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Fulltext Robust EEG/MEG Based Functional Connectivity with the Envelope of the Imaginary Coherence: Sensor Space Analysis

Sanchez Bornot JM, Wong-Lin K, Ahmad AL, Prasad G

Brain Topogr, 2018 11;31(6):895-916.
PMID: 29546509 DOI: 10.1007/s10548-018-0640-0

The brain's functional connectivity (FC) estimated at sensor level from electromagnetic (EEG/MEG) signals can provide quick and useful information towards understanding cognition and brain disorders. Volume conduction (VC) is a fundamental issue in FC analysis due to the effects of instantaneous correlations. FC methods based on the imaginary part of the coherence (iCOH) of any two signals are readily robust to VC effects, but neglecting the real part of the coherence leads to negligible FC when the processes are truly connected but with zero or π-phase (modulus 2π) interaction. We ameliorate this issue by proposing a novel method that implements an envelope of the imaginary coherence (EIC) to approximate the coherence estimate of supposedly active underlying sources. We compare EIC with state-of-the-art FC measures that included lagged coherence, iCOH, phase lag index (PLI) and weighted PLI (wPLI), using bivariate autoregressive and stochastic neural mass models. Additionally, we create realistic simulations where three and five regions were mapped on a template cortical surface and synthetic MEG signals were obtained after computing the electromagnetic leadfield. With this simulation and comparison study, we also demonstrate the feasibility of sensor FC analysis using receiver operating curve analysis whilst varying the signal's noise level. However, these results should be interpreted with caution given the known limitations of the sensor-based FC approach. Overall, we found that EIC and iCOH demonstrate superior results with most accurate FC maps. As they complement each other in different scenarios, that will be important to study normal and diseased brain activity.
Ultrasound mediated efficient synthesis of new 4-oxoquinazolin-3(4H)-yl)furan-2-carboxamides as potent tyrosinase inhibitors: Mechanistic approach through chemoinformatics and molecular docking studies

Dige NC, Mahajan PG, Raza H, Hassan M, Vanjare BD, Hong H, et al.

Bioorg Chem, 2019 11;92:103201.
PMID: 31445195 DOI: 10.1016/j.bioorg.2019.103201

We have carried out the synthesis of new 4-oxoquinazolin-3(4H)-yl)furan-2-carboxamide derivatives by the reaction between isatoic anhydride, 2-furoic hydrazide and substituted salicylaldehydes in ethanol: water (5:5 v/v) solvent system using p-TSA as a catalyst under ultrasound irradiation at room temperature. The structures of newly synthesized compounds were confirmed through spectral techniques such as IR, 1H NMR, 13C NMR, and LCMS. The important features of this protocol include simple and easy workup procedure, reaction carried out at ambient temperature, use of ultrasound and high yield of oxoquinazolin-3(4H)-yl)furan-2-carboxamides in short reaction time. The synthesized compounds 4a-4j were screened against tyrosinase enzyme and all these compounds found to be potent inhibitors with much lower IC50 value of 0.028 ± 0.016 to 1.775 ± 0.947 µM than the standard kojic acid (16.832 ± 1.162 µM). The kinetics mechanism for compound 4e was analyzed by Lineweaver-Burk plots which revealed that compound inhibited tyrosinase non-competitively by forming an enzyme-inhibitor complex. Along with this all the synthesized compounds (4a-4j) were scanned for their DPPH free radical scavenging ability. The outputs received through in vitro and in silico analysis are coherent to the each other with good binding energy values (kcal/mol) posed by synthesized ligands.
Synthesis and characterization of new 4H-chromene-3-carboxylates ensuring potent elastase inhibition activity along with their molecular docking and chemoinformatics properties

Dige NC, Mahajan PG, Raza H, Hassan M, Vanjare BD, Hong H, et al.

