•CoFe2O4/(MWCNTs)x nano-composites were prepared using ultra-sonication method.•Toluene was used as dispersive medium for these nano-composites.•Significant enhancement in dielectric properties of ...these nano-composites was observed with increased MWCNTs contents.•Improved impedance spectroscopic properties were observed for these nano-composites.•These nano-composites can be promising candidates for high-performance energy storage materials.
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Cobalt ferrite ‘CoFe2O4’ (CF) nanoparticles were prepared by co-precipitation method and their nano-composites with Multi-Walled Carbon Nanotubes (MWCNTs) (i.e.; CF/(MWCNTs)x; x = 0–30 wt% were synthesized using ultra-sonication route. Toluene was used as dispersive medium for uniform dispersion of MWCNTs. These nano-composites were characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), dielectric and impedance measurements. Single phase FCC structures of these nano-composites were explored by XRD and the aggregation of CF nanoparticles on MWCNTs was seen by SEM. The dielectric and impedance measurements were carried out with the help of LCR meter. The dielectric parameters i.e.; dielectric constants, dielectric loss, and loss tangent were increased with augmented MWCNTs contents in comparison to pure CF nanoparticles. While, impedance measurements showed leaning behavior with increased MWCNTs contents. These enhanced dielectric properties of CF/(MWCNTs)x nano-composites can be subjugated in various energy storage devices.
Pyrrole is a heterocyclic ring template with multiple pharmacophores that provides a way for the generation of library of enormous lead molecules. Owing to its vast pharmacological profile, pyrrole ...and its analogues have drawn much attention of the researchers/chemists round the globe to be explored exhaustively for the benefit of mankind. This review focusses on recent advancements; pertaining to pyrrole scaffold, discussing various aspects of structure activity relationship and its bioactivities.
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•Pyrrole is a heterocyclic aromatic five membered multiple pharmacophoric template.•The name pyrrole came from the Greek word ‘pyrrols’ means fiery from the reaction.•Pyrroles exhibit lower basicity due to delocalization of lone pair of electrons of nitrogen atom in the pyrrole ring.•The NH and CH protons are moderately acidic and can be deprotonated with strong bases, showing its nucleophilic nature.
Radiative heat transfer (RHT) has a central role in entropy generation and energy transfer at length scales ranging from nanometres to light years
. The blackbody limit
, as established in Max ...Planck's theory of RHT, provides a convenient metric for quantifying rates of RHT because it represents the maximum possible rate of RHT between macroscopic objects in the far field-that is, at separations greater than Wien's wavelength
. Recent experimental work has verified the feasibility of overcoming the blackbody limit in the near field
, but heat-transfer rates exceeding the blackbody limit have not previously been demonstrated in the far field. Here we use custom-fabricated calorimetric nanostructures with embedded thermometers to show that RHT between planar membranes with sub-wavelength dimensions can exceed the blackbody limit in the far field by more than two orders of magnitude. The heat-transfer rates that we observe are in good agreement with calculations based on fluctuational electrodynamics. These findings may be directly relevant to various fields, such as energy conversion, atmospheric sciences and astrophysics, in which RHT is important.
The prerequisite for high-performance lithium-ion batteries (LIBs) is an electrode material that offers high electric conductivity, fast ion transport, and large surface area. Monodispersed cobalt ...ferrite (CoFe2O4) nanoparticles have been successfully assembled on the surface of multi-walled carbon nanotubes (MWCNTs) by an ultra-sonication assisted route at room temperature. The dispersion has been carried out through a dispersive media (i.e. Toluene) for the formation of (MWCNTs)x/CoFe2O4 nanohybrids. These (MWCNTs)x/CoFe2O4 nanohybrids exhibit excellent electrochemical performance at different current densities. As anode materials for LIBs, these (MWCNTs)x/CoFe2O4 nanohybrids deliver a high specific capacity of 1370 mAhg−1, which is much higher than CoFe2O4 (1060 mAhg−1) nanoparticles and superior cyclic stability (1015 mAhg−1) after 25 cycles at 0.2 C-rate. These MWCNTs serve as good electron conductors and volume buffers in improving the lithium performance of (MWCNTs)x/CoFe2O4 nanohybrids during the discharge and charge process. Furthermore, these nanohybrids have shown high rate capability (640 mAhg−1) at 2.0 A g-1 that returns to the initial capacity of 970 mAhg−1 at 0.1 A g-1 after 30 cycles with Columbic efficiency above 97%. This work offers an easy, large-scale, and low-cost route to produce high electrochemical performance anode materials for LIBs.
