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Aim This study is primarily designed to investigate the potential neuroprotective effects of polyphenol against 6-OHDAcaused neurotoxicity on SH-SY5Y cells. Materials and Methods Cytotoxic effect of 6-OHDA and valuable role of quercetin, myricetin and kaempferol on SH-SY5Y cells were analyzed by MTT assay. Generation of 6-OHDA-stimulated reactive oxygen species (ROS) was measured using DCFDA fluorescence dye. Alteration of 6-OHDA-caused mitochondrial membrane potential and nuclear condensation was investigated with the help of rhodamine-123 and hoechest stain. Immunoblotting was performed to detect the expression level of 6-OHDA-caused alpha-synuclein (á-syn), Bcl-2 associated protein X (BAX), caspase 3, cleaved Poly ADP – ribose polymerase (PARP) and Bcell lymphoma 2 proteins (Bcl-2). Result Through MTT assay, quercetin was selected over myricetin and kaempferol to counter 6-OHDA-caused cell death. The research delves into unraveling the intricate mechanisms underlying 6-OHDA-induced neurotoxicity, encompassing alterations in cellular morphology, escalation of oxidative stress, perturbation in mitochondrial membrane potential, and nuclear condensation. Exposure to 6-OHDA is implicated in the upregulation of á-syn protein, contributing to the aggravation of neurotoxicity. Concurrently, 6-OHDA orchestrates the apoptotic pathway by upregulating the expression of proapoptotic proteins such as BAX, caspase 3, and PARP, while down regulating the expression of the Bcl-2, affirming its role in apoptosis induction. Quercetin demonstrated ability to attenuate the expression of á-syn in the presence of 6-OHDA-caused injury in SH-SY5Y cells. Conclusion Taken together, these findings collectively underscore the therapeutic potential of quercetin as a promising agent against neurotoxicity caused by 6-OHDA. [ABSTRACT FROM AUTHOR]

Neurodegenerative diseases (NDs) cause cell dysfunction with a gradual loss of neurons in the central nervous system and aberrant accumulation of aggregated proteins such as synuclein, tau, and amyloid. Alzheimer's disease and Parkinson's disease are the two frequently occurring neurodegenerative disorders. Nanobiotechnology being an emerging field used in applied biotechnology holds great potential for the advancement of treatments. This review aims to give a brief but comprehensive idea about the possibilities of utilizing the advanced nanotechnological aspect to treat the Alzheimer's and Parkinson's NDs that can be explored through proper investigations. In the present study, various kinds of literature were surveyed and reviewed to appreciate the neurodegenerative disease manifestation. It is becoming challenging to treat and discuss the potentiality of effective nano-mediated treatment strategies for Alzheimer's and Parkinson's diseases. The capability of current drugs to cross the blood-brain barrier (BBB) makes NDs' treatment even more challenging. Recent therapies for such kinds of diseases are focused on symptomatic relief. Nanoparticulate drug delivery systems address all the challenges from all aspects and offer novel therapeutics for NDs. With targeted drug delivery of the required drug or protein to the site of interest, this approach is expected to turn out to be an exact and advanced therapeutic approach. [ABSTRACT FROM AUTHOR]

An increase in anthropogenic activities results in metal contamination in the ecosystem which has proven to be a major health risk in humans, as they make entry into cellular organelles via agricultural products. Copper (Cu) is one such metal that acts as an essential cofactor for the activity of several enzymes, one being the cytochrome c oxidase. The increasing number of evidence suggests a substantial correlation of Cu overload with neurodegenerative disorders, including Parkinson's disease (PD). We aim to explore quercetin, a well-known polyphenol, as an alternative for combating Cu-induced toxicity in human neuroblastoma SH-SY5Y secondary cell lines. We observed that Cu increased intracellular reactive oxygen species (ROS) levels, triggered morphological deformities and condensation of nuclei, caused an imbalance in the mitochondrial membrane potential (MMP), and finally induced apoptotic cell deaths. We further investigated the effects of Cu in modulating the pro- and anti-apoptotic proteins, such as Bax, Bcl-2, etc. However, quercetin reversed these changes owing to its antioxidant and anti-apoptotic properties, resulting in autophagy induction as an outcome of upregulation of autophagosome-bound microtubules-associated protein light chain-3 (LC3II). Besides, we investigated the role of Cu in stimulating ER stress proteins, viz. PERK, CHOP, and the concomitant responses of quercetin in restoring the ER homeostasis in cellular organelles like mitochondria and ER, against Cu-induced toxic insults by modulating autophagic pathways. Overall, this research work proposes a remedial approach for Cu-mediated neurotoxicity through understanding the diverse molecular signaling inside a cell with an aim to develop effective therapeutics. [ABSTRACT FROM AUTHOR]

