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The influence of exposing carcinoma cells to a static magnetic field (SMF) and low-intensity pulsed ultrasound (LIPUS), for different durations (15–45 min/d), in the presence of magnetic and non-magnetic drug carriers, on their in vitro inhibition is examined. Increasing the exposure time by 15 min/d decreased the culture duration by 24 h to achieve the same level of inhibition in colon (HCT116) and hepatocellular (HepG2) cells. Cell cycle analysis revealed enhanced cellular blockage in G1 and S phases with SMF + LIPUS exposure, and exposure for 45 min/d completely suppressed the S → G2 transition. Apoptosis of both types of cells increased with SMF + LIPUS treatment time, and HepG2 cells exhibited elevated necrosis with >30 min/d exposure. HepG2 cells also had higher amounts of reactive oxygen species (seven- to eightfold) than HCT116 cells (two- to sixfold), suggesting treatment effectiveness is cell and drug carrier dependent. The accelerated cellular activities are attributed to the enhanced internalization of drug carriers as a consequence of destabilized cellular membranes caused by the SMF + LIPUS-generated mechanical and electrical stimuli.

Macrophages can associate with extracellular matrix (ECM) demonstrating nanosequenced cell-adhesive RGD ligand. In this study, we devised barcoded materials composed of RGD-coated gold and RGD-absent iron nanopatches to show various frequencies and position of RGD-coated nanopatches with similar areas of iron and RGD-gold nanopatches that maintain macroscale and nanoscale RGD density invariant. Iron patches were used for substrate coupling. Both large (low frequency) and externally positioned RGD-coated nanopatches stimulated robust attachment in macrophages, compared with small (high frequency) and internally positioned RGD-coated nanopatches, respectively, which mediate their regenerative/anti-inflammatory M2 polarization. The nanobarcodes exhibited stability in vivo. We shed light into designing ligand-engineered nanostructures in an external position to facilitate host cell attachment, thereby eliciting regenerative host responses.

Developing materials with remote controllability of macroscale ligand presentation can mimic extracellular matrix (ECM) remodeling to regulate cellular adhesion in vivo. Herein, we designed charged mobile nanoligands with superparamagnetic nanomaterials amine-functionalized and conjugated with polyethylene glycol linker and negatively charged RGD ligand. We coupled negatively a charged nanoligand to a positively charged substrate by optimizing electrostatic interactions to allow reversible planar movement. We demonstrate the imaging of both macroscale and in situ nanoscale nanoligand movement by magnetically attracting charged nanoligand to manipulate macroscale ligand density. We show that in situ magnetic control of attracting charged nanoligand facilitates stem cell adhesion, both in vitro and in vivo, with reversible control. Furthermore, we unravel that in situ magnetic attraction of charged nanoligand stimulates mechanosensing-mediated differentiation of stem cells. This remote controllability of ECM-mimicking reversible ligand variations is promising for regulating diverse reparative cellular processes in vivo.

The native extracellular matrix (ECM) can exhibit heterogeneous nano-sequences periodically displaying ligands to regulate complex cell-material interactions in vivo. Herein, an ECM-emulating heterogeneous barcoding system, including ligand-bearing Au and ligand-free Fe nano-segments, is developed to independently present tunable frequency and sequences in nano-segments of cell-adhesive RGD ligand. Specifically, similar exposed surface areas of total Fe and Au nano-segments are designed. Fe segments are used for substrate coupling of nanobarcodes and as ligand-free nano-segments and Au segments for ligand coating while maintaining both nanoscale (local) and macroscale (total) ligand density constant in all groups. Low nano-ligand frequency in the same sequences and terminally sequenced nano-ligands at the same frequency independently facilitate focal adhesion and mechanosensing of stem cells, which are collectively effective both in vitro and in vivo, thereby inducing stem cell differentiation. The Fe/RGD-Au nanobarcode implants exhibit high stability and no local and systemic toxicity in various tissues and organs in vivo. This work sheds novel insight into designing biomaterials with heterogeneous nano-ligand sequences at terminal sides and/or low frequency to facilitate cellular adhesion. Tuning the electrodeposition conditions can allow synthesis of unlimited combinations of ligand nano-sequences and frequencies, magnetic elements, and bioactive ligands to remotely regulate numerous host cells in vivo.

