, similar AM levels but increased ANF expression were observed in left ventricular myocardium, as assessed by semiquantitative PCR. Functional experiments with freshly excised papillary muscles showed no influence of AM on myocardial contractility. In NF human myocardium, the expression of AM mRNA was threefold higher in atrial compared with ventricular tissue. In analogy, ANF mRNA was increased by approximately 15-fold in atrial tissue. In dilated cardiomyopathy, the expression of AM was significantly increased in right and left ventricles compared with NF. In parallel, ventricular ANF expression was enhanced.  相似文献   
109.
Introduction: Metabolic syndrome (MetS) and high-sensitivity cardiac troponin T (hs-TnT) are associated with higher risk for cardiovascular diseases (CVD). Our aim was to assess the relation between hs-TnT elevation and MetS in a general population sample.

Materials and methods: Individuals participating in an annual health survey program between 2010 and 2016 were included in the study. Blood samples including hs-TnT levels were collected. The study population was divided into three groups based on hs-TnT levels – undetectable (<5?ng/L), intermediate (5–14?ng/L) and elevated (>14?ng/L).

Results: A total of 5994 subjects were included in the study, the mean age was 48.5 and 4336 (72%) were males. Compared with subjects with undetectable hs-TnT the prevalence of MetS was higher in those with detectable and elevated levels – 392 (10%) vs. 270 (15%) and 51 (33%), respectively (p?<?0.001). In a multivariate model adjusted for age, gender and multiple co-morbidities, the number of MetS components and presence of MetS were significantly associated with an increased risk for detectable hs-TnT levels (OR?=?1.02 {for each component}; 95% CI [1.00–1.05], p?=?0.04) and (OR?=?1.13; 95% CI [1.07–1.2], p?<?0.001) respectively. Only the waist, glucose and hypertension components of the MetS were significantly associated with elevated troponin.

Conclusions: The MetS and its distinct components have a cumulative impact on hs-TnT levels in apparently healthy subjects.  相似文献   

110.
The aim of this work was to identify which aspects of photosynthetic metabolism respond most sensitively to leaf water deficit. Spinach (Spinacia oleracea L.) leaf discs were floated on sorbitol concentrations of increasing molarity and changes of the protoplast volume were estimated using [14C]sorbitol and 3H2O penetration. Detached leaves were also wilted until 10% of their fresh weight was lost. Photosynthesis was studied at very high external CO2 concentrations, to eliminate the effect of closing stomata. There was no large inhibition of CO2 fixation after wilting leaves, or until the external water deficit was greater than-1.2 MPa. However, partitioning changed markedly at these moderate water deficits: more sucrose and less starch was made. When an inhibition of CO2-saturated photosynthesis did appear at a water deficit of-2.0 MPa and above, measurements of chlorophyll-fluorescence quenching and metabolite levels showed the thylakoid reactions were not especially susceptible to short-term water stress. The inhibition was accompanied by a small increase of the triose phosphate: ribulose-1,5-bisphosphate ratio, showing regeneration of ribulose-1,5-bisphosphate was affected. However, there was also a general increase of the estimated concentrations of most metabolites, indicating that there is no specific site for the inhibition of photosynthesis. Increasing water deficit led to a large increase of fructose-2,6-bisphosphate. This is explained in terms of a simultaneous increase of fructose-6-phosphate and inorganic phosphate as the cell shrinks. The high fructose-2,6-bisphosphate led to the accumulation of triose phosphates, and the potential significance of this for protection against photoinhibition is discussed. There was an increase in the extractable activity of sucrose-phosphate synthase. This was only detected when the enzyme was assayed in conditions which distinguish between different kinetic forms which have previously been identified in spinach leaves. It is proposed that activation of sucrose-phosphate synthase is one of the first sites at which spinach leaves respond to a rising water deficit. This could be of importance for osmoregulation.Abbreviations Chl chlorophyll - Fru1,6bisP fructose-1,6-bisphosphate - Fru2,6bisP fructose-2,6-bisphosphate - Fru6P fructose-6-phosphate - Glc6P glucose-6-phosphate - PGA glycerate-3-phosphate - Pi inorgamic phosphate - Ru1,5bisP ribulose-1,5-bisphosphate - SPS sucrose-phosphate synthase - triose-P sum of glyceraldehyde-3-phosphate and dehydroxyacetone phosphate - UDPGlc uridine diphosphoglucose  相似文献   
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