RNA protein kinase SNP at -226 C

BACKGROUND: RNA-dependant protein kinase R (PKR) is a primary mediator in the defence mechanism of interferon against viral replication and pathogenesis during Hepatitis C virus (HCV) infection. In the present study, we have examined the role of Single Nucleotide Polymorphisms (SNPs) in the promoter region of PKR and the serum level of the same protein on the outcome of HCV-infected Egyptian patients. PATIENTS AND METHODS: Genomic DNA was extracted from a total of 135 subjects, including 15 healthy controls, 40 HCV spontaneous resolvers (SRs), and 80 patients with chronic HCV infection. PKR genotyping was assessed using DNA sequencing. Finally, serum levels of PKR, TNF-α, INF-γ, and IL-10 were measured using ELISA technique. RESULTS: Serum levels of PKR, TNF-α, and INF-γ showed a significant increase in SRs as compared to chronic HCV patients. On the other hand, serum levels of IL-10 were significantly higher in chronic HCV patients compared to SRs. The present study demonstrated two novel SNPs in the PKR promoter region: at -226 C/T and -141 C/G. The PKR SNP at -226 C < T correlated with HCV-infected patients (genotype 4a) outcome among Egyptians. Our data showed the unique presence of the TT genotype in SRs group (three patients: 7.5%) in PKR -226 C/T. Interestingly, subjects with the TT genotype were more likely to clear their HCV infection than those with the CC genotype. CONCLUSION: Our work provides more detail about PKR gene polymorphism in HCV genotype 4a as a new clinical tool for anticipating HCV-4a infection outcome.

Impact of IL-27p28 (rs153109) and TNF-α (rs1800629) Genetic Polymorphisms on the Progression of HCV Infection in Egyptian Patients.

BACKGROUND: Hepatitis C virus (HCV) is a universal health problem. HCV infection may proceed to liver fibrosis, cirrhosis, and eventually hepatocellular carcinoma (HCC). The latest is the third leading global cause of cancer-related mortality. Cytokines including IL-27 and TNF-α play a major role as a link between innate and adaptive immunity which in turn deduct the outcome of HCV infection. AIM: The present study examined the role of both (-964 A/G) single-nucleotide polymorphism (SNP) of IL-27p28 rs153109 and (-308 G/A) SNP of TNF-α rs1800629 on the progression of HCV infection in genotype 4a infected patients. PATIENTS AND METHODS: The patients enrolled in the study were divided into three main groups group I: 38 fibrotic patients, group II: 51 cirrhotic patients, and finally group III: 29 HCC patients. Sixteen healthy volunteers were used as controls. IL-27p28 rs153109 and TNF-α rs1800629 genotyping were performed using polymerase chain reaction-restriction fragment length polymorphism assay. RESULTS: There was no statistically significant difference between the studied groups regarding the IL-27p28 genotypes. However, TNF-α (-308) studied polymorphism showed a significant difference between the HCC and fibrosis group (p = 0.00), and also between the cirrhosis and fibrosis group (p = 0.031) revealing that AA genotype is the genotype of risk. Furthermore, the association found between allele frequencies of two studied SNPs and the four studied groups were non-significant. CONCLUSION: TNF-α rs1800629 polymorphism is a potential genetic-susceptibility factor for HCV related cirrhosis and HCC progression.

Extended infusion versus intermittent infusion of imipenem in the treatment of ventilator-associated pneumonia.

BACKGROUND: Mechanical ventilation support can be the main source of ventilator-associated pneumonia (VAP). VAP is a serious infection that may be associated with dangerous gram-negative bacteria mainly, and it leads to an increase in the mortality in the intensive care unit (ICU). Imipenem is one of the strongest antibiotics now available for treating VAP which is associated with gram-negative and gram-positive bacteria, and it belongs to beta-lactam antibiotic group (carbapenem). OBJECTIVE: This study tried to investigate the efficacy of imipenem against VAP when it was infused within 180 min versus the efficacy when it was infused within 30-60 min. SETTING: This study was conducted in main ICU in general hospital which consists of surgical and medical beds within 2 years. One hundred and eighty-seven patients were enrolled on it. METHOD: This study is a retrospective cohort which was conducted within 2 years. The efficacy of imipenem which was administered by intermittent infusion (30-60 min) within first year was compared with the efficacy of imipenem which was administered by extended infusion (180 min) within second year in the field of VAP curing and cost reduction. All data were collected retrospectively from patient medical files and were statistically analyzed by SPSS version 20. MAIN OUTCOME: The study was designed to measure clinical and cost reduction outcomes, mortality and hospital stay. RESULTS: The results indicated that there is a significant decrease in mortality, number of recurrent infection, and ICU stay length, and the number of mechanical ventilator days was associated with extended imipenem infusion during the second year of the study. CONCLUSION: The use of imipenem with extended infusion over 3 hours enhances its clinical outcomes in the treatment of VAP.

Prevalence of methicillin resistant Staphylococcus aureus among Egyptian patients after surgical interventions.