In this paper, ultra-low level selective detection of bovine serum albumin (BSA) has been demonstrated, based on chemically derived graphene i.e., reduced graphene oxide (RGO) nanosheets. The working principle of the sensor is based upon change in conductance of the RGO nanosheets with different concentration of BSA. The change in conductance is based on the charge transfer between BSA and functional groups of RGO. The morphological and structural characterizations of RGO nanosheets were carried out by scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Raman spectroscopy is performed to further validate the interaction between RGO sensing layer and BSA molecules. Electrical impedance spectroscopy is performed to observe the impedance variation when BSA interacts with RGO. The sensor device exhibits sensitivity of 10 nA/pM. The lower limit of detection (LOD) of the sensor is found to be 1 pM and response time around 35 s, confirming very high sensitivity for BSA. All electrical (current-voltage) measurements were carried out at 2 V bias for low power operation. The sensor exhibits highest sensitivity at 30 °C and for RGO thickness ~4 nm. The RGO based sensor device is selective towards BSA when compared to proteins like L-Histidine, HSA, BHB and Biotin. Our results suggest that RGO based devices are promising for low-cost, portable and real time detection of BSA at room temperature. [ABSTRACT FROM AUTHOR]

Single-Walled Carbon Nanotubes (SWCNTs) are widely used as potential carriers in drug delivery systems. The objective of this work was to observe the effects of pristine, and single-stranded DNA oligonucleotide functionalized SWCNT over the locomotion pattern in the nematode model, Caenorhabditis elegans. The implication of ssDNA in the as-modified SWCNT has been understood in terms of lowering the toxic effects of the pristine SWCNT and thereby normalizing the altered navigation pattern of the worms. Chemotaxis assay displayed an increased migration of the worms towards pristine and ssDNA functionalized SWCNT in comparison to ultrapure water as control. Additionally, paralytic movement was observed with SWCNT exposure in contrast to ssDNA-functionalized SWCNT-exposed animals. High doses of pristine SWCNT further displayed an increased expression of specific proteins obtained from the total protein extracts of the animals. Thus, the alteration in the navigation pattern of the worms, treated with pristine SWCNT, might be ascribed as a result of differentially expressed muscle proteins. Moreover, it is interesting to note that the modified SWCNT was effective in alleviating the atypical form of the inherent movements of the worm. Future investigation will further reveal the protein targets responsible for the altered navigation pattern of the worms. [ABSTRACT FROM AUTHOR]

Functionalized carbon nanotubes are recommended as potential drug-delivery tools due to their reduced toxicity and increased solubility or wettability. However, their applications are still restricted because of their dose- and time-dependent toxicity. The conflicting reports regarding toxicity assays of pristine and functionalized multiwalled carbon nanotubes (MWCNTs) in different in vivo and in vitro models inspired us to design a safe drug-releasing device and investigate its applicability in a widely used human-analogous in vivo model. We thereby propose a biocompatible drug-delivery vector that is nontoxic even at higher doses in the Caenorhabditis elegans nematode model. We further carried out a comparative analysis of the various biocompatibility assays of MWCNTs functionalized with inorganic and organic molecules. Synthetic single-stranded DNA (ssDNA) oligonucleotide (5′-GGG-GGG-GGG-G-3′)-functionalized MWCNTs were found to be the most biocompatible and nontoxic even at higher doses (320 µg/mL) of MWCNTs. In contrast, pristine and NH2-functionalized MWCNT were proven to be toxic at lower doses (20–160 µg/mL) of MWCNTs based on survival, locomotion, reproductive potential, and oxidative-stress-related endpoints. Thus, the order of cytotoxicity in animals was observed to be as follows: pristine MWCNTs > NH2-functionalized MWCNTs > ssDNA-functionalized MWCNT. [ABSTRACT FROM AUTHOR]

