Reconfigurable Multi-beam On-Chip Patch Antenna Using Plasmonics Parasitic Graphene Strip Array

Plasmonics - This paper introduces on-chip patch antenna with electronic beam switching using graphene strip array for wireless communications at 415 GHz. The on-chip patch antenna is...     

Utilization of N,S-doped carbon dots as a fluorescent nanosensor for determination of cromolyn based on inner filter effect: application to aqueous humour

A simple and eco-friendly hydrothermal technique is used to prepare water soluble N- and S-co-doped carbon quantum dots probes (N,S-CQDs) from thiosemicarbazide and citric acid. Several characterization techniques were performed to ensure the successful synthesis of highly luminescent N,S-CQDs. The prepared probe exhibited analytical potential as an optical nanosensor for the spectrofluorimetric determination of cromolyn sodium (CRO) in its pharmaceutical dosage forms and aqueous humour. The emission intensity of the synthesized N,S-CQDs was measured at 411 nm after excitation at 345 nm. Addition of increasing concentrations of CRO to N,S-CQDs led to quenching of its fluorescence intensity. CRO was investigated within a wide concentration range 10.0–150.0 μM with a limit of detection of 2.0 μM and a limit of quantification of 6.0 μM. The quenching of fluorescent N,S-CQDs occurred through the inner filter effect (IFE). The developed spectrofluorimetric method was successfully optimized and validated according to the International Council of Harmonisation guidelines (ICH). The method greenness is proved through using both Eco-Scale and AGREE approaches.     

The rapid detection and differentiation of Mycobacterium tuberculosis complex members from cattle and water buffaloes in the delta area of Egypt,using a combination of real-time and conventional PCR

Molecular Biology Reports - Mycobacterium tuberculosis complex (MTBC) has the potential to cause infections in animals and human beings. The combination of real-time PCR targeting atpE or lpqT and...     

Prevalence,antimicrobial resistance profile,and characterization of multi-drug resistant bacteria from various infected wounds in North Egypt

Multi-drug resistant (MDR) bacteria associated with wounds are extremely escalating. This study aims to survey different wounds in Alexandria hospitals, North Egypt, to explore the prevalence and characteristics of MDR bacteria for future utilization in antibacterial wound dressing designs. Among various bacterial isolates, we determined 22 MDR bacteria could resist different classes of antibiotics. The collected samples exhibited the prevalence of mono-bacterial infections (60%), while 40% included poly-bacterial species due to previous antibiotic administration. Moreover, Gram-negative bacteria showed dominance with a ratio of 63.6%, while Gram-positive bacteria reported 36.4%. Subsequently, the five most virulent bacteria were identified following the molecular approach by 16S rRNA and physiological properties using the VITEK 2 automated system. They were deposited in GenBank as Staphylococcus haemolyticus MST1 ({"type":"entrez-nucleotide","attrs":{"text":"KY550377","term_id":"1304487819","term_text":"KY550377"}}KY550377), Pseudomonas aeruginosa MST2 ({"type":"entrez-nucleotide","attrs":{"text":"KY550378","term_id":"1304487820","term_text":"KY550378"}}KY550378), Klebsiella pneumoniae MST3 ({"type":"entrez-nucleotide","attrs":{"text":"KY550379","term_id":"1304487821","term_text":"KY550379"}}KY550379), Escherichia coli MST4 ({"type":"entrez-nucleotide","attrs":{"text":"KY550380","term_id":"1304487822","term_text":"KY550380"}}KY550380), and Escherichia coli MST5 ({"type":"entrez-nucleotide","attrs":{"text":"KY550381","term_id":"1304487823","term_text":"KY550381"}}KY550381). In terms of isolation source, S. haemolyticus MST1 was isolated from a traumatic wound, while P. aeruginosa MST2 and E. coli MST4 were procured from hernia surgical wounds, and K. pneumoniae MST3 and E. coli MST5 were obtained from diabetic foot ulcers. Antibiotic sensitivity tests exposed that K. pneumoniae MST3, E. coli MST4, and E. coli MST5 are extended-spectrum β-lactamases (ESBLs) bacteria. Moreover, S. haemolyticus MST1 belongs to the methicillin-resistant coagulase-negative staphylococcus (MRCoNS), whereas P. aeruginosa MST2 exhibited resistance to common empirical bactericidal antibiotics. Overall, the study provides new insights into the prevalent MDR bacteria in Egypt for further use as specific models in formulating antibacterial wound dressings.     

