Silver nanoparticles: A potential antibacterial and antibiofilm agent against biofilm forming multidrug resistant bacteria

Background: Multi-drug resistant (MDR) bacteria are seriously endangering the antibiotics. Different alternative strategies are needed to reinforce antibiotics, of, these; nanostructured materials may play a fruitful role. This study aimed to investigate the antibacterial and antibiofilm activity of silver nanoparticles (AgNPs) against MDR bacteria. Methods: In a cross-sectional study, a total of 33 methicillin resistant Staphylococcus aureus (MRSA) and 52 MDR Pseudomonas aeruginosa (P. aeruginosa) isolates were recovered from intensive care units' (ICUs) admitted patients over a period of 9 months, from December 2017 to August 2018. The antibacterial activity of AgNPs on the clinical isolates of MRSA and MDR P. aeruginosa was assessed by minimum inhibitory concentrations (MICs) using broth microdilution method. The minimum bactericidal concentrations (MBCs) were determined as the lowest concentrations required to kill 99.9% of the initial inoculum. Tissue culture plate method was used to evaluate the antibiofilm activity. Results: The MIC and MBC values ranged from 1 to 16 µg/ml and 2 to 64 µg/ml, respectively. Silver nanoparticles exerted a significant antibiofilm activity against MRSA and MDR P.aeruginosa at all tested concentrations, recording a maximum inhibition value of (82%) and (91%), respectively. Conclusions: AgNPs exhibited a considerable antibacterial and antibiofilm, effect; it could represent a promising weapon in the fight against biofilm forming MDR organisms

Analysis of interleukin-18 and CD14 gene polymorphism in atopic patients

Immunoglobulin E [IgE] mediated allergy is a common chronic disorder resulting from interaction between genetic and environmental factors. We aimed to reveal the single nucleotide polymorphisms' [SNPs] in 1L-18 [137G>C] and CD 14 [C-159T] genes to reveal their possible association with atopic diseases in Egyptian population. A total of 30 diagnosed atopic patients and a total of 30 age-matched control subjects were included in this study. Diagnosis of atopy was made according to the family history and the results of both intradermal skin test and total IgE enzyme- linked immunosorbent assay. Interleukin-18 [-137G>C] genotyping was performed by polymerase chain reaction with sequence specific primers [PCR-SSP] The CD14 [C-159T] polymorphism was detected by polymerase chain reaction -Restriction fragment length polymorphism [PCR-RFLP], Insignificant higher prevalence of heterozygous genotype [GC] of IL-18 [-137G>C] gene was found in atopic patients compared to control subjects. Statistical analysis revealed significant association between atopy and the CC genotype of CD14 [C-159T]. Only the genotype combination GG/ CC which is composed of the IL-18 GG genotype and CD 14 CC genotype was preferentially transmitted to atopic patients. The results of this study suggested a possible association of atopy with the CD 14 [C-159T]. Moreover, the genotype combination GG/ CC may be one of the factors that participate in the. pathogenesis of atopy?

Detection of class 1 integrons-mediated antibiotic resistance among commensal Escherichia coli

Normal intestinal microbiota are a reservoir for resistant genes especially Escherichia coli. The aim of this study was to investigate the prevalence of class 1 integrons and antibiotic resistance in commensal E. coli isolates. Also, this study aimed to detect the association of class 1 integrons with antibiotic resistance [single and multiple drug resistance]. Two hundred E. coli isolates from stools were obtained from different 4 groups [children with and without previous antibiotic treatment and elderly hospitalized and healthy individuals, each group included 50 individuals]. All isolates were tested for their susceptibility against 15 antimicrobial agents using standard disc diffusion method and for the presence of class I integrons by PCR using the following primers; 5'CS: 5'GGCATCCAAGCAGCAAG-3' and 3'CS: 5'AAGCGAC7TGACCTGA-3'. This study revealed that out of the 200 E. coli isolates, III isolates [55.5%] carried class I integrons genes. Comparing children with and without antibiotic treatment, antibiotic-treated ones had a significantly higher frequency of integrons carriage than antibiotic-naïve group [72% versus 64%, P = 0.039]. Evaluating medical interventions, this study detected that the frequency of integrons in E. coli isolates from hospitalized elderly persons was higher compared with non-hospitalized ones [68% versus 18%, P<0.001]. Also, a significant higher frequency of integrons bearing strains was found in antibiotic-naive children than in healthy elderly persons [64% versus 18%, P<0.001]. The majority [82.9%] of isolates were resistant to at least one antimicrobial agent with the following percent resistance, sulfamethoxazole [61%], and trimethoprim-sulfamethoxazole/e [52.5%] ampicillin [40.5%], streptomycin [35%], ampicillin-sulbactam [30%], tetracycline [30%], tobramycin [29%], amikacin [26%] gentamycin [19.5%], nalidixic acid [12.5%] cefuroxime [12.5%], ciprofloxacin [10.5%], cefotaxime [9.5%], cefepime [4.5%] and imipenem [4%]. The most frequent pattern of multidrug resistance E.coli isolates [19.5%] was sulfamethoxazole/e, trimethoprim-sulfamethoxazole/e, ampicillin, and ampicillin-sulbactam. Multiple drug resistance was more frequent in integrons- positive isolates [82.9%] than in integrons-negative E. coli [42. 7%], [P = 0.001]. In conclusion, the prevalence of integrons, n commensal E. coli strains in persons without medical intervention depended on age. Hospitalization and antibiotic administration were influencing factors that affected the frequency of integrons carriage. Human fecal E. coli is a reservoir of antibiotic-resistant genes that has a significant risk of the spread of. microbial resistance in the community