In this study, electronic properties of Manganese atom doped Graphene are studied using Atomistix Tool Kit-Virtual NanoLab (ATK-VNL), QuantumWise simulation package. All the calculations are done using density functional theory. The doping of Manganese atom creates a small band gap and this gap increases with increasing doping concentrations. Chemical potential measurements exhibit a rise in the values for pristine Graphene is − 10.48 to − 9.91 eV for single doped atom to − 9.87 eV for double doped Manganese atom to − 9.57 eV for triple atom doped Manganese. Total energy calculated for pristine, one, two and three Manganese atom doped Graphenes are as − 4506.6, − 4599.5, − 4691.97 and − 4789.31 eV, respectively. Optical spectrum plots also support the aforementioned characteristics deviation in the pristine Graphene. Transmission spectrum is also varied for pristine Graphene in comparison to one, two and three Manganese atom doped nanosheets. Density of states calculations also illustrates the rise in the values for the number of states occupied by electrons for pristine Graphene, one to three Manganese atom doped nanosheet, respectively. The flow of current reduces with increasing number of impure atoms. Understanding the effect of Manganese as dopant at different lattice sites of 2D-Graphene helps in designing conductivity tunable Graphene based electro-mechanical devices and sensors for myriad nanoelectronic applications. [ABSTRACT FROM AUTHOR]

The detrimental impact on the food chain due to the overuse of rotenone is partly responsible for alpha-synuclein (α-syn) mediated neurotoxicity. It is hypothesized that rotenone overdose leads to cytosolic proteopathy resulting in modulation of apoptosis and autophagic pathways. The aim of our study is to explore the neuroprotective role of quercetin, a beneficial polyphenol against rotenone-induced neurotoxicity in dopaminergic human SH-SY5Y cell lines. In our study we demonstrated the correlation of rotenone-induced neurotoxicity through elevation of intracellular reactive oxygen species (ROS) and imbalance in the mitochondrial membrane potential (MMP). Moreover, the morphological distortion of cell, condensation of nuclei, externalization of the inner phosphatidylserine, cleavage of caspase 3, and Poly ADP Ribose Polymerase (PARP) confirmed apoptosis. However, all these lethal effects were ameliorated by treatment of quercetin to the cells. On the other hand rotenone has a strong effect on autophagy which is a regulated degrading and recycling cellular process to remove dysfunctional proteins. Indeed, rotenone-mediated autophagy resulted in the enhancement of autophagosome-bound microtubule-associated protein light chain-3 (LC3-II) expression. Furthermore, excess accumulation of acidic vesicles was detected in presence of rotenone. Lysosome associated membrane protein (LAMP-2A) is yet another crucial protein that recruits overexpressed or misfolded proteins into the lumen of lysosome to trigger autophagy. In all cases the impact of rotenone on the cells acquired significant protection through quercetin treatment. In the present work we therefore opine the prospects of quercetin as a therapeutic candidate against neurotoxicity. [ABSTRACT FROM AUTHOR]

DEHP (Di-ethyl hexyl phthalate), an ubiquitous chemical constituent of plasticizer, cosmetics etc. poses different abnormal neurological and behavioral responses in eukaryotic model organism C. elegans (Caenorhabditis elegans). Based upon such reports, we hypothesized that due to exposure of DEHP, the larval growth of C. elegans was altered and animals went into dauer at high concentrations of exposure at 8.26 ppm. Using chemosensory assay, the orientation of repulsion (− 0.1) of the nematodes were determined with exposure of DEHP at 4.78 ppm and 8.26 ppm. We show that N2 wild type worms display a preferential food choice and search for favorable food, and alter two modes of locomotion (forward and backward) that measures the maximum bending rate of an adult worm. Thermo sensation also plays a crucial role in determining the toxicity level in C. elegans at 15 °C, 20 °C, and 25 °C. Understanding the chemosensory pattern towards a specific chemical for C. elegans, the recent work could shed light in exploring the molecular mechanism involved in the tactile movement of the worms against a specific chemical, thereby making worms a potential biological sensing platform for external stimuli perception. [ABSTRACT FROM AUTHOR]

