Elucidating the Mechanism of Copper-Induced Photoluminescence Quenching in 2-Phenylbenzimidazole-5-Sulfonic Acid.

To explore the possible impact of 2-Phenylbenzimidazole-5-sulfonic acid (PBSA) on the function of a sunscreen, in this work we investigate the binding of copper metal ions (Cu2+) to PBSA. Due to the existence of an intrinsic interaction phenomenon between Cu2+ ions and PBSA molecules, the photoluminescence (PL) quenching arises owing to the charge transfer from PBSA to Cu2+ ions. The mechanism of fluorescence quenching is probed experimentally following excitation at 306 nm by evaluating various quenching parameters with the help of the Stern-Volmer plot. Through the assessment of the values of the Stern-Volmer constant ( K SV = 45.2 M - 1 ) and bimolecular quenching rate constant ( k q = 0.77 × 10 10 M - 1 . s - 1 ), it is deduced that the dynamic mode of PL quenching is operative between PBSA and Cu2+ ions. We evaluate the number of binding sites (n = 1) that advocate the presence of a single binding site in PBSA for Cu2+ ions. The numerical value of standard Gibbs free energy change, Δ G o ~ -27.485 kJ.mol-1 implies the spontaneous binding between Cu2+ ions and PBSA molecules. The results obtained give an insight into the mechanism of metal-induced PL quenching of water soluble PBSA sunscreen.

A preparation of bacterial outer membrane with osmium tetroxide and uranyl acetate co-stain enables improved structural determination by transmission electron microscopy.

Biological nanoparticles, such as bacterial outer membrane vesicles (OMVs), are routinely characterized through transmission electron microscopy (TEM). In this study, we report a novel method to prepare OMVs for TEM imaging. To preserve vesicular shape and structure, we developed a dual fixation protocol involving osmium tetroxide incubation prior to negative staining with uranyl acetate. Combining osmium tetroxide with uranyl acetate resulted in preservation of sub-50 nm vesicles and improved morphological stability, enhancing characterization of lipid-based nanoparticles by TEM.

Exosomes, microvesicles, and other extracellular vesicles-a Keystone Symposia report.

Extracellular vesicles (EVs) are small, lipid-bilayer-bound particles released by cells that can contain important bioactive molecules, including lipids, RNAs, and proteins. Once released in the extracellular environment, EVs can act as messengers locally as well as to distant tissues to coordinate tissue homeostasis and systemic responses. There is a growing interest in not only understanding the physiology of EVs as signaling particles but also leveraging them as minimally invasive diagnostic and prognostic biomarkers (e.g., they can be found in biofluids) and drug-delivery vehicles. On October 30-November 2, 2022, researchers in the EV field convened for the Keystone symposium "Exosomes, Microvesicles, and Other Extracellular Vesicles" to discuss developing standardized language and methodology, new data on the basic biology of EVs and potential clinical utility, as well as novel technologies to isolate and characterize EVs.

An Updated and Focused Review on Heterocyclic Inhibitors for SARSCoV and SARS-CoV-2 3CLpro.

BACKGROUND: SARS-CoV and SARS-CoV-2 are exceedingly contagious and typically result in major respiratory illnesses (acute respiratory syndrome). The public health is facing enormous challenges across all the nations due to these newly emerging pathogens. Reliable and systematic examination of SARS-CoV and COVID-19 will assist in identifying infectious persons accurately. Based on the biological, chemical, and genetic link of SARS CoV-2 towards SARS-CoV, the recurrence of different anti-SARS-CoV natural drug molecules may be beneficial in the advancement of anti-COVID-19 herbal drug molecules. Here in this review, we evaluated SAR research that has recently been published as well as molecular docking analysis of previously synthesised compounds that have been targeted against SARS-CoV and SARS-CoV-2, respectively. This investigation might assist scientists in creating novel and revolutionary molecules that could target SAR-CoV-2. OBJECTIVES: The review highlights the heterocyclic inhibitors' ability to successfully inhibit SARSCoV and SARS-CoV-2. The meticulously described structure-activity relationship of potential SARS-CoV and SARS-CoV-2 inhibiting compounds has been addressed in this review. EVIDENCE ACQUISITION: We conducted a thorough literature assessment employing electronic databases for scientific articles highlighting potential heterocyclic inhibitors for SARS-CoVand SARSCoV- 2, published from 2010 to 2021. We recovered 415 articles, but only 220 were involved and conversed in this manuscript. The article apprehended appropriate research considering three areas: 1) SAR activity, 2) Molecular docking, and 3) Biological activity and future prospects on SARS-CoV-2. METHODS: The potential compounds with decent inhibitory activity have been discussed and reviewed along with their inhibition potential, expressed in terms of IC50 value. RESULTS: Heterocyclic scaffolds reflect an extensive spectrum of therapeutic activity and might function as an initiating concept for the designing and discovery of potential inhibitors for SARS-CoV and SARS-CoV-2 treatment. CONCLUSION: The points highlighted here may prove to be a vital tool for medicinal chemists working/ investigating more potent and efficacious scaffolds in treating SARS-CoV and SARS-CoV-2.