Is genetic polymorphism of ESR1, CYP1A1 and CYP1B1 risk factor for development of uterine leiomyoma?

Uterine leiomyoma is the most common benign smooth muscle tumour of the myometrium. This study was carried out to evaluate the association of ESR1, CYP1A1 and CYP1B1 polymorphism with uterine leiomyoma in Egyptian women. The study population consisted of 160 patients with uterine leiomyoma and 100 healthy women as control. All patients and control were matched as regards age, height, weight, number of parity and oral contraceptives. The genetic polymorphisms were analysed by polymerase chain reaction restriction fragment length polymorphism [PCR-RFLP] using the following primers. For ESR1 MSP1 exon 1, [forward, 5'-CTGCCACCCTATCTGTATCTTTTCCTATTCTCC-3'; reverse, 5'TCTTTCTCT-GCCACCCTGGCGTCGATTATCTGA-3']. For CYP1A1 Ile462 val [A/G], [forward, 5'-GATCTGAGTTCCTACCTGA-3'; Reverse, 5'-TAGCGTCCAAGAG-AAAGACCTCCCAGCGCTCAA-3']. For CYP1B1 Leu432Val [C/G], [Forward, 5'CACCA-CTGCCAACACCTCTGTC3', reverse 5'-AGTTCTCCGGGTTAGGCCACTTAA-3']. The results of this work revealed that there was no statistically significant differences overall associations between the ESR1 exon I C/T genotypes and uterine leiomyoma [P=0.67]. However, an elevated risk of uterine leiomyoma was observed among women with the CYP1A1 Ile462 val A/G genotype [P=0.01] and CYP1B1 Leu 432 val C/C genotype [P=0.027]. From this study, we can conclude that the carriage of CYP1A1 Ile462 val A/G and CYP1B1 Leu 432 val C/C genotypes predict the susceptibility to leiomyoma in Egyptian women and they are likely to contribute in the pathogenesis of leiomyoma

Do embryo implantation and subsequent pregnancy depend on follicular fluid cytokines in IVF cycles?

Background: The aim of this study was to detect the presence of interleukin [IL]-1B, tumour necrosis factor [TNF]-alpha, IL-6, IL-12 and IL-13 in follicular fluid and the relation between concentration of selected cytokines and in vitro fertilization [IVF] outcome

Methods: Follicular fluid [FF] from 87 women was obtained during oocyte retrieval for IVF. The concentrations of the five cytokines were measured in FF by cytokine-specific enzyme-linked immunosorbent assays and their concentrations were compared between women who became pregnant and those who failed to get pregnancy. Twenty patients had male factor infertility, 23 with tubal factor infertility, 19 had unexplained infertility and 25 patients with ovarian factor infertility

Results: IL-13 was absent in the peri-ovulatory FF of all patients. Twenty five patients achieved pregnancy, while 62 did not. Both groups of pregnant and non-pregnant women were compared regarding to age, duration of infertility, ovarian stimulation parameters, fertilization rates, number of arrested and transferred embryos and there was no significant difference between the two groups [P>0.05]. Concentrations of FF IL-1B and TNF-alpha were not significantly different between pregnant and non-pregnant cycles. Concentrations of FF IL-6 were significantly higher in pregnant compared with non-pregnant women [P<0.001]. On the other hand, concentration of FF IL-12 were significantly lower in pregnant than in non-pregnant women [P<0.001]. None of the studied cytokines was a predictor of good or poor-quality of an embryo [P>0.05]

Conclusion: Interleukin-6 and IL-12 are important cytokines that may affect IVF outcome. Higher concentrations of IL-6 and lower concentrations of IL-12 in peri-ovulatory FF may predict IVF success