BACKGROUND: Staphylococcus aureus (S. aureus) is isolated frequently from surgical site infections and other soft tissue infections. There are limited data examining the prevalence of methicillin resistant S. aureus (MRSA) among Egyptian patients after surgery. The current study determined the prevalence of MRSA isolated from surgical site and soft tissue infections at Minia University Hospital (MUH), determined their susceptibility to ß-lactams and other antimicrobials, and examined their mecA gene expression. METHODS: A total of 208 hospitalized patients attending the General Surgery Department at MUH were enrolled and all had skin and soft tissue infections (SSTIs) of different causes. These 208 patients (143 males and 65 females) were suffering from surgical site infection (SSI; n=82), diabetic foot (n=52), abscess (n=45), or burn (n=29) infections. Samples were cultured on different media for isolation and identification of S. aureus and the isolates were screened for antibiotic susceptibility. All MRSA isolates were tested by polymerase chain reaction to detect the mecA gene responsible for methicllin resistance. RESULTS: 241 Staphylococcal species represented the most common isolates (64.8%) among 371 collected isolates from the 208 patients. Out of the 241 staphylococcal isolates, 127 were S. aureus (61% of the total patients). The prevalence of S. aureus among SSI, diabetic foot, abscess, and burn patients were 59%, 75%, 56%, and 52%, whereas that of MRSA was 16%, 17%, 13%, and 10%, respectively. MRSA isolates (n=31; 15% of patients) showed multiple resistance to at least one member of the antimicrobial groups tested with an average resistance to 6.6±1.9 antimicrobial groups. Polymerase chain reaction data showed that only 29 isolates of the MRSA isolates (94%) were positive for mecA gene. CONCLUSIONS: Staphylococcus aureus isolates are the major pathogens responsible for wound and surgical site infections at MUH and MRSA are a potential threat for wound patients in Egypt.

Aminoglycoside resistance rates, phenotypes, and mechanisms of Gram-negative bacteria from infected patients in upper Egypt.

With the re-emergence of older antibiotics as valuable choices for treatment of serious infections, we studied the aminoglycoside resistance of Gram-negative bacteria isolated from patients with ear, urinary tract, skin, and gastrointestinal tract infections at Minia university hospital in Egypt. Escherichia coli (mainly from urinary tract and gastrointestinal tract infections) was the most prevalent isolate (28.57%), followed by Pseudomonas aeruginosa (25.7%) (mainly from ear discharge and skin infections). Isolates exhibited maximal resistance against streptomycin (83.4%), and minimal resistance against amikacin (17.7%) and intermediate degrees of resistance against neomycin, kanamycin, gentamicin, and tobramycin. Resistance to older aminoglycosides was higher than newer aminoglycosides. The most common aminoglycoside resistance phenotype was that of streptomycin resistance, present as a single phenotype or in combination, followed by kanamycin-neomycin as determined by interpretative reading. The resistant Pseudomonas aeruginosa strains were capable of producing aminoglycoside-modifying enzymes and using efflux as mechanisms of resistance. Using checkerboard titration method, the most frequently-observed outcome in combinations of aminoglycosides with ß-lactams or quinolones was synergism. The most effective combination was amikacin with ciprofloxacin (100% Synergism), whereas the least effective combination was gentamicin with amoxicillin (53.3% Synergistic, 26.7% additive, and 20% indifferent FIC indices). Whereas the studied combinations were additive and indifferent against few of the tested strains, antagonism was never observed. The high resistance rates to aminoglycosides exhibited by Gram-negative bacteria in this study could be attributed to the selective pressure of aminoglycoside usage which could be controlled by successful implementation of infection control measures.

Effect of ciprofloxacin and N-acetylcysteine on bacterial adherence and biofilm formation on ureteral stent surfaces.

The aim of this study was to evaluate the effect of ciprofloxacin (CIP), N-acetylcysteine (NAC) alone and in combination on biofilm production and pre-formed mature biofilms on ureteral stent surfaces. Two strains each of Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebseilla pneumoniae, Pseudomonas aeruginosa and Proteus vulgaris, recently isolated from patients undergoing ureteral stent removal and shown to be capable of biofilm production, were used in this study. The inhibitory effects of ciprofloxacin, N-acetylcysteine and ciprofloxacin/N-acetylcysteine combination were determined by static adherence assay. Ciprofloxacin (MIC and 2 MIC) and N-acetylcysteine (2 and 4 mg/ml) inhibited biofilm production by > or = 60% in all tested microorganisms. Disruption of pre-formed biofilms of all tested microorganisms was found to be > or = 78% in the presence of ciprofloxacin (MIC and 2 MIC) and > or = 62% in the presence of N-acetylcysteine (2 and 4 mg/ml), compared to controls. Ciprofloxacin/N-acetylcysteine showed the highest inhibitory effect on biofilm production (94-100%) and the highest disruptive effect on the pre-formed biofilms (86-100%) in comparison to controls. N-acetylcysteine was found to increase the therapeutic efficacy of ciprofloxacin by degrading the extracellular polysaccharide matrix of biofilms. These data are statistically significant. The inhibitory effects of ciprofloxacin and N-acetylcysteine on biofilm production were also verified by scanning electron microscope (SEM). In conclusion, Ciprofloxacin/N-acetylcysteine combinations have the highest inhibitory effect on biofilm production and the highest ability to eradicate pre-formed mature biofilms.

