Aorto-Uni-Iliac Stent Grafts with and without Crossover Femorofemoral Bypass for Treatment of Abdominal Aortic Aneurysms: A Parallel Observational Comparative Study

We investigated the safety and efficacy of primary aorto-uni-iliac (AUI) endovascular aortic repair (EVAR) without fem-fem crossover in patients with abdominal aortic aneurysm (AAA) and concomitant aortoiliac occlusive disease. 537 EVARs were implemented between 2002 and 2015 in University Hospital Galway, a tertiary referral center for aortic surgery and EVAR. We executed a parallel observational comparative study between 34 patients with AUI with femorofemoral crossover (group A) and six patients treated with AUI but without the crossover (group B). Group B patients presented with infrarenal AAAs with associated total occlusion of one iliac axis and high comorbidities. Technical success was 97% (n=33) in group A and 85% (n=5) in group B (P=0.31). Primary and assisted clinical success at 24 months were 88% (n=30) and 12% (n=4), respectively, in group A, and 85% (n=5) and 15% (n=1), respectively, in group B (P=0.125). Reintervention rate was 10% (n=3) in group A and 0% in group B (P=0.084). No incidence of postoperative critical lower limb ischemia or amputations occurred in the follow-up period. AUI without crossover bypass is a viable option in selected cases

Humoral and cellular immune responses to modified hepatitis B plasmid DNA vaccine in mice

Purpose: To evaluate the immunogenicity and types of immune response of a quality-controlled modified recombinant hepatitis B surface antigen (HBsAg) plasmid encoding HBsAg in mice.Methods: The characterized plasmid DNA was used in the immunization of Balb/c mice. Three groups of mice were intramuscularly injected with three different concentrations (50, 25 and 10 μg/100 μL) of the modified plasmid. Humoral immune response was monitored by enzyme-linked immunosorbent assay (ELISA), while cellular immune response was investigated by analysis of spleen cytokine profile (TNFα, IFN γ and IL2) as well as CD69 expression level in CD4 and CD8 positive cells.Results: In general, the activated CD4 cells showing intracellular cytokines were higher than CD8 positive population of cells (p < 0.05). These findings indicate that the vaccine induced both a humoral and cellular immunity. Cytokine profile also showed high levels of TNFα, IFN γ and IL2 and CD69 expression in the group of animals immunized at a dose of 10 μg when compared to control group (p < 0.05).Conclusion: A 10 μg dose intramuscular injection of the modified DNA-based vaccine encoding HBsAg in mice induces both high humoral and cellular immune responses.Keywords: Hepatitis B virus, Plasmid DNA, Vaccine, Spleen cytokines, Humoral and cellular immune response

Does bacterial colonization influence ureteral stent-associated morbidity? A prospective study

ABSTRACTObjective to evaluate the effect of bacterial colonization on ureteral stent-associated morbidity.Methods This was a prospective study that took place between February 2019 and March 2022. We examined one hundred fifteen patients for ureteric stents application. On the same day of stent removal, the Arabic version of Ureteral Stent Symptoms Questionnaire (USSQ) was used to assess stent-associated morbidity. The stent-associated morbidity and the specificity and sensitivity of culture in the stent and midstream urine were recorded.Results In 15.6% of the patients stent colonization was positive; E. coli was the most common isolated organism. There was no statistically significant difference between sex, age, irrigation fluid volume and duration of operation for stent colonization. However, stent indwelling time was significantly higher in patients with stents with positive cultures. In the colonized stents, there was a statistically significant difference with regards to the total score of USSQ, pain, urinary symptoms, work performance and additional problems of USSQ. Meanwhile, there was no statistically significant difference in the general health and sexual matter.Conclusions stent colonization may be a contributing factor in stent-related morbidity. Stent bacterial colonization increases with the time of stent retention. Stent cultures are not needed as the same microorganisms are detected in urine cultures

Characterisation of the Salmonella Stk Fimbrial Operon and Examination of Stkf, the Putative Adhesion Protein, As a Potential Diagnostic and Vaccine Candidate

