scholarly journals Photodegradation Behaviour of Nitrogen-Containing Graphene Derivatives Towards Pollutant Dyes and Real-TimeAssessment on Aquatic Weed

2021 ◽  
Vol 12 (4) ◽  
pp. 4357-4373
Keyword(s):  
Lemna Minor ◽  
Single Step ◽  
Aquatic Weed ◽  
Complex Structures ◽  
Atmospheric Conditions ◽  
Hexagonal Array ◽  
Substantial Growth ◽  
Graphene Derivatives ◽  
Real Time Application

Discharge of dyes in the aquatic system is ubiquitous environmental chaos, and combating this particular anthropogenic issue with graphene-based materials via photodegradation process has been a radiant approach in recent times. In this work, 3-aminophenol produced nanosheets of N-graphene (NG) in the presence of urea in a single step at a relatively low temperature of ~ 120 – 125°C in contrast to nitrogen-containing graphene oxide (NGO) produced in the absence of urea. The V- shape of urea facilitated the formation of a poly-hexagonal array of rings and prevented the attack of oxygen at normal atmospheric conditions. During the comparison of the photodegradation ability of both NG and NGO against MG, MB, and MO, the degradation efficiency was found to be 92 - 99%. Further LC-MS/MS studies proved that NGO was capable of mineralizing the complex structures of the dyes via the demethylation route initially followed by asymmetric cleaving at neutral pH. The in-vitro real-time application of an aquatic weed (Lemna minor) was also compared against the 1:1:1 ratio of MG, MB, MO, and NGO-treated dye water. No substantial growth of Lemna minor was found in the case of using the dye mixture even up to the 20th day, whereas rapid growth of this aquatic weed was observed within 15 days in the case of NGO treated dye mixture.

Functionalized Nano-graphene Oxide as Multi-modal Clinic for Effective Drug Delivery

2017 ◽  
Vol 10 (4) ◽  
pp. 3768-3771
Author(s):  
Soumitra Satapathi ◽  
Rutusmita Mishra ◽  
Manisha Chatterjee ◽  
Partha Roy ◽  
Somesh Mohapatra
Keyword(s):  
Drug Delivery ◽  
Graphene Oxide ◽  
Cancer Cell ◽  
High Surface ◽  
High Surface Area ◽  
Cancer Cell Line ◽  
Xrd Analysis ◽  
Graphene Derivatives ◽  
Nano Graphene

Nano-materials based drug delivery modalities to specific organs and tissues has become one of the critical endeavors in pharmaceutical research. Recently, two-dimensional graphene has elicited considerable research interest because of its potential application in drug delivery systems. Here we report, the drug delivery applications of PEGylated nano-graphene oxide (nGO-PEG), complexed with a multiphoton active and anti-cancerous diarylheptanoid drug curcumin. Specifically, graphene-derivatives were used as nanovectors for the delivery of the hydrophobic anticancer drug curcumin due to its high surface area and easy surface functionalization. nGO was synthesized by modified Hummer’s method and confirmed by XRD analysis. The formation of nGO, nGO-PEG and nGO-PEG-Curcumin complex were monitored through UV-vis, IR spectroscopy. MTT assay and AO/EB staining found that nGO-PEG-Curcumin complex afforded highly potent cancer cell killing in vitro with a human breast cancer cell line MCF7.

scholarly journals A Nitronaphthalimide Probe for Fluorescence Imaging of Hypoxia in Cancer Cells

2021 ◽  
Author(s):  
Rashmi Kumari ◽  
Vasumathy R ◽  
Dhanya Sunil ◽  
Raghumani Singh Ningthoujam ◽  
Badri Narain Pandey ◽  
...  
Keyword(s):  
Fluorescence Imaging ◽  
Tumor Hypoxia ◽  
Binding Pocket ◽  
Docking Studies ◽  
Single Step ◽  
Naphthalic Anhydride ◽  
Hypoxic Conditions ◽  
Fluorescence Measurements ◽  
Enzymatic Reduction