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•(MWCNTs)x/CoFe2O4 nanohybrids were prepared using ultra-sonicated assisted route.•Toluene was used for the first time as dispersive medium for these nanohybrids.•Improvement in electrochemical properties of was evident with increasing MWCNTs contents.•High rate-capacity, superior cycling stability and enhanced Columbic efficiency were observed.•These nanohybrids can be the promising candidates for anode materials of Lithium-ion batteries.
Abstract
Nanofibrils play a pivotal role in spider silk and are responsible for many of the impressive properties of this unique natural material. However, little is known about the internal ...structure of these protein fibrils. We carry out polarized Raman and polarized Fourier-transform infrared spectroscopies on native spider silk nanofibrils and determine the concentrations of six distinct protein secondary structures, including β-sheets, and two types of helical structures, for which we also determine orientation distributions. Our advancements in peak assignments are in full agreement with the published silk vibrational spectroscopy literature. We further corroborate our findings with X-ray diffraction and magic-angle spinning nuclear magnetic resonance experiments. Based on the latter and on polypeptide Raman spectra, we assess the role of key amino acids in different secondary structures. For the recluse spider we develop a highly detailed structural model, featuring seven levels of structural hierarchy. The approaches we develop are directly applicable to other proteinaceous materials.
Incidence and prevalence of cancer is an alarming situation globally. For the treatment of cancer many anticancer drugs have been developed but, unfortunately, their potential cardiotoxic side ...effects raised serious concerns about their use among clinicians. Cyclophosphamide is a potent anticancer and immunosuppressant drug but its use is limited due to cardiotoxic side effect. Thus, there is a need for the development of certain drug which can reduce cardiotoxicity and can be used as an adjuvant therapy in cancer patients. In this direction we, therefore planned to evaluate nerolidol (NER) for its cardioprotective potential against cyclophosphamide-induced cardiotoxicity in Swiss Albino mice. Animals were divided into 6 groups. Vehicle control; Cyclophosphamide (CP 200); NER 400 per se; NER 200 + CP 200; NER 400 + CP 200; and fenofibrate (FF 80) + CP 200. Dosing was done for 14 days along with a single dose of CP 200 on the 7th day. On 15th day animals were sacrificed and various biochemical parameters pertaining to oxidative stress, nitrative stress, inflammation, apoptosis and fibrosis were estimated in the blood and heart tissues. Histopathological analysis (H & E and Masson's trichrome staining); ultrastructural analysis (transmission electron microscopy) and immunohistochemical analysis were also performed along with mRNA expression and molecular docking to establish the cardioprotective potential of nerolidol. Nerolidol acted as a potent cardioprotective molecule and attenuated CP-induced cardiotoxicity.
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Ischemic reperfusion (I/R) injury causes a wide array of functional and structure alternations of mitochondria, associated with oxidative stress and increased the severity of injury. Despite the ...previous evidence for N-acetyl-L-cysteine (NAC) provide neuroprotection after I/R injury, it is unknown to evaluate the effect of NAC on altered mitochondrial autophagy forms an essential axis to impaired mitochondrial quality control in cerebral I/R injury.
Male wistar rats subjected to I/R injury were used as transient Middle Cerebral Artery Occlusion (tMCAO) model. After I/R injury, the degree of cerebral tissue injury was detected by infarct volume, H&E staining and behavioral assessment. We also performed mitochondrial reactive oxygen species and mitochondrial membrane potential by flow cytometry and mitochondrial respiratory complexes to evaluate the mitochondrial dysfunction. Finally, we performed the western blotting analysis to measure the apoptotic and autophagic marker.
