Purpose: The activity of the cationic antimicrobial peptide WLBU2 was evaluated against planktonic cells and biofilms of multi-drug resistant (MDR) Acinetobacter baumannii and Klebsiella pneumoniae, alone and in combination with classical antimicrobial agents. Methods: Control American Type Culture Collection (ATCC) strains and MDR clinical isolates of A. baumannii and K. pneumoniae were utilized. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of WLBU2 alone and in combination with antimicrobials were determined by classical methods. The Calgary biofilm device was used to determine the minimum biofilm eradication concentration (MBEC). The MTT assay was used to determine the cytotoxicity of agents on eukaryotic cells. The electrophoretic mobility shift assay was used to evaluate the ability of WLBU2 to bind bacterial DNA. Results: The WLBU2 MIC and MBC values were identical indicating bactericidal activity. The MIC/MBC values ranged from 1.5625 to 12.5 μM. At these concentrations, Vero cells and human skin fibroblasts were viable. The MBEC of WLBU2 ranged from 25 to 200 μM. A significant loss of eukaryotic cell viability was observed at the MBEC range. The combination of sub-inhibitory concentrations of WLBU2 with amoxicillin-clavulanate or ciprofloxacin for K. pneumoniae, and with tobramycin or imipenem for A. baumannii, demonstrated synergism, leading to a significant decrease in MIC and MBEC values for some isolates and ATCC strains. However, all combinations were associated with considerable loss in eukaryotic cells’ viability. WLBU2 did not demonstrate the ability to bind bacterial plasmid DNA. Conclusion: WLBU2 in combination with antimicrobials holds promise in eradication of MDR pathogens.

The study investigated the prevalence of potentially pathogenic and drug resistant Escherichia coli among drinking water sources in Jordan. A total of 109 confirmed E. coli isolates were analyzed. Antimicrobial susceptibility testing was done using the Kirby Bauer disk diffusion method. Phenotypic identification of extended spectrum beta-lactamase (ESBL) and carbapenemase production was done using the double disk synergy test and the modified Hodge test, respectively. Isolates’ plasmid profiles were determined by gel electrophoresis. PCR was used for detection of virulence and resistance genes. Overall, 22.0% of the isolates were potentially intestinal pathogenic E. coli (IPEC); namely enteroaggregative E. coli (16.5%), enteropathogenic E. coli (2.8%), enteroinvasive E. coli (1.8%), and enterohemorrhagic E. coli (0.9%). A third of the isolates were multi-drug resistant. The highest rates of antimicrobials resistance were observed against ampicillin (93.6%) and sulfamethoxazole/trimethoprim (41.3%). All isolates were susceptible to imipenem, meropenem, doripenem and tigecycline. The prevalence of ESBL and carbapenemase producers was 54.1% and 2.8%, respectively. Bla_VIM was the most prevalent resistance gene (68.8%), followed by bla_CTX (50.5%), bla_TEM (45.9%), bla_NDM (11%), bla_KPC (4.6%), and bla_SHV (0.9%). Fifty-eight (53.2%) isolates contained one or more plasmid ranging from 1.0 to 8.0 kbp. Overall, high prevalence of potentially pathogenic and resistant isolates was observed.

