Modulation of calcium-influx by carboxymethyl tamarind­gold nanoparticles promotes biomineralization for tissue regeneration.

Gold nanoparticles (AuNPs) have been reported to modulate bone tissue regeneration and are being extensively utilized in biomedical implementations attributable to their low cytotoxicity, biocompatibility and simplicity of functionalization. Lately, biologically synthesized nanoparticles have acquired popularity because of their environmentally acceptable alternatives for diverse applications. Here we report the green synthesis of AuNPs by taking the biopolymer Carboxymethyl Tamarind (CMT) as a unique reducing as well as a stabilizing agent. The synthesized CMT-AuNPs were analyzed by UV-vis spectrophotometer, DLS, FTIR, XRD, TGA, SEM and TEM. These results suggest that CMT-AuNPs possess an average size of 19.93 ± 8.52 nm and have long-term stability. Further, these CMT-AuNPs promote the proliferation together with the differentiation and mineralization of osteoblast cells in a "dose-dependent" manner. Additionally, CMT-AuNPs are non-toxic to SD rats when applied externally. We suggest that the CMT-AuNPs have the potential to be a suitable and non-toxic agent for differentiation and mineralization of osteoblast cells in vitro and this can be tested in vivo as well.

Palladium Nanocapsules for Photothermal Therapy in the Near-Infrared II Biological Window.

Recent developments in nanomaterials with programmable optical responses and their capacity to modulate the photothermal effect induced by an extrinsic source of light have elevated plasmonic photothermal therapy (PPTT) to the status of a favored treatment for a variety of malignancies. However, the low penetration depth of near-infrared-I (NIR-I) lights and the need to expose the human body to a high laser power density in PPTT have restricted its clinical translation for cancer therapy. Most nanostructures reported to date exhibit limited performance due to (i) activity only in the NIR-I region, (ii) the use of intense laser, (iii) need of large concentration of nanomaterials, or (iv) prolonged exposure times to achieve the optimal hyperthermia state for cancer phototherapy. To overcome these shortcomings in plasmonic nanomaterials, we report a bimetallic palladium nanocapsule (Pd Ncap)─with a solid gold bead as its core and a thin, perforated palladium shell─with extinction both in the NIR-I as well as the NIR-II region for PPTT applications toward cancer therapy. The Pd Ncap demonstrated exceptional photothermal stability with a photothermal conversion efficiency of ∼49% at the NIR-II (1064 nm) wavelength region at a very low laser power density of 0.5 W/cm2. The nanocapsules were further surface-functionalized with Herceptin (Pd Ncap-Her) to target the breast cancer cell line SK-BR-3 and exploited for in vitro PPTT applications using NIR-II light. Pd Ncap-Her caused more than 98% cell death at a concentration of just 50 µg/mL and a laser power density of 0.5 W/cm2 with an output power of only 100 mW. Flow cytometric and microscopic analyses revealed that Pd Ncap-Her-induced apoptosis in the treated cancer cells during PPTT. Additionally, Pd Ncaps were found to have reactive oxygen species (ROS) scavenging ability, which can potentially reduce the damage to cells or tissues from ROS produced during PPTT. Also, Pd Ncap demonstrated excellent in vivo biocompatibility and was highly efficient in photothermally ablating tumors in mice. With a high photothermal conversion and killing efficiency at very low nanoparticle concentrations and laser power densities, the current nanostructure can operate as an effective phototherapeutic agent for the treatment of different cancers with ROS-protecting ability.

Formulation of a dual drug-loaded nanoparticulate co-delivery hydrogel system and its validation in rheumatoid arthritis animal model.

Rheumatoid arthritis (RA), a systemic autoimmune disease that dramatically affects patients' quality of life. Given the intricacy of RA's pathophysiology, no single treatment can completely halt the disease progression. Here, we attempted to treat RA holistically and synergistically by co-delivering methotrexate (MTX), a standard slow-acting anti-rheumatic drug, and phenethyl isothiocyanate (PEITC), a bioactive phytochemical, using a sodium alginate (SA)-pluronic F127 (PF-127) in situ hydrogel formulation. Therefore, in the current study, the co-delivery of MTX and PEITC in the nanoparticulate form could help enhance stability and solubility and facilitate greater penetration in the target arthritic tissues. The fabricated MTX NP and PEITC NE were found to have a minimum particle size, PDI, and good zeta potential. Results from in vitro release studies showed that MTX and PEITC were simultaneously released from the DD NP HG matrix over 6-7 days through diffusion and erosion mechanisms. An intra-articular (IA) injection of DD NP HG dramatically reduced chronic inflammation in adjuvant-induced arthritis (AIA) rats, delayed the onset of bone erosion, significantly reduced synovitis, and down-regulated the inflammatory cytokine expression. Most notably, the co-delivery strategy almost entirely restored the morphological features of the ankle joints of RA rats. The hepatic and renal function tests indicated good biological safety for DD NP HG in RA conditions. Taken together, these findings indicated that DD NP HG could achieve good anti-inflammatory activity and reverse cartilage disruption through a synergistic effect between two nanoparticulate forms of MTX and PEITC, which can effectively improve the drawbacks of their free forms.

