Curcumin ((1E,6E)-1,7-Bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione), the yellow biphenolic pigment isolated from turmeric (Curcuma longa), has various medicinal benefits through ...antioxidation, anti-inflammation, cardiovascular protection, immunomodulation, enhancing of the apoptotic process, and antiangiogenic property. We explored the effects of curcumin in vitro (10−5 M to 10−8 M) and in vivo (340 and 170 mg/kg b.w., oral) on Na+/K+ ATPase (NKA), Na+/H+ exchanger (NHE) activity, and membrane lipid hydroperoxides (ROOH) in control and experimental oxidative stress erythrocytes of Wistar rats. As a result, we found that curcumin potently modulated the membrane transporters activity with protecting membrane lipids against hydro-peroxidation in control as well as oxidatively challenged erythrocytes evidenced by stimulation of NKA, downregulation of NHE, and reduction of ROOH in the membrane. The observed results corroborate membrane transporters activity with susceptibility of erythrocyte membrane towards oxidative damage. Results explain the protective mechanism of curcumin against oxidative stress mediated impairment in ions-transporters activity and health beneficial effects.
Solid Oxide Fuel Cells: Technology Status Singh, Prabhakar; Minh, Nguyen Q.
International journal of applied ceramic technology,
January 2004, Volume:
1, Issue:
1
Journal Article
Peer reviewed
In its most common configuration, a solid oxide fuel cell (SOFC) uses an oxygen‐ion conducting ceramic electrolyte membrane, perovskite cathode, and nickel cermet anode electrode. Cells operate in ...the 600–1000°C temperature range and utilize metallic or ceramic current collectors for cell‐to‐cell interconnection. Recent developments in engineered electrode architectures, component materials chemistry, cell and stack designs, and fabrication processes have led to significant improvements in the electrical performance and performance stability as well as reduction in the operating temperature of such cells. Large kW‐size power‐generation systems have been designed and field demonstrated. This paper reviews the status of SOFC power‐generation systems with emphasis on cell and stack component materials, electrode reactions, materials reactions, and corrosion processes.
Cancer is the utmost common disease-causing death worldwide, characterized by uncontrollable cell division with the potential of metastasis. Overexpression of the Inhibitors of Apoptosis proteins ...(IAPs) and autophagy correlates with tumorigenesis, therapeutic resistance, and reoccurrence after anticancer therapies. This study illuminates the role and efficacy of smac mimetic compound BV6 alone and in co-treatment with death ligands such as TRAIL and TNFα in the regulation of cell death mechanisms, i.e., apoptosis and autophagy. In this study, MTT assays, wound healing assays, and cellular and nuclear morphological studies were done. DAPI staining, AO/EtBr staining and AnnexinV/PI FACS was done to study the apoptosis. The expression of IAPs and autophagy biomarkers was analyzed using Real time-PCR and western blotting. Meanwhile, TEM demonstrated autophagy and cellular autophagic vacuoles in response to the BV6. The result shows a promising anti-cancer effect of BV6 alone as well as in combinational treatment with TRAIL and TNFα, compared to the lone treatment of TRAIL and TNFα in both breast cancer cell lines. The smac mimetic compound might provide an alternative combinational therapy with conventional anticancer therapies to tackle their inefficiency at the advanced stage of cancer, cancer resistance, and reoccurrence. Also, IAPs and autophagic proteins could act as potent target molecules for the development of novel anti-cancer drugs in pathogenesis and the betterment of regimens for cancer.
We have investigated the structural and chemical stability of La0.8Sr0.2MnO3 (LSM)–8mol.% yttria stabilized zirconia (YSZ) composite. LSM and YSZ powders were mixed and sintered at 1400°C for 10h in ...controlled atmosphere (PO2=0.21 to 10−6atm). The unit cell volume of LSM increases during exposure to reduced oxygen partial pressure while it remains unchanged for YSZ. During reduction in the oxygen partial pressure from 0.21atm to 10−6atm, the solubility of manganese in YSZ increases from ∼10at.% to ∼15at.%. Lower oxygen partial pressure also results in the grain growth and formation of La2Zr2O7 and MnOx (Mn3O4) compounds lowering the stability of the LSM–YSZ composite. On subsequent sintering in 0.21atm PO2, the La2Zr2O7 and MnOx compounds tend to disappear indicating the reversibility of the interaction. The reversibility of LSM–YSZ reaction has been independently confirmed using La2Zr2O7 and MnOx.
