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41.
Objectives: acute coronary syndrome (ACS) is defined as an inflammatory disease associated with development of atherosclerosis and instability. IL-1 is a candidate inflammatory cytokine that is thought to trigger ACS. The purpose of this study was to determine the relationship between IL-1 gene family polymorphisms (IL-1RN, IL-1B in positions -511 and +3953) and ACS in the Turkish population. Methods: a total of 381 people participated in the study, with 117 control subjects and 264 ACS patients. Of the 264 ACS patients, 112 were diagnosed with stable angina pectoris (SAP) and 152 were diagnosed with unstable angina pectoris (USAP). The polymerase chain reaction (PCR) was used to determine the genotype of IL-1RN. The genotypes of IL-1B (-511 and +3953) were determined by PCR, followed by restriction enzyme digestion of the PCR products. Results: there were no significant differences in both IL-1RN, IL-1B (-511 and +3953) genotype distributions and IL-1RN allele frequencies between ACS patients and the control subjects. In addition, no association was observed in the allele frequency of IL-1B (-511 and +3953) between ACS patients and controls (p = 0.113 and p = 0.859, respectively), or between SAP patients and controls (p = 0.575 and p = 0.359, respectively). However, IL-1B allele 1 (C) (-511) polymorphism in USAP patients was found to be significantly different from that of control subjects (p = 0.041, OR: 2.01; 95% CI: 1.985-3.933). A significant difference was also observed between USAP and SAP patients for IL-1B (+3953) allele 1 (C) polymorphism; (p = 0.043, OR: 1.522; 95% CI: 1.012-2.88). Conclusion: these results show that IL-1RN gene polymorphism has no association with ACS. However, the allele 1 (C) of IL-1B (-511) may be a risk factor for susceptibility to USAP in the Turkish population. 相似文献
42.
Interactions of inertial cavitation bubbles with stratum corneum lipid bilayers during low-frequency sonophoresis 下载免费PDF全文
Interactions of acoustic cavitation bubbles with biological tissues play an important role in biomedical applications of ultrasound. Acoustic cavitation plays a particularly important role in enhancing transdermal transport of macromolecules, thereby offering a noninvasive mode of drug delivery (sonophoresis). Ultrasound-enhanced transdermal transport is mediated by inertial cavitation, where collapses of cavitation bubbles microscopically disrupt the lipid bilayers of the stratum corneum. In this study, we describe a theoretical analysis of the interactions of cavitation bubbles with the stratum corneum lipid bilayers. Three modes of bubble-stratum corneum interactions including shock wave emission, microjet penetration into the stratum corneum, and impact of microjet on the stratum corneum are considered. By relating the mechanical effects of these events on the stratum corneum structure, the relationship between the number of cavitation events and collapse pressures with experimentally measured increase in skin permeability was established. Theoretical predictions were compared to experimentally measured parameters of cavitation events. 相似文献
43.
C1D is a gamma-irradiation inducible nuclear matrix protein that interacts with and activates the DNA-dependent protein kinase (DNA-PK) that is essential for the repair of the DNA double-strand breaks and V(D)J recombination. Recently, it was demonstrated that C1D can also interact with TRAX and prevent the association of TRAX with Translin, a factor known to bind DNA break-point junctions, and that over expression of C1D can induce p53-dependent apoptosis. Taken together, these findings suggest that mammalian C1D could be involved in maintenance of genome integrity by regulating the activity of proteins involved in DNA repair and recombination. To obtain direct evidence for the biological function of C1D that we show is highly conserved between diverse species, we have analysed the Saccharomyces cerevisiae C1D homologue. We report that the disruption of the YC1D gene results in a temperature sensitivity and that yc1d mutant strains exhibit defects in non-homologous DNA end joining (NHEJ) and accurate DNA repair. In addition, using a novel plasmid-based in vivo recombination assay, we show that yc1d mutant strains are also defective in homologous recombination. These results indicate that YC1D is implicated in both homologous recombination and NHEJ pathways for the repair of DNA double-strand breaks. 相似文献
44.
