Uropathogenic Escherichia coli(UPEC)is the leading cause of urinary tract infections in women,causing significant morbidity and mortality in this population.Adherence to host epithelial cells is a pivotal step in the ...Uropathogenic Escherichia coli(UPEC)is the leading cause of urinary tract infections in women,causing significant morbidity and mortality in this population.Adherence to host epithelial cells is a pivotal step in the pathogenesis of UPEC.One of the most important virulence factors involved in mediating this attachment is the type 1 pilus(type 1 fimbria)encoded by a set of fim genes arranged in an operon.The expression of type 1 pili is controlled by a phenomenon known as phase variation,which reversibly switches between the expression of type 1 pili(Phase-ON)and loss of expression(Phase-OFF).Phase-ON cells have the promoter for the fimA structural gene on an invertible DNA element called fimS,which lines up to allow transcription,whereas transcription of the structural gene is silenced in Phase-OFF cells.The orientation of the fimS invertible element is controlled by two site-specific recombinases,FimB and FimE.Environmental conditions cause transcriptional and post-transcriptional changes in UPEC cells that affect the level of regulatory proteins,which in turn play vital roles in modulating this phase switching ability.The role of fim gene regulation in UPEC pathogenesis will be discussed.展开更多
<span style="font-family:;" "=""><span style="font-family:Verdana;">The uropathogenic </span><i><span style="font-family:Verdana;">Staphylococ...<span style="font-family:;" "=""><span style="font-family:Verdana;">The uropathogenic </span><i><span style="font-family:Verdana;">Staphylococcus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> is reported severally to be resistant to the drugs often used empirically for treatment of urinary tract infections (UTIs). Their ability to exhibit resistance to multiple drugs is a great de</span><span style="font-family:Verdana;">al of threat to successes recorded in the management of UTIs cause</span><span style="font-family:Verdana;">d by this pathogen. Lactic acid bacteria (LAB) have been demonstrated to exhibit an</span><span style="font-family:Verdana;">timicrobial activities but studies about their prospect against multi</span><span style="font-family:Verdana;">-drug resistant </span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> are quite few. This study therefore investigated acti</span><span><span style="font-family:Verdana;">vities of LAB against the multi-drug resistant </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> recover</span></span><span style="font-family:Verdana;">ed fro</span><span style="font-family:Verdana;">m urine samples of symptomatic women. The three differ</span><span style="font-family:Verdana;">ent species of LAB </span><span><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 62, </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 86 and </span><i><span style="font-family:Verdana;">Weis</span></i></span><i><span style="font-family:Verdana;">sella</span></i><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> BTA 40) previously isolated and identified by 16S rRNA s</span><span style="font-family:;" "=""><span style="font-family:Verdana;">e</span><span style="font-family:Verdana;">quencing were selected based on their history of antimicrobial activities. Their</span><span style="font-family:Verdana;"> m</span><span style="font-family:Verdana;">etabolites were employed in the antagonistic assays against six (6) mu</span><span style="font-family:Verdana;">lti-drug resista</span><span style="font-family:Verdana;">nt test pathogens recovered fro</span><span style="font-family:Verdana;">m urine samples of symptomatic, non-pregnant women attending clinics in Lagos, Nigeria and the control (</span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> subs bovis strain DSM 18669) following standard procedures. </span><span style="font-family:Verdana;">The pathogens showed resistances to almost all the antibiotics except</span><span style="font-family:Verdana;"> levofloxaci</span><span style="font-family:Verdana;">n, ciprofloxacin, imipenem while the control showed resistance to thr</span><span style="font-family:Verdana;">ee. The LAB, </span><i><span style="font-family:Verdana;">L.</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> inhibited five (83.3%) of the pathogens with zone diameter of 12 - 17 mm, followed by </span><i><span style="font-family:Verdana;">W</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> inhibiting three (50%) with 15 - 17 mm. </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> on the other hand, inhibited a pathogen and the control with zones of 13 mm and 14 mm respectively. In conclusion, the extracted metabolites of LAB inhibited the growth of multi-drug resistant clinical isolates of uropathogenic </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> and may therefore be potent alternatives to antibiotics.</span></span>展开更多
