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Quorum sensing (QS) is a bacterial cell-to-cell communication mechanism that plays an essential role in bacterial pathogenesis. QS governs bacterial behavior and controls biofilm formation, which in turn contributes to antibiotic resistance. Therefore, identifying and synthesizing novel compounds to overcome QS and inhibit biofilm formation are essential. Coumarins are important plant-derived natural products with wide-ranging bioactivities and extensive applications, including antibacterial, antifungal, anticoagulant, antioxidant, anticancer, and anti-inflammatory properties. Additionally, coumarins are capable of QS rewiring and biofilm formation inhibition, leading to higher susceptibility to antimicrobial agents and less antibiotic resistance. Therefore, in this review, we aim to provide an overview of QS and biofilm formation. This review also discusses the role of natural and synthesized coumarins in controlling QS, inhibiting biofilm formation, and inducing synergy in antibiotic–coumarin combinations. Hence, this review emphasizes the potential of coumarin compounds to act as antibacterial agents and demonstrates their ability to alleviate antibiotic resistance. [ABSTRACT FROM AUTHOR]

Date syrup is a very rich nutritional and medicinal product. It can be used alone or mixed with other food products. Now, it is widely used as a natural sweetener instead of harmful sugar in several food products. However, date syrup contains higher levels of 5-hydroxyl methyl furfural (5-HMF) (heat-induced toxicant). HMF is normally formed during processing via Maillard reaction as a result of heating. Thus, the present study aims at investigating the effect of gamma irradiation in reducing HMF content and improving the quality properties of date syrup. Date syrup samples (commercial) were irradiated at different doses (15, 20 and 25 kGy). HMF content was determined using the HPLC method. The obtained results showed that γ-irradiation reduced the toxic compound (HMF) in date syrup, where irradiation dose (20 kGy) recorded the lowest HMF level (1956.40 mg/kg) with a reduction percentage of 46.96% compared to the non-irradiated sample. While the non-irradiated sample revealed the highest level of HMF and bacterial growth. Therefore, γ-irradiation is considered an effective treatment that reduces HMF using a particular dose (20 kGy) and prevents microbial growth (20–25 KGy). Furthermore, it may increase the nutritional value by increasing minerals' bioavailability (15 kGy). [ABSTRACT FROM AUTHOR]

The newly synthesized 1,2,3-triazole-thiazole hybrids were first evaluated for their antimicrobial activity against different microbial strains. Most of it showed a marked selectivity against Gram-positive and Gram-negative bacterial strains. The MIC assay was then assessed; for S. aureus, 4a was equipotent to the reference neomycin, while 3a, 3b, and 8b were 2-fold lower. For E. coli, compounds 3a, 4a, and 8c were equipotent to neomycin, while 5a was 8-fold higher, and 8d was 2-fold higher. Most of tested compounds showed superiority to the reference drug against C. albicans; 8a and 8e showed MIC value of 16-fold higher than neomycin, while 3a was 8-fold higher. Also, 3b and 8f were 4-fold higher; 8d was 2-fold higher, while 5a was equipotent to neomycin against the same microbe. Further biofilm formation inhibition assay was conducted to the most active compounds, 5a was the most active against the three types of bacterial strains. [ABSTRACT FROM AUTHOR]

Abstract Background Cervicofacial vascular lesions are one of the most challenging diseases managed by intervention radiologists and specialized surgeons. These lesions were diagnosed to be vascular in origin by other imaging techniques such as Duplex and/or magnetic resonance imaging (MRI). All patients underwent computed tomographic angiography (CTA) to confirm the diagnosis as well as to decide the most effective choice of management based on multidisciplinary team (MDT). Then, Digital subtraction angiography (DSA) was done as it is offering an accurate vascular map for the vascular lesions which is inevitable for successful super-selective endovascular embolization which can be done at same sitting. Small cases of arteriovenous malformations (AVMs) were sufficiently managed by only embolization, whereas cases of adequately embolized large AVMs as well as juvenile nasopharyngeal angiofibroma (JNA) cases were followed by surgery with the advantage of less blood loss and decreasing operation time as well as complications. This prospective study was done to highlight the role of combined CTA and DSA in cervicofacial vascular lesion management. Results Twenty patients were included in our study: 16 patients were males, and 4 were females; 17 of them were under 40 years, and three were above 40 years. Preoperative embolization was done in 12 patients, which were all the cases of JNAs and large AVMs. Four patients were managed by only embolization as a definitive treatment. Complete technical success rate was about 94%, while only 6% (single case) of the partial technical success rate which was due to a very small accessory feeder that could not be catheterized even with repeated trials. Conclusions Combined CTA and DSA is the cornerstone for managing vascular lesions in the cervicofacial region, which necessitates a MDT to decide the most beneficial and least complicated way for management.