Iron accumulation plays a major role in neuronal cell death which has severe effects on mental health like neurodegenerative disorders. The present work aims to explore the involvement of molecular pathways involved in iron-mediated neuronal cell death using Ferric Ammonium Citrate (FAC) as a source of iron to treat neuroblastoma SH-SY5Y cells. In this study, it was found that cytotoxicity induced by iron treatment is highly correlated with enhanced intracellular reactive oxygen species (ROS) generation and loss of mitochondrial integrity. Appearance of early and late apoptotic cells with altered nuclear morphology and increased expression of effector proteins, i.e., cleaved Caspase 3 and cleaved PARP (Poly-ADP-ribose Polymerase), clearly confirmed iron-induced apoptotic cell deaths. Furthermore, excess accumulation of acidic vesicles and microtubule-associated protein 1 light chain 3 (LC3) puncta and LC3II/I expressions were observed. Simultaneously, ultrastructural studies of SH-SY5Y cells demonstrated the accumulation of a large number of autophagosomes, autophagic vacuolization, and swollen mitochondria which further confirmed the induction of autophagy concomitant with mitochondrial damage. Furthermore, increased incorporation of lysosome-specific dye, LysoTracker Deep Red, and the red fluorescence retention of LC3-GFP-RFP constructs indicates the incomplete autophagy or autophagy dysfunction due to altered lysosomal activity. Hence, the present work unveiled the interruption in autophagy progression caused by the plausible suppression of lysosomal activity due to iron treatment resulting in autophagic cell death in SH-SY5Y cell lines. In general, both apoptotic and autophagic pathways were prominent and each of the pathways played their prospective roles, in iron-mediated neuronal cell death. [ABSTRACT FROM AUTHOR]

Graphene has been conjugated with Silicene which is a 2D nanosheet of silicon crystal to analyze myriad physico-chemical properties. Upon intercalation of silicene between two graphene nanosheets, there has been a significant shift in the energy of electronic configuration at different isovalues from − 0.12 to + 0.12. Similarly, by analyzing the electronic energy states of silicene–graphene–silicene, a range of isovalues from − 0.08 to + 0.08 were observed. I–V curve exhibited a linear response for graphene–silicene–graphene sandwiched structure and a semiconducting like behavior for silicene–graphene–silicene structure. Band gap measurement in case of graphene–silicene–graphene system is reported to be ~ 0.18 eV, which is a narrow region. While in case of silicene–graphene–silicene, a band gap value of ~ 1.01 eV is calculated that appears to be a pretty broad region. Transmission spectrum also shows intensity in peaks for Gr–Si–Gr case as compared to Si–Gr–Si combinations. Silicon is widely perceived to exhibit outstanding semiconducting behavior and has already been used in devising various electronic devices. In this present work, we try to analyze the outcome of the silicene and graphene at the nanometer scale in various combinations in a bid to understand the potential interaction mechanism between the two nanosheets which would help in the fabrication of the silicene–graphene based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Conversion of the metallic SWCNT to semiconducting SWCNT was achieved by band structure engineering of the nanotube by functionalization of the DNA nucleobase, guanine. The band structure analysis revealed that metallic SWCNT (6, 0), when surface engineered with guanine nucleobase with H-atom attachment as the functional group, is converted to a semiconductor one by opening a narrow bandgap with a value of 0.08 eV. This phenomenon was brought about by strong chemisorption due to hydrogenation by inducing partial sp3 hybridization in the nanotube structure. No bandgap openings were observed when guanine was adsorbed on the pristine nanotube surface by its nitrogen site and oxygen site respectively. Related zero-bias transmission spectra and IV-curve supported the result also. The entire study was done at room temperature using ATK-VNL simulation software. [ABSTRACT FROM AUTHOR]

Pristine metallic single-walled carbon nanotubes (6, 0), surface engineered with pyrimidine type DNA nucleobases, thymine and cytosine respectively, are transformed into semimetal forms by band structure engineering of the nanotubes. The hybrid systems are designed using ATK–VNL simulation software. Band structure and zero bias transmission spectra analysis witness a very small overlap between the conduction and valence bands around the Fermi level. IV-characteristic curves also support the semimetallic nature of SWCNT–DNA nucleobase coupling. The altered electronic structure of SWCNT is achieved due to strong chemisorption imparted by hydrogenation of DNA nucleobases which induce partial sp3 hybridization in the nanotube structure. Metal to semimetal conversion results in conductivity modulation in SWCNT and it has several applications in various fields like nano-electronics including NEMS design. [ABSTRACT FROM AUTHOR]

