The widely distributed granitic intrusions in the Nubian Shield can provide comprehensive data for understanding its crustal evolution. We present new bulk-rock geochemistry and isotopic (zircon U-Pb ...and Lu-Hf) data from the Haweit granodiorites in the Gabgaba Terrane (NE Sudan). The dated zircons presented a 206Pb/238U Concordia age of 718.5 ± 2.2 Ma, indicating that they crystallized during the Cryogenian. The granodiorites contain both biotite and amphibole as the main mafic constituents. The samples exhibit metaluminous (A/CNK = 0.84–0.94) and calc-alkaline signatures. Their mineralogical composition and remarkable low P2O5, Zr, Ce, and Nb concentrations confirm that they belong to I-type granites. They exhibit subduction-related magma geochemical characters such as enrichment in LILEs and LREEs and depletion in HFSEs and HREEs, with a low (La/Yb)N ratio (3.0–5.9) and apparent negative Nb anomaly. The positive Hf(t) values (+7.34 to +11.21) and young crustal model age (TDMC = 734–985 Ma) indicates a juvenile composition of the granodiorites. The data suggest that the Haweit granodiorites may have formed from partially melting a juvenile low-K mafic source. During subduction, the ascending asthenosphere melts might heat and partially melt the pre-existing lower crust mafic materials to generate the Haweit granodiorites in the middle segment of the Nubian Shield.
Candida auris is an emerging yeast pathogen that can cause invasive infections, particularly candidemia, in healthcare settings. Candida auris is characterized by resistance to multiple classes of ...antifungal drugs and high mortality.
To describe the risk factors, clinical characteristics, antifungal susceptibility pattern and outcomes of Candida auris blood stream infection.
We conducted a retrospective review of electronic medical records of C. auris fungemia cases in the facilities under Hamad Medical corporation, Qatar from 1/11/2018 to 31/7/2021. Demographic data, risk factors, antibiogram and 30-day outcome are described.
We identified 36 patients with C. auris fungemia. Most of the patients were in intensive care unit following severe COVID-19 pneumonia and had received steroids and broad-spectrum antibiotics. Most cases were central line related. Over 90% of isolates were non-susceptible to fluconazole, while amphotericin B resistance reached 85%. Factors associated with high mortality included initial SOFA score of 9 or above and absence of source control.
Our study reveals a concerning 41.6% mortality rate within 30 days of C. auris candidemia. Furthermore, the prevalence of amphotericin B resistance in Qatar exceeds what has been reported in the literature necessitating further exploration. Echinocandins retains nearly 100% susceptibility and should be prioritized as the treatment of choice. These findings emphasize the need for vigilant monitoring and appropriate management strategies to combat C. auris infections and improve patient outcomes.
Background
Aldehyde dehydrogenase 2 (ALDH2) protects against alcohol‐evoked cardiac dysfunction in male rodents, but its role in the estrogen (E2)‐dependent hypersensitivity of female rats to ...alcohol‐evoked myocardial oxidative stress and dysfunction is not known.
Methods
We addressed this question by studying the effect of cyanamide (ALDH2 inhibitor) on cardiac function, blood pressure, alcohol‐metabolizing enzyme (alcohol dehydrogenase, cytochrome P450 2E1, catalase, and ALDH2) activities, and cardiac redox status (reactive oxygen species, ROS; malondialdehyde, MDA) in the absence or presence of ethanol (EtOH) in female sham‐operated (SO) and ovariectomized (OVX) rats.
Results
Cyanamide attenuated the EtOH‐evoked myocardial dysfunction (reduced dP/dtmax and LVDP) in SO rats. EtOH, cyanamide, or their combination did not alter dP/dtmax or LVDP in OVX rats. Cyanamide induced cardiac oxidative stress and abrogated the subsequent alcohol‐evoked increases in ROS and MDA levels in SO rats. Neither EtOH nor cyanamide influenced ROS or MDA levels in OVX rats. Importantly, cyanamide exaggerated EtOH‐evoked hypotension in SO and uncovered this hypotensive response in OVX rats, which implicates ALDH2 in the vasodilating effect of EtOH.