Objective:To scrutinize patterns of multi-drug-resistant uropathogenic Escherichia coli(UPEC) strains and particularly of fluoroquinolone-resistance this is an alternative choice for the treatment of urinary tract inf...Objective:To scrutinize patterns of multi-drug-resistant uropathogenic Escherichia coli(UPEC) strains and particularly of fluoroquinolone-resistance this is an alternative choice for the treatment of urinary tract infections.Methods:Bacterial samples(n = 250) were collected from out-patients from August 2012 to August 2014 Islamabad.Antibiotic susceptibility profiling and determination of minimum inhibitory concentrations(MICs) and minimum bactericidal concentrations were performed according to the guidelines of Clinical and Laboratory Standards Institute(CLSI,2012).Genes,qnrA,qnrB and qnrS were identified by DNA amplification and sequencing.Results:The highest percentage of UPEC isolates were resistant to co-trimoxazole(82%) followed by cephalothin(80%),2nd Gen,3rd Gen and 4th Gen cephalosporins,respectively.Resistance against gentamicin,amikacin remained 29% and 4%.For other drugs including nitrofurantoin,tetracycline,carbapenem and beta-lactam inhibitors remained below 10%.Altogether,59% of the isolates were resistant to at least three antibiotics including one fluoroquinolone.Overall,MICs for ciprofloxacin remained(MIC≥256 μg/mL) and for levofloxacin(MIC≥16 μg/mL and 32 μg/mL).No significant differences were observed regarding MIC values of extended spectrumβ-lactamase(ESBL) and non-ESBL producers.For qnrS and qnrB positive isolates MICs remained above 32 μg/mL.Prevalence of UPEC was significantly higher among females and 40% of the isolates were ESBL producers.Conclusions:Higher percentages of ESBL producing UPEC were associated with urinary tract infections.Moreover,the majority of these isolates were multi-drug resistant and fluoroquinolone-resistant.展开更多
Objective:In the present study we try to correlate between pathogenic intrinsic factor of Escherichia coli(E.coli) presented with different fimbria genotyes and biofilm formation with host immune factor entitled inter...Objective:In the present study we try to correlate between pathogenic intrinsic factor of Escherichia coli(E.coli) presented with different fimbria genotyes and biofilm formation with host immune factor entitled interleukin-6(IL-6) secretion as defense mechanism.Methods:A total of 91 pediatrics complaining of pyuria were included in the present study.In addition,20 healthy control children were included.Full microbiological study was performed for isolated E.coli.PapC alleles were studied by multiple alleles PCR and biofilm formation was studied.IL-6 was measured in urine.Results:IL-6 had statistically significant elevation in patients’urine compared to control.From biofilm study, it was found that 19 isolated E.coli had formed biofilm in vitro.Moreover,urine samples with positive biofilm formation of E.coli had statistically significant lower IL-6 secretion than those with negative E.coli for biofilms.The distribution of fimbria genotypes showed that the frequent genotype was for alleleⅠ(34.3%) followed by mixed allelesⅠandⅡ(24.1%).There was significant correlation between mixed alleles(Ⅰ&Ⅱ)and biofilm formation.Conclusion: The present study highlights the presence of significant strains of E.coli causing urinary tract infections capable of biofilm formation.Biofilm formation is associated with less innate immunity manifested by lower urinary IL- 6.The majority of isolates had fimbria genes.It appears that mixed allelesⅠandⅡhave prominent virulence effect with tendency for biofilm formation.展开更多
Objective: To deal with the anti-uropathogenic and in silico screening of(E-)-N'-(substitutedbenzylidene)-2-(quinolin-8-yloxy)acetohydrazide analogues in order to search the potential anti-uropathogenic agents.Met...Objective: To deal with the anti-uropathogenic and in silico screening of(E-)-N'-(substitutedbenzylidene)-2-(quinolin-8-yloxy)acetohydrazide analogues in order to search the potential anti-uropathogenic agents.Methods: Three(E-)-N'-(substituted-benzylidene)-2-(quinolin-8-yloxy)acetohydrazide analogues were synthesized. Structure elucidation was done using various spectroscopic techniques including infrared radiation, 1hydrogen-nuclear magnetic resonance, carbon-13 nuclear magnetic resonance, etc. Physicochemical score, bioactivity score and molecular docking studies were carried out using Lipinski's rule of five, Molinspiration(web based software), Autodock 4.2 tools. In vitro anti-uropathogenic activity was carried out against four pathogens named as Staphylococcus aureus(S. aureus), Staphylococcus epidermidis, Proteus mirabilis and Escherichia coli by disc diffusion method and macro-dilution test following their morphological and biochemical characterization.Results: The formation of(E-)-N'-(substituted-benz ylidene)-2-(quinolin-8-yloxy)acetohydrazide is confirmed from the spectroscopic results. All the compounds were found in compliance with Lipinski's rule of five and exhibited bioactivity score from-0.50 to 0.00. Docking results revealed that compound-1 is forming one hydrogen bond with TYR 576 and two hydrogen bond with GLU 569, while compound-2 is forming one hydrogen bond with ARG 599, and compound-3 forming 0 hydrogen bond. The anti-uropathogenic evaluation exhibited that compound one exhibited better activity against S. aureus, while it was found to possess moderate to good activity against both Gram-positive bacteria and Gram-negative bacteria excluding S. aureus.Conclusions: Our study revealed that compound one exhibited better activity than the standard in case of S. aureus and moderate to good activity against rest of the pathogens. Molecular docking, physicochemical and bioactivity studies strongly supported the experimental results. From the well obtained results it was concluded that compound-1 can lead as potential antiuropathogenic agents.展开更多