The detection of a specific biothiol in a mixture of biothiols is a challenging task because of their similarity in structure and reactivity. To discriminate between glutathione (GSH) and cysteine (Cys)/homocysteine (Hcy) at physiological pH, the fluorometric “off–on” displacement approach was adopted, utilizing a Cu(ii)-complex of a Schiff-base ligand (L1) containing a phenolic aldimine group attached to a triazole moiety along with a dangling benzylic alcohol branch. The weakly fluorescent L1 (quantum yield (ΦF) ∼ 0.006) formed a non-fluorescent 1 : 1 Cu(ii)/L1 stoichiometric complex (1) and remained as a dimeric [Cu–L1]22+ species in an aqueous medium. The Cu(ii)-centre in 1 is highly susceptible to interactions with the –SH moiety of biothiol to participate in demetallation reactions. Unlike other solvents, the GSH-induced decomplexation of 1 generates strong fluorescence intensity in an aqueous medium, indicating the liberation of the modified L1 (L1′). Experimental evidence suggests that the benzylic alcohol moiety of L1 is itself oxidized to the formyl group during the course of the GSH interaction with 1. However, Cys/Hcy liberates L1 by the partial decomplexation of 1 (∼40%) in the usual displacement pathway to exhibit an intensity increase of less than 5% in comparison to GSH under similar experimental conditions. Unlike L1, there was an acidity increase by about 2.5 pH units for the phenolic-OH of L1′ (pKa∼ 7.0) with ∼65% phenol to fluorophoric phenolate conversion at pH 7.3, attributed to a large GSH-induced increase in the fluorescence intensity (ΦF = 0.18). It is proposed that GSH induced a comparatively rapid attack at the Cu(ii) center in 1, favouring the possibility for radical generation resulting in ligand modification of L1′ along with decomplexation. This is the first report of a biothiol-selective ligand modification exhibiting an “off–on” fluorescence response in the displacement strategy. For biogenic GSH detection and its effect on different biothiol quenchers, in vivo fluorescence imaging was carried out in the multicellular domain on Caenorhabditis elegans (C. elegans), as well as in living human neuroblastoma SH-SY5Y cells. GSH depletion in the presence of a pain killer drug, acetaminophen, was also monitored for C. elegans. [ABSTRACT FROM AUTHOR]

Two different morphological forms of graphene nanosheets: improved reduced graphene oxide (IRGO) and modified reduced GO (rGO) (MRGO) have been synthesised by improved and modified methods, respectively. Physical characterisations of these graphene nanosheets were carried out using X‐ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. Colloidal stability of these nanosheets toward a selected bacterium (e.g. Staphylococcus aureus) was ascertained by zeta potential. In the present study, the authors for the first time made an attempt to study and compare the potentialities of these two different forms of graphene nanosheets as efficient bactericidal agents. Field‐emission scanning electron microscopy and TEM with energy dispersive X‐ray spectroscopy (EDAX) studies of IRGO and MRGO have been carried out to explore their underlying mechanism of antibacterial responses through physical as well as chemical interactions with the selected bacterial species. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a complex neurological disorder where many pathogenic signaling cascades are simultaneously activated. Moreover, their inter-relations and molecular reasons for activations are not completely understood, which impedes the development of therapeutics for AD. Multi-target drug discovery has recently come into prominence, particularly in the case of AD, due to the ability of the potential hits to simultaneously inhibit many pathways causing the disease. The present study reports the application of an FDA approved sweetener, neohesperidin dihydrochalcone (NHD), as a multi-target inhibitor for AD therapeutics. NHD shows a high BACE1 and amyloid aggregation inhibition ability as well as strong anti-oxidant activity. NHD binds to the active site of BACE1 and thus induces a conformational transition to a closed complex, which excludes substrate recognition, evident from steady-state and time-resolved fluorescence spectroscopy. 500 nM NHD completely inhibits the activity of BACE1. 8-Anilino-1-naphthalenesulfonic acid (ANS), Thioflavin-T fluorescence assay and Atomic Force Microscopy (AFM) studies confirm that co-incubation of equimolar NHD with Aβ25–35 almost completely inhibits Aβ25–35 fibril formation. Co-incubation of NHD with Aβ25–35 entirely alleviates the neurotoxic effects of equimolar Aβ25–35. NHD dose-dependently inhibits Aβ25–35 induced cellular ROS generation. In vitro bio-assays confirm that NHD is itself a strong anti-oxidant and shows scavenging activity against a wide variety of radicals. Our results clearly indicate that NHD changes the aggregation pathways of Aβ in such a way that the formations of toxic oligomeric/fibrillar forms are reduced significantly. The present study demonstrates the multi-target inhibitory potency of NHD in AD therapeutics identified via drug repurposing screening. [ABSTRACT FROM AUTHOR]

