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Single-walled carbon nanohorns (SWNHs) have been shown to be effective photothermal enhancers and drug delivery agents for potential cancer therapy, particularly for the eradication of bladder cancer lesions. In this study, the potential for SWNHs to serve as nanotheranostic vehicles is demonstrated through simultaneous delivery of the chemotherapeutic cisplatin from SWNH cone interiors and imaging of the nanoparticle transport to tumor cells using conjugated quantum dots (QDs). Following the formation of cisplatin-modified SWNH-QD (SWNH-QD + cis) hybrids, their characterization by scanning and transmission electron microscopy (STEM, TEM), energy dispersive spectroscopy (EDS), and dynamic light scattering (DLS) were performed to characterize the composite nanoparticles. Drug release profiles and 50% inhibitory concentration (IC50) determination showed that QDs do not hinder the therapeutic ability of SWNHs. In addition, the hybrids were trackable over the course of a 3 day period, which indicates that internalized SWNHs can continue to deliver therapy after removal of the nano-agents from the cell culture. This unique SWNH hybrid can successfully be used as an imaging agent to study nanoparticle transport and consequently the delivery of a therapeutic to the targeted cancer cells.

Multiwalled carbon nanotube-titanium dioxide (MWNT-TiO2) nanohybrids (NHs), a promising support for electrocatalysts, have a high likelihood of environmental release. Aggregation of these NHs may or may not be captured by the sum of their component behavior, thus necessitating a systematic evaluation. This study probes the “part-whole question” by systematically evaluating the role of TiO2 loading (C:Ti molar ratios of 1:0.1, 1:0.05 and 1:0.033) on the aggregation behavior of these NHs. Aggregation kinetics of these in-house synthesized (using a sol−gel method) NHs and the components is investigated with time-resolved dynamic light scattering in the presence of mono- and divalent cations and with and without Suwannee River humic acid. A deviation in the aggregation behavior from classical electrokinetic theory has been observed which indicates that the material complexity has a strong influence in the observed behavior; hence other material attributes (e.g., fractal dimension, surface roughness, charge heterogeneity, etc.) should be carefully considered when studying such materials. The sum of the aggregation behavior of the parts may not capture that of the whole (i.e., of the NHs); aggregation depends on the TiO2 loading and also on the hybridization process and the background aquatic chemistry.

Due to the position of microwave (MW) radiation in the electromagnetic spectrum, it has not yet been successfully utilized to inactivate waterborne microorganisms at a reasonable (energy) cost. Exceptional properties at the nano-scale, namely MW absorption-abilities of carbon nanotubes and excellent spectral conversion-capabilities of lanthanide series metal oxides in concert, hold promise to overcome the energetic barrier of this widely used and affordable technology. This study reports the synthesis of a nano-heterostructure that combines carbon nanotubes' and erbium oxide's properties to generate reactive oxygen species (ROS) and inactivate Pseudomonas aeruginosa. Detailed characterization of the synthesized nanohybrid (NH) material with electron microscopy, X-ray techniques, and thermal gravimetric analysis confirms effective hybridization. At least one log unit of microbial inactivation was achieved via ROS generation with only 20 s of MW irradiation at 110 W (0.0006 kW h energy use), using a conventional MW oven. Inactivation studies with ROS scavenger molecules prove that the generated oxygen species played the dominant role in bacterial inactivation. These breakthrough results hold promise to enable an unintended use (i.e., disinfection) of MW technology, which is diffused deep into the global societal fabric.

Highly surface active nano-scale materials, when released into the natural environment, tend to adsorb geo- and bio-macromolecules and end up presenting a modified interface to biological species. Capped nanocrystals and polymer/surfactant modified nanomaterials also are known to undergo ligand exchange when exposed to natural systems. Thus, nano-bio interactions will primarily be governed by the adsorbed or exchanged natural macromolecules. To-date there has been no established technique determining the kinetics of ligand exchange or characterizing the bound geo-biomacromolecular corona in an environmental setting. Single-molecule imaging utilizing near-infra red spectrometry, and single-molecule imaging of fluorophore-tagged polymeric ligands can enable detailed characterization of biopolymeric corona. This perspective aims to highlight the importance of ligand exchange, identify roles of surface ligands on nano-bio interaction, and present initial evidence of macromolecular characterization on nanotube surfaces using single-molecule techniques. This commentary also aims to outline the challenges facing nano-environmental health and safety community on assessing biological interaction with complex nano-scale heterostructures in a realistic environmental matrix.

