Tandem Reactions of Electrophilic Indoles toward Indolizines and Their Subsequent Transformations through Pd(II)-Mediated C-H Functionalization to Access Polyring-Fused N-Heterocycles

A simple and efficient synthetic approach for generating a library of structurally novel indolizines has been developed via sequential 1,3-dipolar cycloaddition-ring opening processes. Using this methodology, a series of indolizines bearing different substituents were made in moderate to good yields. The presence of two functionalizable C-H bonds in these indolizine motifs makes them attractive for accessing fused indolizine scaffolds. In this line, we have introduced palladium-mediated site-selective C-H functionalizations, where the N-center and the two C-H centers of the indolizine moiety can be readily functionalized to generate fused N-heterocycles. Utilizing a Pd-mediated dual C-H activation of 5-benzoyl-substituted indolizine afforded 6H-indeno-indolizine, and a tetracene, viz., indolizino[2,1-b]indoles, was produced in the same substrate by the Pd-catalyzed selective C-H amination in the presence of oxygen.

Single Nucleotide Polymorphisms [SNPs] in the Shadows: Uncovering their Function in Non-Coding Region of Esophageal Cancer

Esophageal cancer is a complex disease influenced by genetic and environmental factors. Single nucleotide polymorphisms [SNPs] in non-coding regions of the genome have emerged as crucial contributors to esophageal cancer susceptibility. This review provides a comprehensive overview of the role of SNPs in non-coding regions and their association with esophageal cancer. The accumulation of SNPs in the genome has been implicated in esophageal cancer risk. Various studies have identified specific locations in the genome where SNPs are more likely to occur, suggesting a location-specific response. Chromatin conformational studies have shed light on the localization of SNPs and their impact on gene transcription, posttranscriptional modifications, gene expression regulation, and histone modification. Furthermore, miRNA-related SNPs have been found to play a significant role in esophageal squamous cell carcinoma [ESCC]. These SNPs can affect miRNA binding sites, thereby altering target gene regulation and contributing to ESCC development. Additionally, the risk of ESCC has been linked to base excision repair, suggesting that SNPs in this pathway may influence disease susceptibility. Somatic DNA segment alterations and modified expression quantitative trait loci [eQTL] have also been associated with ESCC. These alterations can lead to disrupted gene expression and cellular processes, ultimately contributing to cancer development and progression. Moreover, SNPs have been found to be associated with the long non-coding RNA HOTAIR, which plays a crucial role in ESCC pathogenesis. This review concludes with a discussion of the current and future perspectives in the field of SNPs in non-coding regions and their relevance to esophageal cancer. Understanding the functional implications of these SNPs may lead to the identification of novel therapeutic targets and the development of personalized approaches for esophageal cancer prevention and treatment.

Production and characterization of biosurfactant produced by a novel Pseudomonas sp. 2B

Biosurfactant-producing bacteria were isolated from terrestrial samples collected in areas contaminated with petroleum compounds. Isolates were screened for biosurfactant production using Cetyl Tri Ammonium Bromide (CTAB)-Methylene blue agar selection medium and the qualitative drop-collapse test. An efficient bacterial strain was selected based on rapid drop collapse activity and highest biosurfactant production. The biochemical characteristics and partial sequenced 16S rRNA gene of isolate, 2B, identified the bacterium as Pseudomonas sp. Five different low cost carbon substrates were evaluated for their effect on biosurfactant production. The maximum biosurfactant synthesis (4.97 g/L) occurred at 96 h when the cells were grown on modified PPGAS medium containing 1% (v/v) molasses at 30 °C and 150 rpm. The cell free broth containing the biosurfactant could reduce the surface tension to 30.14 mN/m. The surface active compound showed emulsifying activity against a variety of hydrocarbons and achieved a maximum emulsion index of 84% for sunflower oil. Compositional analysis of the biosurfactant reveals that the extracted biosurfactant was a glycolipid type, which was composed of high percentages of lipid (∼65%, w/w) and carbohydrate (∼32%, w/w). Fourier transform infrared (FT-IR) spectrum of extracted biosurfactant indicates the presence of carboxyl, hydroxyl and methoxyl functional groups. The mass spectra (MS) shows that dirhamnolipid (l-rhamnopyranosyl-l-rhamnopyranosyl-3-hydroxydecanoyl-3-hydroxydecanoate, Rha-Rha-C(10)-C(10)) was detected in abundance with the predominant congener monorhamnolipid (l-rhamnopyranosyl-β-hydroxydecanoyl-β-hydroxydecanoate, Rha-C(10)-C(10)). The crude oil recovery studies using the biosurfactant produced by Pseudomonas sp. 2B suggested its potential application in microbial enhanced oil recovery and bioremediation.

Association between protein bound sialic acid and high sensitivity C-reactive protein in prehypertension: a possible indication of underlying cardiovascular risk

The global burden posed by cardiovascular disease due to a rising incidence of known risk factors like essential hypertension underlines an urgent need to identify other potential risk factors like dyslipidemia, elevated levels of high-sensitivity CRP (hsCRP), Apo-B, and sialic acid in prehypertensive subjects. This study sought to examine the possible alteration in the levels of hsCRP, plasma protein bound sialic acid, and other lipid risk factors and the possible interactions among these parameters in prehypertensive subjects. Forty prehypertensive and 34 normotensive male subjects were enrolled in the study. Lipid profile, hsCRP, Apo-B, sialic acid, and lipid risk ratios were estimated in both the groups. There was no significant difference between fasting glucose and BMI in either group. The levels of total cholesterol, triglycerides, direct LDL-cholesterol, non-HDL cholesterol, and Apo-B were significantly increased in prehypertensive subjects compared with controls. The risk ratios calculated as direct LDL-cholesterol/Apo-B, total cholesterol/HDL-cholesterol, non-HDL-cholesterol/HDL-cholesterol were significantly elevated in prehypertensive subjects. There was also a significant increase in hsCRP and protein bound sialic acid in prehypertensive subjects in comparison with normotensive subjects. Correlation analysis revealed a significant association between the protein bound sialic acid with hsCRP, LDL cholesterol, and LDL-C/Apo-B. The findings of the present study suggest that in prehypertension, there is an association between protein bound sialic acid and hsCRP that reflects the clustering of cardiovascular risk factors in these subjects.