To understand the post-transcriptional molecular mechanisms attributing to oleaginousness in microalgae challenged with nitrogen starvation (N-starvation), the longitudinal proteome dynamics of ...Chlorella sp. FC2 IITG was investigated using multipronged quantitative proteomics and multiple reaction monitoring assays. Physiological data suggested a remarkably enhanced lipid accumulation with concomitant reduction in carbon flux towards carbohydrate, protein and chlorophyll biosynthesis. The proteomics-based investigations identified the down-regulation of enzymes involved in chlorophyll biosynthesis (porphobilinogen deaminase) and photosynthetic carbon fixation (sedoheptulose-1,7 bisphosphate and phosphoribulokinase). Profound up-regulation of hydroxyacyl-ACP dehydrogenase and enoyl-ACP reductase ascertained lipid accumulation. The carbon skeletons to be integrated into lipid precursors were regenerated by glycolysis, β-oxidation and TCA cycle. The enhanced expression of glycolysis and pentose phosphate pathway enzymes indicates heightened energy needs of FC2 cells for the sustenance of N-starvation. FC2 cells strategically reserved nitrogen by incorporating it into the TCA-cycle intermediates to form amino acids; particularly the enzymes involved in the biosynthesis of glutamate, aspartate and arginine were up-regulated. Regulation of arginine, superoxide dismutase, thioredoxin-peroxiredoxin, lipocalin, serine-hydroxymethyltransferase, cysteine synthase, and octanoyltransferase play a critical role in maintaining cellular homeostasis during N-starvation. These findings may provide a rationale for genetic engineering of microalgae, which may enable synchronized biomass and lipid synthesis.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
We report on the synthesis of ZnO quantum dots (QDs) rich in oxygen vacancies by inducing an oxygen deficient environment. The precise tunability of particle size is achieved by counter ion capping ...of the precursor used for synthesis. The prepared QDs show size tunable visible emission with high quantum yield.
A new synthesis method is developed for preparation of mesoporous strontium hydroxyapatite (SrHAp) nanorods using CEM Discover microwave synthesizer. Nanorods preparation with surfactants SrHAp(+) ...and without surfactants SrHAp(−) were successfully achieved at 160 °C temperature and 15 min of hold time. Particle sizes with standard deviation were found to be 67 ± 18 and 69 ± 24 nm respectively. Mesoporous nanorods were thoroughly characterized using different methods, such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field-emission gun transmission electron microscopy (FEG-TEM), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) surface area and porosity measurement. It was observed that use of trisodium citrate and CTAB resulted in quite agglomerated particles, whereas nanorods synthesized without citrate and CTAB were well dispersed. Cell toxicity of both these materials synthesized was tested in MCF-7 and Zr-75 cell lines using MTT assay. SrHAp nanorods concentration up to 0.25 mg/ml was non-toxic at 48 hours (h) time point in both the cell lines. As SrHAp(−) were found to serve better in terms of cytotoxicity, they were chosen for doxorubicin (Dox) loading, pH depended release and cell uptake study. The successful loading of Dox was ascertained by UV-Visible and FTIR spectroscopy. Entrapment efficiency of Dox in SrHAp nanoparticles was found to be 83.71%, and loading capacity was 0.017 μg Dox per μg SrHAp nanoparticles. Rapid release was observed in the initial hours followed by slow release. Even until 31 days, only 27 and 32% drug was released at pH 7.4 and pH 4.5 respectively, which shows controlled release behavior. Further, cellular uptake of Dox-loaded nanoparticles at different time points was studied in the two breast cancer cell lines by fluorescence imaging. These nanoparticles were found to internalize within both these cells after 3 h of incubation and continued further until 24 h. Overall, high Dox loading efficacy, sustained release behavior, and cell uptake potential render SrHAp nanoparticles to give promising results when applied in vivo and emerge as a robust drug carrier towards solving purpose of slow and prolonged drug release.
