Novel Deliberately Sensitive and Selective Tetrahydrozoline Voltammetric Sensors Integrated with a Copper Oxide Nanoparticle/Zeolite Platform.

The present study introduced a novel disposable screen-printed carbon electrodes (SPCEs) modified with copper oxide/zeolite nanostructures for eco-friendly selective differential pulse voltammetric quantification of tetrahydrozoline (THZ) in eyedrop samples and biological fluids. Modification of the electrode matrix with copper oxide nanoparticles/zeolite nanostructures (CuONPs/ZY) with their effective and synergistic electrocatalytic activity enhanced the electrode performance against electrooxidation of THZ at 0.960 V in BR at pH 9.0 with a diffusion-controlled reaction mechanism. The tentative oxidation mechanism based on molecular orbital calculations postulates the oxidation of THZ molecules through oxidation of a nitrogen atom five-membered ring and the participation of two electrons/protons in the electrode reaction. Linear calibration curves were illustrated within a wide THZ concentration range from 0.24 to 57.2 µg mL-1 recording a limit of detection (LOD) value of 0.0799 µg mL-1. The CuONPs/ZY/SPEs exhibited improved performance compared with the sole reported THZ sensor-based gold film-plated carbon paste electrodes, in addition to their high reproducibility of fabrication and measurement and prolonged shelf lifetime. Tetrahydrozoline was successfully assayed in the presence of excipients, degradation products, and chloramphenicol. The presented voltammetric sensor can be considered as an eco-friendly and reliable analytical approach for monitoring THZ residues in eye drop samples and biological fluids with high recovery compared with the official pharmacopeial analytical protocol. The presented sensors were assessed according to an EcoScale tool and also compared with the reported THZ sensor.

Evaluation of Xpert MTB/RIF Ultra for the Diagnosis of Extrapulmonary Tuberculosis: A Retrospective Analysis in Saudi Arabia.

The incidence of extrapulmonary tuberculosis (EPTB) in low- and middle-income countries, as well as, high-income countries has increased over the last two decades. The acid-fast bacillus (AFB) smear test is easy to perform and cost-effective with a quick turnaround time but the test has low sensitivity. Culture remains the gold standard for detecting TB; however, it has low sensitivity and slow bacterial growth patterns, as it may take up to 6 to 8 weeks to grow. Therefore, a rapid detection tool is crucial for the early initiation of treatment and ensuring an improved therapeutic outcome. Here, the Xpert Ultra system was developed as a nucleic acid amplification technique to accelerate the detection of MTB in paucibacillary clinical samples and endorsed by the World Health Organization. From March 2020 to August 2021, Xpert Ultra was evaluated for its sensitivity and specificity against EPTB and compared with those of the routinely used Xpert, culture, and AFB tests in 845 clinical samples in Saudi Arabia. The results indicate the overall sensitivity and specificity of Xpert Ultra to be 91% and 95%, respectively, compared with the Xpert (82% and 99%, respectively) and AFB smear (18% and 100%, respectively) tests. The results also indicated that despite the low microbial loads that were categorized as trace, very low, or low on Xpert Ultra, yet, complete detection was achieved with some sample types (i.e., 100% detection). Consequently, Xpert Ultra has great potential to replace conventional diagnostic approaches as a standard detection method for EPTB.

Novel Iron Oxide Nanoparticle-Fortified Carbon Paste Electrode for the Sensitive Voltammetric Determination of Atomoxetine.

Herein, the fabrication and full characterization of a novel atomoxetine (ATX) voltammetric carbon paste electrode (CPE) fortified with iron oxide nanoparticles (FeONPs) is demonstrated. Modification of the carbon paste matrix with the metallic oxide nanostructure provides proper electrocatalytic activity against the oxidation of ATX molecules at the carbon paste surface, resulting in a noticeable improvement in the performance of the sensor. At the recommended pH value, ATX recorded an irreversible anodic peak at 1.17 V, following a diffusion-controlled reaction mechanism. Differential pulse voltammograms exhibited peak heights linearly correlated to the ATX content within a wide concentration range from 45 to 8680 ng mL-1, with the limit of detection reaching 11.55 ng mL-1. The electrooxidation mechanism of the ATX molecule was proposed to be the oxidation of the terminal amino group accompanied by the transfer of two electrons and two protons. The fabricated FeONPs/CPE sensors exhibited enhanced selectivity and sensitivity and therefore can be introduced for voltammetric assaying of atomoxetine-indifferent pharmaceutical and biological samples in the presence of its degradation products and metabolites.