Withdrawn: Biomarkers in Disease Diagnosis and the Role of LC-MS and NMR: A Review

The article has been withdrawn at the request of the editor of the journal Current Pharmaceutical Design.Bentham Science apologizes to the readers of the journal for any inconvenience this may have caused.The Bentham Editorial Policy on Article Withdrawal can be found at https://benthamscience.com/editorial-policies-main.php. Bentham Science Disclaimer: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript, the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication. ©

The Utility of Smartphone-Based Artificial Intelligence Approaches for Diabetic Retinopathy: A Literature Review and Meta-Analysis.

PURPOSE: To assess the diagnostic accuracy measures such as sensitivity and specificity of smartphone-based artificial intelligence (AI) approaches in the detection of diabetic retinopathy (DR). METHODS: A literature search of the EMBASE and MEDLINE databases (up to March 2020) was conducted. Only studies using both smartphone-based cameras and AI software for image analysis were included. The main outcome measures were pooled sensitivity and specificity, diagnostic odds ratios and relative risk of smartphone-based AI approaches in detecting DR (of all types), and referable DR (RDR) (moderate nonproliferative retinopathy or worse and/or the presence of diabetic macular edema). RESULTS: Smartphone-based AI has a pooled sensitivity of 89.5% (95% confidence interval [CI]: 82.3%-94.0%) and pooled specificity of 92.4% (95% CI: 86.4%-95.9%) in detecting DR. For referable disease, sensitivity is 97.9% (95% CI: 92.6%-99.4%), and the pooled specificity is 85.9% (95% CI: 76.5%-91.9%). The technology is better at correctly identifying referable retinopathy. CONCLUSIONS: The smartphone-based AI programs demonstrate high diagnostic accuracy for the detection of DR and RDR and are potentially viable substitutes for conventional diabetic screening approaches. Further, high-quality randomized controlled trials are required to establish the effectiveness of this approach in different populations.

Current Status of Novel Pyridine Fused Derivatives as Anticancer Agents: An Insight into Future Perspectives and Structure Activity Relationship (SAR).

Cancer is a heterogeneous disease characterized by an abnormal and uncontrolled division of the cells leading to tumors that invade the adjacent normal tissues. After cardiovascular diseases, it is the second most prevalent disease accounting for one in every six deaths worldwide. This alarming rate thus, demands an urgent need to investigate more effective drugs to combat the said disease. Oxygen and nitrogen-based heterocyclic compounds have shown remarkable therapeutic activity towards several diseases, including cancer. In this review, we have attempted to summarize the work done in the last decade (2009-2019), highlighting the anticancer activity of pyrido fused fivemembered heterocyclic ring derivatives. Additionally, we have focused on seven heterocyclic pyridine fused rings: Imidazopyridine, Triazolopyridine, Pyrrolopyridine, Pyrazolopyridines, Thienopyridine, and Isoxazolopyridine. A total of forty-nine compounds have been studied based on their invitro cytotoxic activity and their structure-activity relationship, underlining the anticancer activity of their various pharmacophores and substituents. This review, therefore, aims to draw the attention of the researchers worldwide towards the enormous scope of development of heterocyclic drug compounds, focussing mainly on pyrido fused five-membered heterocyclic rings as anticancer drugs.

Contribution of the microbiota and their secretory products to inflammation and colorectal cancer pathogenesis: the role of toll-like receptors.

Alterations in diversity and function of the gut microbiome are associated with concomitant changes in immune response, including chronic inflammation. Chronic inflammation is a major risk factor for colorectal cancer (CRC). An important component of the inflammatory response system are the toll-like receptors (TLRs). TLRs are capable of sensing microbial components, including nucleic acids, lipopolysaccharides and peptidoglycans, as well as bacterial outer membrane vesicles (OMV). OMVs can be decorated with or carry as cargo these TLR activating factors. These microbial factors can either promote tolerance or activate signaling pathways leading to chronic inflammation. Herein we discuss the role of the microbiome and the OMVs that originate from intestinal bacteria in promoting chronic inflammation and the development of colitis-associated CRC. We also discuss the contribution of TLRs in mediating the microbiome-inflammation axis and subsequent cancer development. Understanding the role of the microbiome and its secretory factors in TLR response may lead to the development of better cancer therapeutics.

Design, Synthesis, Molecular Docking, and Anticancer Evaluation of Pyrazole Linked Pyrazoline Derivatives with Carbothioamide Tail as EGFR Kinase Inhibitors.

