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61.
Molineria capitulata is an ornamental plant that has traditionally been used to treat several chronic diseases. The present study was designed to examine the antioxidant, cytotoxic, thrombolytic, anti-inflammatory, and analgesic activities of a methanolic extract of M. capitulata leaves (MEMC) using both experimental and computational models. Previously established protocols were used to perform qualitative and quantitative phytochemical screening in MEMC. A computational study, including molecular docking and ADME/T analyses, was performed. The quantitative phytochemical analysis revealed the total phenolic and flavonoid contents as 148.67 and 24 mg/g, respectively. Antioxidant activity was assessed by examining the reducing power of MEMC, resulting in absorbance of 1.87 at 400 µg/mL, demonstrating a strong reduction capacity. The extract exhibited significant protection against blood clotting and showed the highest protein denaturation inhibition at 500 µg/mL. In both the acetic acid-induced writhing and formalin-induced paw-licking models, MEMC resulted in significant potential pain inhibition in mice. In the computational analysis, 4-hydroxybenzaldehyde, orcinol glucoside, curcapital, crassifogenin C, and 2,6-dimethoxy-benzoic acid displayed a strong predictive binding affinity against the respective receptors. These findings indicated that M. capitulata possesses significant pharmacological activities to an extent supported by computational studies.  相似文献   
62.
During restoration of blood flow of the ischemic heart induced by coronary occlusion, free radicals cause lipid peroxidation with myocardial injury. Lipid peroxidation end-products, such as malondialdehyde (MDA), have been used to assess oxygen free radical-mediated injury of the ischemic-reperfused (I/R) myocardium in rats. This experimental study assessed the preventive effect of caffeic acid phenthyl ester (CAPE), antioxidant, on I/R-induced lipid peroxidation in the rat heart. We are also interested in the role of CAPE on glutathione (GSH) levels, an antioxidant whose levels are influenced by oxidative stress. I/R leads to the depletion of GSH which is the major intracellular nonprotein sulphydryl and plays an important role in the maintenance of cellular proteins and lipid in their functional state and acts primarily to protect these important structures against the threat of oxidation. In addition, we also examined morphologic changes in the heart by using light microscopy. The left coronary artery was occluded for 30 min and then reperfused for 120 min more before the experiment was terminated. CAPE (50 M kg–1) was administered 10 min prior to ischemia and during occlusion by infusion. At the end of the reperfusion period, rats were sacrificed, and the heart was quickly removed for biochemical determination and histopathological analysis. I/R was accompanied by a significant increase in MDA production and decrease in GSH content in the rat heart. Administration of CAPE reduced MDA production and prevented depletion of GSH content. These beneficial changes in these biochemical parameters were also associated with parallel changes in histopathological appearance. These findings imply that I/R plays a causal role in heart injury due to overproduction of oxygen radicals or insufficient antioxidant and CAPE exert cardioprotective effects probably by the radical scavenging and antioxidant activities.  相似文献   
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64.
Demir  Ahmet U.  Ardic  Sadik  Firat  Hikmet  Karadeniz  Derya  Aksu  Murat  Ucar  Zeynep Zeren  Sevim  Serhan  Ozgen  Fuat  Yilmaz  Hikmet  Itil  Oya  Peker  Yuksel  Aygul  Fatma  Kiran  Sibel  Gelbal  Selahattin  Cepni  Zafer  Akozer  Mehmet 《Sleep and biological rhythms》2015,13(4):298-308
Sleep and Biological Rhythms - Sleep disorders constitute an important public health problem. Prevalence of sleep disorders in Turkish adult population was investigated in a nationwide...  相似文献   
65.
Leptin is a protein hormone which plays a critical role in the regulation of both body-weight through reducing food intake and stimulating energy expenditure. Several polymorphisms in leptin gene (LEP), which encodes for leptin, have been described. However, its association with obesity is still controversial. Therefore, in the present study, we aimed to investigate whether LEP c.-2548 G>A polymorphism was associated with serum leptin levels, lipid parameters, and body mass index in Turkish obese patients. Forty-seven obese patients and 48 healthy individuals were included in the study. Blood samples were collected for DNA extraction. LEP c.-2548 G>A polymorphism were detected using polymerase chain reaction–restriction fragment length polymorphism technique. Serum leptin levels and lipid parameters were measured by ELISA and enzyme colorimetric assay techniques, respectively. GA or AA genotypes and A allele carrier frequencies of the c.-2548 G>A polymorphism in the LEP were higher in obese (38.3, 34.0 and 72.3 %) when compared with controls (14.6, 12.5, and 27.1 %; p = 0.011, 0.016, and 0.002, respectively). On the other hand, AA or AG genotypes were also related to increased serum leptin levels (p < 0.001) and body mass index (p < 0.0001). All these consequences showed that LEP -2548 AA or AG genotypes are important predictors for increased levels of leptin and BMI in Turkish obese patients and it may be a useful marker for obesity risk in our population.  相似文献   
66.