As the lumen of the prostatic urethra becomes compromised by fibroadenomatous growth in the periurethral region of the prostate of men with Benign prostatic hyperplasia (BPH), urine outflow is obstructed progressively...As the lumen of the prostatic urethra becomes compromised by fibroadenomatous growth in the periurethral region of the prostate of men with Benign prostatic hyperplasia (BPH), urine outflow is obstructed progressively resulting in incomplete bladder empting causing stasis and may predispose patients to infection. Mid stream urine samples were collected from 94 BPH patients. Macroscopy, microscopy, culture and antibiotic susceptibility test were carried out on isolated uropathogens. Isolated bacteria were characterized using biochemical tests. Isolated bacterial pathogens include Proteus mirabilis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella oxytoca, Morgarella morgani, K. pneumonia and Enterococcus faecalis in order of frequency. The isolates show highest resistance of 87.1% to Ciprofloxacin and least resistance of 12.9% to Imipenem. The isolates were found to be multi-drug resistant and the 12.9% resistance to Imipenem suggests presence of Carbapenemase producing bacteria among the isolates.展开更多
Urinary tract infections (UTI) are very common in all the developed as well as developing countries in which the majority of infections are catheter associated. Catheter associated urinary tract infections (CAUTI) is ...Urinary tract infections (UTI) are very common in all the developed as well as developing countries in which the majority of infections are catheter associated. Catheter associated urinary tract infections (CAUTI) is one of the major causes of hospital acquired infections. The aim of this study is to investigate influential demographic factors responsible for contamination associated with the rate of CAUTI, while taking into account type of urinary catheter used, the most common organisms found, patient diagnosis, age, gender, and comparison with other studies. During the study, 22 uropathogenic species were isolated from the different segments of urinary catheter samples of the patients collected from 12 different hospitals of Amravati city, Maharashtra, India from January 2015 to 2018. Gram negative organisms were the most frequent isolates, with <i>Pseudomonas aeruginosa</i> (16.08%) being the most common followed by <i>Escherichia coli</i> (10%) and <i>Candida albicans</i> accounted for almost 11% of all the uropathogens. It was found that the majority of uropathogens were isolated from the section A (Catheter segment inside the bladder) and section E (Catheter segment connected to drainage tube) of the urinary catheter. The duration of the catheterization plays the major role in the contamination and further infection to continue. It was observed that the female catheterized patients are more prone to the contamination and infection as compared to male catheterized patient. The antibiotic sensitivity pattern indicates that MAR (Multiple Antibiotic Resistance) index was more than 0.2 for almost all the uropathogens tested concluding that there is antibiotic stress on uropathogens and rate of resistance increased rapidly. Also it was found that there was a statistically significant association between the duration of catheterization, type of disease, age of patient and type of catheter with respect to gender.展开更多
Background: Urinary tract infection (UTI) is a severe public health issue that affects a wide range of people around the world with Klebsiella pneumoniae accounting for up to 25% of all urinary tract infections. The h...Background: Urinary tract infection (UTI) is a severe public health issue that affects a wide range of people around the world with Klebsiella pneumoniae accounting for up to 25% of all urinary tract infections. The higher rate of UTI associated with uropathogenic Klebsiella species has been associated with the emergence of hypervirulent and antibiotic-resistant strains facilitated by the misuse and overuse of antibiotics as well as other sociodemographic and behavioural practices of susceptible individuals. This study was aimed at investigating the prevalence and associated risk factors of uropathogenic Klebsiella species in Port Harcourt, Nigeria. Methodology: The study employed a descriptive cross-sectional study design comprising 300 subjects clinically suspected of having urinary tract infections attending the Rivers State University Medical Centre and the Rivers State University Teaching Hospital between March to August 2022. A standard urine culture procedure was used to ascertain significant bacteriuria after which Klebsiella colonies were isolated and identified using standard bacteriological techniques. The data generated from this study was represented as frequency and percentages, and inferential statistics were carried out using Chi-square with the aid of GraphPad Prism Software Version 9. Statistical significance was defined as a p-value of less than 0.05 at a 95% confidence interval. Result: The prevalence of uropathogenic Klebsiella sp. was 16%, with sex, pregnancy status, and religion of the individuals substantially linked (p p Klebsiella species. Conclusion: This study reports a relatively high prevalence of uropathogenic Klebsiella species at 16%, with the sex and pregnancy status of the subjects being significantly associated (p Klebsiella species in the current study. Health promotion and awareness efforts should be prioritised to inform susceptible demographics about their risks for urinary tract infections associated with uropathogenic Klebsiella species via targeted educational campaigns, collaboration with healthcare providers, use of social media and online platforms, workplace wellness programs, and community outreach programs amongst others. Antimicrobial susceptibility testing before prescriptions and treatment should be emphasized and upheld in all clinical settings.展开更多
