247 research outputs found
Non-invasive oral cancer detection from saliva using zinc oxide-reduced graphene oxide nanocomposite based bioelectrode
Multifunctional materials with excellent biocompatibility and electron-transport properties are critical for the pursuit of point-of-care biosensing devices. The authors report the synthesis of zinc oxide-reduced graphene oxide (ZnO-rGO) nanocomposite for the fabrication of an electrochemical immunosensing test-bed for noninvasive onsite detection of oral cancer biomarker (interleukin-8, IL8). The immunosensor showed successful detection of IL8 at low concentration ranges, i.e., 100 fg/mL-5 ng/mL with a sensitivity of 12.46 +/- 0.82 mu A mL/ng and a detection limit of 51.53 +/- 0.43 pg/mL. These results have been validated through in vitro investigations using real saliva samples spiked with IL8
Readily available sources of long-chain omega-3 oils: Is farmed australian seafood a better source of the good oil than wild-caught seafood?
Seafood consumption enhances intake of omega-3 long-chain (≥C20) polyunsaturated fatty acids (termed LC omega-3 oils). Humans biosynthesize only small amounts of LC-omega-3, so they are considered semi-essential nutrients in our diet. Concern has been raised that farmed fish now contain lower LC omega-3 content than wild-harvested seafood due to the use of oil blending in diets fed to farmed fish. However, we observed that two major Australian farmed finfish species, Atlantic salmon (Salmo salar) and barramundi (Lates calcifer), have higher oil and LC omega-3 content than the same or other species from the wild, and remain an excellent means to achieve substantial intake of LC omega-3 oils. Notwithstanding, LC omega-3 oil content has decreased in these two farmed species, due largely to replacing dietary fish oil with poultry oil. For Atlantic salmon, LC omega-3 content decreased ~30%-50% between 2002 and 2013, and the omega-3/omega-6 ratio also decreased (>5:1 to <1:1). Australian consumers increasingly seek their LC omega-3 from supplements, therefore a range of supplement products were compared. The development and future application of oilseeds containing LC omega-3 oils and their incorporation in aquafeeds would allow these health-benefitting oils to be maximized in farmed Australian seafood. Such advances can assist with preventative health care, fisheries management, aquaculture nutrition, an innovative feed/food industry and ultimately towards improved consumer health
Uncertainty Measurements in Chemically Synthesized Stable Uniform Sized Gold Nanoparticles for TEM/HRTEM Calibration
83-91The accuracy of an electron microscope depends on the magnification and resolution of the microscope. Hence in order to achieve high accuracy measurement results from the electron microscopic examination, a standard specimen is required to calibrate the transmission electron microscope (TEM). In the present work, gold nanoparticles of uniform size with narrow particle size distribution were synthesized with an aim to use them as reference material (RM) for TEM/high resolution TEM calibration and then release them in market as Bhartiya Nideshak Dravya (BND). As synthesized gold nanoparticles at 20 ± 2 °C temperature and 45± 5% relative humidityand the standard sample were characterized by using HRTEM, model: FEI-Tecnai F30 G2 STWIN at suitable magnification and areas. Both images exhibit spherical shaped nanoparticles with size varying in the range from (15.35-20.15 nm) and (5.10 -7.70 nm) respectively. Stability in particles size of the chemically synthesized gold nanoparticles was studied for a period of one year time span using UV-Visible spectrometer. TEM/HRTEM measurements were carried out in automated mode under similar experimental and environmental conditions at different magnifications to get accurate particle size. Overall uncertainty is estimated in small and big size particles as per standard GUM document guidelines
Agrobacterium-mediated transformation of safflower and the efficient recovery of transgenic plants via grafting
<p>Abstract</p> <p>Background</p> <p>Safflower <it>(Carthamus tinctorius L.) </it>is a difficult crop to genetically transform being susceptible to hyperhydration and poor <it>in vitro </it>root formation. In addition to traditional uses safflower has recently emerged as a broadacre platform for the production of transgenic products including modified oils and pharmaceutically active proteins. Despite commercial activities based on the genetic modification of safflower, there is no method available in the public domain describing the transformation of safflower that generates transformed T<sub>1 </sub>progeny.</p> <p>Results</p> <p>An efficient and reproducible protocol has been developed with a transformation efficiency of 4.8% and 3.1% for S-317 (high oleic acid content) and WT (high linoleic acid content) genotypes respectively. An improved safflower transformation T-DNA vector was developed, including a secreted <it>GFP </it>to allow non-destructive assessment of transgenic shoots. Hyperhydration and necrosis of <it>Agrobacterium</it>-infected cotyledons was effectively controlled by using iota-carrageenan, L-cysteine and ascorbic acid. To overcome poor <it>in vitro </it>root formation for the first time a grafting method was developed for safflower in which ~50% of transgenic shoots develop into mature plants bearing viable transgenic T<sub>1 </sub>seed. The integration and expression of secreted <it>GFP </it>and hygromycin genes were confirmed by PCR, Southern and Western blot analysis. Southern blot analysis in nine independent lines indicated that 1-7 transgenes were inserted per line and T<sub>1 </sub>progeny displayed Mendelian inheritance.</p> <p>Conclusions</p> <p>This protocol demonstrates significant improvements in both the efficiency and ease of use over existing safflower transformation protocols. This is the first complete method of genetic transformation of safflower that generates stably-transformed plants and progeny, allowing this crop to benefit from modern molecular applications.</p
Dual Wavelength based Approach with Partial Least Square Regression for the Prediction of Glucose Concentration
