Search Results (12)

Background and Objectives: Urinary tract infections [UTIs] are considered the third most known risk of infection in human health around the world. There is increasing appreciation for the pathogenicity of Gram-positive and Gram-negative strains in UTIs, aside from fungal infection, as they have numerous virulence factors. Materials and Methods: In this study, fifty urine samples were collected from patients suffering from UTI. Among the isolates of UTI microbes, six isolates were described as MDR isolates after an antibiotic susceptibility test carried out using ten different antibiotics. An alternative treatment for microbial elimination involved the use of biosynthesized silver nanoparticles (AgNPs) derived from Solanum lycopersicum [S. cumin]. Results: The sizes and shapes of AgNPs were characterized through TEM imaging, which showed spherical particles in a size range of 35–80 nm, of which the average size was 53 nm. Additionally, the silver nanoparticles (AgNPs) demonstrated inhibitory activity against Staphylococcus aureus (OR648079), exhibiting a 31 mm zone of inhibition at a minimum inhibitory concentration (MIC) of 4 mg/mL and a minimum bactericidal concentration (MBC) of 8 mg/mL. This was followed by Aspergillus niger (OR648075), which showed a 30 mm inhibition zone at an MIC of 16 mg/mL and a minimum fungicidal concentration (MFC) of 32 mg/mL. Then, Enterococcus faecalis (OR648078), Klebsiella pneumoniae (OR648081), and Acinetobacter baumannii (OR648080) each displayed a 29 mm zone of inhibition at an MIC of 8 mg/mL and an MBC of 16 mg/mL. The least inhibition was observed against Candida auris (OR648076), with a 25 mm inhibition zone at an MIC of 16 mg/mL and an MFC of 32 mg/mL. Furthermore, AgNPs at different concentrations removed DPPH and H₂O₂ at an IC50 value of 13.54 μg/mL. Also, AgNPs at 3 mg/mL showed remarkable DNA fragmentation in all bacterial strains except Enterococcus faecalis. The phytochemical analysis showed the presence of different active organic components in the plant extract, which concluded that rutin was 88.3 mg/g, garlic acid was 70.4 mg/g, and tannic acid was 23.7 mg/g. Finally, AgNPs concentrations in the range of 3–6 mg/mL showed decreased expression of two of the fundamental genes necessary for biofilm formation within Staphylococcus aureus, fnbA (6 folds), and Cna (12.5 folds) when compared with the RecA gene, which decreased by one-fold when compared with the control sample. These two genes were submitted with NCBI accession numbers [OR682119] and [OR682118], respectively. Conclusions: The findings from this study indicate that biosynthesized AgNPs from Solanum lycopersicum exhibit promising antimicrobial and antioxidant properties against UTI pathogens, including strains resistant to multiple antibiotics. This suggests their potential as an effective alternative treatment for UTIs. Further research is warranted to fully understand the mechanisms of action and to explore the therapeutic applications of these nanoparticles in combating UTIs. Full article

Enterococci are troublesome nosocomial, opportunistic Gram-positive cocci bacteria showing enhanced resistance to many commonly used antibiotics. This study aims to investigate the prevalence and genetic basis of antibiotic resistance to macrolides, lincosamides, and streptogramins (MLS) in Enterococci, as well as the correlation between MLS resistance and biocide resistance. From 913 clinical isolates collected from King Khalid Hospital, Hail, Saudi Arabia, 131 isolates were identified as Enterococci spp. The susceptibility of the clinical enterococcal isolates to several MLS antibiotics was determined, and the resistance phenotype was detected by the triple disk method. The MLS-involved resistance genes were screened in the resistant isolates. The current results showed high resistance rates to MLS antibiotics, and the constitutive resistance to all MLS (cMLS) was the most prevalent phenotype, observed in 76.8% of resistant isolates. By screening the MLS resistance-encoding genes in the resistant isolates, the erythromycin ribosome methylase (erm) genes that are responsible for methylation of bacterial 23S rRNA were the most detected genes, in particular, ermB. The ereA esterase-encoding gene was the most detected MLS modifying-encoding genes, more than lnuA (adenylation) and mphC (phosphorylation). The minimum inhibitory concentrations (MICs) of commonly used biocides were detected in resistant isolates and correlated with the MICs of MLS antibiotics. The present findings showed a significant correlation between MLS resistance and reduced susceptibility to biocides. In compliance with the high incidence of the efflux-encoding genes, especially mefA and mefE genes in the tolerant isolates with higher MICs to both MLS antibiotics and biocides, the efflux of resistant isolates was quantified, and there was a significant increase in the efflux of resistant isolates with higher MICs as compared to those with lower MICs. This could explain the crucial role of efflux in developing cross-resistance to both MLS antibiotics and biocides. Full article