Bioorg Chem, 2020 07;100:103906.
PMID: 32422387 DOI: 10.1016/j.bioorg.2020.103906

A new series of 4H-chromene-3-carboxylate derivatives were synthesized using multicomponent reaction of salicylaldehyde, ethyl acetoacetate and dimedone in ethanol with K3PO4 as a catalyst at 80 °C. The structures of all newly synthesized compounds were confirmed by spectral techniques viz. IR, 1H NMR, 13C NMR, and LCMS analysis. The newly synthesized compounds 4a to 4j were screened against elastase enzyme. Interestingly, all these compounds found to be potent elastase inhibitors with much lower IC50 value. The compound 4b was found to be most potent elastase inhibitor (IC50 = 0.41 ± 0.01 µM) amongst the synthesized series against standard Oleanolic Acid (IC50 value = 13.45 ± 0.0 µM). The Kinetics mechanism for compound 4b was analyzed by Lineweaver-Burk plots which revealed that compound inhibited elastase competitively by forming an enzyme-inhibitor complex. Along with this, all the synthesized compounds (4a - 4j) exhibits excellent DPPH free radical scavenging ability. The inhibition constant Ki for compound 4b was found to be 0.6 µM. The computational study was comprehensible with the experimental results with good docking energy values (Kcal/mol). Therefore, these molecules can be considered as promising medicinal scaffolds for the treatment of skin-related maladies.
Safety and efficacy of Ensifentrine in COPD: A Systemic Review and Meta-analysis

Yappalparvi A, Balaraman AK, Padmapriya G, Gaidhane S, Kaur I, Lal M, et al.

Respir Med, 2024 Nov 16.
PMID: 39557208 DOI: 10.1016/j.rmed.2024.107863

BACKGROUND: Chronic obstructive pulmonary disease (COPD) significantly impacts global health due to persistent airflow limitation and inflammation. Despite standard therapies, symptoms persist. Ensifentrine, targeting both bronchoconstriction and inflammation as a dual phosphodiesterase 3 and 4 inhibitor, offers a promising therapeutic advancement for COPD management. This meta-analysis evaluates the safety and efficacy of ensifentrine in improving lung function, dyspnea, and quality of life in COPD patients.
METHODS: We searched PubMed, Embase, and Web of Science through August 2024 for randomized controlled trials evaluating ensifentrine in COPD patients over a minimum of four weeks. Data extraction and screening utilized Knowledge software, and meta-analyses were performed using R v4.4 with a random-effects model.
RESULTS: From 206 studies identified, four met our inclusion criteria. Ensifentrine improved FEV1 significantly at a dose of 3 mg (LS mean difference: 40.90 mL; 95% CI: 19.65-62.15). It also improved dyspnea as measured by the Transition Dyspnea Index (TDI) (LS mean difference: 0.91; 95% CI: 0.61-1.21) and quality of life according to the St. George's Respiratory Questionnaire-C (SGRQ-C) scores (LS mean difference: -1.92; 95% CI: -3.28 to -0.55). Safety profiles were comparable between the ensifentrine and placebo groups, with no significant increase in treatment-emergent adverse events (TEAEs) (RR: 1.02; 95% CI: 0.94-1.10).
CONCLUSION: Ensifentrine significantly enhances lung function, reduces dyspnea, and improves quality of life in COPD patients, especially at a 3 mg dose. These benefits, coupled with a stable safety profile, support its use as an adjunctive therapy in COPD management.
Proteostasis disruption and senescence in Alzheimer's disease pathways to neurodegeneration

Thapa R, Ahmad Bhat A, Shahwan M, Ali H, PadmaPriya G, Bansal P, et al.

Brain Res, 2024 Dec 15;1845:149202.
PMID: 39216694 DOI: 10.1016/j.brainres.2024.149202

Alzheimer's Disease (AD) is a progressive neurological disease associated with behavioral abnormalities, memory loss, and cognitive impairment that cause major causes of dementia in the elderly. The pathogenetic processes cause complex effects on brain function and AD progression. The proper protein homeostasis, or proteostasis, is critical for cell health. AD causes the buildup of misfolded proteins, particularly tau and amyloid-beta, to break down proteostasis, such aggregates are toxic to neurons and play a critical role in AD pathogenesis. The rise of cellular senescence is accompanied by aging, marked by irreversible cell cycle arrest and the release of pro-inflammatory proteins. Senescent cell build-up in the brains of AD patients exacerbates neuroinflammation and neuronal degeneration. These cells senescence-associated secretory phenotype (SASP) also disturbs the brain environment. When proteostasis failure and cellular senescence coalesce, a cycle is generated that compounds each other. While senescent cells contribute to proteostasis breakdown through inflammatory and degradative processes, misfolded proteins induce cellular stress and senescence. The principal aspects of the neurodegenerative processes in AD are the interaction of cellular senescence and proteostasis failure. This review explores the interconnected roles of proteostasis disruption and cellular senescence in the pathways leading to neurodegeneration in AD.