AbstractThe bioreductive enzymes typically upregulated in hypoxic tumor cells can be targeted for developing diagnostic and drug delivery applications. In this study, a new fluorescent probe 4−(6−nitro−1,3−dioxo−1H−benzo[de]isoquinolin−2(3H)−yl)benzaldehyde (NIB) based on a nitronaphthalimide skeleton that could respond to nitroreductase (NTR) overexpressed in hypoxic tumors is designed and its application in imaging tumor hypoxia is demonstrated. The docking studies revealed favourable interactions of NIB with the binding pocket of NTR-Escherichia coli. NIB, which is synthesized through a simple and single step imidation of 4−nitro−1,8−naphthalic anhydride displayed excellent reducible capacity under hypoxic conditions as evidenced from cyclic voltammetry investigations. The fluorescence measurements confirmed the formation of identical products (NIB-red) during chemical as well as NTR−aided enzymatic reduction in the presence of NADH. The potential fluorescence imaging of hypoxia based on NTR-mediated reduction of NIB is confirmed using in-vitro cell culture experiments using human breast cancer (MCF−7) cells, which displayed a significant change in the fluorescence colour and intensity at low NIB concentration within a short incubation period in hypoxic conditions. Graphical abstract

scholarly journals Anti-TNF Alpha Antibody Humira with pH-dependent Binding Characteristics: A constant-pH Molecular Dynamics, Gaussian Accelerated Molecular Dynamics, and In Vitro Study

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 334
Author(s):  
Shih-Ting Hong ◽  
Yu-Cheng Su ◽  
Yu-Jen Wang ◽  
Tian-Lu Cheng ◽  
Yeng-Tseng Wang
Keyword(s):  
Molecular Dynamics ◽  
Tnf Alpha ◽  
Complex Structures ◽  
Binding Characteristics ◽  
Accelerated Molecular Dynamics ◽  
Constant Ph ◽  
Ph Dependent ◽  
Constant Ph Molecular Dynamics ◽  
Antibody Drug

Humira is a monoclonal antibody that binds to TNF alpha, inactivates TNF alpha receptors, and inhibits inflammation. Neonatal Fc receptors can mediate the transcytosis of Humira–TNF alpha complex structures and process them toward degradation pathways, which reduces the therapeutic effect of Humira. Allowing the Humira–TNF alpha complex structures to dissociate to Humira and soluble TNF alpha in the early endosome to enable Humira recycling is crucial. We used the cytoplasmic pH (7.4), the early endosomal pH (6.0), and pKa of histidine side chains (6.0–6.4) to mutate the residues of complementarity-determining regions with histidine. Our engineered Humira (W1-Humira) can bind to TNF alpha in plasma at neutral pH and dissociate from the TNF alpha in the endosome at acidic pH. We used the constant-pH molecular dynamics, Gaussian accelerated molecular dynamics, two-dimensional potential mean force profiles, and in vitro methods to investigate the characteristics of W1-Humira. Our results revealed that the proposed Humira can bind TNF alpha with pH-dependent affinity in vitro. The W1-Humira was weaker than wild-type Humira at neutral pH in vitro, and our prediction results were close to the in vitro results. Furthermore, our approach displayed a high accuracy in antibody pH-dependent binding characteristics prediction, which may facilitate antibody drug design. Advancements in computational methods and computing power may further aid in addressing the challenges in antibody drug design.

scholarly journals Long-term effects of the proline-rich antimicrobial peptide Oncocin112 on the Escherichia coli translation machinery

2020 ◽  
Vol 295 (38) ◽  
pp. 13314-13325
Author(s):  
Yanyu Zhu ◽  
James C. Weisshaar ◽  
Mainak Mustafi
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Peptides ◽  
Binding Site ◽  
Elongation Factor ◽  
Microscopy Study ◽  
Single Step ◽  
Long Term Effects ◽  
Bacterial Membranes

Proline-rich antimicrobial peptides (PrAMPs) are cationic antimicrobial peptides unusual for their ability to penetrate bacterial membranes and kill cells without causing membrane permeabilization. Structural studies show that many such PrAMPs bind deep in the peptide exit channel of the ribosome, near the peptidyl transfer center. Biochemical studies of the particular synthetic PrAMP oncocin112 (Onc112) suggest that on reaching the cytoplasm, the peptide occupies its binding site prior to the transition from initiation to the elongation phase of translation, thus blocking further initiation events. We present a superresolution fluorescence microscopy study of the long-term effects of Onc112 on ribosome, elongation factor-Tu (EF-Tu), and DNA spatial distributions and diffusive properties in intact Escherichia coli cells. The new data corroborate earlier mechanistic inferences from studies in vitro. Comparisons with the diffusive behavior induced by the ribosome-binding antibiotics chloramphenicol and kasugamycin show how the specific location of each agent's ribosomal binding site affects the long-term distribution of ribosomal species between 30S and 50S subunits versus 70S polysomes. Analysis of the single-step displacements from ribosome and EF-Tu diffusive trajectories before and after Onc112 treatment suggests that the act of codon testing of noncognate ternary complexes (TCs) at the ribosomal A-site enhances the dissociation rate of such TCs from their L7/L12 tethers. Testing and rejection of noncognate TCs on a sub-ms timescale is essential to enable incorporation of the rare cognate amino acids into the growing peptide chain at a rate of ∼20 aa/s.