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Gliomas are one of the most aggressive primary brain tumors arising from neural progenitor cells. Delayed diagnosis, invasive biopsy, and diagnostic challenges stems the need for specific, ...minimally-invasive, and early diagnostic biomarkers. Tumor-associated (TA) autoantibodies are measurable in the biofluids long before the onset of the symptoms, suggesting their role in early diagnosis and clinical management of the patients. In the current study, cerebrospinal fluid (CSF) samples from patients with low-grade glioma (LGG) and the
(GBM) that characterizes advanced disease were compared with healthy control samples to identify putative TA autoantibodies, using protein microarrays. The CSF samples from LGGs (n = 10), GBM (n = 7) were compared with the control CSF samples (n = 6). Proteins showing significant antigenic response were cross-verified. Proteins NOL4 (a cancer-testis antigen) and KALRN showed an antigenic response in the CSF of GBM patients, whereas, UTP4 and CCDC28A showed an antigenic response in low grade gliomas when compared with the control samples. TA autoantibodies identified in this study from the CSF of the patients could supplement current screening modalities. Further validation of these TA autoantibodies on a larger clinical cohort could provide cues towards relevance of these proteins in early diagnosis of the disease.
Red emissive carbon dots from sucrose (SCD) were synthesized using a facile, isolation-free, one-pot method via microwave pyrolysis. Various passivation agents were used along with sucrose, and a ...relative change in the chemical and optical properties of the carbon dots was investigated. A detailed systematic study of the effect of various passivations, different solvents, pHs, and temperatures on optical properties was carried out. The influence of excitation wavelength and passivation on photoluminescence (PL) is discussed considering the functional groups associated with the passivating agents. The effect of different solvents on dispersibility and PL behavior has been understood in terms of the dielectric properties of the solvents. The decrease in PL intensity of SCD from pH 3 to 11 facilitates pH sensing. The PL of SCD was found to be essentially stable between the temperature range of 20 and 80 °C. Additionally, the effects of physicochemical properties with respect to passivation, such as charge and surface chemistry in determining the cellular uptake and cytotoxicity, are also addressed. Aside from sensors, the potential of SCDs as bioimaging agents has also been studied for mammalian cells. Moreover, SCD exhibits excellent PL stability investigated under different storage conditions for 15 days.
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IJS, KILJ, NUK, PNG, UL, UM
In sunscreens, ZnO nanoparticles (NPs) are used as inorganic UV filter which have a prominent band edge emission in the UVA region (~385 nm). When applied to biological surface, this highly ...penetrating UVA emission from ZnO NPs would enhance the generation of reactive oxygen species resulting in oxidative stress. Therefore, the elimination of this harmful UVA emission from ZnO NPs are much sought after for the development of safer sunscreens. In this paper we introduce the use of defect-rich ZnO (D-ZnO) quantum dots (QDs) as a multifunctional active ingredient in sunscreen/cosmetic application. These D-ZnO QDs make use of their defect energy levels to emit in visible region by bypassing their harmful band edge emission at UVA region. The D-ZnO QDs also showed prominent visible luminescence which matches well with the autofluorescence of in vivo human skin. Hence, this visible luminescence could be useful for camouflaging, thereby enabling its potential as a biologically safe active ingredient for both cosmetic and UV screening applications.