Wild migratory birds have the capability to spread avian influenza virus (AIV) over long distances as well as transmit the virus to domestic birds. In this study, swab and tissue samples were obtained from 190 migratory birds during close surveillance in Egypt in response to the recent outbreaks of the highly pathogenic avian influenza (HPAI) H5N1 virus. The collected samples were tested for a variety of AIV subtypes (H5N1, H9N2, H5N8, and H6N2) as well as other pathogens such as NDV, IBV, ILT, IBDV, and WNV. Among all of the tested samples, the HPAI H5N1 virus was found in six samples; the other samples were found to be negative for all of the tested pathogens. The Egyptian HPAI H5N1 strains shared genetic traits with the HPAI H5N1 strains that are currently being reported in Europe, North America, Asia, and Africa in 2021–2022. Whole genome sequencing revealed markers associated with mammalian adaption and virulence traits among different gene segments, similar to those found in HPAI H5N1 strains detected in Europe and Africa. The detection of the HPAI H5N1 strain of clade 2.3.4.4b in wild birds in Egypt underlines the risk of the introduction of this strain into the local poultry population. Hence, there is reason to be vigilant and continue epidemiological and molecular monitoring of the AIV in close proximity to the domestic–wild bird interface. Full article

Non-muscle Invasive Bladder Cancer (NMIBC) accounts for 80% of all bladder cancers. Although it is mostly low-grade tumors, its high recurrence rate necessitates three-times-monthly follow-ups and cystoscopy examinations to detect and prevent its progression. A rapid liquid biopsy-based assay is needed to improve detection and reduce complications from invasive cystoscopy. Here, we present a rapid spectroscopic method to detect the recurrence of NMIBC in urine. Urine samples from previously-diagnosed NMIBC patients (n = 62) were collected during their follow-up visits before cystoscopy examination. Cystoscopy results were recorded (41 cancer-free and 21 recurrence) and attenuated total refraction Fourier transform infrared (ATR-FTIR) spectra were acquired from urine samples using direct application. Spectral processing and normalization were optimized using parameter grid searching. We assessed their technical variability through multivariate analysis and principal component analysis (PCA). We assessed 35 machine learning models on a training set (70%), and the performance was evaluated on a held-out test set (30%). A Regularized Random Forests (RRF) model achieved a 0.92 area under the receiver operating characteristic (AUROC) with 86% sensitivity and 77% specificity. In conclusion, our spectroscopic liquid biopsy approach provides a promising technique for the early identification of NMIBC with a less invasive examination. Full article

Gold nanoparticles have gained popularity as an effective drug delivery vehicle due to their unique features. In fact, antibiotics transported via gold nanoparticles have significantly enhanced their potency in the recent past. The present study used an approach to synthesize gold nanoparticles in one step with the help of cefoxitin antibiotic as a reducing and stabilizing agent. Cefoxitin is a second-generation cephalosporin that loses its potential due to modification in the porins (ompK35 and ompK36) of Gram-negative pathogens. Thus, the present study has developed an idea to revive the potential of cefoxitin against clinical Gram-negative pathogens, i.e., Escherichia coli and Klebsiella pneumoniae, via applying gold nanoparticles as a delivery tool. Prior to antibacterial activity, characterization of cefoxitin–gold nanoparticles was performed via UV–visible spectrophotometry, dynamic light scattering, and electron microscopy. A characteristic UV–visible scan peak for gold nanoparticles was observed at 518 nm, ζ potential was estimated as −23.6 ± 1.6, and TEM estimated the size in the range of 2–12 nm. Moreover, cefoxitin loading efficiency on gold nanoparticles was calculated to be 71.92%. The antibacterial assay revealed that cefoxitin, after loading onto the gold nanoparticles, become potent against cefoxitin-resistant E. coli and K. pneumoniae, and their MIC₅₀ values were estimated as 1.5 μg/mL and 2.5 μg/mL, respectively. Here, gold nanoparticles effectively deliver cefoxitin to the resistant pathogens, and convert it from unresponsive to a potent antibiotic. However, to obtain some convincing conclusions on the human relevance, their fate and toxicity need to be evaluated. Full article

