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61.
RNA binding proteins play significant roles in many bio-macromolecular systems. Aromatic amino acid residues are vital for several biological functions. In the present work, the influences of π–π interactions in RNA binding proteins are analyzed. There are a total of 3,396 π-residues in RNA binding proteins out of which 1,547, 1,241, and 608 are phenylalanine (Phe), tyrosine (Tyr), and tryptophan (Trp), respectively. Among these 945, 634, and 356 Phe, Tyr, and Trp residues, respectively, are involved in π–π interactions. The observations indicate that majority of the aromatic residues in RNA binding proteins are involved in π–π interactions. Side chain–side chain π–π interactions are the predominant type of interactions in RNA binding proteins. These π–π interactions stabilize the core regions within RNA binding proteins. π–π interacting residues are evolutionary conserved. Residue-wise analysis indicates that π–π interacting residues have higher long-range contacts and hence they are important in the global conformational stability of these proteins. 相似文献
62.
Vijay K. T. Alagappan Willem I. de Boer Virendra K. Misra Wolter J. Mooi Hari S. Sharma 《Cell biochemistry and biophysics》2013,67(2):219-234
Asthma and chronic obstructive pulmonary disease remain a global health problem, with increasing morbidity and mortality. Despite differences in the causal agents, both diseases exhibit various degrees of inflammatory changes, structural alterations of the airways leading to airflow limitation. The existence of transient disease phenotypes which overlap both diseases and which progressively decline the lung function has complicated the search for an effective therapy. Important characteristics of chronic airway diseases include airway and vascular remodeling, of which the molecular mechanisms are complex and poorly understood. Recently, we and others have shown that airway smooth muscle (ASM) cells are not only structural and contractile components of airways, rather they bear capabilities of producing large number of pro-inflammatory and mitogenic factors. Increase in size and number of blood vessels both inside and outside the smooth muscle layer as well as hyperemia of bronchial vasculature are contributing factors in airway wall remodeling in patients with chronic airway diseases, proposing for the ongoing mechanisms like angiogenesis and vascular dilatation. We believe that vascular changes directly add to the airway narrowing and hyper-responsiveness by exudation and transudation of proinflammatory mediators, cytokines and growth factors; facilitating trafficking of inflammatory cells; causing oedema of the airway wall and promoting ASM accumulation. One of the key regulators of angiogenesis, vascular endothelial growth factor in concerted action with other endothelial mitogens play pivotal role in regulating bronchial angiogenesis. In this review article we address recent advances in pulmonary angiogenesis and remodelling that contribute in the pathogenesis of chronic airway diseases. 相似文献
63.
Abstract The present paper deals with the embryological studies of ten species of Taraxacum, out of which nine polyploid species are apomictic and one diploid species T. wallichii shows normal sexual behaviour. Occasional formation of normal megaspore tetrads and triads are observed in tetraploid and triploid species. Autonomous development of endosperm from the secondary nucleus seems to be the rule. The growth of endosperm is relatively slow. 相似文献
64.
Ravi Ranjan Rakesh Kumar Singh Thirupathi Yasotha Manish Kumar Kuldeep Kumar Renu Singh Monzamul Houque Vijay Prakash Mourya Gyanendra Singh Mihir Sarkar Bikash Chandra Das Sadhan Bag 《In vitro cellular & developmental biology. Animal》2013,49(7):486-491
The present study was conducted to see the in vivo developmental potency of caprine parthenogenetic embryos generated in a modified way. The good quality caprine oocytes were matured in presence of cytochalasin B (CCB) and then activated by 7% ethanol followed by 2 mM 6-dimethyl amino purine (6-DMAP) and embryo development was recorded. Early stage parthenogenetic embryos (two to four cells) were surgically transferred in recipients (10). The pregnancy diagnosis was done by nonreturn to oestrus, ultrasonography (USG), and progesterone estimation. The levels of progesterone were above normal values (1 ng/ml) of pregnancy and fall below the level of pregnancy just before retuned to oestrus. Progesterone profile revealed that out of ten recipients (G1–G10), four goats (G1, G2, G3, and G5) returned to oestrus after 43?±?7.29 (Mean?±?SE) d of embryo transfer and six goats (G4, G6, G7, G8, G9, and G10) did not return to cycle even after 70 d of embryo transfer. In three recipients (G4, G5, and G6), the USG on day 40 revealed that there was fluid filled uterine body with solid fetus-like structure. These might be dead fetus and had started resorption. The progesterone profile also corroborated the assumption of pregnancy in these animals. Authors believe that this may be the first report on in vivo diploid parthenogenetic embryo development in caprine species. 相似文献
65.
β-lactam group of antibiotics is the most widely used therapeutic molecules for treating bacterial infections. The main mode of bacterial resistance to β-lactams is by β-lactamases. In the present study, we report our results on the role of cation–π interactions in β-lactamases and their environmental preferences. The number of interactions formed by arginine is higher than lysine in the cationic group, while tyrosine is comparatively higher than phenylalanine and tryptophan in the π group. Our results indicate that cation–π interactions might play an important role in the global conformational stability of β-lactamases. 相似文献
66.
67.
Black Spot: a platform for automated and rapid estimation of leaf area from scanned images 总被引:1,自引:0,他引:1
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
68.
Sangwoo Kim Kyowon Jeong Kunal Bhutani Jeong Ho Lee Anand Patel Eric Scott Hojung Nam Hayan Lee Joseph G Gleeson Vineet Bafna 《Genome biology》2013,14(8):R90
Detection of somatic variation using sequence from disease-control matched data sets is a critical first step. In many cases including cancer, however, it is hard to isolate pure disease tissue, and the impurity hinders accurate mutation analysis by disrupting overall allele frequencies. Here, we propose a new method, Virmid, that explicitly determines the level of impurity in the sample, and uses it for improved detection of somatic variation. Extensive tests on simulated and real sequencing data from breast cancer and hemimegalencephaly demonstrate the power of our model. A software implementation of our method is available at http://sourceforge.net/projects/virmid/. 相似文献
69.
70.
Min Xia Daxin Chen Valeria Endresz Ildiko Faludi Andrea Szabo Eva Gonczol Vijay Kakkar Xinjie Lu 《PloS one》2013,8(12)