In vivo assessment of human vaginal oxygen and carbon dioxide levels during and post menses

2005 ◽  
Vol 99 (4) ◽  
pp. 1582-1591 ◽  
Author(s):  
Donna R. Hill ◽  
Marianne E. Brunner ◽  
Deborah C. Schmitz ◽  
Catherine C. Davis ◽  
Janine A. Flood ◽  
...  
Keyword(s):  
Animal Studies ◽  
Pathogenic Bacteria ◽  
Sensor Technology ◽  
Atmospheric Conditions ◽  
Bacterial Virulence Factor ◽  
Carbon Dioxide Levels ◽  
Kinetics Of ◽  
Insertion Process

Previous in vitro and in vivo animal studies showed that O2and CO2concentrations can affect virulence of pathogenic bacteria such as Staphylococcus aureus. The objective of this work was to measure O2and CO2levels in the vaginal environment during tampon wear using newly available sensor technology. Measurements by two vaginal sensors showed a decrease in vaginal O2levels after tampon insertion. These decreases were independent of the type of tampons used and the time of measurement (mid-cycle or during menstruation). These results are not in agreement with a previous study that concluded that oxygenation of the vaginal environment during tampon use occurred via delivery of a bolus of O2during the insertion process. Our measurements of gas levels in menses showed the presence of both O2and CO2in menses. The tampons inserted into the vagina contained O2and CO2levels consistent with atmospheric conditions. Over time during tampon use, levels of O2in the tampon decreased and levels of CO2increased. Tampon absorbent capacity, menses loading, and wear time influenced the kinetics of these changes. Colonization with S. aureus had no effect on the gas profiles during menstruation. Taken collectively, these findings have important implications on the current understanding of gaseous changes in the vaginal environment during menstruation and the potential role(s) they may play in affecting bacterial virulence factor production.

scholarly journals Ex VivoMaturation Assay for Testing Antimalarial Sensitivity of Rodent Malaria Parasites

2016 ◽  
Vol 60 (11) ◽  
pp. 6859-6866 ◽  
Author(s):  
Zi Wei Chang ◽  
Benoit Malleret ◽  
Bruce Russell ◽  
Laurent Rénia ◽  
Carla Claser
Keyword(s):  
Ex Vivo ◽  
Single Step ◽  
Parasite Development ◽  
Ring Stage ◽  
Malaria Parasites ◽  
Rodent Malaria ◽  
Content Type ◽  
Parasite Biology

ABSTRACTEx vivoassay systems provide a powerful approach to studying human malaria parasite biology and to testing antimalarials. For rodent malaria parasites, short-termin vitroculture andex vivoantimalarial susceptibility assays are relatively cumbersome, relying onin vivopassage for synchronization, since ring-stage parasites are an essential starting material. Here, we describe a new approach based on the enrichment of ring-stagePlasmodium berghei,P. yoelii, andP. vinckei vinckeiusing a single-step Percoll gradient. Importantly, we demonstrate that the enriched ring-stage parasites develop synchronously regardless of the parasite strain or species used. Using a flow cytometry assay with Hoechst and ethidium or MitoTracker dye, we show that parasite development is easily and rapidly monitored. Finally, we demonstrate that this approach can be used to screen antimalarial drugs.

scholarly journals Potencial de plantas acuáticas para la remoción de coliformes totales y Escherichia coli en aguas negras

Enfoque UTE ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 131-144
Author(s):  
R León ◽  
Beatriz Margarita Pernía Santos ◽  
Rosa Siguencia ◽  
S Franco ◽  
A Noboa ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Eichhornia Crassipes ◽  
Lemna Minor ◽  
Pistia Stratiotes ◽  
Azolla Caroliniana ◽  
E Coli

El objetivo de la investigación fue encontrar plantas acuáticas con potencial de remover E. coli y coliformes totales de agua contaminada. Para ello, se realizaron muestreos en Río Guayas, Recinto Aguas Frías y Estero Peñafiel, donde se seleccionaron las especies: Azolla caroliniana, Eichhornia crassipes, Pistia stratiotes, Salvinia auriculata y Lemna minor (Control positivo). Las plantas se reprodujeron in vitro y se realizaron bioensayos para verificar su capacidad de remover E. coli y coliformes. Los ensayos se realizaron por triplicado en 0,5 L de agua con fertilizante y se inoculó una cepa de referencia E. coli ATCC25922.  Como control negativo se inoculó la bacteria sin plantas y control positivo con la planta Lemna sp. Después de 7 días se determinó la carga bacteriana remanente. Se encontró un porcentaje de eliminación de E. coli de 99% para A. caroliniana, E. crassipes y Lemna sp. y de 100% para P. stratiotes y S. auriculata. Posteriormente, se realizaron ensayos con aguas negras en los cuales S. auriculata y A. caroliniana lograron el 100% de remoción de las coliformes y E. coli el resto de plantas tuvieron niveles menores de eficiencia. Se propone el uso de estas especies para el tratamiento de aguas contaminadas. 