Adenovirus and respiratory tract infection in young children

This study was conducted on 115 infants and preschool children [65 males and 50 females] complained from different respiratory symptoms. Their ages ranged from 2 months to 5 years old. They were subjected to history taking, clinical and chest examinations. Moreover samples from transnasal endotracheal tube were collected. From all investigated children, 28 cases [24.3%] proved to be infected with different bacterial causes by direct culture on different media. Streptococcus pneumonia, Staph. aureus and Strept. pygoges were the predominant pathogens. Adenovirus [Ad] was detected by enzyme-linked immunosorbent assay [ELISA] in 25.3% and by immune-electron microscope [IEM] in 23% of the cases. Different clinical data were recorded in this study, high temperature [38.5-39.5°C], expectoration and cough were the most significant positive data. Ad-infections occurred among all age groups with higher prevalence in older age [13- 24 months and >24 months]. Infection was predominant among females more than males with a significant statistical difference. Ad-infection was recorded all over seasons of the year but no statistical significant difference was recorded. Regarding the relationship between Ad and different forms of respiratory infections, acute bronchitis and pneumonia were the significant diagnosis. On recoding the validity test of ELISA in comparison to IEM, it shows 81.8% sensitivity and 96.9% specificity, while there were 93.1% agreement between the two tests and only 6.9% disagreement. On conclusion ELISA and IEM are rapid and useful methods for detection of Ad-infections

Detection of rotavirus G and P genotypes among children with acute gastroenteritis

Rotavirus gastroenteritis is a leading cause of diarrheal disease mortality among children under five years, mostly in developing world. This study aimed to detect rotavirus among 40 hospitalized infants and children with acute gastroenteritis whose ages ranged from 2-24 months, 22 males and 18 females. Also, a control group of 15 healthy infants and children with a matched age and sex were included in the study. Three different commercial tests for detection of group A rotavirus [Latex agglutination [LA], enzyme linked immunosorbent assay [ELISA] and reverse-transcriptase PCR [RT-PCR]] were used to evaluate fecal specimens obtained from the patients and control group. LA test detected the virus in 24 cases [60%], while the result was 19 cases [47.5%] with ELISA and only 17 cases [42.5%] with RT-PCR. Genotyping showed presence of VP4 gene [P genotype] in 8 cases, VP7 [G genotype] in 6 cases, and a mixed VP4 and VP7 [P and G genotypes] in 3 cases of PCR positive diarrheal samples. The severe clinical manifestations were associated with VP7 genotype. Infection was more in artificial fed infants than breast fed with a significant difference [P <0.05]. Also, infection was more frequent in winter season. Considering PCR as a gold standard, our study reported that ELISA and LA test had a sensitivity of 94.1% and 82.4% respectively and a specificity of 92.1% and 73.7% respectively. In conclusion, ELISA is rapid, sensitive and specific test for detection of rotavirus in stool samples, while RT-PCR is an important method for viral genotyping

Phenotyping and genotyping of pseudomonas aeruginosa urine isolates in Zagazig University Hospitals

Pseudomonas aeruginosa [P. aeruginosa] is an important nosocomial pathogen. therefore sensitive typing techniques are required for its control. Seventy six isolates of P.aeruginosa were recovered from midstream urine specimens obtained from the different Departments in the Zagazig University Hospitals [ZUHs]. Five isolates were polymorphic while the remaining 71 isolates were unimorphic. Different morphotypes of the same isolates were studied separately. In addition, 10 environmental isolates were obtained from the wards of the Urology Department. All isolates and their morphological variants were characterized by morphotyping on primary isolation, biochemical reactions using API 20 NE system, serotyping, antimicrobial susceptibility typing and genotyping using enterobacterial repetitive intergenic consensuspolymerase chain ration [ERIC-PCR] and random amplification of polymorphic DNA [ RAPD] using API2H primer. The unimorphic clinical and environmental isolates belonged to morphotype 1 [56.3% and 60%, respectively], morphotype 2 [22.5 % and 30%, respectively] and morphotype 4 [19.7% and 10%. respectively]. For the clinical and environmental isolates, including morphological variants, 14.1% and 30%, respectively showed atypical biochemical reactions. All were esculin positive. Forty seven percent of the clinical isolates and variants were serologically typable and none of the environmental isolates was typable. Among the typable clinical isolates and variants, serotypes 4 [17.1%] and 6 [7.9%] were the commonest. All isolates could be grouped under 14 antimicrobial susceptibility types. ERIC-PCR yielded 31 typing patterns. Twenty one patterns comprised the clinical isolates and their morphological variants, and 10 patterns comprised the environmental isolates. RAPD by API2H primer yielded 13 types for both clinical and environmental isolates. We concluded that ERIC-PCR was the most discriminatory of all the phenotypic and molecular methods used in this study for typing P.aeruginosa. On the other hand, RAPD using API2H primer seems to be useful for further subtype isolates of the same ERIC pattern. Furthermore. P.aeruginosa isolates of the same genotype can be discriminated by using phenotypic methods like serotyping and antimicrobial susceptibility typing. Interestingly, the majority of morphological variants obtained on primary culture from the same midstream urine samples may represent different strains rather than phenotypic plasticity of the same strain. Therefore, antibiograms should be performed separately for such colonial variants. Moreover, in our study, the environmental isolates of P. aeruginosa played a little role, if any, in the spread of P. aeruginosa nosocomial urinary tract infection