Anticancer, antimicrobial, antioxidant, and catalytic activities of green-synthesized silver and gold nanoparticles using Bauhinia purpurea leaf extract.

The synthesis of metal nanoparticles by green methods attained enormous attention in recent years due to its easiness, non-toxicity, and eco-friendly nature. In the present study, noble metal nanoparticles such as silver and gold were prepared using an aqueous leaf extract of a medicinal plant, Bauhinia purpurea. The leaf extract performed as both reducing and stabilizing agents for the development of nanoparticles. The formations of silver and gold nanoparticles were confirmed by observing the surface plasmon resonance peaks at 430 nm and 560 nm, respectively, in UV-Vis absorption spectrum. Various properties of nanoparticles were demonstrated using the characterization techniques such as FTIR, XRD, TEM, and EDX. The synthesized silver and gold nanoparticles had a momentous anticancer effect against lung carcinoma cell line A549 in a dose-dependent manner with IC50 values of 27.97 µg/mL and 36.39 µg/mL, respectively. The antimicrobial studies of synthesized nanoparticles were carried out by agar well diffusion method against six microbial strains. Silver and gold nanoparticles were also showed high antioxidant potentials with IC50 values of 42.37 µg/mL and 27.21 µg/mL, respectively; it was measured using DPPH assay. Additionally, the nanoparticles were observed to be good catalysts for the reduction of organic dyes.

Eco-friendly synthesis of silver and gold nanoparticles with enhanced antimicrobial, antioxidant, and catalytic activities.

The present work is emphasised on the bio-fabrication of silver and gold nanoparticles in a single step by a microwave-assisted method using the leaf extract of Synedrella nodiflora as both reducing and stabilising agent. The synthesised nanoparticles are highly stable and show surface plasmon resonance peak at 413 and 535 nm, respectively, for silver and gold nanoparticles in UV-Vis spectrum. The functional group responsible for the reduction of metal ions were obtained from Fourier transform infrared spectroscopy. The crystalline nature of nanoparticles with face-centred cubic geometry was confirmed by the X-ray diffraction and selected area electron diffraction patterns. The morphology and sizes of the silver and gold nanoparticles were obtained from transmission electron microscopy images. The nanoparticles exhibit effective antimicrobial activities against various pathogenic strains. These antimicrobial properties were analysed by employing agar well diffusion method. The nanoparticles show significant antioxidant properties, and it was determined using 2, 2-diphenyl-1-picrylhydrazyl assay. The nanoparticles also show potent catalytic activity in the degradation of anthropogenic pollutant dyes Congo red and eosin Y by excess NaBH4. Thus, the current study demonstrates the potential use of S. nodiflora as a reducing and stabilising agent for the synthesis of silver and gold nanoparticles and their relevance in the field of biomedicine and catalysis.

Indigofera tinctoria leaf extract mediated green synthesis of silver and gold nanoparticles and assessment of their anticancer, antimicrobial, antioxidant and catalytic properties.

This study reports the synthesis of noble metal nanoparticles, namely silver and gold from their respective salt by leaf extract of a medicinal plant Indigofera tinctoria. This leaf extract plays a dual role as stabilizing and reducing agent for the formation of nanoparticles. The synthesized silver and gold nanoparticles were characterized by UV-vis. spectroscopy, FTIR spectroscopy, XRD, TEM, EDX and AFM analysis. All these techniques confirm the formation of crystalline nanoparticles. The cytotoxic effect of I. tinctoria leaf extract and the nanoparticles were studied on lung cancer cell line A549. It was shown that the cell viability decreases with increasing concentration and nanoparticles has more toxic effect on cancer cell than the pure leaf extract. IC50 value of I. tinctoria leaf extract, AuNP and AgNP respectively, are 71.92 ± 0.76 µg/ml, 59.33 ± 0.57 µg/ml and 56.62 ± 0.86 µg/ml. Antimicrobial activities were tested against both bacterial and fungal strains by agar well diffusion method. The synthesized nanoparticles show high antimicrobial activities towards all tested microbial strains with varying degree. The antioxidant activities of synthesized nanoparticles were analysed by using DPPH method and found that nanoparticles show higher antioxidant activities than the leaf extract. Outstanding catalytic activities of nanoparticles were demonstrated by employing the reduction reactions of o/p-niroanilines by NaBH4.

