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61.
The aim of this research work was to investigate a series of novel 5,6-diaryl-1,2,4-triazines (3a3q) containing 3-morpholinoethylamine side chain, and to address their antiplatelet activity by in vitro, ex vivo and in vivo methods. All compounds were synthesized by environment benign route and their structures were unambiguously confirmed by spectral data. Compounds (3l) and (3m) were confirmed by their single crystal X-ray structures. Out of all the synthesized compounds, 10 were found to be more potent in vitro than aspirin; six of them were found to be prominent in ex vivo assays and one compound (3d) was found to have the most promising antithrombotic profile in vivo. Moreover, compound (3d) demonstrated less ulcerogenicity in rats as compared to aspirin. The selectivity of the most promising compound (3d) for COX-1 and COX-2 enzymes was determined with the help of molecular docking studies and the results were correlated with the biological activity.  相似文献   
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Leaf area and its derivatives (e.g. specific leaf area) are widely used in ecological assessments, especially in the fields of plant–animal interactions, plant community assembly, ecosystem functioning and global change. Estimating leaf area is highly time-consuming, even when using specialized software to process scanned leaf images, because manual inputs are invariably required for scale detection and leaf surface digitisation. We introduce Black Spot Leaf Area Calculator (hereafter, Black Spot), a technique and stand-alone software package for rapid and automated leaf area assessment from images of leaves taken with standard flatbed scanners. Black Spot operates on comprehensive rule-sets for colour band ratios to carry out pixel-based classification which isolates leaf surfaces from the image background. Importantly, the software extracts information from associated image meta-data to detect image scale, thereby eliminating the need for time-consuming manual scale calibration. Black Spot’s output provides the user with estimates of leaf area as well as classified images for error checking. We tested this method and software combination on a set of 100 leaves of 51 different plant species collected from the field. Leaf area estimates generated using Black Spot and by manual processing of the images using an image editing software generated statistically identical results. Mean error rate in leaf area estimates from Black Spot relative to manual processing was ?0.4 % (SD = 0.76). The key advantage of Black Spot is the ability to rapidly batch process multi-species datasets with minimal user effort and at low cost, thus making it a valuable tool for field ecologists.  相似文献   
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Chromatin organization has a fundamental impact on the whole spectrum of genomic functions. Quantitative characterization of the chromatin structure, particularly at submicron length scales where chromatin fractal globules are formed, is critical to understanding this structure-function relationship. Such analysis is currently challenging due to the diffraction-limited resolution of conventional light microscopy. We herein present an optical approach termed inverse spectroscopic optical coherence tomography to characterize the mass density fractality of chromatin, and we apply the technique to observe chromatin decompaction in live cells. The technique makes it possible for the first time, to our knowledge, to sense intracellular morphology with length-scale sensitivity from ∼30 to 450 nm, thus primarily probing the higher-order chromatin structure, without resolving the actual structures. We used chromatin decompaction due to inhibition of histone deacytelases and measured the subsequent changes in the fractal dimension of the intracellular structure. The results were confirmed by transmission electron microscopy and confocal fluorescence microscopy.  相似文献   
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A 59-year-old man was diagnosed with urothelial carcinoma involving an isolated cerebellar metastasis after presenting to the emergency department for headache complaints. After selective surgical excision of the symptomatic brain lesion and delayed cystectomy due to intractable hematuria, he survived 11 years without evidence of recurrence or subsequent systemic chemotherapy. He eventually expired after delayed recurrence in the lung, supraclavicular lymph node, and brain. To our knowledge, this is the only case of prolonged survival from urothelial carcinoma after selective surgical extirpation of the primary and metastatic lesion without subsequent systemic chemotherapy.Key words: Bladder cancer, Cystectomy, Metastasis, Urothelial carcinomaUsually, brain metastasis of bladder urothelial carcinoma is associated with widespread systemic disease and/or multiple brain lesions. It is exceedingly rare to have bladder cancer metastasize to the brain without evidence of additional systemic manifestations.1 As with other forms of distant urothelial carcinoma metastasis, brain metastasis is associated with poor prognosis, with survival often less than 14 months in those with solitary brain lesions.2 We report an isolated bladder urothelial carcinoma metastasis to the cerebellum with an 11-year survival fol-lowing extirpative therapy of both the primary lesion and brain metastasis.  相似文献   
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Spinal cord injury (SCI), depending on the severity of injury, leads to neurological dysfunction and paralysis. Methylprednisolone, the only currently available therapy renders limited protection in SCI. Therefore, other therapeutic agents must be tested to maximize neuroprotection and functional recovery. Previous data from our laboratory indicate that estrogen (17β-estradiol) at a high dose may attenuate multiple damaging pathways involved in SCI and improve locomotor outcome. Since use of high dose estrogen may have detrimental side effects and therefore may never be used in the clinic, the current study investigated the efficacy of this steroid hormone at very low doses in SCI. In particular, we tested the impact of dosing (1–10 μg/kg), mode of delivery (intravenous vs. osmotic pump), and delay in estrogen application (15 min–4 h post-SCI) on microgliosis and neuronal death in acute SCI in rats. Treatment with 17β-estradiol (1–10 μg/kg) significantly reduced microglial activation and also attenuated apoptosis of neurons compared to untreated SCI animals. The attenuation of cell death and inflammation by estrogen was observed regardless of mode and time of delivery following injury. These findings suggest estrogen as a potential agent for the treatment of individuals with SCI.  相似文献   
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Pho regulon is a highly evolved and conserved mechanism across the microbes to fulfil their phosphate need. In this study, 52 proteobacteria genomes were analyzed for the presence of phosphorus acquisition genes, their pattern of arrangement and copy numbers. The diverse genetic architecture of the Pho regulon genes indicates the evolutionary challenge of nutrient limitation, particularly phosphorus, faced by bacteria in their environment. The incongruence between the Pho regulon proteins phylogeny and species phylogeny along with the presence of additional copies of pstS and pstB genes, having cross similarity with other genera, suggest the possibility of horizontal gene transfer event. The substitution rate analysis and multiple sequence alignment of the Pho regulon proteins were analyzed to gain additional insight into the evolution of the Pho regulon system. This comprehensive study confirms that genes perform the regulatory function (phoBR) were vertically inherited, whereas interestingly, genes whose product involved in direct interaction with the environment (pstS) acquired by horizontal gene transfer. The substantial amino acid substitutions in PstS most likely contribute to the successful adaptation of bacteria in different ecological condition dealing with different phosphorus availability. The findings decipher the intelligence of the bacteria which enable them to carry out the targeted alteration of genes to cope up with the environmental condition.  相似文献   
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In this study, we conducted an epigenome-wide association study of metabolic syndrome (MetS) among 846 participants of European descent in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN). DNA was isolated from CD4+ T cells and methylation at ~470,000 cytosine-phosphate-guanine dinucleotide (CpG) pairs was assayed using the Illumina Infinium HumanMethylation450 BeadChip. We modeled the percentage methylation at individual CpGs as a function of MetS using linear mixed models. A Bonferroni-corrected P-value of 1.1 x 10−7 was considered significant. Methylation at two CpG sites in CPT1A on chromosome 11 was significantly associated with MetS (P for cg00574958 = 2.6x10-14 and P for cg17058475 = 1.2x10-9). Significant associations were replicated in both European and African ancestry participants of the Bogalusa Heart Study. Our findings suggest that methylation in CPT1A is a promising epigenetic marker for MetS risk which could become useful as a treatment target in the future.  相似文献   
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