This study aimed to identify phenotypic and genotypic aminoglycoside and quinolone non-susceptibility and the prevalence of aminoglycoside-modifying enzymes and plasmid-mediated quinolone resistance genes among K. pneumoniae clinical isolates from northern Jordan. K. pneumoniae isolates (n = 183) were tested for antimicrobial susceptibility using the Kirby-Bauer disk diffusion method. The double-disk synergy test was used for the detection of the extended-spectrum beta-lactamase phenotype. Polymerase chain reaction was used to detect genes encoding aminoglycoside-modifying enzyme (aac (3′)-II, aac (6′)-II, aac (6′)-Ib, ant (3″)-I, aph (3′)-VI, armA, and rmtB), and plasmid-mediated quinolone resistance (qnrA, qnrB, qnrC, qnrD, qnrS, acc(6′)-Ib–cr, qepA, and oqxAB) genes. Multi-locus sequence typing was used to elucidate the genetic diversity of selected isolates. The non-susceptibility percentages to aminoglycosides and quinolones were 65.0 % and 61.7 %, respectively. The most frequent aminoglycoside-modifying enzyme gene was ant (3″)-I at 73.8 %, followed by aac (6′)-Ib at 25.1 %, aac (3′)-II at 17.5 %, aph (3′)-VI at 12.0 %, armA at 9.8 %, and rmtB at 0.5 %. Aac (6′)-II was not detected among the isolates. The most frequent plasmid-mediated quinolone resistance gene was oqxAB at 31.7 %, followed by qnrS at 26.2 %, qnrB at 25.7 %, and aac(6′)-Ib–cr at 25.7 %. QnrA, qnrD, qebA, and qnrC were not detected among the isolates. Aac (3′)-II, aac (6′)-Ib, aph (3′)-VI, armA, qnrB, qnrS, and acc(6′)-Ib–cr were significantly associated with non-susceptibility to aminoglycosides, quinolones, and beta-lactams. Among 27 randomly selected K. pneumoniae isolates, the most common sequence type was ST2096, followed by ST348 and ST1207. Overall, 19 sequence types were observed, confirming a high level of genetic diversity among the isolates. High percentages of non-susceptibility to the studied antimicrobials were found and were associated with the presence of several resistance genes. Similar studies should be periodically carried out to monitor changes in the prevalence of resistance phenotypes and genotypes of isolates.

This study examined the prevalence of urovirulence genes in Uropathogenic Escherichia coli (UPEC) isolates obtained from Jordanian patients. In addition, antibiotic susceptibility profile of the isolates was also examined. Isolates (n=227) were subjected to PCR detection of vat, fyuA, chuA, yfcV, sivH, shiA, sisA, sisB and eco274 genes. The UPEC virulence genes prevalence rates were shiA (92%), sisA (72%), eco274 (44%), sivH (36%), vat (27%), yfcV (25%), sisB (25%), chuA (20%), and fyuA (18%). Approximately half and 82% of the isolates produced extended-spectrum beta-lactamases (ESBL) and were resistant to three or more antimicrobial classes, respectively. Among the isolates, highest resistance was for augmentin (83%) and nalidixic acid (78%). Modest resistance was for cefoxitin (21%) and cefixime (20%). Low resistance was for norfloxacin (5%), amikacin (3%), and ertapenem (0.4%). In conclusion, The UPEC virulence genes shiA and sisA are highly prevalent among the isolates. In addition, high resistance of UPEC to augmentin and nalidixic acid was reported. This may help in elucidating UPEC pathogenesis, and facilitate better treatment strategies for urinary tract infection patients.

The COVID-19 pandemic has caused a global public health emergency. Nutritional status is suggested to be related to the severity of COVID-19 infection. Herein, we aimed to explore the impact of using vitamin and mineral supplements prior to COVID-19 infection on disease severity and hospitalization. In addition, the prior use of aspirin as an anticoagulant on the disease severity was investigated. A cross-sectional, self-administered survey was conducted between March and July 2021. Recovered COVID-19 individuals (age ≥ 18 years, n = 2148) were recruited in the study. A multivariate logistic regression was used to evaluate the associations of supplements and aspirin use with COVID-19 disease severity and hospitalization status. Among the participants, 12.1% reported symptoms consistent with severe COVID-19, and 10.2% were hospitalized due to COVID-19. After adjustment for confounding variables (age, gender, BMI, cigarette smoking status, and the number of comorbidities), the multivariate logistic regression model showed that the consumption of vitamin D supplements prior to COVID-19 infection was associated with a significant decrease in disease severity (OR = 0.68, 95% CI 0.50 - 0.92; P = 0.01), and a lower risk of hospitalization (OR = 0.64, 95% CI 0.45 - 0.89; P = 0.01). On the other hand, there were no significant differences in the frequencies of severe illness and hospitalizations with the consumption of vitamin A, folic acid, vitamin B12, vitamin B complex, vitamin C, zinc, iron, selenium, calcium, magnesium, omega 3, and aspirin before COVID-19 infection. Among the investigated nutrients, the use of vitamin D prior to COVID-19 infection was associated with reduced disease severity and hospitalization. However, more studies are required to confirm this finding.