Conclusions
Contrary to our hypothesis, cyanamide attenuated the E2‐dependent cardiac dysfunction caused by alcohol, likely by preconditioning the heart to oxidative stress, while exacerbating the vasodilating effect of alcohol. The latter might predispose to syncope when cyanamide and alcohol are combined in females.
Contrary to our hypothesis, cyanamide abrogated ethanol‐evoked myocardial dysfunction (reduced dP/dtmax) in female sham operated (SO) rats likely via induction of cardiac “preconditioning” (higher cardiac oxidative stress and malondialdehyde levels and ERK1/2 phosphorylation). Ethanol had no effect on cardiac function in ovariectomized (OVX) rats, which exhibited higher basal levels of these molecules due to the loss of estrogen. Consistent with clinical findings, cyanamide exaggerated ethanol‐evoked hypotension. More studies are warranted to understand the mechanism of this clinically relevant hypotensive effect.
This paper addresses the size-dependent free vibration of functionally graded viscoelastic (FGV) nanobeams including the simultaneous effects of the microstructure rotation and surface energy for the ...first time. Employing the Bernoulli–Euler beam theory, an internal damping mechanism based on Kelvin–Voigt model is adopted to simulate the viscoelastic behavior of the material. The modified couple stress theory and Gurtin–Murdoch surface elasticity theory are reconsidered and harnessed to capture the viscoelastic microstructure rotation and viscoelastic surface energy effects, respectively. The local-Cauchy stress, couple stress and surface stress tensors are obtained incorporating measures for the elastic and the viscous behaviors of the nanobeam. The elastic and viscous material properties of the bulk and surface of the FGV nanobeam are assumed to vary continuously in thickness direction according to a power law. A variational approach on the basis of D'Alembert's principle is employed to derive exactly the size-dependent governing differential equation and the associated nonclassical boundary conditions. An analytical expression is derived for the complex natural frequencies of a simply supported FGV nanobeam. In the context of linear viscoelasticity, the influences of different parameters such as the material damping, gradient index, material length-scale parameter, surface elasticity, surface residual stress, surface mass density, Poisson effect, thickness, and slenderness ratio on the free vibration of simply supported FGV nanobeams are comprehensively discussed. The results highlighted the profound effects of the small size, surface energy and viscoelastic behavior on the free vibration response of FGV nanobeams.
Ginger extract (GE) has sparked great interest due to its numerous biological benefits. However, it suffers from limited skin permeability, which challenges its transdermal application. The target of ...the current work was to develop transethosomes as a potential nanovehicle to achieve enhanced transdermal delivery of GE through the skin.
GE-loaded transethosomes were prepared by cold injection using different edge activators. The fabricated nanovesicles were evaluated for particle size, ζ-potential, encapsulation efficiency, and in vitro drug release. The selected formulation was then laden into the hydrogel system and evaluated for ex vivo permeability and in vivo anti-inflammatory activity in a carrageenan-induced rat-paw edema model.
The selected formulation comprised of sodium deoxycholate exhibited particle size of 188.3±7.66 nm, ζ-potential of -38.6±0.08 mV, and encapsulation efficiency of 91.0%±0.24%. The developed transethosomal hydrogel containing hydroxypropyl methylcellulose was homogeneous, pseudoplastic, and demonstrated sustained drug release. Furthermore, it exhibited improved flux (12.61±0.45 μg.cm
/second), apparent skin permeability (2.43±0.008×10
cm/second), and skin deposition compared to free GE hydrogel. In vivo testing and histopathological examination revealed that the GE transethosomal hydrogel exhibited significant inhibition of edema swelling compared to free GE hydrogel and ketoprofen gel. The animals that were treated with ginger transethosome hydrogel showed a significant decrement in reactive oxygen species and prostaglandin E
compared to untreated animals.
Transethosomes might be a promising new vehicle for GE for effective skin permeation and anti-inflammation. To the best of our knowledge, this work is the first utilization of transethosomes laden into hydrogel as a novel transdermal delivery system of GE.