Efficacy and Safety of Bedside Removal of Tunnelled Hemodialysis Catheter by Noninterventional Nephrologists among Adult Patients in the King Abdulaziz University Hospital Hemodialysis Centre in Jeddah: A Retrospective Cohort Study.

This study aimed to assess the efficacy and safety of bedside removal of tunnelled hemodialysis catheter (TDC) by noninterventional nephrologists among adult patients. It is a retrospective study that involved 53 patients from March 2020 to February 2022 at the King Abdulaziz University Hospital (KAUH) Hemodialysis Centre in Jeddah, Saudi Arabia. Of the 53 participants, 60.4% were male and 40.6% female, and their mean age was 50.94 ± 18.89 years. The most common comorbidities were hypertension (HTN) in 47 (88.7%), diabetes mellitus (DM) in 24 (45.3%), and DM and HTN together in 23 (43.4%) patients. The most common site of TDC removal was the right internal jugular vein (77.4%). In 84.9% of the cases, the TDC was removed as an inpatient procedure, and in the majority of the cases (64.2%), the TDC was removed by a noninterventional nephrologist. The most common reasons for TDC removal were sepsis or clinical concerns for infection (64.2%) and TDC not needed (20.8%) due to recovery of the renal function or access maturation. Most patients (96.2%) suffered no complications; only one of 34 (%) patients with catheter removal by a noninterventional nephrologist had bleeding, which required more observation and monitoring before discharge on the same day. Our study revealed that the bedside TDC removal was well tolerated with a minimal complication rate.

Synthesis of (tricyanofuran-3-ylmethylene)hydrazinyl thiazole-containing chromophore: A study of its photophysical properties, solvatochromism, and TD-DFT computations.

The chromophore 2-2-(3-cyano-5,5-dimethyl-4-((2-[thiazol-2-yl]hydrazono)methyl)-furan-2(5H)-ylidene)malononitrile (TzHTCF) was prepared by diazo-coupling of diazotized 2-aminothiazole with 3-cyano-2-(dicyanomethylene)-4,5,5-trimethylfuran (TCF). The TzHTCF absorption solvatochromism, in different polarity solvents, demonstrated a ΔEmax = +4.74 in which the positive sign implied the occurrence of a red shift and the TzHTCF lowest excited state was more polar than its ground state. In addition, the TzHTCF fluorescence spectrum produced a λem in the 416-670 nm range and was more dependent on the solvent polarity than the absorption λmax , despite both exhibiting a red shift of 24 and 254 nm, respectively. To discover the Stokes shift ( ∆ ν ¯ ) behaviour of the TzHTCF derivative, Lippert-Mataga and linear solvation-energy relationship (LSER) formulations were utilized in which the LSER approach displayed better results than the Lippert-Mataga method (R2 = 0.9931). Furthermore, the LSER showed that the absorption and fluorescence solvatochromic behaviours were dependent on the solvent's hydrogen-bond donor (α) and acceptor (ß), along with the solvent's polarizability (π*). Moreover, DFT calculations showed that TzHTCF has a planar configuration and its simulated absorption and emission spectra in dimethyl sulphoxide revealed that λmax primarily originated from the HOMO→LUMO and HOMO-1→LUMO transitions, respectively.

Synthesis and characterization of new thiazole-based Co(II) and Cu(II) complexes; therapeutic function of thiazole towards COVID-19 in comparing to current antivirals in treatment protocol.