Fas ligand (CD95 ligand) controls angiogenesis beneath the retina 总被引:15,自引:0,他引:15
A principal cause of blindness is subretinal neovascularization associated with age-related macular degeneration. Excised neovascular membranes from patients with age-related macular degeneration demonstrated a pattern of Fas+ new vessels in the center of the vascular complex, surrounded by FasL+ retinal pigment epithelial cells. In a murine model, Fas (CD95)-deficient (Ipr) and FasL-defective (gld) mice had a significantly increased incidence of neovascularization compared with normal mice. Furthermore, in gld mice there is massive subretinal neovascularization with uncontrolled growth of vessels. We found that cultured choroidal endothelial cells were induced to undergo apoptosis by retinal pigment epithelial cells through a Fas-FasL interaction. In addition, antibody against Fas prevented vascular tube formation of choroidal endothelial cells derived from the eye in a three-dimensional in vitro assay. Thus, FasL expressed on retinal pigment epithelial cells may control the growth and development of new subretinal vessels that can damage vision. 相似文献
45.
Iodine and zinc, but not selenium and copper, deficiency exists in a male Turkish population with endemic goiter 总被引:1,自引:0,他引:1
Metin Ozata Murat Salk Ahmet Aydin Savas Sayin Cagatay Oktenli Zeynel Beyham Askin Isimer I. Caglayan Ozdemir 《Biological trace element research》1999,69(3):211-216
Although endemic goiter has been shown to have a high prevalence in Turkey, little is known about the concentration of urinary
iodine, plasma selenium (Se), copper (Cu), and zinc (Zn) in these patients. We studied on 140 male patient with endemic goiter
(mean age: 22.2 ± 0.19 yr) and 140 healthy male subjects (mean age: 21.8 ± 0.28 yr). Daily urinary iodine excretion was determined
by the ionometric method. Plasma Se, Zn, and Cu were determined by using atomic absorption spectrometry. Daily urinary iodine
excretion was found to be significantly lower in the patient group (38.7 ± 2.26 μg/d) than that of controls (50.73 ± 2.56
μg/day,p = 0.001). Plasma Zn concentrations were also found to be significantly lower in the patient group (1.04 ± 0.03 μg/mL) than
that of controls (1.16 ± 0.02 μg/mL,p = 0.001). No significant difference was determined in Se and Cu concentrations between the patient and control groups. Our
study shows that a moderate iodine deficiency exists in both patients with endemic goiter and control subjects, which indicates
the important role of iodine deficiency in the etiopathogenesis of endemic goiter in Turkey. Zinc deficiency may also contribute
to the pathogenesis of endemic goiter. However, Se and Cu do not seem to have any role in the etiopathogenesis of endemic
goiter in Turkey. A community-based iodine fortification program throughout the country may be proposed to take over the problem,
which also can prevent the contributing effects of other element deficiencies that occur when iodine deficiency is the prevailing
factor. 相似文献
46.
Background
Cell cooperation is a critical event during tissue development. We present the first precise metrics to quantify the interaction between mesenchymal stem cells (MSCs) and extra cellular matrix (ECM). In particular, we describe cooperative collagen alignment process with respect to the spatio-temporal organization and function of mesenchymal stem cells in three dimensions.Methodology/Principal Findings
We defined two precise metrics: Collagen Alignment Index and Cell Dissatisfaction Level, for quantitatively tracking type I collagen and fibrillogenesis remodeling by mesenchymal stem cells over time. Computation of these metrics was based on graph theory and vector calculus. The cells and their three dimensional type I collagen microenvironment were modeled by three dimensional cell-graphs and collagen fiber organization was calculated from gradient vectors. With the enhancement of mesenchymal stem cell differentiation, acceleration through different phases was quantitatively demonstrated. The phases were clustered in a statistically significant manner based on collagen organization, with late phases of remodeling by untreated cells clustering strongly with early phases of remodeling by differentiating cells. The experiments were repeated three times to conclude that the metrics could successfully identify critical phases of collagen remodeling that were dependent upon cooperativity within the cell population.Conclusions/Significance
Definition of early metrics that are able to predict long-term functionality by linking engineered tissue structure to function is an important step toward optimizing biomaterials for the purposes of regenerative medicine. 相似文献47.