Minimizing antibiotic resistance is a key motivation strategy in designing and developing new and combination therapy. In this study, a combination of the antibiotics (cefixime, levofloxacin and ...gentamicin) with Lysobacter enzymogenes (L. enzymogenes) bioactive proteases present in the cell- free supernatant (CFS) have been investigated against the Gram-positive methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA) and the Gram-negative Escherichia coli (E. coli O157:H7). Results indicated that L. enzymogenes CFS had maximum proteolytic activity after 11 days of incubation and higher growth inhibitory properties against MSSA and MRSA compared to E. coli (O157:H7). The combination of L. enzymogenes CFS with cefixime, gentamicin and levofloxacin at sub-MIC levels, has potentiated their bacterial inhibition capacity. Interestingly, combining cefixime with L. enzymogenes CFS restored its antibacterial activity against MRSA. The MTT assay revealed that L. enzymogenes CFS has no significant reduction in human normal skin fibroblast (CCD-1064SK) cell viability. In conclusion, L. enzymogenes bioactive proteases are natural potentiators for antimicrobials with different bacterial targets including cefixime, gentamicin and levofloxacin representing the beginning of a modern and efficient era in the battle against multidrug-resistant pathogens.
Herein, four endophytic fungal strains living in healthy roots of garlic were used to produce selenium nanoparticles (Se-NPs) via green synthesis. Penicillium verhagenii was found to be the most ...efficient Se-NPs producer with a ruby red color that showed maximum surface plasmon resonance at 270 nm. The as-formed Se-NPs were crystalline, spherical, and well-arranged without aggregation, and ranged from 25 to 75 nm in size with a zeta potential value of -32 mV, indicating high stability. Concentration-dependent biomedical activities of the P. verhagenii-based Se-NPs were observed, including promising antimicrobial activity against different pathogens (Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Candida albicans, C. glabrata, C. tropicalis, and C. parapsilosis) with minimum inhibitory concentration (MIC) of 12.5-100 µg mL
. The biosynthesized Se-NPs showed high antioxidant activity with DPPH-scavenging percentages of 86.8 ± 0.6% at a concentration of 1000 µg mL
and decreased to 19.3 ± 4.5% at 1.95 µg mL
. Interestingly, the Se-NPs also showed anticancer activity against PC3 and MCF7 cell lines with IC
of 225.7 ± 3.6 and 283.8 ± 7.5 µg mL
, respectively while it is remaining biocompatible with normal WI38 and Vero cell lines. Additionally, the green synthesized Se-NPs were effective against instar larvae of a medical insect, Aedes albopictus with maximum mortality of 85.1 ± 3.1, 67.2 ± 1.2, 62.10 ± 1.4, and 51.0 ± 1.0% at a concentration of 50 µg mL
for I, II, III, and IV-instar larva, respectively. These data highlight the efficacy of endophytic fungal strains for cost-effective and eco-friendly Se-NPs synthesis with different applications.
The tautomerizations mechanism of 4-(methylsulfanyl)-3(1Z)-1-(2-phenylhydrazinylidene) ethyl quinoline-2(1H)-one were inspected in the gas phase and ethanol using density function theory (DFT) M06-2X ...and B3LYP methods. Thermo-kinetic features of different conversion processes were estimated in temperature range 273-333 K using the Transition state theory (TST) accompanied with one dimensional Eckert tunneling correction (1D-Eck). Acidity and basicity were computed as well, and the computational results were compared against the experimental ones. Additionally, NMR, global descriptors, Fukui functions, NBO charges, and electrostatic potential (ESP) were discussed. From thermodynamics analysis, the keto form of 4-(methylsulfanyl)-3-(1Z)-1-(2 phenylhydrazinylidene) quinoline-2(1H)-one is the most stable form in the gas phase and ethanol and the barrier heights required for tautomerization process were found to be high in the gas phase and ethanol ~ 38.80 and 37.35 kcal/mol, respectively. DFT methods were used for UV-Vis electronic spectra simulation and the time-dependent density functional theory solvation model (TDDFT-SMD) in acetonitrile compounds.