Synthesis and antimicrobial activity of meso-substituted polymethine cyanine dyes

The condensation reaction of equivalent amounts of 2-cyanomethyl benzooxazole or its derivatives with variously substituted aromatic aldehydes gave 2-cyano-styryl benzooxazole or its derivatives. The subsequent reaction of the 2-cyano-styryl benzooxazoles with 2(4)-methyl substituted heterocyclic quaternary salts afforded meso-substituted styryl-2(4)-polymethine cyanines. The condensation reaction of 2-cyanomethyl benzooxazole or its derivatives with alpha-nitroso-beta-naphthol followed by reaction with 2(4)-methyl substituted heterocyclic quaternary salts gave meso-substituted aza-2(4)-polymethine cyanines. The reaction of 2-cyanomethyl benzooxazole or its derivatives with N-methyl heterocyclic quaternary salts followed by the reaction with 2-methylquinolinium methiodide afforded the corresponding meso-substituted trimethine cyanine dyes. Elemental analyses, visible absorption, IR, (1)H NMR spectroscopy, and mass spectra established the structures of these compounds. The relationship between the structure and properties of these dyes has been studied and the solvatochromic behavior of some selected cyanine dyes in organic solvents is discussed. Finally, the antimicrobial activity of selected novel dyes was investigated in vitro using a wide spectrum of microbial strains.     

Thioxanthene-derived analogs as sigma(1) receptor ligands

An investigation of the structure-affinity relationships for the binding of thioxanthene-related structures indicates that an intact thioxanthene ring is not required for binding at sigma(1) receptors, and that with the appropriate structural modifications, affinity can be enhanced to the subnanomolar level. Certain of the analogs displayed sigma(1)-fold selectivity for sigma(1) versus sigma(2) receptors.     

Nitric oxide and oxidative stress in brain and heart of normal rats treated with doxorubicin: role of aminoguanidine

Doxorubicin (DOX) is a potent antitumor antibiotic drug known to cause severe cardiac toxicity. Moreover, its adverse effects were found to be extended to the cerebral tissue. Several mechanisms for this toxicity have been ascribed. Currently, one of the most accepted mechanisms is through free radicals; however, the exact role of nitric oxide (NO) is still unclear. Accordingly, a NO-synthase inhibitor with some antioxidant property, aminoguanidine (AG), was selected to examine its potential protective effect against DOX-induced toxicity. Male Wistar albino rats (150-200 g) were allocated into a normal control group, DOX-induced toxicity group, and DOX + AG-treated group. DOX was injected i.p. at a dose of 10 mg/kg divided into four equal injections over a period of 2 weeks. AG was injected i.p. at a dose of 100 mg/kg 1 h before each DOX injection. The animals were sacrificed 24 h after the last DOX injection and the following parameters were measured: serum lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) activities, cardiac and cerebral contents of malondialdehyde (MDA), conjugated diene (CD), glutathione (GSH), NO, and cytosolic calcium, as well as superoxide dismutase (SOD) and glutathione peroxidase (GSHP(X)) activities. Cardiotoxicity was manifested by a marked increase in serum LDH and CPK in addition to the sharp increase in MDA reaching eightfolds the basal level. This was accompanied by significant increase in CD, NO, cytosolic calcium, SOD, and GSHP(X) content/activity by 69, 85, 76, 125, and 41% respectively as compared to normal control. On the other hand, GSH was significantly depressed. In brain, only significant increase in MDA and GSHP(X) and decrease in GSH were obtained but to a lesser extent than the cardiac tissue. AG treatment failed to prevent the excessive release of cardiac enzymes; however, it alleviated the adverse effects of DOX in heart. AG administration resulted in marked decrease in the elevated levels of MDA, NO, SOD, and GSHP(X), however, MDA level was still pathological. The altered parameters in brain were restored by AG. It is concluded that, AG could not provide complete protection against DOX-induced toxicity. Therefore, it is recommended that, maintenance of the endogenous antioxidant, GSH, and regulation of calcium homeostasis must be considered, rather than NO formation, to guard against DOX-induced toxicity.