Bio-synthesis of silver nanoparticles (AgNPs) was made by using the aqueous leaf extract of Ardisia solanacea. Rapid formation of AgNPs was observed from silver nitrate upon treatment with the aqueous extract of A. solanacea leaf. The formation and stability of the AgNPs in the colloidal solution were monitored by UV-visible spectrophotometer. The mean particle diameter of AgNPs was calculated from the DLS with an average size ~4 nm and ~65 nm. ATR-FTIR spectroscopy confirmed the presence of alcohols, aldehydes, flavonoids, phenols and nitro compounds in the leaf which act as the stabilizing agent. Antimicrobial activity of the synthesized AgNPs was performed using agar well diffusion and broth dilution method against the Gram-positive and Gram-negative bacteria. Further, robust anti-oxidative potential was evaluated by DPPH assay. The highest antimicrobial activity of synthesized AgNPs was found against Pseudomonas aeruginosa (28.2 ± 0.52 mm) whereas moderate activity was found against Bacillus subtilis (16.1 ± 0.76), Candida kruseii (13.0 ± 1.0), and Trichophyton mentagrophytes (12.6 ± 1.52). Moreover, the potential wound healing activity was observed against the BJ-5Ta normal fibroblast cell line. Current research revealed that A. solanacea was found to be a suitable source for the green synthesis of silver nanoparticles. [ABSTRACT FROM AUTHOR]

Bio‐ synthesis of silver nanoparticles (AgNPs) was made by using the aqueous leaf extract of Ardisia solanacea. Rapid formation of AgNPs was observed from silver nitrate upon treatment with the aqueous extract of A. solanacea leaf. The formation and stability of the AgNPs in the colloidal solution were monitored by UV–visible spectrophotometer. The mean particle diameter of AgNPs was calculated from the DLS with an average size ∼4 nm and ∼65 nm. ATR‐FTIR spectroscopy confirmed the presence of alcohols, aldehydes, flavonoids, phenols and nitro compounds in the leaf which act as the stabilizing agent. Antimicrobial activity of the synthesized AgNPs was performed using agar well diffusion and broth dilution method against the Gram‐positive and Gram‐negative bacteria. Further, robust anti‐oxidative potential was evaluated by DPPH assay. The highest antimicrobial activity of synthesized AgNPs was found against Pseudomonas aeruginosa (28.2 ± 0.52 mm) whereas moderate activity was found against Bacillus subtilis (16.1 ± 0.76), Candida kruseii (13.0 ± 1.0), and Trichophyton mentagrophytes (12.6 ± 1.52). Moreover, the potential wound healing activity was observed against the BJ‐5Ta normal fibroblast cell line. Current research revealed that A. solanacea was found to be a suitable source for the green synthesis of silver nanoparticles. [ABSTRACT FROM AUTHOR]

The Schiff base ligand (L1) showing large fluorescence intensity in an aqueous medium owing to a ground state intramolecular proton transfer (GSIPT) reaction was utilized in a complexation process to generate a highly stable non-fluorescent Cu(ii)/L1 (1) in its “turn-off” mode. The 3:2 Cu(ii)/L1 stoichiometric complex (1), isolated in the solid form, exhibited a cysteine (Cys)-induced “turn-on” fluorescence response with a unique time-dependent intensity variation. Unlike other biothiols, the partially deprotonated –SH moiety in Cys is highly susceptible for participating in an ionic interaction with Cu(ii)-centres in 1 at a physiological pH of ∼7.4, followed by reduction to Cu(i), and then a subsequent demetallation, resulting in a large increment of the fluorescence intensity for free fluorophoric L1, which persists for about 4 –13 min owing to an unexpected stability of the Cu(i) ions. After Cys consumption, Cu(i) ions in aqueous solution rapidly oxidize to participate further in complexation with the existing free L1. The resulting complex may again be susceptible to Cys-induced abovementioned decomplexation followed by complexation for at least four different external Cys additions in four successive cyclic pathways. This multiple Cys sensing behaviour has been exploited to recognize the existence of Cys in multicellular Caenorhabditis elegans (C. elegans). [ABSTRACT FROM AUTHOR]

A correction is presented to the article "In Vivo Biointeraction and Alleviation of Toxicity of MWCNTs upon Functionalization with ssDNA in a Caenorhabditis elegans Model" published in February 6, 2023 issue.

