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171.
Molecular Biology Reports - The aim of this study was to explore the association between alpha-thalassemia, fetal hemoglobin, hematological indices, and clinical adverse events in Angolan sickle...  相似文献   
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Plant Molecular Biology Reporter - Manihot esculenta Crantz is originally from the Amazon region of Brazil, which has the highest genetic diversity. Due to the wide adaptation of cassava to the...  相似文献   
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Abstract

Sirtuin 2 is a key enzyme in gene expression regulation that is often associated with tumor proliferation control and therefore is a relevant anticancer drug target. Anilinobenzamide derivatives have been discussed as selective sirtuin 2 inhibitors and can be developed further. In the present study, hologram and three-dimensional quantitative structure–activity relationship (HQSAR and 3D-QSAR) analyses were employed for determining structural contributions of a compound series containing human sirtuin-2-selective inhibitors that were then correlated with structural data from the literature. The final QSAR models were robust and predictive according to statistical validation (q2 and r2pred values higher than 0.85 and 0.75, respectively) and could be employed further to generate fragment contribution and contour maps. 3D-QSAR models together with information about the chemical properties of sirtuin 2 inhibitors can be useful for designing novel bioactive ligands.

Communicated by Ramaswamy H. Sarma  相似文献   
175.
The formation of specific protein-protein interactions is often a key to a protein's function. During complex formation, each protein component will undergo a change in the conformational state, for some these changes are relatively small and reside primarily at the sidechain level; however, others may display notable backbone adjustments. One of the classic problems in the protein-docking field is to be able to a priori predict the extent of such conformational changes. In this work, we investigated three protocols to find the most suitable input structure conformations for cross-docking, including a robust sampling approach in normal mode space. Counterintuitively, knowledge of the theoretically best combination of normal modes for unbound-bound transitions does not always lead to the best results. We used a novel spatial partitioning library, Aether Engine (see Supplementary Materials ), to efficiently search the conformational states of 56 receptor/ligand pairs, including a recent CAPRI target, in a systematic manner and selected diverse conformations as input to our automated docking server, SwarmDock, a server that allows moderate conformational adjustments during the docking process. In essence, here we present a dynamic cross-docking protocol, which when benchmarked against the simpler approach of just docking the unbound components shows a 10% uplift in the quality of the top docking pose.  相似文献   
176.
Hypertension is a major and highly prevalent risk factor for various diseases. Among the most frequently prescribed antihypertensive first-line drugs are synthetic angiotensin I-converting enzyme inhibitors (ACEI). However, since  their use in hypertension therapy has been linked to various side effects, interest in the application of food-derived ACEI peptides (ACEIp) as antihypertensive agents is rapidly growing. Although promising, the industrial production of ACEIp through conventional methods such as chemical synthesis or enzymatic hydrolysis of food proteins has been proven troublesome. We here provide an overview of current antihypertensive therapeutics, focusing on ACEI, and illustrate how biotechnology and bioengineering can overcome the limitations of ACEIp large-scale production. Latest advances in ACEIp research and current genetic engineering-based strategies for heterologous production of ACEIp (and precursors) are also presented. Cloning approaches include tandem repeats of single ACEIp, ACEIp fusion to proteins/polypeptides, joining multivariate ACEIp into bioactive polypeptides, and producing ACEIp-containing modified plant storage proteins. Although bacteria have been privileged ACEIp heterologous hosts, particularly when testing for new genetic engineering strategies, plants and microalgae-based platforms are now emerging. Besides being generally safer, cost-effective and scalable, these “pharming” platforms can perform therelevant posttranslational modifications and produce (and eventually deliver) biologically active protein/peptide-based antihypertensive medicines.  相似文献   
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Although at present, there is a high incidence of prostate cancer, particularly in the Western world, mortality from this disease is declining and occurs primarily only from clinically significant late stage tumors with a poor prognosis. A major current focus of this field is the identification of new biomarkers which can detect earlier, and more effectively, clinically significant tumors from those deemed “low risk”, as well as predict the prognostic course of a particular cancer. This strategy can in turn offer novel avenues for targeted therapies. The large family of Receptor Tyrosine Kinases, the Ephs, and their binding partners, the ephrins, has been implicated in many cancers of epithelial origin through stimulation of oncogenic transformation, tumor angiogenesis, and promotion of increased cell survival, invasion and migration. They also show promise as both biomarkers of diagnostic and prognostic value and as targeted therapies in cancer. This review will briefly discuss the complex roles and biological mechanisms of action of these receptors and ligands and, with regard to prostate cancer, highlight their potential as biomarkers for both diagnosis and prognosis, their application as imaging agents, and current approaches to assessing them as therapeutic targets. This review demonstrates the need for future studies into those particular family members that will prove helpful in understanding the biology and potential as targets for treatment of prostate cancer.  相似文献   
179.
The fig (Ficus L.) infructescence, called syconium, is a receptacle with an apical opening, the ostiole, closed by bracts. The ostiolar bracts produce an exudate, which is rather conspicuous in some species. It has not been histochemically analyzed yet, and the structures responsible for its production are still unknown. Some wild growing species of Ficus from Brazil produce high amounts of this ostiolar exudate. Ficus enormis (Mart. ex Miq.) Miq. grows as trees or shrubs in the Atlantic rainforest. Our goal was to identify the secretory structures present in the inflorescence and, to characterize histochemically the ostiolar tissues and exudates. Syconia samples of F. enormis were processed and stained according to the usual techniques in plant anatomy. The morphological analysis revealed different types of bracts, one type specialized in secretion, another showing transitional characteristics between secretory and non-secreting bracts, and a third one being non-secreting. They are designated as secretory ostiolar bracts, transitional bracts and wall bracts. The floral bracteoles, digital-shaped colleters present in the ostiole, at the syconium axis and at the flower receptacle, were also analyzed. All have similar structure, like finger-shaped secretory trichomes. The colleters present among ostiolar bracts may contribute to production and composition of the ostiole exudate.  相似文献   
180.
Tyrosinemia type II, also known as Richner–Hanhart syndrome, is an autosomal recessive inborn error of metabolism caused by a deficiency of hepatic cytosolic tyrosine aminotransferase, and is associated with neurologic and development difficulties in numerous patients. Considering that the mechanisms underlying the neurological dysfunction in hypertyrosinemic patients are poorly known and that studies demonstrated that high concentrations of tyrosine provoke oxidative stress in vitro and in vivo in the cerebral cortex of rats, in the present study we investigate the oxidative stress parameters (enzymatic antioxidant defenses, thiobarbituric acid-reactive substances and protein carbonyl content) in cerebellum, hippocampus and striatum of 30-old-day rats after acute administration of l-tyrosine. Our results demonstrated that the acute administration of l-tyrosine increased the thiobarbituric acid reactive species levels in hippocampus and the carbonyl levels in cerebellum, hippocampus and striatum. In addition, acute administration of l-tyrosine significantly decreased superoxide dismutase activity in cerebellum, hippocampus and striatum, while catalase was increased in striatum. In conclusion, the oxidative stress may contribute, along with other mechanisms, to the neurological dysfunction characteristic of hypertyrosinemia and the administration of antioxidants may be considered as a potential adjuvant therapy for tyrosinemia, especially type II.  相似文献   
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