Microwave assisted green synthesis of silver nanoparticles using leaf extract of elephantopus scaber and its environmental and biological applications.

The fabrication of spherical silver nanoparticles using the phytoreducing agent Elephantopus scaber is reported here. Irradiation of the reaction mixture under a domestic microwave oven enabled the formation of stable silver nanoparticles and was confirmed by UV-vis spectral portrait. Chemical components inherent in the aqueous leaf extract which reduces the monovalent silver were identified by FT-IR spectroscopy. The crystal structure of the synthesized nanoparticles was established as face centred cube by the powder XRD analysis. The TEM images suggest an average particle size of 37.86 nm to the silver nanoparticles. The prepared silver nanocatalysts can successfully reduce various organic nitro compounds, namely, 4-nitrophenol, 2-nitroaniline and 4-nitroaniline. The environmental pollution caused by dyes like eosin Y is effectively wiped off within a short span of time using the prepared nanocatalysts. The free radical quenching efficacy of the plant extract and the silver nanoparticles were checked by employing DPPH assay bestowing ascorbic acid reference. The potential of the nanoparticles as antimicrobials against six human disease causing pathogens were tested through the well diffusion pathway. The newly developed silver nanoparticles produced IC50 value 15.68 ± 0.15 µg/mL on human skin carcinoma cells, A375 and 65.49 ± 0.40 µg/mL on fibroblast cells, L929 when the cytotoxicity is studied employing MTT assay. Elephantopus scaber showed IC50 value 50.55 ± 0.17 µg/mL against A375 cells.

Green synthesis and characterization of gold and silver nanoparticles using Mussaenda glabrata leaf extract and their environmental applications to dye degradation.

Plant-derived nanomaterials opened a green approach in solving the current environment issues. Present study focused on rapid microwave-assisted synthesis and applications of gold and silver nanoparticles mediated by aqueous leaf extract of Mussaenda glabrata. The synthesized nanoparticles were characterized by UV-vis, FT-IR, powder XRD, energy-dispersive X-ray spectroscopy (EDX), transmission electron (TEM), and atomic force microscopic techniques (AFM). FCC crystal structure of both nanoparticles was confirmed by peaks corresponding to (111), (200), (220), and (311) planes in XRD spectra and bright circular spots in SAED pattern. IC50 values shown by gold and silver nanoparticles (44.1 ± 0.82 and 57.92 ± 1.33 µg/mL) reflected their high free radical scavenging potential. The synthesized gold and silver nanoparticles revealed their potency to inhibit pathogenic microorganisms Bacillus pumilus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Aspergillus niger, and Penicillium chrysogenum. Anthropogenic pollutants rhodamine B and methyl orange were effectively degraded from aquatic environment and waste water sewages of dye industries using the prepared nanocatalysts. The catalytic capacities of the synthesized nanoparticles were also exploited in the reduction of 4-nitrophenol. Graphical abstract.

Carbimazole-induced agranulocytosis.