Nanohybrids (NHs) with synergistic and emergent properties are used as electrocatalysts, photocatalysts, and antimicrobial agents in numerous applications. Carbon nanotube (CNT)–metal oxide NHs are one of the most commercialized heterostructures because of their advantages as catalyst supports in the fuel cell industry. To date, there has been little understanding of their environmental behavior, primarily due to the lack of a robust yet facile synthesis technique. This study presents an elegant synthesis method, which varies the reagent composition and ratio to grow metal oxides of choice onto multiwalled carbon nanotube (MWNT) surfaces. This technique can synthesize heterostructures with elements ranging from transition (Ti and Zn) to lanthanide series (Er and Pr) metals. This modified sol–gel method can provide large material yields (100s of mg) with a high degree of overall homogeneity between synthesized batches. Such a method for preparing complex NHs from component materials can be extremely useful to perform systematic environmental analyses.

Exposure to multi-walled carbon nanotubes (MWCNTs) is suspected to contribute to pulmonary fibrosis through modulation of transforming growth factor beta1 (TGF-β1). There is growing evidence that estrogen signaling is important in pulmonary function and modulates pro-fibrogenic signaling in multiple models of pulmonary fibrosis, however an interaction between MWCNT exposure and estrogen signaling in the lung is not known. The purpose of this work was to determine whether estrogen signaling in the lung is a target for MWCNTs and to identify potential signaling mechanisms mediating MWCNT-induced responses using a whole-body inhalation mouse model and an in vitro human lung cell model. Mice exposed to MWCNTs had reduced mRNA expression of estrogen receptor alpha and beta (Esr1 and Esr2, respectively) in lung tissue at multiple time-points post-exposure, whereas expression of g-protein coupled estrogen receptor1 (Gper1) was more variable. We localized ESR1 protein expression as primarily associated with bronchioles and within inflammatory macrophages. The reduction in estrogen receptor expression was concomitant to an increase in TGF-β1 levels in the bronchoalveolar lavage fluid (BALF) of MWCNT-exposed animals. We confirmed a role for TGF-β1 in mediating MWCNT-induced repression of ESR1 mRNA expression using a TGF-β type-I receptor inhibitor in bronchial epithelial cells in vitro. Overall these results highlight a novel mechanism of MWCNT-induced signaling where MWCNT-induced regulation of TGF-β1 represses estrogen receptor expression. Dysregulated estrogen signaling through altered receptor expression may have potential consequences on lung function.

The aggregation kinetics of nC60 and higher-order fullerene (HOF) clusters, i.e., nC70, nC76, and nC84, was systematically studied under a wide range of mono- (NaCl) and divalent (CaCl2) electrolytes and using time-resolved dynamic light scattering. Suwanee River Humic Acid (SRHA) was also used to determine the effect of natural macromolecules on nHOF aggregation. An increase in electrolyte concentration resulted in electrical double-layer compression of the negatively charged fullerene clusters, and the nC60s and nHOFs alike displayed classical Derjaguin-Landau-Verwey-Overbeek (DLVO) type interaction. The critical coagulation concentration (CCC) displayed a strong negative correlation with the carbon number in fullerenes and was estimated as 220, 150, 100, and 70 mM NaCl and 10, 12, 6, and 7.5 mM CaCl2 for nC60, nC70, nC76, and nC84, respectively. The aggregation mechanism (i.e., van der Waals interaction domination) was enumerated via molecular dynamics simulation and modified DLVO model. The presence of SRHA (2.5 mg TOC/L) profoundly influenced the aggregation behavior by stabilizing all fullerene clusters, even at a 100 mM NaCl concentration. The results from this study can be utilized to predict aggregation kinetics of nHOF clusters other than the ones studied here. The scaling factor for van der Waals interaction can also be used to model nHOF cluster interaction.