The StkF protein of Salmonella enterica serovar Paratyphi A, a putative adhesion-associated protein, was used to develop a candidate adhesin-based vaccine against Salmonella infections, particularly S. Paratyphi A-associated enteric fever. Subcutaneous immunisation of BALB/c mice with recombinant StkF (rStkF) showed that this protein was strongly immunogenic as revealed by the presence of high-titre (1:50,000) anti-StkF antibody in sera from immunized mice. Furthermore, as IgG1 was the major antibody isotype induced, it would appear that rStkF generates a strong Th2-type humoral immune response. The induction of a Th2-dominant immune response was further confirmed by splenocyte-associated cytokine profile analysis which demonstrated greater up-regulation of IL-4 than that of IFN-γ or IL-12-p70. In terms of the protective potential of this antigen, in vitro assays demonstrated that StkF-specific murine antiserum markedly enhanced opsonophagocytosis-mediated uptake of StkF-expressing Salmonella bacteria by human neutrophils. Augmented antibody-specific complement-mediated lysis targeting StkF-expressing Salmonella specifically was also shown. These data suggest a likely direct contribution of StkF-specific antibodies to in vivo killing and clearance of Salmonella and strongly support further investigation of StkF as a potential Salmonella vaccine candidate. BlastN-based interrogation of the NCBI bacterial genome database and PCR investigation of a larger set of strains has shown that the S. Paratyphi A stkF gene and/or the whole stk fimbrial gene cluster is carried by ~1/3 of examined Salmonella serovars. Additionally, bioinformatics and phenotypic characterisation has revealed that the stk fimbrial operon belongs to the chaperone/usher-γ4-fimbrial clade and that it encodes a mannose-sensitive haemagglutinating fimbrial structure. The latter trait is typical of type 1 fimbriae. ELISAs based on rStkF, rStaF and rSipA showed variable sensitivity and specificity for the serodiagnosis of invasive Salmonella infections depending on the particular UK or region-specific cut off applied for each antigen. Further refinement and/or merging of these assays may allow for development of simple and cost effective tests with higher sensitivity and/or specificity than the Widal test. Importantly, despite some minor reactivity with serum from patients with other Gram-negative bacterial infections, the rStkF-based ELISA exhibited no reactivity with serum from patients with dengue fever supporting its potential as a discriminatory diagnostic tool between fevers caused by S. Paratyphi A and dengue virus

Aorto-uni-iliac stent grafts with and without crossover femorofemoral bypass for treatment of abdominal aortic aneurysms: a parallel observational comparative study

We investigated the safety and efficacy of primary aorto-uni-iliac (AUI) endovascular aortic repair (EVAR) without fem-fem crossover in patients with abdominal aortic aneurysm (AAA) and concomitant aortoiliac occlusive disease. 537 EVARs were implemented between 2002 and 2015 in University Hospital Galway, a tertiary referral center for aortic surgery and EVAR. We executed a parallel observational comparative study between 34 patients with AUI with femorofemoral crossover (group A) and six patients treated with AUI but without the crossover (group B). Group B patients presented with infrarenal AAAs with associated total occlusion of one iliac axis and high comorbidities. Technical success was 97% (n = 33) in group A and 85% (n = 5) in group B (P = 0.31). Primary and assisted clinical success at 24 months were 88% (n = 30) and 12% (n = 4), respectively, in group A, and 85% (n = 5) and 15% (n = 1), respectively, in group B (P = 0.125). Reintervention rate was 10% (n = 3) in group A and 0% in group B (P = 0.084). No incidence of postoperative critical lower limb ischemia or amputations occurred in the follow-up period. AUI without crossover bypass is a viable option in selected cases

Screening of quorum sensing and biofilm inhibitors among pseudomonas aeruginosa clinical isolates

Quorum sensing (QS) is a process that enables bacteria to communicate using secreted small pheromone-like signaling molecules called autoinducers (AIs). This process enables a population of bacteria to regulate gene expression collectively. These quorum sensing systems regulates biofilm formation, virulence factors expression, bioluminescence, motility patterns, exopolysaccharide production, antifungal or antibiotic production, endoglucanase production, pigmentation, competence, plasmid conjugal transfer and cross-signaling between strains and species. P. aeruginosa is an important and very dangerous opportunistic pathogen causing many fatal infections in patients with serious medical conditions. P. aeruginosa is associated with nosocomial infections mainly in immunocompromised patients, and it is rated the third-most-common microorganism associated with hospital-acquired infections representing about 10-15% of nosocomial infections recorded globally. Moreover, qRT-PCR revealed a significant reduction in expression of quorum sensing genes in virulence inhibitors-treated P. aeruginosa in comparison with untreated bacteria. Virulence inhibitors could play a role in reduction of Pseudomonas quorum sensing-dependent virulence factors production such as biofilm production, and therefore affect its pathogenesis in the host

Phenotypic and Genotypic Features of Klebsiella pneumoniae Harboring Carbapenemases in Egypt: OXA-48-Like Carbapenemases as an Investigated Model

