Biotechnological Approaches for Production of Artemisinin,an Anti-Malarial Drug from Artemisia annua L.

Artemisinin is an anti-malarial sesquiterpene lactone derived from Artemisia annua L. (Asteraceae family). One of the most widely used modes of treatment for malaria is an artemisinin-based combination therapy. Artemisinin and its associated compounds have a variety of pharmacological qualities that have helped achieve economic prominence in recent years. So far, research on the biosynthesis of this bioactive metabolite has revealed that it is produced in glandular trichomes and that the genes responsible for its production must be overexpressed in order to meet demand. Using biotechnological applications such as tissue culture, genetic engineering, and bioreactor-based approaches would aid in the upregulation of artemisinin yield, which is needed for the future. The current review focuses on the tissue culture aspects of propagation of A. annua and production of artemisinin from A. annua L. cell and organ cultures. The review also focuses on elicitation strategies in cell and organ cultures, as well as artemisinin biosynthesis and metabolic engineering of biosynthetic genes in Artemisia and plant model systems.     

Usage of Platinum Nanoparticles for Anticancer Therapy over Last Decade: A Review

The quest for new functional nanomaterials is one of the defining purposes of nanoscience and nanotechnology. A large number of metal nanoparticles (NPs) are extensively exploited for biomedical applications. Metal NPs, in particular platinum NPs (PtNPs), possess remarkable properties that make them a potential candidate as a diagnostic or therapeutic agent. Due to potential technological interest over the last decade, PtNPs have attracted much attention in the field of anticancer research. PtNPs, when conjugated with many functionalizing agents such as polymers, ligands, drugs, peptides, and surfactants, exhibit improved targeting and reduced cytotoxic effects in various cancers. The PtNPs conjugated with folic acid, graphene oxide, and iron NPs are gained more attention due to their stability, large surface area, and reduced toxicity. To achieve this goal, PtNPs are co-loaded with drugs or other modalities that offer an opportunity for multimodal activity in the frame of treating cancer types focusing on breast, blood, lung, ovarian, skin, liver, etc. However, a review of PtNPs’ function in diagnosis and treatment is still lacking. In this review, the effectiveness of PtNPs toward inducing and elevating death of the cancerous cells proving its delivery approaches and antitumor nature, concluding with future perspectives, are summarized.     

Nanostructured ZnO and ZnO: Pd with MXene overlayer SPR biosensors

Optical and Quantum Electronics - In this article, Bernoulli $$(G'/G)$$ -expansion method, which is proposed in this research work, and $$(G'/G)$$ -expansion method are applied to find...     

Graph triangulations and the compatibility of unrooted phylogenetic trees

We characterize the compatibility of a collection of unrooted phylogenetic trees as a question of determining whether a graph derived from these trees — the display graph — has a specific kind of triangulation, which we call legal. Our result is a counterpart to the well-known triangulation-based characterization of the compatibility of undirected multi-state characters.     

Molecular Encapsulation of Fluorescent Dyes Affords Efficient Narrow‐band Dye Laser Operation in Water

A water‐based narrow‐band high‐efficiency dye laser was designed by means of a supramolecular host–guest chemical approach. The lasing characteristics of rhodamine B and sulforhodamine B (Kiton Red S) dyes in aqueous solution with the macrocyclic host cucurbit[7]uril (CB7) as additive were investigated in a narrow‐band dye laser setup. Significant improvements in both photostability and thermo‐optical properties of the aqueous CB7‐complexed dye systems were observed as compared to the uncomplexed dyes in ethanol solution. The tuning curves for the new dye–CB7–water systems were constructed by measuring the laser output at different wavelengths, which showed similar peak efficiencies and red‐shifted gains compared to the ethanolic solutions of the dyes, while dye laser operation revealed comparable pump threshold energies and slope efficiencies. The combined results render the dye–CB7–water system an attractive active medium for high‐repetition rate dye laser operation.     

Dissolvable membranes as sensing elements for microfluidics based biological/chemical sensors

We demonstrate a chemical and biological sensing mechanism in microfluidics that transduces chemical and biological signals to electrical signals with large intrinsic amplification without need for complex electronics. The sensing mechanism involves a dissolvable membrane separating a liquid sample chamber from an interdigitated electrode. Dissolution of the membrane (here, a disulfide cross-linked poly(acrylamide) hydrogel) in the presence of a specific target (here, a reducing agent-dithiothreitol) allows the target solution to flow into contact with the electrode. The liquid movement displaces the air dielectric with a liquid, leading to a change (open circuit to approximately 1 kOmega) in the resistance between the electrodes. Thus, a biochemical event is transduced into an electrical signal via fluid movement. The concentration of the target is estimated by monitoring the difference in dissolution times of two juxtaposed sensing membranes having different dissolution characteristics. No dc power is consumed by the sensor until detection of the target. A range of targets could be sensed by defining membranes specific to the target. This sensing mechanism might find applications in sensing targets such as toxins, which exhibit enzymatic activity.     

An asymptotic approximation for TCP CUBIC

Queueing Systems - In this paper, we derive an expression for computing the average window size of a single TCP CUBIC connection under random losses. For this we consider a throughput expression...     

Iron catalyzed highly regioselective dimerization of terminal aryl alkynes

Iron can catalyze head-to-head dimerization of terminal aryl alkynes to give the corresponding (E) selective conjugated enynes in high yields. A variety of substituted aryl acetylenes underwent smooth dimerization using catalytic FeCl(3) and DMEDA in the presence of KO(t)Bu.     

Scope of a novel three-component synthesis of highly functionalized pyridines(dagger)

A mechanistically unique three-component synthesis provides a variety of functionalized pyridine derivatives in fair to excellent yields. The scope of this reaction was studied with respect to the alkoxyallene, the nitrile, and the carboxylic acid. Due to the 4-hydroxy group, these pyridine derivatives are suitable precursors for subsequent palladium-catalyzed reactions. Suzuki couplings of the corresponding pyridyl nonaflates lead to a variety of pyridine and bipyridine derivatives.     

Lead(IV) acetate: intriguing reactivity profile

LTA reaction of homoallyl alcohols derived from norbornyl alpha-diketones exclusively furnished the corresponding alpha-diketones via beta-fragmentation of the allyl group in refluxing benzene while changing the solvent to MeOH resulted in the formation of novel methoxy substituted spirocyclic tetrahydrofuran products.