Haematuria is the presence of red blood cells in urine. It is most often caused by urinary tract infections of which Escherichia coli is frequently implicated. Impairment of kidney functions could occur as a result of...Haematuria is the presence of red blood cells in urine. It is most often caused by urinary tract infections of which Escherichia coli is frequently implicated. Impairment of kidney functions could occur as a result of infection or other complications of the kidney. The aim of the study was to determine the prevalence of uropathogenic Escherichia coli among adult male patients with haematuria and impaired kidneys attending a general hospital in Benue state. Three hundred and sixty-eight (368) samples of urine were collected from 368 male patients (≥ 40 years) attending the 23 general hospitals in Benue state. Each of the urine samples was divided into two parts for haematuria and isolation and identification of Escherichia coli. Blood samples (368) were also collected from the patients and used for quantitative determination of creatinine and estimation of glomerular filtration rate. The presence of haematuria was 45.1% and ranges from 12.5% to 100%. Prevalence of haematuria with respect to age shows that patients within the age group of 90 - 99 years had the highest rate (100%) and the least were those within the ages of 40 - 49 years (20.0%). Isolation rate of uropathogenic Escherichia coli was 16.3% and ranged from 6.3 to 37.5%. Patients within the age group of 90 - 99 years had the highest elevated impaired renal function of 4 (80%), followed by patients within the ages of 80 - 89 years [17 (77.3%)] and the lowest were those within the ages of 40 - 49 [6 (10.0%)]. The overall presence of haematuria in the patients was high (45.1%) with similar high Escherichia coli isolation rate and impaired renal function which could mean that acute or chronic kidney disease may set in.展开更多
Urinary tract infections (UTIs) are common infections caused by normal skin or rectum bacteria that get into the urethra and infect the urinary tract. Although the infection can affect various parts of the tract, blad...Urinary tract infections (UTIs) are common infections caused by normal skin or rectum bacteria that get into the urethra and infect the urinary tract. Although the infection can affect various parts of the tract, bladder infections are the most prevalent kind. Uropathogenic Escherichia Coli (UPEC) is the most common pathogen associated with UTI development. Therefore, inhibiting the UPEC protein target (PDB ID: 8BVD) appears to be a promising therapeutic strategy. Therefore, in this study, molecular docking and dynamics were conducted to examine the antibacterial activity of Aloe barbadensis miller against UPEC bacteria. The Aloe barbadensis miller natural compounds licochalcone A, palmidin B and palmidin C were downloaded from PubChem with amoxicillin, which was used as a control drug and studied against the target molecule. The potential parameters examined were the docking scores, absorption, distribution, metabolism, excretion, toxicity (ADMET), bioavailability, root mean square deviation (RMSD), root mean square fluctuation (RMSF), hydrogen bonding, radius of gyration, and potential energy of the system. Docking scores showed that all ligands demonstrated an admirable candidature as an inhibitor to 8BVD molecule, and the score hierarchy is licochalcone A (-6.4 kcal/mol), palmidin C (-6.1 kcal/mol), palmidin B (-6.0 kcal/mol), and amoxicillin (-5.9 kcal/mol). All ligands appeared to have good drug-like properties and oral bioavailability. Molecular dynamic studies showed that all ligands exhibited an excellent nominee as inhibitors in their vicinity at 20 ns. However, there is a relatively high fluctuation of palmidin B compared with other compounds, which seems to be more stable. This work suggests that the selected phytoconstituents could be used as inhibitors of the 8BVD protein in the fight against UTIs. However, further investigation on the clinical and experimental validation of UTI treatment’s specific mechanisms and effects is still welcomed.展开更多
Urinary tract infection (UTI) is a frequent pathology among HTLV-I+ individuals being capable of severely compromising the kidneys and bladder. Molecular characteristics of uropathogenic Escherichia coli (UPEC) from H...Urinary tract infection (UTI) is a frequent pathology among HTLV-I+ individuals being capable of severely compromising the kidneys and bladder. Molecular characteristics of uropathogenic Escherichia coli (UPEC) from HTLV-I+ infected individuals are unknown. UPEC isolates from HTVL-I+ individuals, with and without clinical symptoms of myelopathy, were submitted to genetic typing seeking to infer bacterial diversity and potential virulence. 71 bacterial isolates were characterized according to random amplified polymorphic DNA and phylotypes. Phylotyping classified E. coli into four phylogenetic groups: A (18.3%), B1 (16.9%), B2 (39.4%), and D (25.3%) and 8 phylotypes according to the presence of the genetic sequences chuA, yjaA and the DNA fragment TSPE4.C2: ﹣﹣﹣ (5.6%) and ﹣+﹣ (12.6%) in phylogroup A, ﹣﹣+ (7.0%) and ﹣++ (9.8%) in B1, +++ (32.3%) and ++﹣ (7.0%) in B2, +﹣﹣ (15.4%) and +﹣+ (9.8%) in D. The B2 phylogroup was the most prevalent among HTLV﹣ associated myelopathy and asymptomatic individuals. RAPD-PCR typing revealed a high degree of bacterial polymorphism indicating a non-clonal origin. Genotypes were not found to be distributed according to clinical status or epidemiological features. Our results lead us to suggest that the neurological impairment in HTLV-I+ individuals can be a risk factor for urinary infections due E. coli which are caused by distinct bacterial lineages.展开更多
