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Ten novel benzylidine‐N‐phenylhydrazine‐1‐carboxamide derivatives (7 a–7 j) were synthesized in three steps and evaluated for their tyrosinase inhibitory and antioxidant activities. The spectrophotometric method with L–DOPA as a substrate was used to determine tyrosinase inhibitory activities, and a DPPH assay was used to evaluate antioxidant properties. Among the synthesized compounds, compound 7 c with an ethyl substitution on the C2‐N‐phenylacetamide ring showed the highest tyrosinase‐inhibition activity (IC50=4.36±1.58 μM), which was comparable with that of standard kojic acid (IC50=16.34±1.93 μM). Compounds (7 d) and (7 e) showed potent antioxidant activities (EC50=52.11±4.18 and 92.47±3.32 μM, respectively), which were comparable to those of quercetin. The study of the interactions and binding modes of the tested compounds was accomplished with molecular docking. Docking results corroborated that the active inhibitors were well placed in the mushroom tyrosinase enzyme's active site. [ABSTRACT FROM AUTHOR]

Neuroblastoma (NB) is the third most prevalent tumor that mostly influences infants and young children. Although different treatments have been developed for the treatment of NB, high‐risk patients have been reported to have low survival rates. Currently, long noncoding RNAs (lncRNAs) have shown an attractive potential in cancer research and a party of investigations have been performed to understand mechanisms underlying tumor development through lncRNA dysregulation. Researchers have just newly initiated to exhibit the involvement of lncRNAs in NB pathogenesis. In this review article, we tried to clarify the point we stand with respect to the involvement of lncRNAs in NB. Moreover, implications for the pathologic roles of lncRNAs in the development of NB have been discussed. It seems that some of these lncRNAs have promising potential to be applied as biomarkers for NB prognosis and treatment. [ABSTRACT FROM AUTHOR]

We investigated the frequency of brain fog in a large cohort of patients with documented coronavirus disease‐2019 (COVID‐19) who have survived the illness. We also scrutinized the potential risk factors associated with the development of brain fog. Adult patients (18–55 years of age), who were referred to the healthcare facilities anywhere in Fars province from February 19, 2020 to November 20, 2020 were included. All patients had a confirmed COVID‐19 diagnosis. In a phone call, at least 3 months after their discharge from the hospital, we obtained their current information. A questionnaire was specifically designed for data collection. In total, 2696 patients had the inclusion criteria; 1680 (62.3%) people reported long COVID syndrome (LCS). LCS‐associated brain fog was reported by 194 (7.2%) patients. Female sex (odds ratio [OR]: 1.4), respiratory problems at the onset (OR: 1.9), and intensive care unit (ICU) admission (OR: 1.7) were significantly associated with reporting chronic post‐COVID "brain fog" by the patients. In this large population‐based study, we report that chronic post‐COVID "brain fog" has significant associations with sex (female), respiratory symptoms at the onset, and the severity of the illness (ICU admission). [ABSTRACT FROM AUTHOR]

The complex nature of macromolecularinteractions usually makesit very hard to identify the molecular-level mechanisms that ultimatelydictate the result of these interactions. This is especially evidentin the case of biological systems, where the complex interaction ofmolecules in various situations may be responsible for driving biomolecularinteractions themselves but also has a broader effect at the celland/or tissue level. This review will endeavor to further the understandingof biomolecular interactions utilizing the isothermal titration calorimetry(ITC) technique for thermodynamic characterization of two extremelyimportant biomaterial systems, viz., peptide self-assembly and nonfoulingpolymer-modified surfaces. The advantages and shortcomings of thistechnique will be presented along with a thorough review of the recentapplication of ITC to these two areas. Furthermore, the controversiesassociated with the enthalpy–entropy compensation effect aswell as thermodynamic equilibrium state for such interactions willbe discussed. [ABSTRACT FROM AUTHOR]

Ionic self-complementary peptidesare considered an important classof self-assembling peptides. In particular, RADARADARADARADA(RADA4) is well-known to form a relatively regular nanofiberstructure that has been primarily studied in terms of its physicochemicalproperties, as related to its biomedical applications. However, themolecular level interactions that are involved in promoting the self-assemblyof this peptide into nanofibers have not been fully elucidated. Herein,a thermodynamic analysis of the influences of peptide chemistry uponself-assembly is discussed for RADA4, RADA4-K5, and RADA4-S5. The regular nanofiberstructure of the assembled peptides makes it a good candidate forisothermal titration calorimetry (ITC) studies for determining thepropensity for self-assembly, the critical assembly concentration(CAC), and the role hydration and ion content play in the assemblyof these peptides. First, solutions containing only RADA4-K5did not self-assemble; illustrating even slight alterationsin the asymmetric terminal amino acid chemistry affects assembly.The CAC of the remaining self-assembling peptides was between ∼0.1and ∼0.15 mM. Interestingly, we found that self-assembly wasentropically driven with hydrophobic forces being the main drivingforce for RADA4and hydrogen bonding for RADA4-S5. The role of water molecules and counterions in self-assemblywas also highlighted: assembly of RADA4led to desolvationof interfacial surfaces, whereas the net number of water moleculesin the assembled complex increased upon RADA4-S5self-assembly. Moreover, it was found that counterions did not seemto contribute significantly to self-assembly: a result in contrastto current concepts regarding the role of electrostatic interactionsin self-assembly of RADA4-like peptides. A molecular levelunderstanding of peptide self-assembly will allow for further engineeringof peptides for a vast array of biomedical applications. [ABSTRACT FROM AUTHOR]