Diabetes mellitus is a group of metabolic disorder characterized by high blood sugar levels. Monitoring of blood glucose levels at regular intervals plays a crucial role in the management of diabetes. The non-invasive real-time monitoring of glucose using near-infrared (NIR), Raman, acoustic and bio-impedance techniques have an edge over available invasive techniques but suffers from low Signal to Noise ratio (S/N) and other interferences. In the present work, we have attempted to improve S/N for the efficient detection of feeble signals corresponding to the physiological glucose concentrations. Investigations were carried out in the NIR region particularly from 800-1400 nm for the identification of the unique absorption features of glucose using UV-Vis NIR spectrophotometer with different ranges of glucose concentrations including 5 g/dl- 45 g/dl, 1400 mg/dl -2500 mg/dl, 35 mg/dl-650 mg/dl . Savitzky Golay (SG) pre-processing filter was applied on the raw data for enhancing the S/N for better prediction of glucose concentrations. The absorption spectra of glucose revealed the presence of a peak at 960 nm. Therefore, considering the absorbance at 960 nm, provided an enhancement in the S/N ratio from 17 dB to 27 dB. Further, partial least square regression (PLSR), has been applied on SG filtered data for a better prediction of glucose concentration with a correlation coefficient ( R2) value of 0.99 and root mean square error of prediction (RMSE) of 2.29 mg/dl. Further, based on the NIR spectral data, we have developed a measurement technique using two LED sources of 950 nm and 860 nm, and a wide detector (700 - 1100 nm) which converts obtained optical signal into voltage. It has been observed that by considering dual wavelength detection points the prediction of glucose concentration is improved. Furthermore, with increase in the test glucose concentrations, the voltage signal decreased corresponding to the 950 nm LED. This is attributed to reduced signal intensities reaching the photodiode as a result of the increase in glucose absorption. Incorporating dual wavelengths for PLSR reduced the RMSE from 8.98 mg/dl to 6.49 mg/dl and also improved the R2 value from 0.97 to 0.99
Low-frequency dielectric processes in deformed helix ferroelectric liquid crystals
A low-frequency dielectric relaxation mode in deformed helix ferroelectric liquid crystal (DHFLC) has been observed at the interface of strongly rubbed substrates and DHFLC material which may find applications in low power consumption FLC devices. The surface-induced dielectric relaxation process at the interface of DHFLC and substrate is called the partially unwound helical mode (p-UHM) due to the unwinding of the helical structure at this interface. After investigation of the material under various parameters such as temperature, variation of the amplitude of probing ac voltage and dc bias voltage, the relaxation frequency of p-UHM is found to be shifted towards Goldstone mode and merged with it. The relaxation frequency of Goldstone mode is found to decrease, whereas the relaxation frequency of p-UHM process increases with the increase in temperature of DHFLC. Finally, both the modes merge and the resultant relaxation frequency is found to be lower than Goldstone mode in SmC* phase. It seems that phason mode and partial helical unwinding mode are coupled together due to dipole moment that is resulting in a new relaxation frequency. p-UHM process is significant for low-power displays and non-displays applications like a part of sensor where weak electric signal is required to be realized without pre-amplification
Bucky Tubes Induce Oxidative Stress Mediated Cell Death in Human Lung Cells
Unique physicochemical properties of carbon nanomaterials (CNMs) have opened a new era for therapeutics and diagnosis (known as theranostics) of various diseases. This exponential increase in application makes them important for toxicology studies. The present study was aimed at exploring the toxic potential of one of the CNMs, that is, bucky tubes (BTs), in human lung adenocarcinoma (A549) cell line. BTs were characterised by electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform spectroscopy (FTIR), and X-ray diffraction (XRD). Flow cytometric study showed a concentration and time dependent increase in intracellular internalization as well as reduction in cell viability upon exposure to BTs. However, a significant increase in intracellular reactive oxygen species (ROS) production was observed as evident by increased fluorescence intensity of 2',7' - dichlorofluorescein (DCF). BTs induced oxidative stress in cells as evident by depletion in glutathione with concomitant increase in lipid peroxidationwith increasing concentrations. Asignificant increase in micronucleus formation and apoptotic cell population and loss of mitochondrial membrane potential (MMP) as compared to control were observed. Moreover, in the present study, BTs were found to be mild toxic and it is encouraging to conclude that BTs having outer diameter in the range of 7-12 nm and length 0.5-10 mu m can be used for theranostics
Collective dielectric processes at the transition temperature of the Sm-C* and Sm-A* phase in a ferroelectric liquid crystal
An anomalous dielectric relaxation process, called the partially unwound helical mode (p-UHM), is a collective dielectric process apart from the well known Goldstone and soft mode process; it is studied in the smectic C* (Sm-C*) phase and at the transition temperature of the Sm-C*-Sm-A* phase in the ferroelectric liquid crystal (FLC) material. To avoid the surface effect, a thick cell of 40 mu m thickness was prepared with highly rubbed surfaces of the ITO substrates. It has been observed that the dielectric properties in Sm-C* and at the T-c temperature are dominated by the p-UHM process which is dependent on an applied oscillating field in the Sm-C* phase. The probing ac and dc bias field dependences of all these collective dielectric processes have been reported in the Sm-C* and Sm-A* phases of FLC materials
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