Several studies have investigated the use of nanomaterials to modify asphalt binders and achieve improved properties. It is possible that in some cases nanomaterials do not disperse and agg...

Carbon nanotubes are hybridized with metal crystals to impart multifunctionality into the nanohybrids (NHs). Simple but effective synthesis techniques are desired to form both zero-valent and oxides of different metal species on carbon nanotube surfaces. Sol-gel technique brings in significant advantages and is a viable technique for such synthesis. This study probes the efficacy of sol-gel process and aims to identify underlying mechanisms of crystal formation. Standard electron potential (SEP) is used as a guiding parameter to choose the metal species; i.e., highly negative SEP (e.g., Zn) with oxide crystal tendency, highly positive SEP (e.g., Ag) with zero-valent crystal-tendency, and intermediate range SEP (e.g., Cu) to probe the oxidation tendency in crystal formation are chosen. Transmission electron microscopy and X-ray diffraction are used to evaluate the synthesized NHs. Results indicate that SEP can be a reliable guide for the resulting crystalline phase of a certain metal species, particularly when the magnitude of this parameter is relatively high. However, for intermediate range SEP-metals, mix phase crystals can be expected. For example, Cu will form Cu2O and zero-valent Cu crystals, unless the synthesis is performed in a reducing environment.

Background Numerous toxicological studies have focused on injury caused by exposure to single types of nanoparticles, but few have investigated how such exposures impact a host’s immune response to pathogen challenge. Few studies have shown that nanoparticles can alter a host’s response to pathogens (chiefly bacteria) but there is even less knowledge of the impact of such particles on viral infections. In this study, we performed experiments to investigate if exposure of mice to single-walled carbon nanotubes (SWCNT) alters immune mechanisms and viral titers following subsequent influenza A virus (IAV) infection. Methods Male C57BL/6 mice were exposed to 20 μg of SWCNT or control vehicle by intratracheal instillation followed by intranasal exposure to 3.2 × 104 TCID50 IAV or PBS after 3 days. On day 7 mice were euthanized and near-infrared fluorescence (NIRF) imaging was used to track SWCNT in lung tissues. Viral titers, histopathology, and mRNA expression of antiviral and inflammatory genes were measured in lung tissue. Differential cell counts and cytokine levels were quantified in bronchoalveolar lavage fluid (BALF). Results Viral titers showed a 63-fold increase in IAV in SWCNT + IAV exposed lungs compared to the IAV only exposure. Quantitation of immune cells in BALF indicated an increase of neutrophils in the IAV group and a mixed profile of lymphocytes and neutrophils in SWCNT + IAV treated mice. NIRF indicated SWCNT remained in the lung throughout the experiment and localized in the junctions of terminal bronchioles, alveolar ducts, and surrounding alveoli. The dual exposure exacerbated pulmonary inflammation and tissue lesions compared to SWCNT or IAV single exposures. IAV exposure increased several cytokine and chemokine levels in BALF, but greater levels of IL-4, IL-12 (P70), IP-10, MIP-1, MIP-1α, MIP-1β, and RANTES were evident in the SWCNT + IAV group. The expression of tlr3, ifnβ1, rantes, ifit2, ifit3, and il8 was induced by IAV alone but several anti-viral targets showed a repressed trend (ifits) with pre-exposure to SWCNT. Conclusions These findings reveal a pronounced effect of SWCNT on IAV infection in vivo as evidenced by exacerbated lung injury, increased viral titers and several cytokines/chemokines levels, and reduction of anti-viral gene expression. These results imply that SWCNT can increase susceptibility to respiratory viral infections as a novel mechanism of toxicity. Electronic supplementary material The online version of this article (10.1186/s12985-017-0909-z) contains supplementary material, which is available to authorized users.