In vitro bioactivity and bone mineralization of bioactive glass (BAG)-based composites reinforced with bismuth ferrite (BF) was assessed under 350 mT magnetic field exposure to demonstrate the positive influence of charge generating capacity of BF in accelerating bone like-apatite deposition and cellular activities. In vitro bioactivity studies, carried out in simulated body fluids, revealed increased apatite formation on the composites’ surface under magnetic field. The bone cell differentiation and mineralization activity of mouse preosteoblast cell line (MC3T3) on these composite surfaces were evaluated under magnetic field (30 min/day) using Alkaline Phosphatase Assay (ALP), Alizarin Red S and von Kossa Assay. The presence of BF combined with BAG matrix synergistically promoted spontaneous osteoblastic differentiation of MC3T3 cells after 14 days and enhanced calcium and phosphate mineralization after 21 days under 350 mT magnetic field treatment. The osteoblastic response in terms of ALP activity and bone-like mineralization was significantly high in 2 wt.% BF composites compared to pure BAG with magnetic treatment. BAG-2BF composites exhibited 2-fold and 3-fold higher ALP activity after 7 days and 14 days, respectively, than pure BAG. These results demonstrate the application prospects of BF reinforced BAG composites as scaffold for cellular support with enhanced bone tissue formation and accelerated osseointegration under magnetic field exposure.

Nowadays, tumor hypoxia has become a more predominant problem for diagnosis as well as treatment of cancer due to difficulties in delivering chemotherapeutic drugs and their carriers to these regions with reduced vasculature and oxygen supply. In such cases, external physical stimulus-mediated drug delivery, such as ultrasound and magnetic fields, would be effective. In this work, the effect of simultaneous exposure of low-intensity pulsed ultrasound and static magnetic field on colon (HCT116) and hepatocellular (HepG2) carcinoma cell inhibition was assessed in vitro. The treatment, in the presence of anticancer drug, with and without magnetic carrier, significantly increased the reactive oxygen species production and hyperpolarized the cancer cells. As a result, a significant increase in cell inhibition, up to 86%, was observed compared to 50% inhibition with bare anticancer drug. The treatment appears to have relatively more effect on HepG2 cells during the initial 24 h than on HCT116 cells. The proposed treatment was also found to reduce cancer cell necrosis and did not show any inhibitory effect on healthy cells (MC3T3). Our in vitro results suggest that this approach has strong application potential to treat cancer at lower drug dosage to achieve similar inhibition and can reduce health risks associated with drugs.

Drug delivery systems (DDSs) have been developed to target tumor cells by releasing active biomolecules at the specific site of infection, thus eliminating the side effects of anticancer drugs. However, DDSs are generally limited by high drug dosage, biobarriers, poor target recognition, etc. To address these deficiencies, we propose a new noninvasive method consisting of exposing the cancer cells to a combination of low-intensity pulsed ultrasound (LIPUS) and static magnetic field (SMF). This combined treatment found to negatively regulate colon cancer cell (HCT116) activities in vitro by altering their cell membrane potential and permeability thus increased the DDS efficacy by 40%. The treated cancer cell membrane became hyperpolarized leading to cancer cell death. The combination treatment (LIPUS + SMF) restricted the cancer cell proliferation to 16 and 5% in the presence of bare anticancer drug and DDS, respectively, in 72 h, which is almost 40% higher than that observed without the treatment. The acceleration of cancer cellular inhibition was confirmed by the significant increase in the apoptosis of the cell exposed to the LIPUS + SMF treatment. The observed improvement is believed to be due to changes in the cell membrane stability/permeability as a result of mechanical (20–22 kPa) and electrical (19–23 µV/cm) stimuli generated during the LIPUS + SMF treatment.

Systematic investigation was performed to identify any physicochemical property change of rare earth (RE) beta-diketonate precursor due to prolonged exposure to successive heating cycles. It is evident from the obtained results that the physical characteristics change rapidly in proportion to the thermal exposures which may lead to decomposition of the heated sample at much lower temperature than that of fresh sample. The observations further indicate, this RE chelate compound can be used satisfactorily as bulk precursor in vapor phase doping (VPD) process for up to five consecutive production cycles following which the sublimator needs to be refilled with fresh charge to maintain process reproducibility. It is also important to achieve the targeted specifications of laser/amplifier fiber preforms. According to our knowledge, this is the first ever study to identify any physicochemical behavioral change of RE precursor due to the thermal history as well as aging which would otherwise affect the performance of MCVD-VPD process. (C) 2017 The Electrochemical Society. All rights reserved.