AbstractA new series of 1,3,4-thiadiazole linked to sulfa-azo derivatives via hydrazono-methyl bridge were synthesized via the reaction of methyl ((E)-(sulfa-derivatives)diazenyl) benzylidene)hydrazine-1-carbodithioates 1a-e with ethyl ester and acetyl hydrazonyl halides 2a-d. The chemical structures of the newly 1,3,4-thiadiazoles 3a-t have been clarified considring their elemental and spectral analysis. Antimicrobial activity of the newly 1,3,4-thiadiazoles was determined for Staphylococcus aureus, Escherichia coli, Candida albicans, as well as Aspergillus niger using the cup agar plate diffusion method. Out of the twenty compounds, compounds 3j, 3k, 3l, and 3s with isoxazole sulfonamides were selected for MIC assay. Compound 3j was equipotent with neomycin control drug against all tested strains, while compound 3k was 4-fold higher than neomycin against S. aureus, E. coli, and C. albicans with MIC values of 9.77, 19.53, and 19.53 μg/mL, respectively. Compound 3l was equipotent with neomycin against S. aureus and C. albicans, while it was 2-fold higher than neomycin against E. coli with MIC of 39.06 μg/mL. For 3s, it was less potent than neomycin against all tested microbs with 2-fold and 4-fold less potent. Further scanning electron microscopy (SEM) investigation has been studied to reveal the disruption effect of the selected potent antimicrobial compound (3k) on the intact cells of tested microbs S. aureus, E. coli in addition to C. albicans. Results showed that 3k exhibited a noticeable effect on destroying microbial cell walls. Furthermore, molecular docking study has been done to assess the binding behavior of two most effective compounds 3k and 3l with the target crystal structure of dihydropteroate synthase (PDB: 6CLV for S. aureus) and (PDB: 5U14 for E. coli). Compound 3k was shown to be able to form stable complexes with both target enzymes of dihydropteroate synthase through hydrogen bonding and hydrophobic interactions. [ABSTRACT FROM AUTHOR]

The present study contributes to overcoming the serious drawback of the traditional stirred slurry catalytic reactor, namely, the costly and time‐consuming separation of the catalyst particles from the final product using a stationary fixed bed of Raschig rings placed above a rotating impeller. The rate of diffusion‐controlled reactions was measured in terms of the mass transfer coefficient under different conditions of impeller rotation speed, Raschig ring diameter, and bed height. The rate of mass transfer was determined by a technique which involves measuring the rate of diffusion‐controlled dissolution of copper in acidified dichromate. The data were correlated by a dimensionless correlation which can be used to scale up and design the reactor. The reactor performance was measured in terms of the mass transfer coefficient and the energy utilization efficiency. Possible applications of the reactor in conducting diffusion‐controlled reactions were highlighted. [ABSTRACT FROM AUTHOR]

The Neoproterozoic basement rocks in Ar Rayn terrane set as parts in the Eastern Arabian Shield. It focus the petrological and kinematic vorticity for high deformed volcanic and granitoids rocks in the Al-Amar locality. The volcanic rocks divide into two main series, the eastern sequence cycle represents dacite, rhyodacite, rhyolite and ignimbrites, and the western sequence cycle characterizes andesite and pyroclastics. Furthermore, the granitoids rocks content monzodiorite, tonalite, granodiorite and alkali-feldspar granite. For assessing the proportions of pure and simple shear contributions in penetrative deformed rocks, the kinematic vorticity number (Wm) to the mean appreciation by applying porphyroclast, rotating in a flowing matrix is crucial. In the Ar Rayn terrane of Arabian shield, kinematic vorticity numbers for high deformed metavolcanics and granitoids gneisses vary from 0.4 to 0.6. The deformation in the studied area varied from simple shear, according to vorticity and strain studies. Nappe stacking getting ready during the thrusting activity only through the Al Amar –Idsas fault, according to the results, most likely due to brittle imbrication. A penetrative sub-horizontal foliation formed sub-parallel to the nappe contacts with the beneath laying nappes, showing that the ductile strain was superimposed on the construction of the nappe under high pressure. The Ar Rayn terrane was created sub-horizontal foliation by the buildup of ductile strain during under plating, which was induced by a vertical shortening component. This foliation was formed in the majority of cases during the thrusting nappes upon each other, implying that nappe stacking was related to vertical shortening due to a massive scale by the active Al Amar –Ideas fault.