Aromatic rice (Oryza sativa L.) cultivars are strong aromatic rice cultivars which can thrive well in rice fields prone to flood, drought and other soil constraints. The present investigation was undertaken to determine a suitable media compositions for callus induction and regeneration using immature embryo of six aromatic grown rice cultivars of Bangladesh, namely, Chinigura, Kalijira, Radhuni Pagal, Modhumala, Kataribog and Mohonbhog. For callus induction different concentrations and combinations of 2, 4-Dichlorophenoxyaceticacid (2, 4-D) along with NAA were evaluated. Maximum callus induction (97.22%) was observed in Kalijira when 2 mg/L of 2, 4-D and 0.5 mg/l NAA was used and less Modhumala (66.67%) and remaining cultivars showed moderate. For regeneration initially different concentrations and combinations of 6-BenzylAminoPurine (BAP) and Indole-3-Acetic Acid (IBA) were tested. Maximum regeneration frequency (91.67%) was observed Kalijira when the optimum concentrations and combinations of 0.5 mg/l of BAP + 0.1 of mg/l IBA were used. Presently optimized regeneration method holds promise for facilitating the deployment of agronomical important trait through genetic transformation for the improvement of this important food crops.DOI: http://dx.doi.org/10.3126/ijasbt.v2i2.10313Int J Appl Sci Biotechnol, Vol. 2(2): 160-167

Bungarus caeruleus or common Indian krait is a member of the venomous big four snake species. Its venom contains a neurotoxic protein alpha-delta-bungarotoxin-4 and is found to be responsible for human death 4-8 hours after the snake bite. Antigenecity of this protein was determined by Hopp & Woods and Kolaskar & Tangaonkar method. We predicted MHC class I and MHC class II binding peptides of antigenic protein from alpha-delta-bungarotoxin-4 which are important determinant for protection of host from snake bite. Fragments selected through this study revealed higher efficiency binders. As a result, higher percentages of their atoms are directly involved in binding in comparison with larger molecules. These potential fragments, therefore can be a novel tool in the arena of cross protection to develop host specific antibodies in different objectives. We operated AllerHunter for predicting allergenicity based on the structural and physiochemical properties of whole alpha-delta-bungarotoin-4 and it was found to be non-allergen. The potential epitopes of alpha-delta-bungarotoxin-4 were found to be located at sequences “GENLCYTKM” and “FCSSRGKVI” and these were found to be sufficient for eliciting the desired immune response. In this study a hypothetical immunization is developed which demands more validation and study. It can be emphasized that such predictive in silico study requires an in vivo experiments comprehensibly which must be assured to validate such approaches. So our goal was to identify a conformationally biased epitope sequence which aims to provide a new paradigm to design epitope based peptide vaccines in order to alleviate immunological infections from Krait neurotoxin. Key words: Bungarus caeruleus, alpha-delta-bungarotoxin-4, bungarotoxin, peptide vaccine, antigen protein, nonamers.

Recent evidence suggests that, because of their sorptive nature, if single-walled carbon nanotubes (SWCNTs) make their way into aquatic environments, they may reduce the toxicity of other waterborne contaminants. However, few studies have examined whether contaminants remain adsorbed following ingestion by aquatic organisms. The objective of this study was to examine the bioavailability and bioactivity of ethinyl estradiol (EE2) sorbed onto SWCNTs in a fish gastrointestinal (GI) tract. Sorption experiments indicated that SWCNTs effectively adsorbed EE2, but the chemical was still able to bind and activate soluble estrogen receptors (ERs) in vitro. However, centrifugation to remove SWCNTs and adsorbed EE2 significantly reduced ER activity compared to that of EE2 alone. Additionally, the presence of SWCNTs did not reduce the extent of EE2-driven induction of vitellogenin 1 in vivo compared to the levels in organisms exposed to EE2 alone. These results suggest that while SWCNTs adsorb EE2 from aqueous solutions, under biological conditions EE2 can desorb and retain bioactivity. Additional results indicate that interactions with gastrointestinal proteins may decrease the level of adsorption of estrogen to SWCNTs by 5%. This study presents valuable data for elucidating how SWCNTs interact with chemicals that are already present in our aquatic environments, which is essential for determining their potential health risk.