The highly pathogenic avian influenza (HPAI) H5N8 virus was first detected in Egypt in late 2016. Since then, the virus has spread rapidly among different poultry sectors, becoming the dominant HPAI H5 subtype reported in Egypt. Different genotypes of the HPAI H5N8 virus were reported in Egypt; however, the geographic patterns and molecular evolution of the Egyptian HPAI H5N8 viruses are still unclear. Here, extensive epidemiological surveillance was conducted, including more than half a million samples collected from different poultry sectors (farms/backyards/live bird markets) from all governorates in Egypt during 2019–2021. In addition, genetic characterization and evolutionary analyses were performed using 47 selected positive H5N8 isolates obtained during the same period. The result of the conducted surveillance showed that HPAI H5N8 viruses of clade 2.3.4.4b continue to circulate in different locations in Egypt, with an obvious seasonal pattern, and no further detection of the HPAI H5N1 virus of clade 2.2.1.2 was observed in the poultry population during 2019–2021. In addition, phylogenetic and Bayesian analyses revealed that two major genotypes (G5 and G6) of HPAI H5N8 viruses were continually expanding among the poultry sectors in Egypt. Notably, molecular dating analysis suggested that the Egyptian HPAI H5N8 virus is the potential ancestral viruses of the European H5N8 viruses of 2020–2021. In summary, the data of this study highlight the current epidemiology, diversity, and evolution of HPAI H5N8 viruses in Egypt and call for continuous monitoring of the genetic features of the avian influenza viruses in Egypt. Full article

Nowadays, endophytic fungi represent a rich source of biological active compounds. In the current study, twelve endophytic fungal species were isolated from Avicennia marina leaves. From the isolates, Aspergillus niger, Penicillium rubens and Alternaria alternata recorded the highest isolation frequency (80%), relative density (12.5%) and antimicrobial activity. The antimicrobial and anticancer activities of P. rubens were more effective than those of A. niger and A. alternata; therefore, its identification was confirmed via the ITS rRNA gene. Filtrate extracts of P. rubens, A. alternata and A. niger were analyzed using GC-MS and showed different detected constituents, such as acetic acid ethyl ester, N-(4,6-Dimethyl-2-pyrimidinyl)-4-(4-nitrobenzylideneamino) benzenesulfonamide, 1,2-benzenedicarboxylic acid, hexadecanoic acid and octadecanoic acid. Filtrate extract of P. rubens exhibited the presence of more compounds than A. alternata and A. niger. Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and Aspergillus fumigatus were more inhibited by P. rubens extract than A. alternata or A. niger, with inhibition zones of 27.2 mm, 22.21 mm, 26.26 mm, 27.33 mm, 28.25 mm and 8.5 mm, respectively. We observed negligible cytotoxicity of P. rubens extract against normal cells of human lung fibroblasts (WI-38 cell line), unlike A. alternata and A. niger extracts. Proliferation of prostate cancer (PC-3) was inhibited using P. rubens extract, exhibiting mortality levels of 75.91% and 76.2% at 200 µg/mL and 400 µg/mL of the extract. Molecular docking studies against the crystal structures of C. albicans (6TZ6) and the cryo-EM structure of B. subtilis (7CKQ) showed significant interactions with benzenedicarboxylic acid and N-(4,6-dimethyl-2-pyrimidinyl)-4-(4-nitrobenzylideneamino) benzenesulfonamide as a constituent of P. rubens extract. N-(4,6-dimethyl-2-pyrimidinyl)-4-(4-nitrobenzylideneamino) benzenesulfonamide had the highest scores of −6.04905 kcal/mol and −6.590 kcal/mol towards (6tz6) and (7CKQ), respectively. Full article

Over the last few years, the number of grid-connected photovoltaic systems (GCPVS) has expanded substantially. The increase in GCPVS integration may lead to operational issues for the grid. Thus, modern GCPVS control mechanisms should be used to improve grid efficiency, reliability, and stability. In terms of frequency stability, conventional generating units usually have a governor control that regulates the primary load frequency in cases of imbalance situations. This control should be activated immediately to avoid a significant frequency variation. Recently, renewable distribution generators such as PV power plants (PVPPs) are steadily replacing conventional generators. However, these generators do not contribute to system inertia or frequency stability. This paper proposes a control strategy for a GCPVS with active power control (APC) to support the grid and frequency stability. The APC enables the PVPP to withstand grid disturbances and maintain frequency within a normal range. As a result, PVPP is forced to behave similar to traditional power plants to achieve frequency steadiness stability. Frequency stability can be achieved by reducing the active power output fed into the grid as the frequency increases. Additionally, to maintain power balance on both sides of the inverter, the PV system will produce the maximum amount of active power achievable based on the frequency deviation and the grid inverter’s rating by working in two modes: normal and APC (disturbance). In this study, a large-scale PVPP linked to the utility grid at the MV level was modeled in MATLAB/Simulink with a nominal rated peak output of 2000 kW. Analyses of the suggested PVPP’s dynamic response under various frequency disturbances were performed. In this context, the developed control reduced active power by 4%, 24%, and 44% when the frequency climbed to 50.3 Hz, 50.8 Hz, and 51.3 Hz, respectively, and so stabilized the frequency in the normal range, according to grid-code requirements. However, if the frequency exceeds 51.5 Hz or falls below 47.5 Hz, the PVPP disconnects from the grid for safety reasons. Additionally, the APC forced the PVPP to feed the grid with its full capacity generated (2000 kW) at normal frequency. In sum, the large-scale PVPP is connected to the electrical grid provided with APC capability has been built. The system’s capability to safely ride through frequency deviations during grid disturbances and resume initial conditions was achieved and improved. The simulation results show that the given APC is effective, dependable, and suitable for deployment in GCPVS. Full article