A nanostructured dual-drug loaded smart hydrogel (DD NP HG) was successfully constructed for the intra-articular delivery of MTX and PEITC to the affected joints of RA.The fabrication of the nanoformulation of both MTX (MTX NP) and PEITC (PEITC NE) aided in mitigating the drawbacks and drug-related side effects of the free form of drugs.DD NP HG markedly suppressed joint inflammation and protect against bone destruction in arthritic rats.This combination approach of PEITC and MTX (DD NP HG) synergistically improved anti-arthritic activity and reduced the adverse side effects in vivo.

Bio-extract amalgamated sodium alginate-cellulose nanofibres based 3D-sponges with interpenetrating BioPU coating as potential wound care scaffolds.

In this work, sodium alginate (SA) based "all-natural" composite bio-sponges were designed for potential application as wound care scaffold. The composite bio-sponges were developed from the aqueous amalgamation of SA and cellulose nanofibres (CNFs) in bio-extracts like Rice water (Rw) and Giloy extract (Ge). These sponges were modified by employing a simple coating strategy using vegetable oil-based bio-polyurethane (BioPU) to tailor their physicochemical and biological properties so as to match the specific requirements of a wound care scaffold. Bio-sponges with shared interpenetrating polymeric network structures were attained at optimized BioPU coating formulation. The interpenetration of BioPU chains within the sponge construct resulted in the formation of numerous micro-networks in the interconnected microporous structure of sponges (porosity ≥75%). The coated sponge showed a superior mechanical strength (compressive strength ~3.8 MPa, compressive modulus ~35 MPa) with appreciable flexibility and recoverability under repeated compressive loading-unloading cycles. A tunable degradation behaviour was achieved by varying BioPU coating concentrations owing to the different degree of polymer chain entanglement within the sponge construct. The physical entanglement of BioPU chains with core structural components of sponge improved their structural stability by suppressing their full fragmentation in water-based medium without affecting its swelling behaviour (swelling ratio > 1000%). The coated sponge surface has provided a suitable moist-adherent physical environment to support the adhesion and growth of skin cells (HaCaT cells). The MTT (3-(4,5-dimethyl thiazolyl-2)-2,5-diphenyltetrazolium bromide) assay and hemolytic assay revealed the non-toxic and biocompatible nature of coated sponges in vitro. Moreover, no signs of skin erythema or edema were observed during in vivo dermal irritation and corrosion test performed on the skin of Sprague Dawley (SD) rats. Our initial observations revealed the credibility of these sponges as functional wound care scaffolds as well as its diverse potential as a suitable substrate for various tissue engineering applications.

Comparative evaluation of a herbal mouthwash (Freshol) with chlorhexidine on plaque accumulation, gingival inflammation, and salivary Streptococcus mutans growth.

INTRODUCTION: Plaque accumulation and oral microorganisms are the main predisposing factors to various orodental infections and targeting these, therefore, can prove to be an effective way of combating these diseases. Herbal extracts have been of particular interest these days owing to various side effects associated with conventional modes of treatment. AIMS AND OBJECTIVES: The present study was conducted to compare the efficacy of a commercially available homeopathic mouthwash with chlorhexidine on plaque status, gingival status, and salivary Streptococcus mutans count. MATERIALS AND METHODS: Total sample of 55 children, aged 8-14 years, were randomly divided into two groups. Group A (35) and Group B (20) were given 10 mL of test mouthwash "Freshol" and chlorhexidine respectively during phases 1 and 3 of the clinical trial which was of 10 days each. Phase 2 of 14 days in between was the washout period during which no mouthwash was given. RESULT: Freshol was found to be better than chlorhexidine in reducing the salivary mutans streptococci count and equieffective to chlorhexidine in altering plaque and gingival scores. CONCLUSION: Herbal alternatives can prove to be an effective and safe alternative to conventional modes of treatment.