Background In the present study, we investigated the arsenic accumulation in different parts of rice irrigated with arsenic contaminated water. Besides, we also evaluated the protective effects of Corchorus olitorius leaves against arsenic contaminated rice induced toxicities in animal model. Methods A pot experiment was conducted with arsenic amended irrigation water (0.0, 25.0, 50.0 and 75.0 mg/L As) to investigate the arsenic accumulation in different parts of rice. In order to evaluate the protective effects of Corchorus olitorius leaves, twenty Wistar albino rats were divided into four different groups. The control group (Group-I) was supplied with normal laboratory pellets while groups II, III, and IV received normal laboratory pellets supplemented with arsenic contaminated rice, C. olitorius leaf powder (4 %), arsenic contaminated rice plus C. olitorius leaf powder (4 %) respectively. Different haematological parameters and serum indices were analyzed to evaluate the protective effects of Corchorus olitorius leaves against arsenic intoxication. To gather more supportive evidences of Corchorus olitorius potentiality against arsenic intoxication, histopathological analysis of liver, kidney, spleen and heart tissues was also performed. Results From the pot experiment, we have found a significant (p ≤ 0.05) increase of arsenic accumulation in different parts of rice with the increase of arsenic concentrations in irrigation water and the trend of accumulation was found as root > straw > husk > grain. Another part of the experiment revealed that supplementation of C. olitorius leaves with arsenic contaminated rice significantly (p

Face Recognition is one of the most popular and powerful method of identification of the Face Recognition Systems. The identification is very important to identify the Images, Video, Graphics and Blurred and Noisy Images, Video and Graphics. Face identification has received substantial attention from researchers in face recognition, pattern recognition, biometrics, computer vision, and communities. Because of the increased attention being devoted to authentication, man machine communication, content-based image retrieval, and image coding. The problem of face identification of blurred and noisy images by relative motion between the camera and the object scene is important in a large number of applications. The solution is modified facial deblur inference (FADEIN) proposed algorithm here identifies important feature (face detection and face recognition) with which to characterize the point spread function (PSF) of the blur. The identification method is based on the concept that image characteristics along the direction and parameter motion. These are different from the characteristics in other directions. According to the PSF shape, the homogeneity and the smoothness of the blurred image in the motion direction are greater than in other directions. By registering the blurred and noisy images, we emphasize the PSF characteristics at the expense of the image characteristics. Identifies the direction and extent PSF of the blur, and evaluates its shapes. Which depends on the type of motion during the exposure. Correct Identification of the PSF feature permits better performance and accuracy of the blurred image. And compare eye, mouth, and face boundary maps to verify each face candidate. The resulting facial deblur inference model is visually similar to the store face, and proves to be quite useful for recognizing non-frontal views based on an appearance based recognition algorithm. Modified algorithm is very useful to identify the blurred and noisy images. This paper is proposed a novel method to identify the Face Recognition with the help of matching feature (point of the identification) of the current images compared to the stored images. This method is enhancing the performance and accuracy of the face recognition algorithm. Proposed algorithms are improving the face recognition rate 97.4% and also enhance the accuracy. This proposed algorithm is used for both blurred and noisy image. Proposed algorithm is very useful in identification of the faces (Criminal and other unauthorized person).