Nanoparticles of Ni0.5Co0.2Zn0.3Fe2O4 were prepared using the sol‐gel combustion route. The nanoparticles were characterised by x‐ray diffraction to confirm single‐phase formation in a cubic spinel ...structure. Micro‐ and nanostructural analyses were carried out using field emission‐scanning electron microscopy and field emission‐transmission electron microscopy, respectively. A planetary ball milling technique was used to grind the powder into nanoparticles; the average particle size was 64 nm. Energy‐dispersive X‐ray spectroscopy was used to determine the atomic composition of the sample. Radio‐frequency characteristics were recorded for dielectric measurement in a frequency range of 1 Hz to 15 MHz using a broadband dielectric spectrometer. Terahertz (THz) time‐domain spectroscopy was performed to study THz‐optical parameters such as refractive index, dielectric constant, and conductivity at room temperature in a frequency range of 0.3−2.2 THz using an indigenously developed THz time‐domain spectroscopy setup. The magnetic properties of the sample were studied using a SQUID vibrating sample magnetometer under an applied magnetic field of ±10 kOe. An examination of M‐H loops revealed that the saturation magnetization (Ms), remanent magnetization (Mr) and coercivity (Hc) increased with an increase in temperature from 300 to 50 K.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
In Plasmodium vivax malaria, mechanisms that trigger transition from uncomplicated to fatal severe infections are obscure. In this multi-disciplinary study we have performed a comprehensive analysis ...of clinicopathological parameters and serum proteome profiles of vivax malaria patients with different severity levels of infection to investigate pathogenesis of severe malaria and identify surrogate markers of severity. Clinicopathological analysis and proteomics profiling has provided evidences for the modulation of diverse physiological pathways including oxidative stress, cytoskeletal regulation, lipid metabolism and complement cascades in severe malaria. Strikingly, unlike severe falciparum malaria the blood coagulation cascade was not found to be affected adversely in acute P. vivax infection. To the best of our knowledge, this is the first comprehensive proteomics study, which identified some possible cues for severe P. vivax infection. Our results suggest that Superoxide dismutase, Vitronectin, Titin, Apolipoprotein E, Serum amyloid A, and Haptoglobin are potential predictive markers for malaria severity.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
We present detailed studies on M-type barium ferrite (BaFe12O19, BaM) synthesized by the sol–gel combustion method that is calcined at 1000 °C, 1100 °C, and 1200 °C. In addition to the structural ...properties, we present the THz optical dielectric constant and conductivity response of this system as a function of calcination temperature. From x-ray diffraction (XRD) studies, a single-phase of the hexagonal structure is established, and the crystallite size (Dhkl) was calculated to be in the range of 26 nm–28.54 nm. The XRD patterns were analyzed to evaluate lattice parameters (a, c, V) and x-ray density (ρx). Home built terahertz time-domain spectroscopy was performed to investigate the complex refractive index (n̂s) of the samples at room temperature in a frequency range of 0.2 THz–1.2 THz. The complex dielectric constant (ε̂s) and conductivity (σ̂s) as a function of calcination temperature were deduced using THz spectroscopy data. The complex dielectric constant and conductivity of BaM were determined for the calcination temperatures of 1000 °C, 1100 °C, and 1200 °C.
Purpose
Gliomas are one of the most aggressive and lethal brain tumors arising from neoplastic transformation of astrocytes and oligodendrocytes. A comprehensive quantitative analysis of proteome ...level differences in cerebrospinal fluid (CSF) across different grades of gliomas for a better understanding of glioma pathobiology is carried out.
Experimental design
Glioma patients are diagnosed by radiology and histochemistry‐based analyses. Differential proteomic analysis of high (n = 12) and low (n = 8) grade gliomas, and control (n = 3) samples is performed by using two complementary quantitative proteomic approaches; 2D‐DIGE and iTRAQ. Further, comparative analysis of three IDH wild‐type and five IDH mutants is performed to identify the proteome level differences between these two sub‐classes.
Results
Level of several proteins including haptoglobin, transthyretin, osteopontin, vitronectin, complement factor H and different classes of immunoglobulins are found to be considerably increased in CSF of higher grades of gliomas. Subsequent bioinformatics analysis indicated that many of the dysregulated CSF proteins are associated with metabolism of lipids and lipoproteins, complement and coagulation cascades and extracellular matrix remodeling in gliomas. Intriguingly, CSF of glioma patients with IDH mutations exhibite increased levels of multiple proteins involved in response to oxidative stress.
Conclusion and clinical relevance
To the best of our knowledge, this is the foremost proteome level investigation describing comprehensive proteome profiles of different grades of gliomas using proximal fluid (CSF); and thereby providing insights into disease pathobiology, which aided in identification of grade and sub‐type specific alterations. Moreover, if validated in larger clinical cohorts, a panel of differentially abundant CSF proteins may serve as potential disease monitoring and prognostic markers for gliomas.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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