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1.
Biochemical, histological and electron-microscopic examinations of the heart and the aorta of albino rats exposed to carbon disulphide in concentrations of 10, 50, 100 and 200 mg . m-3 were carried out. Changes in the metabolic and energetic processes in the myocardium and in the quantitative and qualitative characteristics of the connective tissue of the aortal vessel wall were observed. The established disorders follow the dose-effect dependence. The authors studied the effect of carbon disulphide in concentrations of 10 and 50 mg . m-3 on the electrophoretic spectrum of serum proteins, the quantitative and qualitative characteristics of fibrous structures in the myocardium and the aorta of albino rats fed on atherogenic diet (cholesterol, cholic acid and vitamin D2). The combination of carbon disulphide with the atherogenic factor leads to intensification of changes in the cardiovascular system and in serum proteins, observed after independent exposure to either of the factors. The combination of atherogenic diet and 10 mg . m-3 carbon disulphide induced symptoms of intoxication, decreased survival of the animals, and the developing sclerotic process was found to be more severe and to progress more rapidly than in animals subject to atherogenic diet alone. The obtained results testify to cardiovascular effect of carbon disulphide. The observed atherogenic effect of carbon disulphide in low concentrations is most probably connected with its direct effect on the myocardium and the vessels.  相似文献   
2.
The denaturation of short (145 base pairs) and long (about 8000 base pairs) DNA moelucules has been studied by adiabitic differential microcalorimetry in solutions with different NaCl content. It is found that the enthalpy of denaturation of short DNA is more sensitive to changes in Tm than that of long DNA. A comparison with other data is also given.  相似文献   
3.
The optimal conditions for the application of M13 DNA fingerprinting to the genus Lactobacillus were determined. Comparative fingerprint analysis of representative strains of Lactobacillus delbrueckii subsp. delbrueckii, Lact. delbrueckii subsp. lactis, Lact. delbrueckii subsp. bulgaricus, Lact. helveticus and Lact. casei permitted the differentiation of species, subspecies and individual strains and the quantitative determination of their genetic relatedness. The results confirm the high specificity of M13 DNA fingerprinting and indicate that it might be used in the classification of Lactobacillus spp.  相似文献   
4.
5.
Water-soluble Maillard reaction products obtained from five different model systems were investigated for their effects upon the mechanical activity of rat gastric smooth muscle. Most of the total Maillard reaction products applied at concentration of 1.5 mg/ml evoked contractions; among them the product obtained from arginine and glucose (Arg-Glc) produced the most powerful contractions. The product obtained from glycine and ascorbic acid (Gly-AsA) was the only one that brought about relaxation response. The high molecular weight fractions (>3,500 Da) isolated from the reaction systems Arg-Glc and Gly-AsA demonstrated effects similar in type and amplitude to those evoked by non-fractioned reaction products. The results obtained suggest that moieties of molecules acting upon the muscle tonus originate mainly from lysine and arginine residues; that these structures are available in both low and high molecular pools in similar concentrations, and most likely these fragments act upon membrane-located cellular structures involved in calcium transport.  相似文献   
6.
Coumarin and its derivatives are naturally occurring substances with multiple biological activities. Here we demonstrate that prophylactic peroral administration of coumarin or 7-hydroxycoumarin (7-OHC) enhances resistance to subsequent lethal Salmonella enterica Serovar Typhimurium infection in mice. 7-OHC decreased bacterial load in liver and spleen, and enhanced phagocytosis and bacterial killing by macrophages when applied in vitro and in vivo. 7-OHC treatment induced significant NO release in peritoneal macrophage cultures. The observed protective effect correlated with the induction of Th1-associated cytokines, such as IL-12, IFN-gamma, and TNF-alpha. These data demonstrate a clear immunomodulatory potential of coumarins which might have important therapeutic implications to enhance resistance to infection.  相似文献   
7.
Sepsis is a major cause for death worldwide. Numerous interventional trials with agents neutralizing single proinflammatory mediators have failed to improve survival in sepsis and aseptic systemic inflammatory response syndromes. This failure could be explained by the widespread gene expression dysregulation known as “genomic storm” in these patients. A multifunctional polyspecific therapeutic agent might be needed to thwart the effects of this storm. Licensed pooled intravenous immunoglobulin preparations seemed to be a promising candidate, but they have also failed in their present form to prevent sepsis-related death. We report here the protective effect of a single dose of intravenous immunoglobulin preparations with additionally enhanced polyspecificity in three models of sepsis and aseptic systemic inflammation. The modification of the pooled immunoglobulin G molecules by exposure to ferrous ions resulted in their newly acquired ability to bind some proinflammatory molecules, complement components and endogenous “danger” signals. The improved survival in endotoxemia was associated with serum levels of proinflammatory cytokines, diminished complement consumption and normalization of the coagulation time. We suggest that intravenous immunoglobulin preparations with additionally enhanced polyspecificity have a clinical potential in sepsis and related systemic inflammatory syndromes.  相似文献   
8.
The response of wheat to the variables of climate change includes elevated CO2, high temperature, and drought which vary according to the levels of each variable and genotype. Independently, elevated CO2, high temperature, and terminal drought affect wheat biomass and grain yield, but the interactive effects of these three variables are not well known. The aim of this study was to determine the effects of elevated CO2 when combined with high temperature and terminal drought on the high‐yielding traits of restricted‐tillering and vigorous growth. It was hypothesized that elevated CO2 alone, rather than combined with high temperature, ameliorates the effects of terminal drought on wheat biomass and grain yield. It was also hypothesized that wheat genotypes with more sink capacity (e.g. high‐tillering capacity and leaf area) have more grain yield under combined elevated CO2, high temperature, and terminal drought. Two pairs of sister lines with contrasting tillering and vigorous growth were grown in poly‐tunnels in a four‐factor completely randomized split‐plot design with elevated CO2 (700 µL L?1), high day time temperature (3 °C above ambient), and drought (induced from anthesis) in all combinations to test whether elevated CO2 ameliorates the effects of high temperature and terminal drought on biomass accumulation and grain yield. For biomass and grain yield, only main effects for climate change variables were significant. Elevated CO2 significantly increased grain yield by 24–35% in all four lines and terminal drought significantly reduced grain yield by 16–17% in all four lines, while high temperature (3 °C above the ambient) had no significant effect. A trade‐off between yield components limited grain yield in lines with greater sink capacity (free‐tillering lines). This response suggests that any positive response to predicted changes in climate will not overcome the limitations imposed by the trade‐off in yield components.  相似文献   
9.
Legumes, as protein-rich crops, are widely used for human food, animal feed and vegetable oil production. Over the past decade, two legume species, Medicago truncatula and Lotus japonicus, have been adopted as model legumes for genomics and physiological studies. The tobacco transposable element, Tnt1, is a powerful tool for insertional mutagenesis and gene inactivation in plants. A large collection of Tnt1-tagged lines of M. truncatula cv. Jemalong was generated during the course of the project 'GLIP': Grain Legumes Integrated Project, funded by the European Union (www.eugrainlegumes.org). In the project 'IFCOSMO': Integrated Functional and COmparative genomics Studies on the MOdel Legumes Medicago truncatula and Lotus japonicus, supported by a grant from the Ministry of Education, Youth and Science, Bulgaria, these lines are used for development of functional genomics platform of legumes in Bulgaria. This review presents recent advances in the evaluation of the M. truncatula Tnt1 mutant collection and outlines the steps that are taken in using the Tnt1-tagging for generation of a mutant collection of the second model legume L. japonicus. Both collections will provide a number of legume-specific mutants and serve as a resource for functional and comparative genomics research on legumes. Genomics technologies are expected to advance genetics and breeding of important legume crops (pea, faba bean, alfalfa and clover) in Bulgaria and worldwide.  相似文献   
10.