Two thiazole-based complexes were prepared from Co(II) and Cu(II) ions. The new ligand and its complexes were fully characterized by analytical and spectral techniques. The ligand behaved as a neutral tridentate in its keto-form towards the metals via O(8), O(10) and O(18) atoms. This was suggested based on the lower shift of υ(CH[bond, double bond]O), υ(C[bond, double bond]O)amide and υ(C-O) vibrations. The electronic transitions in Co(II)-HL and Cu(II)-HL complexes displayed d-d- transitions which belong to 4T1g→4A2g(F) & 4T1g(F)→4T1g (P) and 2Eg →2T2g, in the two complexes, respectively. ESR spectrum of Cu(II)-HL complex displayed g-factor by the following order; g//(2.1740)>g⊥(2.0935)>2.0023, which agrees with octahedral geometry. The geometry optimization was executed by DFT/B3LYP method under valence double zeta polarized basis set (6-31G*), to confirm the structural forms and the mode of bonding. The orientation and the charges of O(8), O(10) and O(18) atoms, support the coordination of the ligand in its keto-form with the metal ions. Pharmacophore profiles were obtained regarding thiazole ligand and other recommended drugs (arbidol, avigan and idoxuridine) that used in treatment protocol of COVID-19 pandemic. Also, query was run in MolPort-library to obtain antiviral analogues, to broaden the search for an effective treatment. Three analogues were obtained for arbidol, avigan and idoxuridine drugs, which have the following numbers; MolPort-047-605-644, MolPort-004-768-508 and MolPort-028-750-709, respectively. Moreover, molecular docking was carried out to obtain all interaction details and rank the efficiency of thiazole compound versus the three antivirals in their interaction with the two COVID-19 proteins. The outcomes suggested the significant antiviral activity of idoxuridine and thiazole (enol-form), which not reach to eliminate the pandemic exactly. While, arbidol and avigan did not have an effective antiviral role, although they still used in COVID-19 treatment protocol.

Spectral, Molecular Modeling, and Biological Activity Studies on New Schiff's Base of Acenaphthaquinone Transition Metal Complexes.

The newly synthesized Schiff's base derivative, N-allyl-2-(2-oxoacenaphthylen-1(2H)-ylidene)hydrazine-1-carbothioamide, has been characterized by different spectral techniques. Its reaction with Co(II), Ni(II), and Zn(II) acetate led to the formation of 1 : 1 (M:L) complexes. The IR and NMR spectral data revealed keto-thione form for the free ligand. On chelation with Co(II) and Ni(II), it behaved as mononegative and neutral tridentate via O, N1, and S donors, respectively, while it showed neutral bidentate mode via O and N1 atoms with Zn(II). The electronic spectra indicated that all the isolated complexes have an octahedral structure. The thermal gravimetric analyses confirmed the suggested formula and the presence of coordinated water molecules. The XRD pattern of the metal complexes showed that both Co(II) and Ni(II) have amorphous nature, while Zn(II) complex has monoclinic crystallinity with an average size of 9.10 nm. DFT modeling of the ligand and complexes supported the proposed structures. The calculated HOMO-LUMO energy gap, ΔEH-L, of the ligand complexes was 1.96-2.49 eV range where HAAT < Zn(II) < Ni(II) < Co(II). The antioxidant activity investigation showed that the ligand and Zn(II) complex have high activity than other complexes, 88.5 and 88.6%, respectively. Accordingly, the antitumor activity of isolated compounds was examined against the hepatocellular carcinoma cell line (HepG2), where both HAAT and Zn(II) complex exhibited very strong activity, IC50 6.45 ± 0.25 and 6.39 ± 0.18 µM, respectively.

Aurintricarboxylic acid and its metal ion complexes in comparative virtual screening versus Lopinavir and Hydroxychloroquine in fighting COVID-19 pandemic: Synthesis and characterization.