UNLABELLED: A 47 year old lady with hyperthyroidism for past 1½ years was initially on Carbimazole 20 mg orally then changed to 30 mg (during Hysterectomy) but was taking 10 mg for last 1 year. She had intermittent fever with severe B/L bifrontal headache since 3 weeks. Routine investigations showed anaemia, neutropenia, leucopenia and CRP elevation. Peripheral smear showed normocytic normochromic anaemia with Rouleaux formation, leucopenia with 2% atypical cells and mild thrombocytosis. Widal test, RA factor (Rheumatoid factor) test, Ig M (Immunoglobulin M) dengue, Ig M Lepto, TORCH infections (Toxoplasmosis, Other (Syphilis, varicella-zoster, parvovirus B19), Cytomegalovirus and Herpes infections), ANA (Antinuclear antibody) screen cANCA (Cytoplasmic antineutrophil cytoplasmic antibodies) and pANCA (Perinuclear Anti-Neutrophil Cytoplasmic Antibodies) tests were negative. Bone marrow aspiration showed normo to hypercellular marrow with 15% atypical cells and plasma cells. Multiple myeloma workup was done. Carbimazole was withheld. CONCLUSION: Drug induced agranulocytosis occurs with in 1-2 months of taking the antithyroid medication but onset delayed by 1½ year. De-challenge resulted normalization of blood parameters.

Microwave assisted facile green synthesis of silver and gold nanocatalysts using the leaf extract of Aerva lanata.

Herein, we report a simple microwave assisted method for the green synthesis of silver and gold nanoparticles by the reduction of aqueous metal salt solutions using leaf extract of the medicinal plant Aerva lanata. UV-vis., FTIR, XRD, and HR-TEM studies were conducted to assure the formation of nanoparticles. XRD studies clearly confirmed the crystalline nature of the synthesized nanoparticles. From the HR-TEM images, the silver nanoparticles (AgNPs) were found to be more or less spherical and gold nanoparticles (AuNPs) were observed to be of different morphology with an average diameter of 18.62nm for silver and 17.97nm for gold nanoparticles. In order to evaluate the effect of microwave heating upon rate of formation, the synthesis was also conducted under ambient condition without the assistance of microwave radiation and the former method was found to be much faster than the later. The synthesized nanoparticles were used as nanocatalysts in the reduction of 4-nitrophenol to 4-aminophenol by NaBH4.

A review of newer treatment approaches for type-2 diabetes: Focusing safety and efficacy of incretin based therapy.

Diabetes resulting from both genetic and lifestyle factors causes high insulin deficiency or its resistance. As hyperglycemia and decreased insulin secretion and/or its sensitivity appear to be the primary defects associated with diabetes, available treatments focus on reducing those defects. A novel approach of treatment is to target the incretin mimetic hormones, which are secreted by intestinal cells in response to food intake, provoking glucose-dependent insulin secretion from the pancreas. Efficacy and safety studies of dipetidyl peptidase inhibitors (DPP-IV), sitagliptin, vildagliptin and linagliptin provide similar improvements in HbA1c levels when compared with metformin, sulfonylureas or glitazones without contributing to weight gain and hypoglycemia. Caution is required when choosing the gliptin in people with renal or hepatic impairment and with a risk of pancreatitis. The glucagon like peptide (GLP-1) analogues Exenatide and Liraglutide also have positive impact on glycemic control especially when used as a combination therapy. Another upcoming approach is using sodium-glucose co transporter two inhibitors in kidney, by exploring pathophysiology of renal glucose re absorption in the proximal tubule.

Migraine management: How do the adult and paediatric migraines differ?

Migraine is one of the common causes of severe and recurring headache. It may be difficult to manage in primary care settings, where it is under diagnosed and medically treated. Migraine can occur in children as well as in adults and it is three times more common in women than in men. Migraine in children is different from adults in various ways. Migraine management depends on the various factors like duration and severity of pain, associated symptoms, degree of disability, and initial response to treatment. The therapy of children and adolescents with migraines includes treatment modalities for acute attacks, prophylactic medications when the attacks are frequent, and biobehavioural modes of treatment to aid long-term management of the disorder. The long lasting outcome of childhood headaches and progression into adult headaches remains largely unknown. However, it has been suggested that adult migraine may represent a progressive disorder. In children, the progressive nature is uncertain and further investigations into longitudinal outcome and phenotypic changes in childhood headaches have yet to be recognized. Even though paediatric and adult migraines seem to be slightly different from one another, but not enough to categorize either as sole.