Human primary epithelial cells of renal pelvis was established to investigate the adherence of uropathogenic Escherichia coli （UPEC） to this cell line, in which the primary cell culture was performed by using cultiv...Human primary epithelial cells of renal pelvis was established to investigate the adherence of uropathogenic Escherichia coli （UPEC） to this cell line, in which the primary cell culture was performed by using cultivation of the normal epithelium of renal pelvis in keratinocyte serum free medium （K-SFM） with epidermal growth factor （EGF） and bovine pituitary extract （BPE）. Both UPEC132 obtained from urine specimen of patients with pyelonephritis and the pilus-free representative strain E. coli K-12p678- 54 were used to study the adherence of these strains on human primary epithelial cells of renal pelvis. The UPEC adherence was performed with observation on the morphological changes of the adhered cells, while the adhesion rates and indices were calculated in different times of experiment. In addition, the virulence genes hly and cnfl of UPEC132 were detected by multiplex PCR assay. In this study, the human primary epithelial cells of renal pelvis was found to exhibit the character of the transitional epithelial cells. Compared with the control group, the adhesion rates and indices began to increase from 15 min of the experiment time and reached its peak in 120 min. The adhesion rate and index of UPEC132 to human primary epithelial cells of renal pelvis were 74.4% and 34.0 respectively. Many microscopic changes in the primary cells adhered with UPEC132 could be detected, such as rounding or irregularity in shape, unevenness in staining and the cytoplasmic and nuclear changes. It suggests that human primary epithelial cells of renal pelvis can be used for the experiment on UPEC adhesion, thus providing a basis for the further study on the pathogenesis of UPEC.展开更多
Objectives： To investigate the resistance and virulence profiles of uropathogenic Escherichia coli（UPEC） and its treatment by Chinese medicine（CM） Fuzheng Qingre Lishi Formula（扶正清热利湿方, FQLF）. Methods： U...Objectives： To investigate the resistance and virulence profiles of uropathogenic Escherichia coli（UPEC） and its treatment by Chinese medicine（CM） Fuzheng Qingre Lishi Formula（扶正清热利湿方, FQLF）. Methods： UPEC strains were isolated from recurrent urinary tract infections（UTIs） patients. Patient sensitivities to 17 antibiotics were tested by the disk diffusion method. Virulence genes were screened by plolymerase chain reaction. A mouse model was constructed using a multi-drug resistant and virulent UPEC strain and treated with FQLF or the antibiotic imipenem. The treatment efficacy was evaluated by bacterial clearance from urine and the urinary organs. Results： A total of 90 UPEC strains were collected, and 94.4% of the isolates were resistant to at least 1 antibiotic. Approximately 66.7% of the UPEC strains were multi-drug resistant. More than one virulence gene was found in 85.6% of the isolates. The extended-spectrum β-lactamases（ESBL）-positive strains were more resistant than the negative ones. The virulence gene number was positively correlated with the resistance number（P〈0.05）. A mouse model was successful y constructed using UPEC10. Treatment with either FQLF or antibiotics significantly cleared bacteria from the mouse urine after 14 days. In the untreated control, the bacteria lasted for 28 days. FQLF treatment of the UTI mouse model greatly reduced the bacterial number in the kidney and bladder, but could not completely clear the bacteria. Conclusions： Multi-drug resistance is common among UPEC isolates, and the resistance is positively related with virulence. FQLF could treat UPEC UTIs, but could not completely clear the bacteria from the host.展开更多
Adhesion of P-type and type-1 fimbriated uropathogenic E.coli(UPEC)to uroepithelial cells initiates urinary tract infections(UTIs).This research aimed to evaluate the capacities of selected cranberry polyphenols and t...Adhesion of P-type and type-1 fimbriated uropathogenic E.coli(UPEC)to uroepithelial cells initiates urinary tract infections(UTIs).This research aimed to evaluate the capacities of selected cranberry polyphenols and their microbial metabolites to inhibit such adhesion in vitro using a modified fluorometric method.Data showed that the inhibition capacity of myricetin increased with concentration and plateaued at 70%.It had IC50 values of 13.2μM against P-type E.coli and 5.50μM against type-1 E.coli.Quercetin showed similar anti-adhesion capacities to myricetin.Procyanidin A2 and B2 had weaker anti-adhesion activities than myricetin and quercetin,with maximal inhibition capacities of 20%-30%against UPEC.Hippuric acid,a major metabolite of cranberry polyphenols in human urine,showed a maximal inhibition of 20%at 558μM against type-1 E.coli adhesion,whereas no anti-adhesion activity against P-type E.coli was detected.The fractions of cranberry fruit powder enriched with proanthocyanidin polymers showed the highest anti-adhesion activities compared to the fractions enriched with anthocyanins,flavonols,or proanthocyanidin oligomers.Overall,the anti-adhesion activities of cranberry polyphenols and metabolites depend on their structures and the types of fimbriae on E.coli.展开更多
Objective:To determine the extended-spectrum beta-lactamase(ESBL)production and prevalence of bla_(CTX-M-1),bla_(SHV)and bla_(TEM)genes among uropathogenic Escherichia coli(UPEC)isolates from 3 military hospitals of T...Objective:To determine the extended-spectrum beta-lactamase(ESBL)production and prevalence of bla_(CTX-M-1),bla_(SHV)and bla_(TEM)genes among uropathogenic Escherichia coli(UPEC)isolates from 3 military hospitals of Tehran during 2015-2016.Methods:One-hundred and eleven isolates were adopted.The antibiotic susceptibility testing was conducted according to Clinical and Laboratory Standards Institute guidelines.The combine disk was used for phenotypic ESBL production.The ceftazidime MIC was conducted with the micro-broth dilution test.The PCR assay was used to detect the bla_(CTX-M-1),bla_(SHV)and bla_(TEM)genes.Results:In the broth microdilution method,103(92.7%)isolates showed minimal inhibitory concentration(MIC)≥1μg/mL,and also in the combined disk method,89(80.1%of all)were ESBL positive.On the other hand,among 91 ceftazidime resistant isolates,86(77.4%of all)were ESBL positive.The difference between the two methods for ESBL confirmation was not significant.The result of MIC was similar to the disk diffusion method in the detection of phenotypic ESBL production.Among ESBL producer isolates,the prevalence of bla_(CTX-M-1),bla_(SHV)and bla_(TEM)was 77.4%(n=86),47.4%(n=53)and 2.4%(n=2),respectively.These genes were amplified in a wide range MIC of ceftazidime.Conclusions:The prevalence of multi-drug resistant UPEC and ESBL positive isolates was high in military hospitals.The majority of UPEC isolates amplified bla_(CTX-M-I)and bla_(SHV)typeβ-lactamase genes.One-third of isolates were positive in presence of both these genes.There was no relation between ceftazidime MIC and presence of beta-lactamase genes.展开更多