This paper describes Pd(II)‐catalyzed picolinamide‐directed intermolecular arylation and benzylation of remote δ−C(sp2)−H bond (C(2) position) of the aryl ring in tyrosine derivatives and expansion ...of the library of unnatural tyrosine. Various racemic and enantiopure bis C(2) (ortho C−H) arylated and benzylated tyrosine derivatives were assembled in good yields. Removal of the picolinoyl moiety after the C(2)−H arylation and assembling of tyrosine‐based peptides using C(2)−H arylated tyrosines were shown. Tyrosine derivatives and biaryl amino acids are vital scaffolds in medicinal chemistry. Correspondingly, this work is a contribution towards the expansion of the unnatural tyrosine library with biaryl‐ or terphenyl and diarylmethane‐based tyrosine scaffolds.
The Pd(II)‐catalyzed picolinamide‐directed arylation and benzylation at the remote δ−C(sp2)−H and C(2) position of the aryl ring in tyrosines and the assembling of C(2) arylated and benzylated tyrosines are reported. Expansion of the substrate scope in site‐selective remote δ−C(sp2)−H functionalization and synthesis of biaryl‐, terphenyl‐ and diarylmethane‐based unnatural tyrosines and peptides are shown.
Yttria-stabilized zirconia (YSZ) is a common solid electrolyte for solid oxide fuel cells (SOFCs) because of its high electrical conductivity and high ionic transference number in both oxidizing and ...reducing atmospheres. Samarium doped ceria (SDC) has also been considered as an alternative electrolyte material to YSZ for intermediate temperature SOFC because of its high conductivity at relatively low temperatures. Due to improved ionic conductivity of YSZ at high temperature (~ 800°C) and good conductivity of SDC in the intermediate temperature range (600–800°C), the electrical properties of YSZ-SDC composites were investigated. Composites of YSZ and SDC with weight ratio 9.5:0.5, 9:1 and 8.5:1.5 were synthesized via glycine-nitrate route. XRD pattern of the systems revealed the formation of composite phases. Biphasic electrolyte microstructures were observed, in which SDC grains are dispersed in YSZ matrix. Relative density of the compositions was found to be more than 92% to the theoretical density. It was observed that the interface provides a channel for ionic transport, leading to a notable ionic conductivity. With increase in SDC weight ratio the electrical conductivity was found to increase. For weight ratio 8.5:1.5 the electrical conductivity was found to be greater than that of YSZ in the temperature range 400–700°C. Further, for weight ratio more than 8.5:1.5, conductivity was found to decreases due to the formation of a few other insulating impurity phases. The electrode polarisation was also found to reduce significantly with SDC in the composite electrolyte system. Thus, such composite system may be useful for improving the ionic conductivity of the composite electrolytes.
Cardiovascular diseases (CVDs) remain a major global health burden, and emerging evidence suggests that the gut microbiome plays a pivotal role in their pathogenesis and progression. This review ...paper aims to comprehensively analyze the intricate interplay between the gut microbiome and cardiovascular health. An extensive examination of existing literature explores how gut microbial composition and function influence CVD risk factors, such as inflammation, lipid metabolism, and blood pressure regulation. Additionally, we delve into the impact of dietary patterns, medications, and lifestyle factors on shaping the gut microbiota and how these changes can exacerbate or ameliorate cardiovascular outcomes. We also discuss COVID-19, gut microbiome and CVDs. Furthermore, we discuss the potential of gut microbiome-targeted interventions as promising avenues for preventing and managing CVDs. By consolidating the current knowledge, this review aims to shed light on the intricate link between the gut microbiome and cardiovascular diseases and highlights the potential for novel therapeutic strategies to combat this significant public health challenge.