The physicochemical properties of tarhana soup produced with different dough treatments, fermentation times, and preservation methods were examined. Tarhana doughs were prepared with yogurt (control) or baker's yeast (Saccharomyces cerevisiae) and fermented for 3 days. Samples were taken at 24, 48, and 72 hr. Samples were then preserved via one of four methods: sun dried, dried in the shade, vacumn dried, and frozen. Frozen samples produced lower organic acid levels after 72 hr of fermentation in both control (0.68 g/100 g) and yeast (0.61 g/100 g) applications than samples that were dried (0.94 g/100 g control samples; 0.81 g/100 g samples with yeast). Increasing fermentation time resulted in a significant effect on the formation of organic acid in the tarhana (p < .01). At 72 hr of fermentation, total acidity increased 11%, 17%, and 23% for tarhana samples vacumn-dried, sun-dried, and dried in the shade, respectively. Preservation methods also affected the moisture, ash, crude protein, total acidity, pH, salt, fat, reducing sugar levels, and the sensory assestment of tarhana soup (p < .01). Sensory characteristics were not significantly affected by baker's yeast in any of the preservation methods used (p > .01). However, sensory scores for tarhana prepared from the samples dried in a sheltered area showed a reduction in color desireablilty as the fermentation time increased. The soup prepared from frozen tarhana (72 hr fermentation, with yeast) had the highest scores with respect to color, mouth feel, flavor, and overall acceptability. Vacuum-dried samples' scores in these areas were also high in comparison to the two other drying methods.  相似文献   
67.
In Vitro Cellular & Developmental Biology - Plant - Astragalus brachypterus Fischer (milkvetch) is a perennial medicinal plant in the family Fabaceae. Astragalus species have been utilized as...  相似文献   
68.
The last decade saw the advent of increasingly realistic epidemic models that leverage on the availability of highly detailed census and human mobility data. Data-driven models aim at a granularity down to the level of households or single individuals. However, relatively little systematic work has been done to provide coupled behavior-disease models able to close the feedback loop between behavioral changes triggered in the population by an individual's perception of the disease spread and the actual disease spread itself. While models lacking this coupling can be extremely successful in mild epidemics, they obviously will be of limited use in situations where social disruption or behavioral alterations are induced in the population by knowledge of the disease. Here we propose a characterization of a set of prototypical mechanisms for self-initiated social distancing induced by local and non-local prevalence-based information available to individuals in the population. We characterize the effects of these mechanisms in the framework of a compartmental scheme that enlarges the basic SIR model by considering separate behavioral classes within the population. The transition of individuals in/out of behavioral classes is coupled with the spreading of the disease and provides a rich phase space with multiple epidemic peaks and tipping points. The class of models presented here can be used in the case of data-driven computational approaches to analyze scenarios of social adaptation and behavioral change.  相似文献   
69.
Programmed death 1 (PD-1) is a potent inhibitor of T cell responses. PD-1 abrogates activation of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, but the mechanism remains unclear. We determined that during T cell receptor (TCR)/CD3- and CD28-mediated stimulation, PTEN is phosphorylated by casein kinase 2 (CK2) in the Ser380-Thr382-Thr383 cluster within the C-terminal regulatory domain, which stabilizes PTEN, resulting in increased protein abundance but suppressed PTEN phosphatase activity. PD-1 inhibited the stabilizing phosphorylation of the Ser380-Thr382-Thr383 cluster within the C-terminal domain of PTEN, thereby resulting in ubiquitin-dependent degradation and diminished abundance of PTEN protein but increased PTEN phosphatase activity. These effects on PTEN were secondary to PD-1-mediated inhibition of CK2 and were recapitulated by pharmacologic inhibition of CK2 during TCR/CD3- and CD28-mediated stimulation without PD-1. Furthermore, PD-1-mediated diminished abundance of PTEN was reversed by inhibition of ubiquitin-dependent proteasomal degradation. Our results identify CK2 as a new target of PD-1 and reveal an unexpected mechanism by which PD-1 decreases PTEN protein expression while increasing PTEN activity, thereby inhibiting the PI3K/Akt signaling axis.  相似文献   
70.
Niemann–Pick disease (NPD) is a lysosomal storage disorder that results from the deficiency of a lysosomal enzyme, acid sphingomyelinase. Niemann–Pick disease type A and B is caused by mutations in the sphingomyelin phosphodiesterase gene (SMPD1) coding for ASM. The aim of this study was to evaluate the spectrum of SMPD1 gene mutations in Turkish NPD patients and to study genotype–phenotype associations. We present a molecular analysis of 10 Turkish NPD type A/B patients. Four of the patients had type A and six had type B NPD. All mutant SMPD1 alleles were identified, including 5 different mutations, 1 of which was novel. These mutations included three missense mutations: c.409T>C (p.L137P), c.1262 A>G (p.H421R) and c.1552T>C (p.L549P), a common frameshift mutation in codon 189, identified in three patients, is caused by the deletion of the 567T, introducing a stop codon 65 amino acids downstream (p.P189fsX65), and a novel frameshift mutation c.1755delC (p.P585PfsX24) which was not reported previously.  相似文献   
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