BACKGROUND: The Epidermal Growth Factor Receptor (known as EGFR) induces cell differentiation and proliferation upon activation through the binding of its ligands. Since EGFR is thought to be involved in the development of cancer, the identification of new target inhibitors is the most viable approach, which recently gained momentum as a potential anticancer therapy. OBJECTIVE: To assess various pyrazole linked pyrazoline derivatives with carbothioamide for EGFR kinase inhibitory as well as anti-proliferative activity against human cancer cell lines viz. A549 (non-small cell lung tumor), MCF-7 (breast cancer cell line), SiHa (cancerous tissues of the cervix uteri), and HCT-116 (colon cancer cell line). METHODS: In vitro EGFR kinase assay, in vitro MTT assay, Lactate dehydrogenase release, nuclear staining (DAPI), and flow cytometry cell analysis. RESULTS: Compounds 6h and 6j inhibited EGFR kinase at concentrations of 1.66µM and 1.9µM, respectively. Furthermore, compounds 6h and 6j showed the most potent anti-proliferative results against the A549 KRAS mutation cell line (IC50 = 9.3 & 10.2µM). Through DAPI staining and phase contrast microscopy, it was established that compounds 6h and 6j also induced apoptotic activity in A549 cells. This activity was further confirmed by FACS using Annexin-V-FITC and Propidium Iodide (PI) labeling. Molecular docking studies performed on 6h and 6j suggested that the compounds can bind to the hinge region of ATP binding site of EGFR tyrosine kinase in a similar pose as that of the standard drug gefitinib. CONCLUSION: The potential anticancer activity of compounds 6h and 6j was confirmed and need further exploration in cancer cell lines of different tissue origin and signaling pathways, as well as in animal models of cancer development.

Recent advancement in the discovery and development of anti-epileptic biomolecules: An insight into structure activity relationship and Docking.

Although there have been many advancements in scientific research and development, the cause of epilepsy still remains an open challenge. In spite of high throughput research in the field of anti-epileptic drugs, efficacy void is still prevalent before the researchers. Researchers have persistently been exploring all the possibilities to curb undesirable side effects of the anti-epileptic drugs or looking for a more substantial approach to diminish or cure epilepsy. The drug development has shown a hope to medicinal chemists and researchers to carry further research by going through a substantial literature survey. This review article attempts to describe the recent developments in the anti-epileptic agents, pertaining to different molecular scaffolds considering their structure-activity relationship, docking studies and their mechanism of actions.

Exploration of the Vaginal and Gut Microbiome in African American Women by Body Mass Index, Class of Obesity, and Gestational Weight Gain: A Pilot Study.

OBJECTIVE: This study determines the differences in the distal gut and vaginal microbiome in African American (AA) women by prepregnancy body mass index and gestational weight gain (GWG) comparing women with and without obesity and by obesity class. STUDY DESIGN: We prospectively sampled the vaginal and distal gut microbiome in pregnant AA women at two time points during pregnancy. Samples were analyzed using high-throughput sequencing of the V4 region of the 16S ribosomal ribonucleic acid gene. RESULTS: Distinct differences in vaginal and distal gut α-diversity were observed at time point 1 between women with and without obesity by total GWG. Significant differences in distal gut ß-diversity were also found at time point 1 in obese women by GWG. Within the Bacteroides genus, a significant association was observed by total GWG among obese women which was absent in nonobese women. Women with class III obesity who experienced low GWG had the lowest abundance of distal gut Bacteroides and appreciably higher relative abundance of a consortia of vaginal taxa including Atopobium, Gardnerella, Prevotella, and Sneathia. CONCLUSION: These results contribute new evidence showing that GWG in combination with obesity and obesity class is associated with an altered distal gut and vaginal composition early in pregnancy among AA women.

Recent advancement in the discovery and development of COX-2 inhibitors: Insight into biological activities and SAR studies (2008-2019).

Cyclooxygenase-2 is a very important physiological enzyme playing key roles in various biological functions especially in the mechanism of pain and inflammation, among other roles, making it a molecule of high interest to the pharmaceutical community as a target. COX 2 enzyme is induced only during inflammatory processes or cancer and reflects no role in the guarding stomach lining. Thus, selective COX-2 inhibition can significantly reduce the adverse effects including GI tract damage and hepatotoxic effects of traditional NSAIDs like aspirin, ibuprofen, etc. Recent developments on COX-2 inhibitors is primarily focused on improving the selectivity index of the drug towards COX-2 along with enhancing the potency of the drug by modifying the scaffolds of Coxibs currently in the market like Celecoxib, Indomethacin, Oxaprozin, etc. We have reported the progress on new COX-2 inhibitors in the last decade (2008-2019) focussing on five heterocyclic rings- Pyrazole, Indole, Oxazole, Pyridine and Pyrrole. The addition of various moieties to these core rings and their structure-activity relationship along with their molecular modelling data have been explored in the article. This review aims to aid medicinal chemists in the design and discovery of better COX-2 inhibitors constructed on these five heterocyclic pharmacophores.