The salt of Aurintricarboxylic acid (ATA) was utilized in this study to synthesize new alkaline earth metal ion complexes. The analytical results proposed the isolation of mononuclear (Sr+2&Ba+2) and binuclear complexes (Mg+2&Ca+2). These complexes were analyzed by available analytical and spectral techniques. The tetrahedral geometry was suggested for all complexes (SP3) through bidentate binding mode of ligand with each central atom. UV-Vis spectra reveal the influence of L â†’ M charge transfer and the estimated optical band gap mostly appeared close to that for known semiconductors. XRD, SEM and TEM studies were executed for new complexes and reflects the nano-crystallinity and homogeneous morphology. The structural forms of ATA and its complexes were optimized by DFT/B3LYP under 6-31G and LANL2DZ basis sets. The output files (log, chk &fchk) were visualized on program screen and according to numbering scheme, many physical features were obtained. It is worthy to note that, a virtual simulation for the inhibition affinity towards COVID-19 proteins as proactive study before the actual application, was done for ATA and its complexes. This was done in addition to drugs currently applied in curing (Hydroxychloroquine & Lopinavir), for comparison and recommendation. Drug-likeness parameters were obtained to evaluate the optimal pharmacokinetics to ensure efficacy. Furthermore, simulated inhibition for COVID-19 cell-growth, was conducted by MOE-docking module. The negative allosteric binding mode represents good inhibitory behavior of ATA, Ba(II)-ATA complex and Lopinavir only. All interaction outcomes of Hydroxychloroquine drug reflect unsuitability of this drug in treating COVID-19. On the other hand, there is optimism for ATA and Lopinvir behaviors in controlling COVID-19 proliferation.

Luminescence feature of new 3,6-di(thiazolidin-5-one-2-yl)-carbazole derivative: synthesis, photophysical properties, density functional theory studies, and crystal shape effect.

A new carbazole chromophore conjugated with substituted thiazolidine-4-one (CzPT) was synthesized by applying the Knoevenagel reaction between 3,6-diformyl-N-hexylcarbazole and ethyl 2-aceto-2-(5-oxo-3-phenylthiazolidin-2-ylidene)acetate. The chemical structure of the new derivative (CzPT) was elucidated by spectral studies. The CzPT absorption spectra in different solvents exhibited a red shift for λmax by increasing solvent polarity. Bands at 430-474 nm appeared and were attributed to intramolecular charge transfer with high π-π* characteristics. CzPT fluorescence spectra exhibited a red shift after increasing the solvent polarity. To understand the Stokes' shift ( ∆ ν ¯ ) behaviour of the CzPT derivative referring to the polarity of solvents, Lippert-Mataga and linear solvation-energy relationship (LSER) models were employed in which the LSER exhibited respectable results compared with Lippert-Mataga (r2 = 0.9707). Moreover, time-dependent density functional theory absorption spectra in hexane and dimethylformamide showed that λmax had a major contribution in the highest occupied molecular orbital to lowest unoccupied molecular orbital transition in both solvents. In addition, the reduced uniformity of crystal features may lead to dislocation or anomalous arrangement of crystals with irregular spacing, which automatically enhances the optical properties of such crystals.

Evaluation of Awareness, Knowledge, and Attitudes Towards Basic Life Support Among Non-Medical Students at Two Academic Institutions in Jeddah, Saudi Arabia.

BACKGROUND: Cardiac arrests are a leading cause of mortality in Saudi Arabia. Prompt and quick intervention using early cardiopulmonary resuscitation (CPR) can be a life-saving strategy. Sufficient knowledge and awareness regarding CPR are important in initial care, particularly during an out-of-hospital cardiac arrest. We aim to assess the knowledge, awareness, and attitude toward CPR among the students of King Abdulaziz University and Jeddah University. MATERIALS AND METHODS: A descriptive, cross-sectional study design with a sample of 1053 non-medical students, regardless of their academic year, was conducted from May to July 2019 at both universities. Data were analyzed through chi-square and analysis of variance where a P-value <0.05 was considered statistically significant. RESULTS: Out of 1053 students, 28.7% received CPR training. Also, the majority of the subjects were female 71%. The science department provided the largest response. Results showed that chest pain was the most observed early sign of cardiac arrest among participants by a percentage of 84.6. Majority of the participants (90.9%) felt no hesitation in performing early CPR on a family member. Additionally, committing a mistake was the most feared factor that deterred students from performing CPR. CONCLUSION: Knowledge and awareness of CPR among non-medical university students were poor, despite positive attitudes toward it. Integrating mandatory CPR courses in the orientation and in the first year of the undergraduate curriculum could increase awareness and improve the outcomes of out-of-hospital cardiac arrest (OHCA).