The present study reports on biogenic-synthesised silver nanoparticles (AgNPs) derived by treating Ag ions with an extract of Cassia fistula leaf, a popular Indian medicinal plant found in natural habitation. The progress of biogenic synthesis wasmonitored time to time using a ultraviolet-visible spectroscopy. The effect of phytochemicals present in C. fistula including flavonoids, tannins, phenolic compounds and alkaloids on the homogeneous growth of AgNPs was investigated by Fouriertransform infrared spectroscopy. The dynamic light scattering studies have revealed an average size and surface Zeta potential of the NPs as, -39.5 nm and -21.6 mV, respectively. The potential antibacterial and antifungal activities of the AgNPs were evaluated against Bacillus subtilis, Staphylococcus aureus, Candida kruseii and Trichophyton mentagrophytes. Moreover, their strong antioxidant capability was determined by radical scavenging methods (1,1-diphenyl-2-picryl-hydrazil assay). Furthermore, the AgNPs displayed an effective cytotoxicity against A-431 skin cancer cell line by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, with the inhibitory concentration (IC50) predicted as, 92.2 ± 1.2 µg/ml. The biogenically derived AgNPs could find immense scope as antimicrobial, antioxidant and anticancer agents apart from their potential use in chemical sensors and translational medicine. [ABSTRACT FROM AUTHOR]

The present study reports on biogenic‐synthesised silver nanoparticles (AgNPs) derived by treating Ag ions with an extract of Cassia fistula leaf, a popular Indian medicinal plant found in natural habitation. The progress of biogenic synthesis was monitored time to time using a ultraviolet–visible spectroscopy. The effect of phytochemicals present in C. fistula including flavonoids, tannins, phenolic compounds and alkaloids on the homogeneous growth of AgNPs was investigated by Fourier‐transform infrared spectroscopy. The dynamic light scattering studies have revealed an average size and surface Zeta potential of the NPs as, −39.5 nm and −21.6 mV, respectively. The potential antibacterial and antifungal activities of the AgNPs were evaluated against Bacillus subtilis, Staphylococcus aureus, Candida kruseii and Trichophyton mentagrophytes. Moreover, their strong antioxidant capability was determined by radical scavenging methods (1,1‐diphenyl‐2‐picryl‐hydrazil assay). Furthermore, the AgNPs displayed an effective cytotoxicity against A‐431 skin cancer cell line by 3‐(4, 5‐dimethylthiazol‐2‐yl)‐2, 5‐diphenyltetrazolium bromide (MTT) assay, with the inhibitory concentration (IC50) predicted as, 92.2 ± 1.2 μg/ml. The biogenically derived AgNPs could find immense scope as antimicrobial, antioxidant and anticancer agents apart from their potential use in chemical sensors and translational medicine. [ABSTRACT FROM AUTHOR]

The Caenorhabditis elegans peroxidasins, PXN-1 and PXN-2, are extracellular peroxidases; pxn-2 is involved in muscleepidermal attachment during embryonic morphogenesis and in specific axon guidance. Here we investigate potential roles of the other homologue of peroxidasin, pxn-1, in C. elegans. A pxn-1 deletion mutant showed high lethality under heat-stress conditions. Using a transcriptional GFP reporter, pxn-1 expression was observed in various tissues including neurons, muscles, and hypodermis. A translational fusion showed that PXN-1::GFP was secreted and localized in extracellular matrix, particularly along body wall muscles and pharyngeal muscles. Various neuronal developmental defects were observed in pxn-1 mutants and in pxn-1 over-expressing animals, including handedness, branching, breakage, tangling, and defasciculation. These results suggest that pxn-1, like other peroxidasins, plays an important role throughout development. [ABSTRACT FROM AUTHOR]

NOG1 is a nucleolar GTPase that is critical for 60S ribosome biogenesis. Recently, NOG1 was identified as one of the downstream regulators of target of rapamycin (TOR) in yeast. It is reported that TOR is involved in regulating lifespan and fat storage in Caenorhabditis elegans. Here, we show that the nog1 ortholog (T07A9.9: nog-1) in C. elegans regulates growth, development, lifespan, and fat metabolism. A green fluorescence protein (GFP) promoter assay revealed ubiquitous expression of C. elegans nog-1 from the early embryonic to the adult stage. Furthermore, the GFP-tagged NOG-1 protein is localized to the nucleus, whereas the aberrant NOG-1 protein is concentrated in the nucleolus. Functional studies of NOG-1 in C. elegans further revealed that nog-1 knockdown resulted in smaller broodsize, slower growth, increased life span, and more fat storage. Moreover, nog-1 over-expression resulted in decreased life span. Taken together, our data suggest that nog-1 in C. elegans may be an important player in regulating life span and fat storage via the insulin/IGF pathway. [ABSTRACT FROM AUTHOR]