Studying the interaction between uropathogenic Escherichia coli (UPEC) and uroepithelial cells is important in elucidating the pathogenesis of urinary tract infection. In this study, the African green monkey kidney ce...Studying the interaction between uropathogenic Escherichia coli (UPEC) and uroepithelial cells is important in elucidating the pathogenesis of urinary tract infection. In this study, the African green monkey kidney cells (Vero), human kidney carcinoma cells (Ketr-3) and bladder carcinoma cells (EJ) were infected by UPEC132, a clinical strain isolated from Tianjin, China, and were compared for their capacities to allow the adherence and invasion by this strain. The results revealed that all these cell lines could be attached and invaded by UPEC132. The adherence rates for Vero, Ketr-3 and EJ cells were (49.20 ± 7.55)%, (55.22 ± 4.09)% and (73.20 ± 5.26)%, respectively, and invasion frequencies were (2.61 ± 0.32)×10-3, (3.00 ± 0.34)×10-3 and (3.25 ± 0.20)×10-3, respectively. The statistical analysis showed that the adherence rate for EJ cells was significantly higher than those for the other two cell lines (P<0.05), and the invasion frequencies for EJ and Ketr-3 cells had no statistical differences (P>0.05) but were higher than that for Vero cells (P<0.05). Three cell lines were detected for the receptors for P pili of UPEC by using indirect immunofluorescence. The results showed that receptors existed on the surfaces of all cell lines, and the highest distribution was found on the surface of EJ cells. Additionally, the invasion of EJ cells by recombinant UPEC132/pSELECT-GFP could be directly visualized using confocal microscopy. These data strongly implicated that EJ cells could be more easily infected by UPEC132 than the other cells, and thus could serve as a good experimental target for further investigation of UPEC infection.展开更多
Uropathogenic Escherichia coli(UPEC) is the most common causative organism of human urinary tract infection(UTI).Several UPEC virulence factors have been identified,but more are yet to be found.We previously identifie...Uropathogenic Escherichia coli(UPEC) is the most common causative organism of human urinary tract infection(UTI).Several UPEC virulence factors have been identified,but more are yet to be found.We previously identified a novel 789-bp-long DNA fragment(named R049) in UPEC strain 132 using a suppressive subtractive hybridization technique.In the present study,we used genome walking to elongate the sequence of this fragment to obtain the whole gene sequence and examined the role of this gene product in generating protective immunity.Through bioinformatic analysis,we predicted that this gene is a 1311-bp open reading frame(ORF),which we designated ORFR049(GenBank accession No.:EF488001).We further constructed a prokaryotic expression system to express full recombinant R049 protein and isolated and purified the protein through IPTG induction and nickel affinity chromatography.Using mouse immunosera generated by the purified protein,we confirmed the natural expression and outer membrane localization of the protein in wild-type strain UPEC132 by Western blotting.To test the potential of this protein as a vaccine candidate,we immunized mice with the recombinant protein before challenging them with UPEC132 through the urinary tract.The results showed significantly reduced bacterial colonization in the urine and kidneys of the immunization group compared with the control group.However,the degree of renal pathological damage was not significantly improved in the immunized mice.Our study has identified a novel gene of UPEC which can generate protective immunity against UTI.This novel gene provides a promising new vaccine candidate.展开更多
文摘Uropathogenic Escherichia coli(UPEC)is the leading cause of urinary tract infections in women,causing significant morbidity and mortality in this population.Adherence to host epithelial cells is a pivotal step in the pathogenesis of UPEC.One of the most important virulence factors involved in mediating this attachment is the type 1 pilus(type 1 fimbria)encoded by a set of fim genes arranged in an operon.The expression of type 1 pili is controlled by a phenomenon known as phase variation,which reversibly switches between the expression of type 1 pili(Phase-ON)and loss of expression(Phase-OFF).Phase-ON cells have the promoter for the fimA structural gene on an invertible DNA element called fimS,which lines up to allow transcription,whereas transcription of the structural gene is silenced in Phase-OFF cells.The orientation of the fimS invertible element is controlled by two site-specific recombinases,FimB and FimE.Environmental conditions cause transcriptional and post-transcriptional changes in UPEC cells that affect the level of regulatory proteins,which in turn play vital roles in modulating this phase switching ability.The role of fim gene regulation in UPEC pathogenesis will be discussed.