A better understanding of how dynamics of physical and chemical changes occur during vermicomposting process would be helpful for determining the stability and maturity of vermicompost. For improving the knowledge about this issue several instrumental techniques were used in the present study to analyse the physical and chemical changes as a function of vermicomposting time of banana stem waste (BS) spiked with cow dung (CD) in different proportions using earthworm Eisenia fetida. Chemical analysis by ICP-AES showed gradual increase in the plant nutrients (P, Ca, K, Mg, Fe) up to 60 day of vermicomposting in all the treatments. But among different treatments, K, Mg and Fe were considerably higher in the BS2CD1 blend. The FTIR showed strong N O stretching vibration with increasing BS content signifying the presence of nitrate in the final compost. The TG analysis of final BS-CD composts described the lower mass loss (52–55%) in the final compared to the initial stage due to high level of humification by earthworms. The maturity of the final compost was confirmed by DSC analysis which exhibited lowering of relative intensity of exothermic peaks related to the easily degradable material at 320–330 °C and complex organic moieties at 495–530 °C. Decrease in the humification index (Q4/6, Q2/4, Q2/6) at 60 day confirmed the stability of vermicomposts. All the treatments showed 70% germination indices (GI) for rice and pea seeds. These findings defined a clear comparison between the treatments during vermicomposting in terms of stability and maturity and revealed that BS2CD1 can be utilized as nutrient-rich stable compost for enhanced crop production.

Self-setting calcium sulphate hemihydrate (CSH) composites were prepared by reinforcing with BiFeO3 (BF, a multiferroic material) with an aim to induce in situ charge generating capacity and increase its strength. CSH-BF composites (0–15 wt% BF), prepared by ball-milling, were evaluated in terms of setting and injectability, compressive strength, in vitro degradation, electrical/magnetic properties. Compressive strength of CSH-BF composites increased with BF concentration and up to 3-fold increase was observed compared to pure-CSH. Injectability and setting time of these composites were comparable to that of standard bone cements. In vitro degradation studies revealed ~27–33% degradation with good apatite precipitation on these composites. Remanant polarization of these composites varied between 0.056 and 0.251 μC/cm2. The composites with BF ≤ 5 wt% exhibited 200–375% increase in the cell viability with 200mT magnetic treatment. Osteoblast differentiation experiments showed high and rapid production of Alkaline Phosphatase followed by accelerated bone mineralization on the composites compared to pure-CSH. Electrical stimuli (remanant polarization) and its coupling during magnetic field treatment are responsible for enhanced bone-cell differentiation and mineralization on CSH-BF composites. Our results show that BF reinforcement of CSH not only improves its strength but also impart charge generating capacity, which can be effectively utilized to accelerate tissue healing or regeneration. Keywords: Calcium sulphate hemihydrate, Bismuth ferrite, Bone cement, Biocomposites, In vitro, Polarization, Mineralization, Alkaline phosphatase

Nowadays controlling cellular responses and function of biological molecules is becoming one of the prime areas of focus in biomedical field. In this investigation, an attempt is made to generate in situ charge in bioactive glass (BAG) by incorporating BiFeO3 (BF, a multiferroic material). It is hypothesized that BF in BAG can accelerate cellular activities for rapid tissue healing with externally applied magnetic field due to in situ polarization. BAG composites with different amounts of BF (2 to 15 wt%) are prepared using ball milling followed by pressing and sintering. The composites are characterized in terms of microstructures, constituent phases, magnetic, and electrical properties. Further, in vitro cytotoxicity studies are performed to evaluate the influence of in situ polarization by culturing mouse preosteoblast cells (MC3T3) on BAG-BF composites under different external magnetic field treatments. These in vitro cell-materials interaction studies demonstrate that magnetic field strengths of 200 or 350 mT exposed for 30 min/day can enhance cell viability and proliferation on these composites up to three times. Hence, the authors expect that this investigation will enable further developments to extend the application of multiferroics in bone tissue engineering.

Molecular identification of the Phytophthora spp. affecting betelvine (Piper betel), brinjal (Solanum melongena), guava (Psidium guajava), roselle (Hibiscus subdariffa), black pepper (Piper nigrum), sesame (Sesamum indicum), taro (Colocasia esculenta), chilli (Capsicum annuum), pointed gourd (Trichosanthes dioica), papaya (Carica papaya) was performed through rDNA ITS-RFLP and also additionally by sequencing the Internal Transcriber spacer (ITS) ITS1 and ITS2 regions. Phytophthora nicotianae, Phytophthora capsici, Phytophthora colocasiae, Phytophthora melonis and Phytophthora palmivora isolates from these 10 different crops were accessioned and the ITS sequences were deposited in Genbank. ITS sequences for Phytophthora isolates from most of these crops are being reported here for the first time. In this study, a review of all earlier Indian reports based on morphology from the above crops and their molecular corroboration has been attempted. This study revealed that not only is P. nicotianae the most prevalent species but also there is the presence of both P. nicotianae and P. capsici, but not P. palmivora on betelvine; as well as possible first reports of P. nicotianae on pepper, P. capsici on chilli and P. palmivora on papaya from this vegetable growing Eastern region of the country. Mating type assays and RAPD markers were used to assess the genotypic diversity of the population. This detection of diversity is a first and critical step for helping to devise and adopt strategies for control and quarantine of these pathogens in this region.