Sex‐specific differences in mitochondrial function and free radical homeostasis are reported in the context of aging but not well‐established in pathogeneses occurring early in life. Here, we examine ...if sex disparity in mitochondria function, morphology, and redox status starts early and hence can be implicated in sexual dimorphism in cardiac as well as neurological disorders prevalent at young age. Although mitochondrial activity in the heart did not significantly vary between sexes, female brain exhibited enhanced respiration and higher reserve capacity. This was associated with lower H2O2 production in female cardiac and brain tissues. Using transmission electron microscopy, we found that the number of female cardiac mitochondria is moderately greater (117 ± 3%, P = 0.049, N = 4) than male's, which increased significantly for cortical mitochondria (134 ± 4%, P = 0.001, N = 4). However, male's cardiac mitochondria exhibited fragmented, circular, and smaller mitochondria relative to female's mitochondria, while no morphologic sex‐dependent differences were observed in cortical mitochondria. No sex differences were detected in Nox2 and Nox4 proteins or O2‐consuming/H2O2‐producing activities in brain homogenate or synaptosomes. However, a strong trend of increased EPR‐detected NOX superoxide in male synaptosomes hinted at higher superoxide dismutase activity in female brains, which was confirmed by two independent protocols. We also provide direct evidence that respiring mitochondria generally produce an order‐of‐magnitude lower reactive oxygen species (ROS) proportions than currently estimated. Our results indicate that sex differences in mitochondrial biogenesis, bioenergetics, and morphology may start at young age and that sex‐dependent SOD capacity may be responsible for differences in ROS homeostasis in heart and brain.
This study examines if sex disparity in mitochondrial function, morphology, and redox status starts early and hence can be implicated in sexual dimorphism in cardiac as well as neurological disorders prevalent at young age. Our results indicate that sex differences in mitochondrial biogenesis, bioenergetics, and morphology may start at young age and that sex‐dependent SOD capacity may be responsible for differences in reactive oxygen species (ROS) homeostasis in heart and brain.
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•Functionalization of magnetic-chitosan microparticles for chromate removal.•High efficiency and selectivity for imidazole carboxamide derivative.•Sorption capacities as high as ...6 mmol Cr g−1, at pH 2 (including Cr(VI) reduction).•Sips and pseudo-first order rate equations for isotherm and kinetic fitting, resp.•Highly efficient Cr desorption with 0.5 M HCl and sorbent recycling (5 cycles).
Textile and tannery industries are highly contaminating with discharge of high Cr concentrations. Developing bio-based sorbents with strong affinity for chromate, fast kinetics, and high recyclability is strategic for better reuse of industrial wastewater. Magnetic chitosan micro-particles (MC, for enhancing mass transfer) may constitute a solution for chromate removal from acidic solutions. The functionalization of this support with aminothiazole groups (ATA@MC) or imidazole carboxamide (AIC@MC) significantly improves chromate removal, with sorption capacities close to 6 mmol Cr g−1, at pH 2. The Langmuir and the Sips equations finely fit sorption isotherms, while the pseudo-first order rate equation fits well uptake kinetics (equilibrium within 60 min). Sorption and desorption properties are remarkably stable: sorption efficiency decreases by less than 6% at the fifth cycle (while the desorption efficiency maintains above 99%). The sorbents are highly selective for chromate removal from acidic tannery wastewater (against base metals). FTIR and XPS analyses are used for characterizing the materials and for identifying the binding mechanisms (including chromate reduction into Cr(III)). The sorbents are both showing promising performances for Cr(VI) removal in acidic solutions, including in very complex solutions such as tannery wastewater. AIC@MC is more selective for Cr(VI) removal, while ATA@MC has a broader reactivity for a wider family of metal ions. The antimicrobial properties of the functionalized sorbents are characterized by the determination of the zone of inhibition (ZOI) against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli and Candida albicans: the inhibition is slightly improved compared with magnetite chitosan microparticles. More generally, the Gram- bacteria are slightly more sensitive to the functionalized sorbents than Gram+ bacteria and Candida fungus.
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