Background

Mesenchymal stem cells (MSC) are currently strong candidates for cell-based therapies. They are well known for their differentiation potential and immunoregulatory properties and have been proven to be potentially effective in the treatment of a large variety of diseases, including neurodegenerative disorders. Currently there is no treatment that provides consistent long-term benefits for patients with multiple system atrophy (MSA), a fatal late onset α-synucleinopathy. Principally neuroprotective or regenerative strategies, including cell-based therapies, represent a powerful approach for treating MSA. In this study we investigated the efficacy of intravenously applied MSCs in terms of behavioural improvement, neuroprotection and modulation of neuroinflammation in the (PLP)-αsynuclein (αSYN) MSA model.

Methodology/Principal Findings

MSCs were intravenously applied in aged (PLP)-αSYN transgenic mice. Behavioural analyses, defining fine motor coordination and balance capabilities as well as stride length analysis, were performed to measure behavioural outcome. Neuroprotection was assessed by quantifying TH neurons in the substantia nigra pars compacta (SNc). MSC treatment on neuroinflammation was analysed by cytokine measurements (IL-1α, IL-2, IL-4, IL-5, IL-6, IL-10, IL-17, GM-CSF, INFγ, MCP-1, TGF-β1, TNF-α) in brain lysates together with immunohistochemistry for T-cells and microglia.Four weeks post MSC treatment we observed neuroprotection in the SNc, as well as downregulation of cytokines involved in neuroinflammation. However, there was no behavioural improvement after MSC application.

Conclusions/Significance

To our knowledge this is the first experimental approach of MSC treatment in a transgenic MSA mouse model. Our data suggest that intravenously infused MSCs have a potent effect on immunomodulation and neuroprotection. Our data warrant further studies to elucidate the efficacy of systemically administered MSCs in transgenic MSA models.  相似文献   
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