Unpacking Phthalates from Obscurity in the Environment.

Phthalates (PAEs) are a group of synthetic esters of phthalic acid compounds mostly used as plasticizers in plastic materials but are widely applied in most industries and products. As plasticizers in plastic materials, they are not chemically bound to the polymeric matrix and easily leach out. Logically, PAEs should be prevalent in the environment, but their prevalence, transport, fate, and effects have been largely unknown until recently. This has been attributed, inter alia, to a lack of standardized analytical procedures for identifying them in complex matrices. Nevertheless, current advancements in analytical techniques facilitate the understanding of PAEs in the environment. It is now known that they can potentially impact ecological and human health adversely, leading to their categorization as endocrine-disrupting chemicals, carcinogenic, and liver- and kidney-failure-causing agents, which has landed them among contaminants of emerging concern (CECs). Thus, this review article reports and discusses the developments and advancements in PAEs' standard analytical methods, facilitating their emergence from obscurity. It further explores the opportunities, challenges, and limits of their advancements.

Adsorption of doxorubicin on citrate-capped gold nanoparticles: insights into engineering potent chemotherapeutic delivery systems.

Gold nanomaterials have received great interest for their use in cancer theranostic applications over the past two decades. Many gold nanoparticle-based drug delivery system designs rely on adsorbed ligands such as DNA or cleavable linkers to load therapeutic cargo. The heightened research interest was recently demonstrated in the simple design of nanoparticle-drug conjugates wherein drug molecules are directly adsorbed onto the as-synthesized nanoparticle surface. The potent chemotherapeutic, doxorubicin often serves as a model drug for gold nanoparticle-based delivery platforms; however, the specific interaction facilitating adsorption in this system remains understudied. Here, for the first time, we propose empirical and theoretical evidence suggestive of the main adsorption process where (1) hydrophobic forces drive doxorubicin towards the gold nanoparticle surface before (2) cation-π interactions and gold-carbonyl coordination between the drug molecule and the cations on AuNP surface facilitate DOX adsorption. In addition, biologically relevant compounds, such as serum albumin and glutathione, were shown to enhance desorption of loaded drug molecules from AuNP at physiologically relevant concentrations, providing insight into the drug release and in vivo stability of such drug conjugates.

Efficacy of natural diosgenin on cardiovascular risk, insulin secretion, and beta cells in streptozotocin (STZ)-induced diabetic rats.

Costus igneus, has been prescribed for the treatment of diabetic mellitus in India for several years. The aim of this study is to investigate the effects of plant derived diosgenin on cardiovascular risk, insulin secretion, and pancreatic composition through electron microscopical studies of normal and diabetic rats. Diosgenin at a dose of 5 or 10mg/kg per body weight (bw) was orally administered as a single dose per day to diabetic induced rats for a period of 30 days. The effect of diosgenin on blood glucose, HbA1c, PT, APTT, Oxy-LDL, serum lipid profile, electron microscopical studies of pancreas, antioxidant enzymes (in liver, kidney, pancreas) and hepatoprotective enzymes in plasma and liver were measured in normal and diabetic rats. The results showed that fasting blood glucose, PT, APTT, Oxy-LDL, TC, TG, LDL, ALT, AST, ALP, glucose-6-phosphatase, fructose-1,6-bisphosphatase and LPO levels were significantly (p<0.05) increased, whereas HDL, SOD, CAT, GSH and the glycolytic enzyme glucokinase levels were significantly (p<0.05) decreased in the diabetes induced rats and these levels were significantly (p<0.05) reversed back to normal in diabetes induced rats after 30 days of treatment with diosgenin. Electron microscopical studies of the pancreas revealed that the number of beta cells and insulin granules were increased in streptozotocin (STZ) induced diabetic rats after 30 days of treatment with diosgenin. In conclusion, the data obtained from the present study strongly indicate that diosgenin has potential effects on cardiovascular risk, insulin secretion and beta cell regeneration in STZ induced diabetic rats, these results could be useful for new drug development to fight diabetes and its related cardiovascular diseases.

Conventional and nanotechniques for DNA methylation profiling.

DNA methylation is critical for gene silencing and is associated with the incidence of many diseases, including cancer. Underlying molecular mechanisms of human diseases and tissue-specific gene expression have been elucidated based on DNA methylation studies. This review highlights the advantages and drawbacks of various methylation screening techniques: blotting, genomic sequencing, bisulfite sequencing, methylation-specific PCR, methylated DNA immunoprecipitation, microarray analysis, matrix-assisted laser desorption ionization time-of-flight mass spectroscopy, nanowire transistor detection procedure, quantum dot-based nanoassay, single-molecule real-time detection, fluorimetric assay, electrochemical detection, and atomic force spectroscopy. The review provides insight for selecting a method or a combination of methods for DNA methylation analysis. Convergence of conventional and contemporary nanotechniques to enumerate methylation at specific CpG sites of oncogene would fill the gap in diagnosis of cancer.

Carbon distribution to toxic effect in toxin proteins.

The role of hydrophobic force in biological function through the formation of several local macro-molecular structures is evident. Carbon is the element that contributes to biological function in living systems. We show that carbon distribution is related to protein activity using an example. The carbon distribution profile is foreseen to help undestand unfolded and misfolded regions of protein structures. The carbon distribution profile in a toxin protein that is found associated with the toxic shock syndrome is described in this study. The carbon profile provides insight to the association of specific residues responsible for toxicity.

In vitro evaluation of calcium oxalate monohydrate crystals influenced by Costus igneus aqueous extract.

OBJECTIVE: Calcium oxalate monohydrate (COM) crystals are frequently found in urinary calculi (stones). MATERIAL AND METHODS: COM crystals were grown by the single diffusion gel growth technique and the inhibitory effects of aqueous extracts of leaves, stems and rhizome of Costus igneus on the growth of COM crystals were studied. RESULTS: With an increase in the concentration of aqueous extract of C. igneus, the weight of the formed crystals was gradually reduced from 2.15 to 0.07 g(leaves), 0.06 g (rhizome) and 0.03 g (stem). The crystals harvested from the COM were characterized by Fourier transform infrared spectroscopy to confirm the functional groups and powder X-ray diffraction analyses to confirm the crystalline phases of COM crystals. A scanning electron microscopy study confirmed that the morphology of the crystals changed from hexagonal (COM) to bipyramids of calcium oxalate dihydrate (COD). CONCLUSIONS: This study confirms that using aqueous extracts of stem and rhizome of C. igneus can promote the formation of COD crystals and reduce the nucleation rate of COM crystals, a major component of calcium urinary stones.