scholarly journals Phytoremediation of Arsenic Contaminated Water Using Aquatic, Semi-Aquatic and Submerged Weeds

2021 ◽  
Author(s):  
Dibakar Roy ◽  
Dasari Sreekanth ◽  
Deepak Pawar ◽  
Himanshu Mahawar ◽  
Kamal K. Barman
Keyword(s):  
Membrane Filtration ◽  
Lemna Minor ◽  
Typha Latifolia ◽  
Contaminated Water ◽  
Aquatic Weed ◽  
Tolerance Mechanism ◽  
Removal Capacity ◽  
Weed Flora ◽  
The One ◽  
Co Precipitation

Arsenic (As) is the one the most toxic element present in earth which poses a serious threat to the environment and human health. Arsenic contamination of drinking water in South and Southeast Asia reported one of the most threatening problems that causes serious health hazard of millions of people of India and Bangladesh. Further, use of arsenic contaminated ground water for irrigation purpose causes entry of arsenic in food crops, especially in Rice and other vegetable crops. Currently various chemical technologies utilized for As removal from contaminated water like adsorption and co-precipitation using salts, activated charcoal, ion exchange, membrane filtration etc. are very costly and cannot be used for large scale for drinking and agriculture use. In contrast, phytoremediation utilizes green plats to remove pollutants from contaminated water using various mechanisms such as rhizofiltration, phytoextraction, phytostabilization, phytodegrartion and phytovolatilization. A large numbers of terrestrial and aquatic weed flora have been identified so far having hyper metal, metalloid and organic pollutant removal capacity. Among the terrestrial weed flora Arundo donax, Typha latifolia, Typha angustifolia, Vetivaria zizinoids etc. are the hyper As accumulator. Similarly Eicchornea crassipes (Water hyacinth), Pistia stratiotes (water lettuce), Lemna minor (duck weed), Hyrdilla verticillata, Ceratophyllum demersum, Spirodella polyrhiza, Azola, Wolfia spp., etc. are also capable to extract higher amount of arsenic from contaminated water. These weed flora having As tolerance mechanism in their system and thus remediate As contaminated water vis-à-vis continue their life cycle. In this chapter we will discuss about As extraction potential of various aquatic and semi aquatic weeds from contaminated water, their tolerance mechanism, future scope and their application in future world mitigating As contamination in water resources.

scholarly journals In vitro susceptibility studies and detection of vancomycin resistance genes in clinical isolates of enterococci in Nagasaki, Japan

1997 ◽  
Vol 119 (2) ◽  
pp. 175-181 ◽  
Author(s):  
Y. HIRAKATA ◽  
T. YAMAGUCHI ◽  
K. IZUMIKAWA ◽  
J. MATSUDA ◽  
K. TOMONO ◽  
...  
Keyword(s):  
Resistance Genes ◽  
Antimicrobial Agents ◽  
The United States ◽  
Vancomycin Resistance ◽  
Single Step ◽  
Clinical Isolates ◽  
Glycopeptide Resistance ◽  
In Vitro Susceptibility ◽  
Enterococcus Gallinarum

Glycopeptide resistance in enterococci is now a cause of clinical concern in the United States and Europe. However, details of vancomycin resistance in enterococci in Japan have been unknown. We measured minimum inhibitory concentrations (MICs) of various antimicrobial agents for a total of 218 clinical strains of enterococci isolated in our hospital in 1995–6 in addition to 15 strains with known genotypic markers of resistance. We also screened vancomycin resistance genes using a single step multiplex-PCR.In clinical isolates, only two strains of Enterococcus gallinarum were of intermediate resistance to vancomycin (MIC, 8 μg/ml), while the others were all susceptible. Glycopeptides (vancomycin and teicoplanin) and streptogramins (RP 58500 and RPR 106972) showed potent antimicrobial effects for the isolates. In addition, ampicillin was also potent for Enterococcus faecalis, while ampicillin, minocycline and gentamicin were potent for Enterococcus avium. No vanA or vanB genes were detected, while vanC1 and vanC23 genes were detected from two and four strains, respectively. Our results suggest that incidence of VRE in Japan may be estimated as still very low at this time.

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