Molybdenum ions (Mo) can improve plants’ nutritional value primarily by enhancing nitrogenous metabolism. In this study, the comparative effects of seed priming using Mo were evaluated among sproutings of Canavalia species/cultivars, including Canavalia ensiformis var. gladiata (CA1), Canavalia ensiformis var. truncata Ricker (CA2), and Canavalia gladiata var. alba Hisauc (CA3). Mo impacts on growth, metabolism (e.g., nitrogen and phenolic metabolism, pigment and total nutrient profiles), and biological activities were assayed. Principal component analysis (PCA) was used to correlate Mo-mediated impacts. The results showed that Mo induced photosynthetic pigments that resulted in an improvement in growth and increased biomass. The N content was increased 0.3-fold in CA3 and 0.2-fold in CA1 and CA2. Enhanced nitrogen metabolism by Mo provided the precursors for amino acids, protein, and lipid biosynthesis. At the secondary metabolic level, phenolic metabolism-related precursors and enzyme activities were also differentially increased in Canavalia species/cultivars. The observed increase in metabolism resulted in the enhancement of the antioxidant (2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical scavenging, 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP)) and antidiabetic potential (Glycemic index (GI) and inhibition activity of α-amylase, and α-glucosidase) of species. The antioxidant activity increased 20% in CA3, 14% in CA1, and 8% in CA2. Furthermore, PCA showed significant variations not only between Mo-treated and untreated samples but also among Canavalia species. Overall, this study indicated that the sprouts of Canavalia species have tremendous potential for commercial usage due to their high nutritive value, which can be enhanced further with Mo treatment to accomplish the demand for nutritious feed. Full article

Highly pathogenic avian influenza (HPAI) viruses continue to circulate worldwide, causing numerous outbreaks among bird species and severe public health concerns. H5N1 and H5N8 are the two most fundamental HPAI subtypes detected in birds in the last two decades. The two viruses may compete with each other while sharing the same host population and, thus, suppress the spread of one of the viruses. In this study, we performed a statistical analysis to investigate the temporal correlation of the HPAI H5N1 and HPAI H5N8 subtypes using globally reported data in 2015–2020. This was joined with an in-depth analysis using data generated via our national surveillance program in Egypt. A total of 6412 outbreaks were reported worldwide during this period, with 39% (2529) as H5N1 and 61% (3883) as H5N8. In Egypt, 65% of positive cases were found in backyards, while only 12% were found in farms and 23% in live bird markets. Overall, our findings depict a trade-off between the number of positive H5N1 and H5N8 samples around early 2017, which is suggestive of the potential replacement between the two subtypes. Further research is still required to elucidate the underpinning mechanisms of this competitive dynamic. This, in turn, will implicate the design of effective strategies for disease control. Full article

Bovine leukemia virus (BLV) is distributed worldwide and affects dairy cattle causing severe economic losses. The BLV has been serologically reported in Egypt, but few studies have evaluated its associated risk factors and genetic classification. Therefore, this study assessed risk factors associated with BLV infection and identified the genetic diversity of the Egyptian strain. The study was conducted on 500 dairy cattle distributed in four Governorates located in Northern Egypt. Overall, the seroprevalence of BLV infection among Egyptian dairy cattle was 18.2%. The grazing cattle in the losing house system had higher odds for BLV seropositivity, and bad practice such as the use of a single needle or one plastic glove for more than one animal was considered a significant risk factor for BLV infection. Besides, the sequencing and phylogenetic analysis for one Egyptian BLV strain was performed, and the obtained results confirmed the clustering of Egyptian BLV strain into genotype-1. The assessment of associated risk factors for BLV infection and determination of its genetic classification are essential to implement an effective control program. Full article

Highly pathogenic avian influenza (HPAI) H5N1 and H5N8 have become endemic among domestic poultry in Egypt since 2006 and 2016, respectively. In parallel, the low pathogenic avian influenza H9N2 virus has been endemic since 2010. Despite the continuous circulation of these subtypes for several years, no natural reassortant has been detected so far among the domestic poultry population in Egypt. In this study, the HPAI (H5N2) virus was isolated from a commercial duck farm, giving evidence of the emergence of the first natural reassortment event in domestic poultry in Egypt. The virus was derived as a result of genetic reassortment between avian influenza viruses of H5N8 and H9N2 subtypes circulating in Egypt. The exchange of the neuraminidase segment and high number of acquired mutations might be associated with an alteration in the biological propensities of this virus. Full article