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1.
Kunal Biswas Awdhesh Kumar Mishra Pradipta Ranjan Rauta Abdullah G. Al-Sehemi Mehboobali Pannipara Avik Sett Amra Bratovcic Satya Kumar Avula Tapan Kumar Mohanta Muthupandian Saravanan Yugal Kishore Mohanta 《International journal of molecular sciences》2022,23(2)
At present, the potential role of the AgNPs/endo-fullerene molecule metal nano-composite has been evaluated over the biosystems in-vitro. The intra-atomic configuration of the fullerene molecule (C60) has been studied in-vitro for the anti-proliferative activity of human breast adenocarcinoma (MDA-MB-231) cell lines and antimicrobial activity against a few human pathogens that have been augmented with the pristine surface plasmonic electrons and antibiotic activity of AgNPs. Furthermore, FTIR revealed the basic vibrational signatures at ~3300 cm−1, 1023 cm−1, 1400 cm−1 for O-H, C-O, and C-H groups, respectively, for the carbon and oxygen atoms of the C60 molecule. NMR studies exhibited the different footprints and magnetic moments at ~7.285 ppm, explaining the unique underlying electrochemical attributes of the fullerene molecule. Such unique electronic and physico-chemical properties of the caged carbon structure raise hope for applications into the drug delivery domain. The in-vitro dose-dependent application of C60 elicits a toxic response against both the breast adenocarcinoma cell lines and pathogenic microbes. That enables the use of AgNPs decorated C60 endo fullerene molecules to design an effective anti-cancerous drug delivery and antimicrobial agent in the future, bringing a revolutionary change in the perspective of a treatment regime. 相似文献
2.
Induction of apoptosis and apoptotic mediators in balb/C splenic lymphocytes by dietary n−3 and n−6 fatty acids 总被引:5,自引:0,他引:5
The present study was designed to investigate the effect of diatery n−6 and n−3 polyunsaturated fatty acids (PUFA) on anti-CD3
and anti-Fas antibody-induced apoptosis and its mediators in mouse spleen cells. Nutritionally adequate semipurified diets
containing either 5% w/w corn oil (n−6 PUFA) or fish oil (n−3 PUFA) were fed to weanling female Balb/C mice, and 24 wk later
mice were sacrificed. In n−3 PUFA-fed mice, serum and splenocyte lipid peroxides were increased by 20 and 28.3% respectively,
compared to n−6 PUFA-fed mice. Further, serum vitamin F levels were decreased by 50% in the n−3 PUFA-fed group, whereas higher
anti0Fas- and anti-CD3-induced apoptosis (65 and 66%) and necrosis (17 and 25%), compared to the n−6 PUFA-fed group, were
found when measured with Annexin V and propidium iodide staining, respectively. In addition, decreased Bcl-2 and increased
Fas-ligand (Fas-L) also were observed in the n−3 PUFA-fed group compared to the n−6 PUFA-fed group. No difference in the ratio
of splenocyte subsets nor their Fas expression was observed between the n−3 PUFA-fed and n−6 PUFA-fed groups, whereas decreased
proliferation of splenocytes was found in n−3 PUFA-fed mice compared to n−6 PUFA-fed mice. In conclusion, our results indicate
that dietary n−3 PUFA induces higher apoptosis by increasing the generation of lipid peroxides and elevating Fas-L expression
along with decreasing Bcl-2 expression. A reduced proliferative response of immune cells also was observed in n−3 PUFA-fed
mice. 相似文献
3.
Avula Edukondalu T. Sripathi Shaik Kareem Ahmmad Syed Rahman K. Sivakumar 《Journal of Electronic Materials》2017,46(2):808-816
Glass with compositions xK2O-(30 ? x)Li2O-10WO3-60B2O3 for 0 ≤ x ≤ 30 mol.% have been prepared using the normal melt quenching technique. The optical reflection and absorption spectra were recorded at room temperature in the wavelength range 300–800 nm. From the absorption edge studies, the values of the optical band gap (E opt) and Urbach energy (ΔE) have been evaluated. The values of E opt and ΔE vary non-linearly with composition parameter, showing the mixed alkali effect. The dispersion of the refractive index is discussed in terms of the single oscillator Wemple Di-Domenico model. 相似文献
4.