This study aimed at the characterization of carbapenem-resistant Klebsiella pneumoniae isolates focusing on typing of the blaOXA-48-like genes. Additionally, the correlation between the resistance pattern and biofilm formation capacity of the carbapenem-resistant K. pneumoniae isolates was studied. The collected isolates were assessed for their antimicrobial resistance and carbapenemases production by a modified Hodge test and inhibitor-based tests. The carbapenemases encoding genes (blaKPC, blaNDM, blaVIM, blaIMP, and blaOXA-48-like) were detected by PCR. Isolates harboring blaOXA-48-like genes were genotyped by Enterobacterial Repetitive Intergenic Consensus-Polymerase Chain Reaction (ERIC-PCR) and plasmid profile analysis. The discriminatory power of the three typing methods (antibiogram, ERIC-PCR, and plasmid profile analysis) was compared by calculation of Simpson’s Diversity Index (SDI). The transferability of blaOXA-48 gene was tested by chemical transformation. The biofilm formation capacity and the prevalence of the genes encoding the fimbrial adhesins (fimH-1 and mrkD) were investigated. The isolates showed remarkable resistance to β-lactams and non-β-lactams antimicrobials. The coexistence of the investigated carbapenemases encoding genes was prevalent except for only 15 isolates. The plasmid profile analysis had the highest discriminatory power (SDI = 0.98) in comparison with ERIC-PCR (SDI = 0.89) and antibiogram (SDI = 0.78). The transferability of blaOXA-48 gene was unsuccessful. All isolates were biofilm formers with the absence of a significant correlation between the biofilm formation capacity and resistance profile. The genes fimH-1 and mrkD were prevalent among the isolates. The prevalence of carbapenemases encoding genes, especially blaOXA-48-like genes in Egyptian healthcare settings, is worrisome and necessitates further strict dissemination control measures

Occurrence and Molecular Study of Hypermucoviscous/Hypervirulence Trait in Gut Commensal <i>K. pneumoniae</i> from Healthy Subjects

Hypervirulent Klebsiella pneumoniae (hvKp) is emerging worldwide. Hypermucoviscousity is the characteristic trait that distinguishes it from classic K. pneumoniae (cKp), which enables Kp to cause severe invasive infections. This research aimed to investigate the hypermucoviscous Kp (hmvKp) phenotype among gut commensal Kp isolated from healthy individuals and attempted to characterize the genes encoding virulence factors that may regulate the hypermucoviscosity trait. Using the string test, 50 identified Kp isolates from healthy individuals’ stool samples were examined for hypermucoviscosity and investigated by transmission electron microscopy (TEM). Antimicrobial susceptibility profiles of Kp isolates were determined using the Kirby Bauer disc method. Kp isolates were tested for genes encoding different virulence factors by PCR. Biofilm formation was assayed by the microtiter plate method. All Kp isolates were multidrug-resistant (MDR). Phenotypically, 42% of isolates were hmvKp. PCR-based genotypic testing revealed the hmvKp isolates belonged to capsular serotype K2. All study Kp isolates harbored more than one virulence gene. The genes magA and rmpA were not detected, while the terW gene was present in all isolates. The siderophores encoding genes entB and irp2 were most prevalent in hmvKp isolates (90.5%) and non-hmvKp (96.6%), respectively. hmvKp isolates harbored the genes wabG and uge with rates of 90.5% and 85.7%, respectively. The outcomes of this research highlight the potential health risk of commensal Kp to cause severe invasive diseases, owing to being hmvKp and MDR, and harboring multiple virulence genes. The absence of essential genes related to hypermucoviscosity such as magA and rmpA in hmvKp phenotypes suggests the multifactorial complexity of the hypermucoviscosity or hypervirulence traits. Thus, further studies are warranted to verify the hypermucoviscosity-related virulence factors among pathogenic and commensal Kp in different colonization niches

Glucose concentration affects recombinant interferon a-2b production in Escherichia coli using thermo-induction system

In the present work, a recombinant Escherichia coli strain was used for the production of interferon a-2b in both shake flask and in bioreactor. The first part of this research was focused on the investigation of the effect of glucose concentration on the kinetics of cell growth, recombinant protein production and acetate formation. In general, glucose supplementation to culture medium enhanced cell growth when added in concentration between 0-20 g/L. Further increase in glucose level reduces biomass production and enhances acetate accumulation in culture. The results clearly demonstrated that maximal interferon production of 27.7 mg/L was achieved in culture supplemented with 20 g/L glucose. Further improvement in recombinant interferon production process was also achieved by scaling up from shake flask to 16-L stirred tank bioreactor. The maximal volumetric interferon production in bioreactor batch culture was 44.5. mg/L after only 6 hours