Vici syndrome with pathogenic homozygous EPG5 gene mutation: A case report and literature review.

RATIONALE: Vici syndrome (VICIS) is a rare, autosomal recessive neurodevelopmental disorder with multisystem involvement characterized by agenesis of the corpus callosum, congenital cataracts, cardiomyopathy, combined immunodeficiency, significant developmental delay, and hypopigmentation and in some cases loss of hearing. It is caused by mutations in Ectopic P-granules protein 5 gene, which is responsible for regulating autophagy activity. PATIENT CONCERN: We report a 6-month-old Saudi female patient who was the second-born baby of first cousins. She was born by normal spontaneous vertex vaginal delivery. Parents noticed that she had global developmental delay and recurrent hospital admissions due to chest infections. DIAGNOSIS: Brain magnetic resonance imaging showed brain atrophy with corpus callosum agenesis. Ophthalmology examination revealed bilateral congenital cataract. Molecular genetic testing identified the pathogenic homozygous variant c.4751T>A p. (Leu1584*) on exon 27 of the EPG5 gene and confirmed the diagnosis of Vici syndrome. INTERVENTIONS: Supportive multidisciplinary care plan was initiated to this untreatable syndrome. OUTCOMES: The patient died at the age of 6 months due to sepsis with uncompensated septic shock. LESSONS: VICIS is a rare untreatable disorder with worldwide distribution. High index of suspicion is needed to diagnose it and family genetic counselling is crucial.

Role of peroxiredoxin of the AhpC/TSA family in antioxidant defense mechanisms of Francisella tularensis.

Francisella tularensis is a Gram-negative, facultative intracellular pathogen and the causative agent of a lethal human disease known as tularemia. Due to its extremely high virulence and potential to be used as a bioterror agent, F. tularensis is classified by the CDC as a Category A Select Agent. As an intracellular pathogen, F. tularensis during its intracellular residence encounters a number of oxidative and nitrosative stresses. The roles of the primary antioxidant enzymes SodB, SodC and KatG in oxidative stress resistance and virulence of F. tularensis live vaccine strain (LVS) have been characterized in previous studies. However, very fragmentary information is available regarding the role of peroxiredoxin of the AhpC/TSA family (annotated as AhpC) of F. tularensis SchuS4; whereas the role of AhpC of F. tularensis LVS in tularemia pathogenesis is not known. This study was undertaken to exhaustively investigate the role of AhpC in oxidative stress resistance of F. tularensis LVS and SchuS4. We report that AhpC of F. tularensis LVS confers resistance against a wide range of reactive oxygen and nitrogen species, and serves as a virulence factor. In highly virulent F. tularensis SchuS4 strain, AhpC serves as a key antioxidant enzyme and contributes to its robust oxidative and nitrosative stress resistance, and intramacrophage survival. We also demonstrate that there is functional redundancy among primary antioxidant enzymes AhpC, SodC, and KatG of F. tularensis SchuS4. Collectively, this study highlights the differences in antioxidant defense mechanisms of F. tularensis LVS and SchuS4.

Facile Synthesis and Photoactivity of Merocyanine-Photoacid Polymers.

In recent years, merocyanine photoacids have been utilized to control various chemical processes using visible light and have found applications in materials, energy, and biomedical areas. Molecular merocyanine photoacids are commonly used in the previous works. Covalently linking the photoacids to polymers improves their compatibility with different media, avoids leakage problems, and allows a localized proton concentration to be produced. However, the phenolic and indolinium moieties of the photoacids make them difficult to be polymerized with common methods. In this work, the monomer of a merocyanine photoacid is converted to a spiropyran in situ by adding trimethylamine to a dimethyl sulfoxide (DMSO) solution of the monomer. Free radical polymerization yields the polymers of the spiropyran, which is acidified to regenerate the photoacid. The photoacid polymers prepared show good solubility, photoacidity, and reversibility. Irradiating a thin film of a photoacid polymer doped with methyl orange through a mask copies the pattern of the mask to the film. The pattern can be erased by heating the film at 80 °C for 10 min, and a new pattern is created by irradiation through a different mask.