Rohde S Gochfeld DJ Ankisetty S Avula B Schupp PJ Slattery M 《Journal of chemical ecology》2012,38(5):463-475
Chemical diversity represents a measure of selective pressures acting on genotypic variability. In order to understand patterns of chemical ecology and biodiversity in the environment, it is necessary to enhance our knowledge of chemical diversity within and among species. Many sponges produce variable levels of secondary metabolites in response to diverse biotic and abiotic environmental factors. This study evaluated intra-specific variability in secondary metabolites in the common Indo-Pacific sponge Stylissa massa over various geographic scales, from local to ocean basin. Several major metabolites were quantified in extracts from sponges collected in American Samoa, Pohnpei, Saipan, and at several sites and depths in Guam. Concentrations of several of these metabolites varied geographically across the Pacific basin, with American Samoa and Pohnpei exhibiting the greatest differences, and Guam and Saipan more similar to each other. There were also significant differences in concentrations among different sites and depths within Guam. The crude extract of S. massa exhibited feeding deterrence against the omnivorous pufferfish Canthigaster solandri at natural concentrations, however, none of the isolated compounds was deterrent at the maximum natural concentrations observed, nor were mixtures of these compounds, thus emphasizing the need for bioassay-guided isolation to characterize specific chemical defenses. Antibacterial activity against a panel of ecologically relevant pathogens was minimal. Depth transplants, predator exclusion, and UV protection experiments were performed, but although temporal variability in compound concentrations was observed, there was no evidence that secondary metabolite concentration in S. massa was induced by any of these factors. Although the reasons behind the variability observed in the chemical constituents of S. massa are still in question, all sponges are not created equal from a chemical standpoint, and these studies provide further insights into patterns of chemical diversity within S. massa. 相似文献
5.
Avula Sreenath Gurumurthy Ramachandran James H. Vincent 《Aerosol science and technology》2013,47(3):767-778
This article summarizes the results of an extensive experimental study of sampling losses in thin-walled probes at various values of velocity ratio R and the probe orientation with respect to the freestream. The purpose of this study was to gain insights into the complex interaction of various parameters that influence sampling losses and the consequent effect on the overall sampling efficiency. A 0.635 cm diameter sharp-edged tube was mounted in a small wind tunnel where the freestream velocity could be varied over a wide range of values. Polydispersed spherical glass beads were used as the test aerosol. The number concentration and the particle size distribution were measured using the aerodynamic particle sizer (APS 3310). The sampling efficiency was determined as a function of orientation for a range of particle sizes (or Stokes number). By using an existing model to predict the aspiration efficiency for thin-walled probes, the sampling losses could be isolated from the sampling efficiency. In this manner a new empirical model was developed to predict the losses as a complex function of Stokes number, sampler orientation, and velocity ratio. The losses appear to be influenced by particle inertia, impaction, gravitational settling in the boundary layer developing inside the thin-walled probe, and vena contracta or flow recirculation loss near the entry. It was evident from the results that these losses are strongly influenced by the Stokes number and sampler orientation. The losses also increased strongly with increasing value of velocity ratio for all orientations. 相似文献
6.
Inhibition of H2O2-induced apoptosis of lymphocytes by calorie restriction during aging 总被引:1,自引:0,他引:1
Calorie restriction (CR) is known to delay the aging process in rodents and is postulated to act by decreasing free radical generation and increasing antioxidant enzyme activity. The present study was designed to investigate the effect of CR and age on oxidative stress-induced apoptosis and associated changes in the levels of TNF-alpha, and Bcl-2 in splenic T lymphocytes. Ad libitum (AL)- or CR-fed C57BL/6J mice were sacrificed either at 6 (young) or 18 (old) months and splenic lymphocytes were incubated with or without 25 micro M H2O2 to induce apoptosis. Apoptosis increased with age in cells of AL-fed mice incubated with H2O2. CR prevented this rise in apoptosis in total splenic lymphocytes and in CD4(+) and CD8(+) T lymphocyte subsets either with or without H2O2. Free radicals increased and mitochondrial membrane potential decreased in aged mice. CR prevented these changes and also prevented the age-associated increase in TNF-alpha and loss of Bcl-2 in total splenic lymphocytes and in CD4(+) and CD8(+) lymphocyte subsets. In summary, lymphocytes in aged AL-fed mice were much more susceptible to oxidative stress-induced apoptosis whereas CR normalized apoptosis by preventing the increase in TNF-alpha and the decrease in Bcl-2 associated with aging. 相似文献
7.