Calcineurin, a well-conserved protein phosphatase 2B (PP2B), is a Ca-calmodulin-dependent serine/threonine protein phosphatase that is known to be involved in a myriad of cellular processes and signal transduction pathways. The biological role of calcineurin has been extensively studied in diverse groups of organisms. Homologues of mammalian and Drosophila calcineurin subunits exist in the nematode, Caenorhabditis elegans. The C. elegans counterpart of the catalytic subunit, calcineurin A, cna-1/ tax-6, and the regulatory subunit, calcineurin B, cnb-1, are known to express ubiquitously in multiple tissues including neurons. The characterization of C. elegans calcineurin mutants facilitates identification of its physiological functions and signaling pathways. Genetic interactions between cna-1/ tax-6 and cnb-1 mutants with a number of mutants involved in several signaling pathways have exemplified the pivotal role of calcineurin in regulating nematode development, behaviour and lifespan (aging). The present review has been aimed to provide a succinct summary of the multiple functions of calcineurin in C. elegans relating to its development, fertility, proliferation, behaviour and lifespan. Analyses of cna-1/ tax-6 and cnb-1 interacting proteins and regulators of the phosphatase in this fascinating worm model have an immense scope to identify potential drug targets in various parasitic nematodes, which cause many diseases inflicting huge economic loss; and also for many human diseases, particularly neurodegenerative and myocardial diseases. [ABSTRACT FROM AUTHOR]

Thioredoxin reductase (TrxR) is a member of the pyridine nucleotide-disulfide reductase family, which mainly functions in the thioredoxin system. TrxR is found in all living organisms and exists in two major ubiquitous isoenzymes in higher eukaryotic cells; One is cytosolic and the other mitochondrial. Mitochondrial TrxR functions to protect mitochondria from oxidative stress, where reactive oxidative species are mainly generated, while cytosolic TrxR plays a role to maintain optimal oxido-reductive status in cytosol. In this study, we report differential physiological functions of these two TrxRs in C. elegans. trxr-1, the cytosolic TrxR, is highly expressed in pharynx, vulva and intestine, whereas trxr-2, the mitochondrial TrxR, is mainly expressed in pharyngeal and body wall muscles. Deficiency of the non-selenoprotein trxr-2 caused defects in longevity and delayed development under stress conditions, while deletion mutation of the selenoprotein trxr-1 resulted in interference in acidification of lysosomal compartment in intestine. Interestingly, the acidification defect of trxr-1(jh143) deletion mutant was rescued, not only by selenocystein-containing wild type TRXR-1, but also cysteine-substituted mutant TRXR-1. Both trxr-1 and trxr-2 were up-regulated when worms were challenged by environmental stress such as heat shock. These results suggest that trxr-1 and trxr-2 function differently at organismal level presumably by their differential sub-cellular localization in C. elegans. [ABSTRACT FROM AUTHOR]

Calcineurin is a calcium/calmodulin-dependent serine/threonine protein phosphatase. It is a heterodimeric protein consisting of a catalytic subunit calcineurin A, and a regulatory calcium-binding subunit, calcineurin B. The primary sequence of both subunits and heterodimeric structure is highly conserved from yeast to mammals. Calcineurin has long been implicated in various signaling pathways. Calcineurin genes (cna- 1/tax-6 and cnb-1) have been identified in the nematode Caenorhabditis elegans, which share high homology with their Drosophila and mammalian counterparts. C. elegans calcineurin binds calcium and functions as a heterodimeric protein phosphatase establishing its biochemical conservation. Calcineurin expresses in diverse tissues implicating its important role in various physiological processes. This review will focus in brief on the expression pattern and regulation of calcineurin including its effect on growth and development, locomotion, egg-laying, and sensory responses. [ABSTRACT FROM AUTHOR]

Presents information on a study which discussed the pulse propagation effects on lossy thin film planes. Film plane architecture; Description of the wide band frequency domain model; Measurement to modeling correlation.

Specific binding of Hg to ouabain-sensitive Na-K-ATPase of rat liver plasma membrane was demonstrated with a K of 2.64¥10 and B of 1.6nmole mg protein. The binding of mercury to the enzyme also causes significant inhibition of the enzyme, which is greater than its ouabain sensitivity. In the cytosol Hg binding to reduced glutathione (GSH) is stimulated by GSH-S-transferase (GST), the activity of which was found to be significantly enhanced by 15mM Na and 10mM Hg. It is proposed that the transport of Hg2 inside the cell takes place by increased dissociation of Hg from the membrane due to greater avidity of Hg towards cytosolar GSH binding. The GSH-Hg complex enters the nucleus where it dissociates to bind the metal response element (MRE) of the metallothionein (MT) gene to induce MT transcription. [ABSTRACT FROM AUTHOR]