文摘<span style="font-family:;" "=""><span style="font-family:Verdana;">The uropathogenic </span><i><span style="font-family:Verdana;">Staphylococcus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> is reported severally to be resistant to the drugs often used empirically for treatment of urinary tract infections (UTIs). Their ability to exhibit resistance to multiple drugs is a great de</span><span style="font-family:Verdana;">al of threat to successes recorded in the management of UTIs cause</span><span style="font-family:Verdana;">d by this pathogen. Lactic acid bacteria (LAB) have been demonstrated to exhibit an</span><span style="font-family:Verdana;">timicrobial activities but studies about their prospect against multi</span><span style="font-family:Verdana;">-drug resistant </span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> are quite few. This study therefore investigated acti</span><span><span style="font-family:Verdana;">vities of LAB against the multi-drug resistant </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> recover</span></span><span style="font-family:Verdana;">ed fro</span><span style="font-family:Verdana;">m urine samples of symptomatic women. The three differ</span><span style="font-family:Verdana;">ent species of LAB </span><span><span style="font-family:Verdana;">(</span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 62, </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> BTA 86 and </span><i><span style="font-family:Verdana;">Weis</span></i></span><i><span style="font-family:Verdana;">sella</span></i><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> BTA 40) previously isolated and identified by 16S rRNA s</span><span style="font-family:;" "=""><span style="font-family:Verdana;">e</span><span style="font-family:Verdana;">quencing were selected based on their history of antimicrobial activities. Their</span><span style="font-family:Verdana;"> m</span><span style="font-family:Verdana;">etabolites were employed in the antagonistic assays against six (6) mu</span><span style="font-family:Verdana;">lti-drug resista</span><span style="font-family:Verdana;">nt test pathogens recovered fro</span><span style="font-family:Verdana;">m urine samples of symptomatic, non-pregnant women attending clinics in Lagos, Nigeria and the control (</span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> subs bovis strain DSM 18669) following standard procedures. </span><span style="font-family:Verdana;">The pathogens showed resistances to almost all the antibiotics except</span><span style="font-family:Verdana;"> levofloxaci</span><span style="font-family:Verdana;">n, ciprofloxacin, imipenem while the control showed resistance to thr</span><span style="font-family:Verdana;">ee. The LAB, </span><i><span style="font-family:Verdana;">L.</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">fermentum</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> inhibited five (83.3%) of the pathogens with zone diameter of 12 - 17 mm, followed by </span><i><span style="font-family:Verdana;">W</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">confusa</span></i><span style="font-family:Verdana;"> inhibiting three (50%) with 15 - 17 mm. </span><i><span style="font-family:Verdana;">Lactobacillus</span></i></span><i><span style="font-family:;" "=""> </span></i><i><span style="font-family:Verdana;">johnsonii</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> on the other hand, inhibited a pathogen and the control with zones of 13 mm and 14 mm respectively. In conclusion, the extracted metabolites of LAB inhibited the growth of multi-drug resistant clinical isolates of uropathogenic </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">saprophyticus</span></i><span style="font-family:Verdana;"> and may therefore be potent alternatives to antibiotics.</span></span>
基金Partly supported by the research grant of Higher Education Commission Pakistan(No-3782)internal research funds of Qauid-i-Azam University Islamabad
文摘Objective:To scrutinize patterns of multi-drug-resistant uropathogenic Escherichia coli(UPEC) strains and particularly of fluoroquinolone-resistance this is an alternative choice for the treatment of urinary tract infections.Methods:Bacterial samples(n = 250) were collected from out-patients from August 2012 to August 2014 Islamabad.Antibiotic susceptibility profiling and determination of minimum inhibitory concentrations(MICs) and minimum bactericidal concentrations were performed according to the guidelines of Clinical and Laboratory Standards Institute(CLSI,2012).Genes,qnrA,qnrB and qnrS were identified by DNA amplification and sequencing.Results:The highest percentage of UPEC isolates were resistant to co-trimoxazole(82%) followed by cephalothin(80%),2nd Gen,3rd Gen and 4th Gen cephalosporins,respectively.Resistance against gentamicin,amikacin remained 29% and 4%.For other drugs including nitrofurantoin,tetracycline,carbapenem and beta-lactam inhibitors remained below 10%.Altogether,59% of the isolates were resistant to at least three antibiotics including one fluoroquinolone.Overall,MICs for ciprofloxacin remained(MIC≥256 μg/mL) and for levofloxacin(MIC≥16 μg/mL and 32 μg/mL).No significant differences were observed regarding MIC values of extended spectrumβ-lactamase(ESBL) and non-ESBL producers.For qnrS and qnrB positive isolates MICs remained above 32 μg/mL.Prevalence of UPEC was significantly higher among females and 40% of the isolates were ESBL producers.Conclusions:Higher percentages of ESBL producing UPEC were associated with urinary tract infections.Moreover,the majority of these isolates were multi-drug resistant and fluoroquinolone-resistant.
文摘Objective:In the present study we try to correlate between pathogenic intrinsic factor of Escherichia coli(E.coli) presented with different fimbria genotyes and biofilm formation with host immune factor entitled interleukin-6(IL-6) secretion as defense mechanism.Methods:A total of 91 pediatrics complaining of pyuria were included in the present study.In addition,20 healthy control children were included.Full microbiological study was performed for isolated E.coli.PapC alleles were studied by multiple alleles PCR and biofilm formation was studied.IL-6 was measured in urine.Results:IL-6 had statistically significant elevation in patients’urine compared to control.From biofilm study, it was found that 19 isolated E.coli had formed biofilm in vitro.Moreover,urine samples with positive biofilm formation of E.coli had statistically significant lower IL-6 secretion than those with negative E.coli for biofilms.The distribution of fimbria genotypes showed that the frequent genotype was for alleleⅠ(34.3%) followed by mixed allelesⅠandⅡ(24.1%).There was significant correlation between mixed alleles(Ⅰ&Ⅱ)and biofilm formation.Conclusion: The present study highlights the presence of significant strains of E.coli causing urinary tract infections capable of biofilm formation.Biofilm formation is associated with less innate immunity manifested by lower urinary IL- 6.The majority of isolates had fimbria genes.It appears that mixed allelesⅠandⅡhave prominent virulence effect with tendency for biofilm formation.