•The review focuses on the significant role of gut microbes in the pathogenesis and progression of CVDs.•The review highlights the microbial influence on key drivers of cardiovascular health.•The review explores the effects of dietary patterns, medications, and lifestyle choices on shaping the gut microbiota.•The review also addresses the intersection of COVID-19 with the gut microbiome and CVDs.•The review highlights the potential of gut microbial interventions as promising strategies for preventing and managing CVDs.
Abstract In this paper, a modified L-strip fed patch antenna is theoretically analyzed for wideband applications. Dual U-shaped slots are incorporated in the radiating patch and a maximum bandwidth ...of 16.93% (2.65 GHz to 3.14 GHz) is achieved. Further, when two parasitic elements are used, antenna bandwidth improves up to 25.89% (2.90 GHz to 3.77 GHz). The maximum gain of dual U-slotted patch and with parasitic elements is 8.23 dBi and 8.46 dBi respectively. Antenna parameters are calculated by CST Microwave studio and equivalent circuit model theory is presented. The proposed antenna is fabricated and the measured results compare well with the theoretical as well as simulated results.
The increased lead (Pb) content in the environment has an impact on all living beings, including plant growth and quality. The present study aims to investigate the protective roles of zinc (Zn)- and ...iron (Fe)- nanoparticles (NPs) in alleviating stress symptoms caused by lead (Pb) exposure in Basella alba seedlings. For this purpose, 15 different treatment combinations of seed priming with two NPs at 0 and 200 mg L−1, and five Pb levels (0, 4, 8, 15, 20 mM) were chosen. Pb stress (20 mM) was found to reduce seed germination by 72.8% and seedling growth, particularly root length, by 92% when compared to the control. Under different Pb concentrations, seed priming with ZnNPs (200 mg L−1) and FeNPs (200 mg L−1) increased seed germination by 34.7% and 54.9%, respectively, and root length by 152.9% and 252.9%, respectively. In 20 mM Pb stress, NPs primed seedling showed decrease in Pb content by 33.7% with ZnNPs and 32.6% with FeNPs. Increased Pb stress resulted in increased reactive oxygen species (ROS) generation (H2O2) and lipid peroxidation (MDA) compared to non-Pb stressed seedlings. However, increased antioxidants in the NPs treatments such as SOD, CAT, POD and proline content, scavenged these ROS. Considering all the parameters under study, priming alleviated Pb stress in the following order: FeNPs > ZnNPs > hydropriming > control. To summarise, seed priming with Zn- and Fe-NPs has the potential to alleviate Pb toxicity via reduced Pb uptake, ROS generation and lipid peroxidation as well as increased proline content and activation of antioxidant enzymatic system.
Plasma membrane redox system (PMRS) is an electron transport chain system ubiquitously present throughout all cell types. It transfers electron from intracellular substrates to extracellular ...acceptors for regulation of redox status. Curcumin, isolated from Curcuma longa, has modulatory effects on cellular physiology due to its membrane interaction ability and antioxidant potential. The present study investigates the effect of curcumin on PMRS activity of erythrocytes isolated from Wistar rats in vitro and in vivo and validated through an in silico docking simulation study using Molegro Virtual Docker (MVD). Effects of curcumin were also evaluated on level of glutathione (GSH) and the oxidant potential of plasma measured in terms of plasma ferric equivalent oxidative potentials (PFEOP). Results show that curcumin significantly ( p < 0.01 ) downregulated the PMRS activity in a dose-dependent manner. Molecular docking results suggest that curcumin interacts with amino acids at the active site cavity of cytochrome b 5 reductase, a key constituent of PMRS. Curcumin also increased the GSH level in erythrocytes and plasma while simultaneously decreasing the oxidant potential (PFEOP) of plasma. Altered PMRS activity and redox status are associated with the pathophysiology of several health complications including aging and diabetes; hence, the above finding may explain part of the role of curcumin in health beneficial effects.
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