The effect of temperature and benzalkonium chloride (BAC) on nitrate reduction was investigated in batch assays using a mixed nitrate reducing culture. Nitrate was transformed completely, mainly through denitrification, to dinitrogen at 5, 10, 15 and 22 °C. In the absence of BAC, reduction of individual nitrogen oxides had different susceptibility to temperature and transient nitrite accumulation was observed at low temperatures. When the effect of BAC was tested up to 100 mg/L from 5 to 22 °C, denitrification was inhibited at and above 50 mg BAC/L with transient nitrite accumulation at all temperatures. The effect of BAC was described by a competitive inhibition model. Nitrite reduction was the denitrification step most susceptible to BAC, especially at low temperatures. BAC was not degraded during the batch incubation and was mostly biomass-adsorbed. Overall, this study shows that low temperatures exacerbate the BAC inhibitory effect, which in turn is controlled by adsorption to biomass. 相似文献
48.
R. A. Jones J. A. Gandier J. Thibault F. H. Tezel 《Biotechnology and Bioprocess Engineering》2011,16(3):531-541
To alleviate the ethanol inhibition of Escherichia coli KO11 (ATCC 55124), during fermentation, online ethanol sequestration was achieved using F-600 activated carbon. Two separate
schemes were tested, one involving direct addition of activated carbon to the fermentation flask for the purpose of in-situ
adsorption and a second involving an externally located activated carbon packed bed. For the in-situ ethanol adsorption experiments, varying amounts of adsorbent were added to the medium at the start of the fermentation. The
addition of the activated carbon in the fermentation broth resulted in increased glucose utilization and ethanol production
for all flasks containing activated carbon. For the control flasks, approximately 75% of the available substrate was utilized
before the fermentation was inhibited. The entire glucose supply of flasks containing activated carbon was depleted. Ethanol
production was also increased from 28 g/L for the control containing no activated carbon to nearly 45 g/L (including the ethanol
in the adsorbed phase) for the flasks containing activated carbon. The implementation of an externally located packed bed
adsorber for the purpose of on-line ethanol removal was tested over a number of adsorption cycles to evaluate the performance
of the adsorption bed and the ethanol productivity. Results indicate that maintaining ethanol fermentation medium concentrations
below 20 ∼ 30 g/L extends and enhances ethanol productivity. After 3 cycles over a period of 180 h, an additional 80% ethanol
was produced when compared to the control experiments, despite the suboptimal acidic pH of the medium. 相似文献
49.
High levels of heavy metals like copper ions in many industrial based effluents lead to serious environmental and health problems. Biosorption is a potential environmental biotechnology approach for biotreatment of aquatic sites polluted with heavy metal ions. Seaweeds have received great attention for their high bioremediation potential in recent years. However, the co-application of marine macroalgae for removal of heavy metals from wastewater is very limited. Thus, for the first time in literature, a coastal seaweed community composed of Chaetomorpha sp., Polysiphonia sp., Ulva sp. and Cystoseira sp. species was applied to remove copper ions from synthetic aqueous medium in this study. The biosorption experiments in batch mode were conducted to examine the effects of operating variables including pH, biosorbent amount, metal ion concentration and contact time on the biosorption process. The biosorption behavior of biosorbent was described by various equilibrium, kinetic and thermodynamic models. The biosorption of copper ions was strongly influenced by the operating parameters. The results indicated that the equilibrium data of biosorption were best modeled by Sips isotherm model. The values of mean free energy of biosorption computed from Dubinin-Radushkevich isotherm model and the standard Gibbs free energy change indicated a feasible, spontaneous and physical biotreatment system. The pseudo-second-order rate equation successfully defined the kinetic behavior of copper biosorption. The pore diffusion also played role in the control of biosorption process. The maximum copper uptake capacity of biosorbent was found to be greater than those of many other biosorbents. The obtained results revealed that this novel biosorbent could be a promising material for copper ion bioremediation implementations. 相似文献
50.