Porous media transport of engineered nanomaterials (ENMs) is typically assessed in a controlled single-particulate environment. Presence of a secondary particle (either natural or engineered) in the natural environment though likely, is rarely taken into consideration in assessing ENMs' transport behavior. This study systematically assesses the effect of a secondary ENM (i.e., pluronic acid modified single-walled carbon nanotubes, PA-SWNTs) on a primary particle (i.e., gold nanospheres, AuNSs) transport through saturated porous media under a wide range of aquatic conditions (1–100 mM NaCl). AuNS hetero-dispersions (i.e., with PA-SWNTs) are transported through saturated sand columns, and the transport behavior is compared to AuNS-only homo-dispersion cases, which display classical ionic strength-dependent behavior. AuNS hetero-dispersion, however, is highly mobile with little to no ionic strength-dependent effects. This study also assesses the role of pre-coating of the collectors with PA-SWNTs on AuNSs' mobility, thereby elucidating the role played by the order of introduction of the secondary particles. Pre-existence of the secondary particles in the porous media shows enhanced filtration of primary AuNSs. However, the presence of natural organic matter (NOM) slightly increases AuNS mobility through PA-SWNT coated sand at 10 mM ionic strength. The study results demonstrate that the presence and order of addition of the secondary particles strongly influence primary particles' mobility. Thus ENMs can demonstrate facilitated transport or enhanced removal, depending on the presence of the secondary particulate matter and background solution chemistry.

Plausible interactions between food contaminants and natural constituents in vivo and protective effect of polyphenols present in I. aquatica against carbofuran toxicity in Charles Foster rats were evaluated. Determinations based on antioxidant enzyme activities showed significant alterations in glutathione, glutathione peroxidase, superoxide dismutase and catalase in tissues (liver and brain) and plasma of pesticide treated group while polyphenolic extracts from I. aquatica (IAE) attenuated their activities when given alongwith carbofuran. IAE decreased enhanced lipid peroxidation levels in plasma and erythrocyte membrane and cholesterol levels in brain and plasma. IAE also minimized histopathological degenerative changes produced by carbofuran. While single cell gel electrophoresis showed that secondary metabolites in leafy vegetables produced a combinatorial effect with pesticide at cellular level, DNA fragmentation level in bone marrow cells showed a decline in the IAE treated rats. Food safety adversely affected by various chemical contaminants can be retained by plant polyphenols and secondary plant constituents that can be found together in bolus. Therefore, the present study gives an insight into the protective role of naturally found polyphenols against pesticide toxicity.

Engineered nanomaterials (ENMs) are mostly synthesized with modified surfaces using various surfactants, polymeric, or biomolecule coatings to achieve desired functionality. When exposed to the environment, coatings on the ENMs will undergo the first set of interactions with natural geo- and bio-macromolecules pre-existing in aqueous and/or soil matrices. Such interfacial interaction will likely alter the conformation and extent of coverage of the synthetic ENM surface coatings via exchange, displacement, and/or overcoating by environmental macromolecules. The exchange kinetics and extent of replacement of the synthetic coatings will profoundly impact environmental fate, transport, transformation, and toxicity of the ENMs. This chapter discusses the state-of-the-art literature to identify key synthetic coating types, their interaction with the environmental and biological macromolecules, and illustrate the existing challenges to determine coating exchange kinetics and its environmental implications on ENMs.

All mouse weight during 7-day experiment in grams (Mean ± SD). S1B. All mouse weight loss during 7-day experiment as % change from day 0 (Mean ± SD). Table S2. Primer sets used in this study. Figure. S1. Characterization of SWCNT. Hydrodynamic radii plot of SG65i dialyzed SWCNT used in all experiments. All experiments were performed at 37 oC. Figure S2. NIRF of lung tissues among animals in control and IAV only group. Mouse lung H&E stained tissue sections from a (A) control and (B) IAV exposed animal and corresponding NIRF image, 400X. (PDF 879 kb)

All mouse weight during 7-day experiment in grams (Mean ± SD). S1B. All mouse weight loss during 7-day experiment as % change from day 0 (Mean ± SD). Table S2. Primer sets used in this study. Figure. S1. Characterization of SWCNT. Hydrodynamic radii plot of SG65i dialyzed SWCNT used in all experiments. All experiments were performed at 37 oC. Figure S2. NIRF of lung tissues among animals in control and IAV only group. Mouse lung H&E stained tissue sections from a (A) control and (B) IAV exposed animal and corresponding NIRF image, 400X. (PDF 879 kb)