Design, synthesis, antibacterial activity and physicochemical parameters of novel N-4-piperazinyl derivatives of norfloxacin.

We report herein the synthesis of some N-Mannich bases in addition to different N-4 substituents of norfloxacin. The antibacterial activities of the newly synthesized compounds were evaluated and correlated with their physicochemical properties. Results revealed that some of the tested compounds exhibited better inhibitory activities than the reference antibiotic norfloxacin against Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia and Staphylococcus aureus strains. Correlation results showed that there is no single physicochemical parameter that can determine the effect of N-4 piperazinyl group on the activity of these fluoroquinolones, where lipophilicity, molecular mass and electronic factors may influence the activity.

Antimicrobial susceptibility profile of Pseudomonas aeruginosa isolates in Egypt.

PURPOSE: Pseudomonas aeruginosa is a leading cause of nosocomial respiratory tract, urinary tract and skin infections. Data are sparse on the antimicrobial resistance of P. aeruginosa in Egypt. We sought to detect and compare the antimicrobial susceptibility of P. aeruginosa isolates from respiratory tract, urinary tract and skin infections at 3 Egyptian hospitals. MATERIALS AND METHODS: Minimum inhibitory concentrations of antibiotics were determined by the agar dilution method. RESULTS: P. aeruginosa respiratory tract infections isolates were 100% resistant to ampicillin, ampicillin/sulbactam, amoxicillin, amoxicillin/clavulanate and chloramphenicol, highly resistant to cefuroxime (89%), tetracycline (89%) and azithromycin (84%), and susceptible to norfloxacin (89%), amikacin (84%) and meropenem (68%). P. aeruginosa urinary tract infection isolates were 100% resistant to ampicillin, amoxicillin, chloramphenicol, cefuroxime and tetracycline, highly resistant to amoxicillin/clavulanate (95%), azithromycin (95%), cefalexin (91%) and ampicillin/sulbactam (82%), and susceptible to amikacin (82%), meropenem (73%) and norfloxacin (64%). P. aeruginosa skin infection isolates were 100% resistant to ampicillin and amoxicillin, highly resistant to tetracycline (95%), amoxicillin/clavulanate (95%), cefalexin (87%) and azithromycin (84%), and susceptible to amikacin (87%), norfloxacin (71%) and meropenem (68%). The anti-pseudomonal effect of antibiotics varied among different infection sites only for ampicillin/sulbactam, cefoperazone or chloramphenicol but not with the other tested antibiotics. CONCLUSIONS: Norfloxacin and amikacin could be used for initial therapy for P. aeruginosa mediated respiratory tract infections. Amikacin, meropenem and norfloxacin could be used for P. aeruginosa mediated urinary tract and skin infections. Such studies are essential to determine the current guidelines for empirical therapy regimens, which vary by location, and help with the establishment of effective infection control measures.

Characterization of Pseudomonas aeruginosa isolated from clinical and environmental samples in Minia, Egypt: prevalence, antibiogram and resistance mechanisms.

OBJECTIVES: To assess the prevalence, levels of antimicrobial susceptibility and resistance mechanisms of Pseudomonas. METHODS: A total of 445 clinical isolates and 200 environmental isolates were collected from three hospitals in Minia, Egypt. The MICs of different antibiotics were determined using the agar dilution method. The isolates were tested for beta-lactamase production and for the presence of efflux pumps. RESULTS: Out of the 445 clinical specimens, 107 Pseudomonas strains (24%) and 81 Pseudomonas aeruginosa strains were isolated (18.2%). Out of the 200 environmental specimens, 57 Pseudomonas strains (28.5%) and 39 P. aeruginosa strains were isolated (19.5%). Amikacin was the most active drug against P. aeruginosa followed by meropenem, cefepime and fluoroquinolones. P. aeruginosa was highly resistant to all other antibiotics tested. The environmental isolates of P. aeruginosa exhibited higher antibiotic resistance than clinical isolates. Mechanisms of resistance used by P. aeruginosa included beta-lactamase production and multiple drug resistance efflux pumps. Our results showed that 29 (36%) of the clinical P. aeruginosa isolates and 37 (95%) of the environmental P. aeruginosa isolates were beta-lactamase producers. In addition, P. aeruginosa isolates effectively used an efflux-mediated mechanism of resistance against ciprofloxacin and meropenem, but not gentamicin or cefotaxime. CONCLUSIONS: This study examined the prevalence of P. aeruginosa, and its susceptibility patterns to different antibiotics. The presence of antibiotic-resistant P. aeruginosa isolates could be attributed to beta-lactamase production and the use of multiple drug resistance efflux pumps.