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31.
32.
The effect of p-nitrophenol (PNP) concentration with or without glucose and yeast extract on the growth and biodegradative capacity of Ralstonia eutropha was examined. The chemical constituents of the culture medium were modeled using a response surface methodology. The experiments were performed according to the central composite design arrangement considering PNP, glucose and yeast extract as the selected variables whose influences on the degradation was evaluated (shaking in reciprocal mode, temperature of 30°C, pH 7 and test time of about 9 h). Quadratic polynomial regression equations were used to quantitatively explain variations between and within the models (responses: the biodegradation capacity and the biomass formation). The coefficient of determination was high (R adjusted2 = 0.9783), indicating the constructed polynomial model for PNP biodegradative capacity explains the variation between the regressors fairly well. A PNP removal efficiency of 74.5% occurred within 9 h (15 mg/L as the initial concentration of PNP with use of yeast extract at 0.5 g/L).  相似文献   
33.
The effect of different NaCl concentrations (control, 2, 4 and 6 dS/m) and three harvesting times in different seasons including spring (9 April), summer (5 July), and fall (23 September) was evaluated on essential oil (EO) yield, composition, phenolic, flavonoid content, and antioxidant activity of myrtle. Essential oil yield ranged from 0.2% in control and fall to 1.6% in moderate salinity (4 dS/m) and spring season. The main constituents obtained from gas chromatography/mass spectrometry analysis were α‐pinene, 1,8‐cineole, limonene, linalool, α‐terpineol, and linalyl acetate in which α‐pinene ranged from 11.70% in moderate and fall to 30.99% in low salinity (2 dS/m) and spring, while 1,8‐cineole varied from 7.42% in high salinity (6 dS/m) and summer to 15.45% in low salinity and spring, respectively. Salt stress also resulted in an increase in total phenolic, flavonoid content, and antioxidant activity. The highest antioxidant activity based on DPPH radical scavenging activity, reducing power (FTC) and β‐carotene/linoleic acid model systems was found in plants harvested in spring and summer in high stress condition. The lowest IC50 values obtained in 6 dS/m in spring (375.23 μg/ml) followed by summer (249.41 μg/ml) and fall (618.38 μg/ml). Eight major phenolic and flavonoid compounds were determined in three harvesting times using high performance liquid chromatography analysis. In overall, late harvesting time of myrtle in fall can lead to reduce the most of major EO components, while it can improve the amount of phenolic acids.  相似文献   
34.
The Wnt pathway tumor-suppressor protein Axin coordinates the formation of a critical multiprotein destruction complex that serves to downregulate β-catenin protein levels, thereby preventing target gene activation. Given the lack of structural information on some of the major functional parts of Axin, it remains unresolved how the recruitment and positioning of Wnt pathway kinases, such as glycogen synthase kinase 3β, are coordinated to bring about β-catenin phosphorylation. Using various biochemical and biophysical methods, we demonstrate here that the central region of Axin that is implicated in binding glycogen synthase kinase 3β and β-catenin is natively unfolded. Our results support a model in which the unfolded nature of these critical scaffolding regions in Axin facilitates dynamic interactions with a kinase and its substrate, which in turn act upon each other.  相似文献   
35.
Molecular Biology Reports - Both extreme usage of water in agriculture i.e., drought and flooding affect physiological and growth aspects of the plant as well as gene expression undertaken in water...  相似文献   
36.
Glioblastoma multiforme (GBM) is a malignant brain cancer that causes high mortality in patients. GBM responds weakly to the common cancer treatments such as chemotherapy and radiotherapy and even surgery. Carboplatin is an alkylating agent widely used to treat cancer. However, resistance to this drug is a common problem in its use in cancer treatment. Concomitant exposure to extremely low-frequency electromagnetic fields (ELF-EMFs) and carboplatin is one unexplored possibility for overcoming this resistance. Indeed, many lines of evidence show that EMF affects cancer cells and drug action. In this study, we evaluated the effect of concomitant administration of carboplatin and EMF (50 Hz, 70 G) and also concomitant administration of carboplatin and static magnetic field (SMF) (70 G) on human glioma cell line (U-87). The results showed that cotreatment reduced the efficiency of carboplatin in U-87 cells, by decreasing caspase-3 in comparison to drug groups. Overall, EMF reduced the apoptotic effect of carboplatin, possibly through a redox regulation mechanism. Therefore, we have to avoid coadministration of magnetic field (MF) and carboplatin in tumor area, because the MF decreased the toxicity of the drug. However, further studies are needed to reveal the action mechanism of this combination therapeutic method.  相似文献   
37.
This article reviews some of the aspects of single cell oil (SCO) production using solid-state fermentation (SSF) by fungi of the genus Mortierella. This article provides an overview of the advantages of SSF for SCO formation by the aforementioned fungus and demonstrates that the content of the polyunsaturated fatty acids (PUFA) depend on the type of fermentation media and culture conditions. Process variables that influence lipid accumulation by Mortierella spp. and the profile of the fatty acids are discussed, including incubation temperature, time, aeration, growth phase of the mycelium, particle size of the substrate, carbon to nitrogen ratio, initial moisture content and pH as well as supplementation of the substrate with nitrogen and oil. Finally, the article highlights future research trends for the scaled-up production of PUFAs in SSF.  相似文献   
38.