Background: Recently, people have recognized the post-acute phase symptoms of the COVID-19. We investigated the long-term symptoms associated with COVID-19, (Long COVID Syndrome), and the risk factors associated with it. Methods: This was a retrospective observational study. All the consecutive adult patients referred to the healthcare facilities anywhere in Fars province from 19 February 2020 until 20 November 2020 were included. All the patients had a confirmed COVID-19 diagnosis. In a phone call to the patients, at least three months after their discharge from the hospital, we obtained their current information. The IBM SPSS Statistics (version 25.0) was used. Pearson Chi square, Fisher's exact test, t test, and binary logistic regression analysis model were employed. A P value of less than 0.05 was considered to be significant. Results: In total, 4,681 patients were studied, 2915 of whom (62.3%) reported symptoms. The most common symptoms of long COVID syndrome were fatigue, exercise intolerance, walking intolerance, muscle pain, and shortness of breath. Women were more likely to experience long-term COVID syndrome than men (Odds Ratio: 1,268; 95% Confidence Interval: 1,122-1,432; P=0.0001), which was significant. Presentation with respiratory problems at the onset of illness was also significantly associated with long COVID syndrome (Odds Ratio: 1.425; 95% Confidence Interval: 1.177-1.724; P=0.0001). A shorter length of hospital stay was inversely associated with long COVID syndrome (Odds Ratio: 0.953; 95% Confidence Interval: 0.941-0.965; P=0.0001). Conclusion: Long COVID syndrome is a frequent and disabling condition and has significant associations with sex (female), respiratory symptoms at the onset, and the severity of the illness. [ABSTRACT FROM AUTHOR]

Tyrosinase, a metalloprotein enzyme, plays a crucial role in melanin synthesis by hydroxylating L-tyrosine to L-dopa. However, the accumulation of melanin can lead to hyperpigmented spots, raising aesthetic concerns. In this study, we developed a pipeline to repurpose FDA-approved drugs as potential tyrosinase inhibitors. A structure-based screening study was conducted using 1,650 drugs to identify probable inhibitors based on binding energies. From the cluster analysis of binding interaction profiles, 16 compounds were selected as candidates. Montelukast emerged as the final candidate due to its favorable ADME properties. Bioassay evaluation revealed an IC50 value of 14.79±0.87 μM for Montelukast, compared to kojic acid (IC50=31.02±2.01 μM). Molecular dynamics simulation and g_MMPBSA free energy calculation studies were performed for the Tyrosinase-Montelukast complex. These findings enhance our understanding of Tyrosinase-Montelukast interactions and underscore Montelukast's potential as a tyrosinase inhibitor. This could have implications in dermatological applications and beyond, suggesting Montelukast as a promising candidate for further development in this regard., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Background: Arteriovenous fistula (AVF), permanent catheter (PC), and vascular graft are three vascular access types used for hemodialysis procedure. Due to insufficient reliable information on the comparison between AVF and PC, this study was conducted to compare AVF and PC regarding dialysis adequacy., Materials and Methods: This prospective study was carried out from March, 2013 to September, 2013. In this study, 76 hemodialysis patients were enrolled and assigned to two unequal groups of AVF and PC. Before and after the dialysis session, blood samples were taken for laboratory examinations and measurement of urea reduction ratio (URR) and Kt/V. The patients were followed up for six months, and then laboratory examinations were repeated., Results: Of the 76 hemodialysis patients, 30 had AVF and others PC. During the 6-month follow-up, 24 patients in PC group but only one patient in AVF group showed infection ( P = 0.006), while in each group, three cases of thrombosis were seen ( P = 0.58); however, catheter dysfunction was seen in 13 patients of PC group but no patients of AVF group ( P = 0.004). There was no difference between the two groups in Kt/V and URR at the beginning of the study; however, after six months, Kt/V and URR were greater in AVF group ( P < 0.05)., Conclusions: In addition to some advantages of AVF over PC, such as lower rate of infection and thrombosis, we also found better dialysis adequacy in AVF group. We recommend that AVF be created in all of patients with chronic kidney disease who are candidates for hemodialysis., Competing Interests: There are no conflicts of interest.