We found that NAC administration significantly ameliorates brain injury, improves neurobehavioral outcome, decreases neuroinflammation and mitochondrial mediated oxidative stress. We evaluated the neuroprotective effect of NAC against neuronal apoptosis by assessing its ability to sustained mitochondrial integrity and function. Further studies revealed that beneficial effects of NAC is through targeting the mitochondrial autophagy via regulating the GSK-3β/Drp1mediated mitochondrial fission and inhibiting the expression of beclin-1 and conversion of LC3, as well as activating the p-Akt pro-survival pathway.
Our results suggest that NAC exerts neuroprotective effects to inhibit the altered mitochondrial changes and cell death in I/R injury via regulation of p-GSK-3β mediated Drp-1 translocation to the mitochondria.
Cyclophosphamide (CP), although a potent anti-cancer drug, causes cardiotoxicity as a side effect that limits its use. Hence, a specific medicine that can lower cardiotoxicity and be utilised as an ...adjuvant in cancer treatment is very much needed. In this light, we intended to assess the protective potential of levocabastine (LEV) on CP-induced cardiotoxicity in Swiss albino mice. Mice were administered LEV (50 and 100 μg/kg, i.p.) daily for 14 days and CP at 200 mg/kg, intraperitoneally once on the 7th day. On the 15th day, mice were weighed, blood withdrawn then sacrificed and hearts were removed to estimate various biochemical and histopathological parameters. CP 200 mg/kg significantly increased cardiac troponin T, LDH, CK-MB, interleukin-1β, IL-6, TNF-α, TBARS, nitrite, and decreased CAT, GSH, and SOD levels, thus, manifested cardiac damage, inflammation, oxidative stress, and nitrative stress, cumulatively causing cardiotoxicity. CP also elevated the expression of various markers including cleaved caspase-3, NF-κB, TLR4, NLRP3, and fibrotic lesions in cardiac tissues, whereas decreased hematological parameters (RBCs, platelets, and Hb) to confirm cardiotoxicity. LEV and fenofibrate (FF) treatment reversed these changes towards normal and showed a significant protective effect against CP. The results showed the protective role of LEV in restoring CP-induced cardiotoxicity in terms of inflammation, apoptosis, oxidative stress, cardiac injury and histopathological damage. Thus, levocabastine can be used as an adjuvant to cyclophosphamide in cancer treatment but a thorough study with various animal cancer models is further needed to establish the fact.
•Levocabastine protected cyclophosphamide-induced cardiotoxicity in Swiss mice.•Levocabastine reverted oxidative stress, inflammation, apoptosis and fibrosis.•Levocabastine decreased cleaved caspase-3, NF-κB, TLR4 and NLRP3 expression.•Levocabastine decreased cTnT, LDH, CK-MB, IL-1β, IL-6 and TNF-α.
Benzimidazole, a fused heterocycle bearing benzene and imidazole has gained considerable attention in the field of contemporary medicinal chemistry. The moiety is of substantial importance because of ...its wide array of pharmacological activities. This nitrogen containing heterocycle is a part of a number of therapeutically used agents. Moreover, a number of patents concerning this moiety in the last few years further highlight its worth. The present review covers the recent work published by scientists across the globe during last five years.
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•Benzimidazole: nitrogen containing bicyclic heterocyclic ring with diverse pharmacological activities.•Benzimidazole derivatives reported in the last quinquennial period have been discussed.•Various bioactivities such as anti-cancer, anti-microbial, antiviral and others have been highlighted.•A brief outline on the Structure activity relationship (SAR) study has been discussed.•This review will be helpful for medicinal chemists in designing future drugs.
Pyrazolines: a biological review Marella, Akranth; Ali, Md Rahmat; Alam, Md Tauquir ...
Mini reviews in medicinal chemistry,
05/2013, Letnik:
13, Številka:
6
Journal Article
Recenzirano
Pyrazoline is an important five membered nitrogen heterocycle, which has been extensively researched upon. The ring is quite stable and has inspired chemists to carry out various structural ...variations in the ring. This has propelled the development of distinct pyrazolines with an array of pharmacological activities viz. anti-inflammatory, analgesic, antimicrobial, anticancer, antidepressant etc. The review aims at highlighting this pharmacological diversity of pyrazolines. The review is a gist of latest work done describing the pharmacological aspects and potential of pyrazoline ring.