Objectives and Backgrounds

Cardiovascular events occure as a result of various risk factors, such as uric acid (UA), inflammation, hormones and other materials that induce C- reactive protein (CRP) expression. These factors lead to complement activation, and endothelial damages. Damaged endothelial cells release heparan sulfate which inhibits tissue factor activity and von Willed brand factor (VWVF) and causes aggregation. Finally this cascade of events cause platelets aggregation and leads to heart ischemia and cardiovascular events.

Discussion

Anti-platelet therapy is an interesting premise. Anti-platelet resistance patients and bleeding as a result of using ticagrelor and prasugrel should be considered in this treatment methods. Anti-platelet drugs such as clopidogrel are prescribed in cardiovascular events. Platelets have VWF receptors and P2Y12 receptors on their surface, and thus, targeting these receptors can be useful in treatment. The active metabolites of clopidogrel bind to P2Y12R and inhibit ADP binding; thus, clopidogrel inhibits aggregation by interfering in several events as a result of the inhibition of ADP attachment to P2Y12R of the platelet. However, the polymorphisms of P2Y12 and other genes mentioned in Table 1 showed treatment resistance in anti-platelet therapy, highlighting that these SNPs can be helpful in anti-platelet therapy.

Conclusion

The knowledge of these SNPs may decrease the number of unwanted effects that endanger patients with cardiovascular diseases and avoids ineffective anti-platelet therapy in several patients. Clopidogrel, ticagrelor, prasugrel, and aspirin and CYP2C19 and their SNPs are very important subjects in anti-platelet therapy. To present the importance of using pharmacogenetics in anti-platelet therapy, we discuss here the association between these drugs and the SNPs for therapeutic resistance.
  相似文献   
39.
The cardiac neuronal nitric-oxide synthase (nNOS) has been described as a modulator of cardiac contractility. We have demonstrated previously that isoform 4b of the sarcolemmal calcium pump (PMCA4b) binds to nNOS in the heart and that this complex regulates β-adrenergic signal transmission in vivo. Here, we investigated whether the nNOS-PMCA4b complex serves as a specific signaling modulator in the heart. PMCA4b transgenic mice (PMCA4b-TG) showed a significant reduction in nNOS and total NOS activities as well as in cGMP levels in the heart compared with their wild type (WT) littermates. In contrast, PMCA4b-TG hearts showed an elevation in cAMP levels compared with the WT. Adult cardiomyocytes isolated from PMCA4b-TG mice demonstrated a 3-fold increase in Ser16 phospholamban (PLB) phosphorylation as well as Ser22 and Ser23 cardiac troponin I (cTnI) phosphorylation at base line compared with the WT. In addition, the relative induction of PLB phosphorylation and cTnI phosphorylation following isoproterenol treatment was severely reduced in PMCA4b-TG myocytes, explaining the blunted physiological response to the β-adrenergic stimulation. In keeping with the data from the transgenic animals, neonatal rat cardiomyocytes overexpressing PMCA4b showed a significant reduction in nitric oxide and cGMP levels. This was accompanied by an increase in cAMP levels, which led to an increase in both PLB and cTnI phosphorylation at base line. Elevated cAMP levels were likely due to the modulation of cardiac phosphodiesterase, which determined the balance between cGMP and cAMP following PMCA4b overexpression. In conclusion, these