A novel approach to clustering for image segmentation and a new object-based image retrieval method are proposed. The clustering is achieved using the Fisher discriminant as an objective function. The objective function is improved by adding a spatial constraint that encourages neighboring pixels to take on the same class label. A six-dimensional feature vector is used for clustering by way of the combination of color and busyness features for each pixel. After clustering, the dominant segments in each class are chosen based on area and used to extract features for image retrieval. The color content is represented using a histogram, and Haar wavelets are used to represent the texture feature of each segment. The image retrieval is segment-based; the user can select a query segment to perform the retrieval and assign weights to the image features. The distance between two images is calculated using the distance between features of the constituent segments. Each image is ranked based on this distance with respect to the query image segment. The algorithm is applied to a pilot database of natural images and is shown to improve upon the conventional classification and retrieval methods. The proposed segmentation leads to a higher number of relevant images retrieved, 83.5% on average compared to 72.8 and 68.7% for the k-means clustering and the global retrieval methods, respectively. 相似文献
8.
Damodaram R. Stephens K.T. Bishop W.S. Brackett P.O. Farkouh S.C. Chatterjee A. 《IEEE network》1994,8(6):48-54
The North Carolina Information Highway (NCIH) will support many applications, including distance learning, LAN interconnection, video conferencing, law enforcement, and health care. Initially, the NCIH is supporting distance learning and local area network (LAN) interconnection applications for the North Carolina State Government. The operations plan for the NCIH was driven by end-user service requirements, network operator requirements, and the network architecture. The NCIH is a multi-vendor, multi-carrier ATM network offering a 155-Mb/s OC-3c SONET/ATM customer access interface to support many applications. BellSouth, along with Bellcore, Fujitsu, NTI, and other carriers, has developed and implemented an operations plan for managing the NCIH 相似文献
9.
The authors investigate error detection and correction options for data services in the broadband integrated services digital network (B-ISDN). They discuss and analyze different options for error detection and correction by considering the various alternatives ranging from no error protection to only error detection. Based on the analysis and results presented, a per-cell cyclic redundancy check (CRC) has been adopted in the adaptation layer for all data services. The authors focus on the ATM (asynchronous transfer mode) adaptation layer (AAL) error protection alternatives available within the framework of a per-cell CRC. The ATM cell header and AAL fields are described. A 4 bit cell sequence number for detecting cell misordering is analyzed. Based on the analysis, it is concluded that the 4 bit sequence number provides a powerful capability for detection of cell misordering 相似文献
10.
Mayeli P. Contreras Ramesh Y. Avula Rakesh K. Singh 《Food and Bioprocess Technology》2010,3(4):629-635
The effect of nano zinc (ZnO) particles in surface enhancement of attenuated total reflection–Fourier transform mid-infrared
spectroscopy (ATR–FTIR) has been studied in butter and spread. Due to the health implications associated with consumption
of trans fats, the studies also included the determination of band corresponding to trans fats of butter/spread in the nano-zinc-treated samples. The FTIR spectra of nano-zinc-treated butter showed enhancement of
bands related to (―C―O, ―CH2―) at wave number 1,238 cm−1 and (O―C―C) band of esters at wave number 1,100 cm−1. Shifting in wave number to 1,150 cm−1 and reduction in its peak intensity was observed with the band corresponding to 1,162 cm−1 (―C―O stretch). Reduction in peak intensity of the bands at about 2,915 and 2,850 cm−1 (C―H groups) was also observed. In the case of spread, nano zinc reduced the peak intensities of FTIR bands at 2,915 cm−1, 2,850 cm−1 (―C―H― (CH2) stretches), 1,746 cm−1 (―C═O ester), 1,465 cm−1 (―C―H (CH2, CH3)), 1,375 cm−1 (―C―H (CH3)) and 1,156 cm−1 (C―O, ―CH2). Trans fats band corresponding to ═C―H stretch (trans bonds, 966 cm−1), was observed in pure butter and spread. Trans fatty acids in butter and spread were quantified with the aid of calibration/validation standards using trielaidin and triolein
and by using partial least squares regression analysis. However, the band at 966 cm−1 was hindered in Zn-treated butter and reduced in Zn-treated spread. 相似文献