results showed that the nNOS-PMCA4b complex regulates contractility via cAMP and phosphorylation of both PLB and cTnI.Neuronal nitric-oxide synthase (nNOS)5 is involved in a number of key processes in cardiomyocytes including calcium cycling (1), the β-adrenergic contractile response (2, 3), post-infarct left ventricular remodeling (4), and the regulation of redox equilibrium (5). Moreover, a polymorphism in an nNOS-interacting protein, CAPON, has been found to form a quantitative trait for the determination of the QT interval in humans (6), whereas a mutation in α1-syntrophin (SNTA1), another interacting partner of nNOS, has been associated with long QT syndrome (7). The signaling events downstream of the nNOS-CAPON (8) and nNOS-SNTA1 (7) complexes, which are responsible for mediating cardiac repolarization and sodium current respectively, have been elucidated. The nNOS-containing protein complex is therefore of immediate relevance to human pathology.In recent years, we have shown that the sarcolemmal calcium pump, which ejects calcium to the extracellular compartment (reviewed in Refs. 9 and 10), is an important molecule involved in signal regulation and transmission in the heart (11). We have demonstrated that isoform 4b of the sarcolemmal calcium pump (also known as PMCA4b for plasma membrane calcium/calmodulin-dependent ATPase 4b) modulates signaling through a tight molecular interaction with nNOS, leading to the modulation of β-adrenergic responsiveness in the heart (12). However, the events following signaling through the PMCA4b-nNOS complex remain unknown.In myocardial cells, nNOS has been localized to the sarcolemma (13), sarcoplasmic reticulum (2), and mitochondria (14), and translocation between compartments has been demonstrated (15). It has been speculated that these various localizations provide specificity to NO signaling, but the exact mechanisms have yet to be elucidated. In this study, we show a mechanism by which one fraction of nNOS serves highly specific functions through binding to PMCA4b. As PMCA4b is confined to the sarcolemma and is a calcium pump, it is the first identified protein to fulfill these aggregate functions. 1) It acts as an anchoring protein; 2) it regulates nNOS activity; and 3) it modulates a process at the plasma membrane, i.e. β-adrenergic signaling.  相似文献   
40.
Oxidative stress plays a crucial role in the pathogenesis of multiple sclerosis (MS). Previous studies have shown that oxidative stress is one of the main underlying mechanisms of arsenic-induced cellular damage. The aim of this study was to assess the serum levels of arsenic and its relationship with lipid peroxidation in MS patients from Tabriz, as the third polluted city of Iran. The study population included 38 MS female patients and 38 age-matched healthy controls. Serum malondialdehyde (MDA) and arsenic levels were measured using thiobarbituric acid reactive substances (TBARS) assay and electrothermal atomic absorption spectrometry, respectively. The results showed that the arsenic (P?<?0.01) and MDA (P?=?0.03) levels were significantly higher in patients with MS than those in control. Moreover, serum levels of arsenic and MDA were positively correlated in MS patients. The elevated levels of serum arsenic might explain the increased oxidative stress in MS patients. We suggest that high arsenic levels in serum may lead to MS development, and therefore, exposure to this metal should be limited.  相似文献   
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