基金Supported by College of Medicine,Shaqra University,AlDwadmi,Kingdom of Saudi Arabia(Grant No.SG/RD/001/2014)
文摘Objective: To deal with the anti-uropathogenic and in silico screening of(E-)-N'-(substitutedbenzylidene)-2-(quinolin-8-yloxy)acetohydrazide analogues in order to search the potential anti-uropathogenic agents.Methods: Three(E-)-N'-(substituted-benzylidene)-2-(quinolin-8-yloxy)acetohydrazide analogues were synthesized. Structure elucidation was done using various spectroscopic techniques including infrared radiation, 1hydrogen-nuclear magnetic resonance, carbon-13 nuclear magnetic resonance, etc. Physicochemical score, bioactivity score and molecular docking studies were carried out using Lipinski's rule of five, Molinspiration(web based software), Autodock 4.2 tools. In vitro anti-uropathogenic activity was carried out against four pathogens named as Staphylococcus aureus(S. aureus), Staphylococcus epidermidis, Proteus mirabilis and Escherichia coli by disc diffusion method and macro-dilution test following their morphological and biochemical characterization.Results: The formation of(E-)-N'-(substituted-benz ylidene)-2-(quinolin-8-yloxy)acetohydrazide is confirmed from the spectroscopic results. All the compounds were found in compliance with Lipinski's rule of five and exhibited bioactivity score from-0.50 to 0.00. Docking results revealed that compound-1 is forming one hydrogen bond with TYR 576 and two hydrogen bond with GLU 569, while compound-2 is forming one hydrogen bond with ARG 599, and compound-3 forming 0 hydrogen bond. The anti-uropathogenic evaluation exhibited that compound one exhibited better activity against S. aureus, while it was found to possess moderate to good activity against both Gram-positive bacteria and Gram-negative bacteria excluding S. aureus.Conclusions: Our study revealed that compound one exhibited better activity than the standard in case of S. aureus and moderate to good activity against rest of the pathogens. Molecular docking, physicochemical and bioactivity studies strongly supported the experimental results. From the well obtained results it was concluded that compound-1 can lead as potential antiuropathogenic agents.
文摘As the lumen of the prostatic urethra becomes compromised by fibroadenomatous growth in the periurethral region of the prostate of men with Benign prostatic hyperplasia (BPH), urine outflow is obstructed progressively resulting in incomplete bladder empting causing stasis and may predispose patients to infection. Mid stream urine samples were collected from 94 BPH patients. Macroscopy, microscopy, culture and antibiotic susceptibility test were carried out on isolated uropathogens. Isolated bacteria were characterized using biochemical tests. Isolated bacterial pathogens include Proteus mirabilis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella oxytoca, Morgarella morgani, K. pneumonia and Enterococcus faecalis in order of frequency. The isolates show highest resistance of 87.1% to Ciprofloxacin and least resistance of 12.9% to Imipenem. The isolates were found to be multi-drug resistant and the 12.9% resistance to Imipenem suggests presence of Carbapenemase producing bacteria among the isolates.
文摘Urinary tract infections (UTI) are very common in all the developed as well as developing countries in which the majority of infections are catheter associated. Catheter associated urinary tract infections (CAUTI) is one of the major causes of hospital acquired infections. The aim of this study is to investigate influential demographic factors responsible for contamination associated with the rate of CAUTI, while taking into account type of urinary catheter used, the most common organisms found, patient diagnosis, age, gender, and comparison with other studies. During the study, 22 uropathogenic species were isolated from the different segments of urinary catheter samples of the patients collected from 12 different hospitals of Amravati city, Maharashtra, India from January 2015 to 2018. Gram negative organisms were the most frequent isolates, with <i>Pseudomonas aeruginosa</i> (16.08%) being the most common followed by <i>Escherichia coli</i> (10%) and <i>Candida albicans</i> accounted for almost 11% of all the uropathogens. It was found that the majority of uropathogens were isolated from the section A (Catheter segment inside the bladder) and section E (Catheter segment connected to drainage tube) of the urinary catheter. The duration of the catheterization plays the major role in the contamination and further infection to continue. It was observed that the female catheterized patients are more prone to the contamination and infection as compared to male catheterized patient. The antibiotic sensitivity pattern indicates that MAR (Multiple Antibiotic Resistance) index was more than 0.2 for almost all the uropathogens tested concluding that there is antibiotic stress on uropathogens and rate of resistance increased rapidly. Also it was found that there was a statistically significant association between the duration of catheterization, type of disease, age of patient and type of catheter with respect to gender.
文摘Background: Urinary tract infection (UTI) is a severe public health issue that affects a wide range of people around the world with Klebsiella pneumoniae accounting for up to 25% of all urinary tract infections. The higher rate of UTI associated with uropathogenic Klebsiella species has been associated with the emergence of hypervirulent and antibiotic-resistant strains facilitated by the misuse and overuse of antibiotics as well as other sociodemographic and behavioural practices of susceptible individuals. This study was aimed at investigating the prevalence and associated risk factors of uropathogenic Klebsiella species in Port Harcourt, Nigeria. Methodology: The study employed a descriptive cross-sectional study design comprising 300 subjects clinically suspected of having urinary tract infections attending the Rivers State University Medical Centre and the Rivers State University Teaching Hospital between March to August 2022. A standard urine culture procedure was used to ascertain significant bacteriuria after which Klebsiella colonies were isolated and identified using standard bacteriological techniques. The data generated from this study was represented as frequency and percentages, and inferential statistics were carried out using Chi-square with the aid of GraphPad Prism Software Version 9. Statistical significance was defined as a p-value of less than 0.05 at a 95% confidence interval. Result: The prevalence of uropathogenic Klebsiella sp. was 16%, with sex, pregnancy status, and religion of the individuals substantially linked (p p Klebsiella species. Conclusion: This study reports a relatively high prevalence of uropathogenic Klebsiella species at 16%, with the sex and pregnancy status of the subjects being significantly associated (p Klebsiella species in the current study. Health promotion and awareness efforts should be prioritised to inform susceptible demographics about their risks for urinary tract infections associated with uropathogenic Klebsiella species via targeted educational campaigns, collaboration with healthcare providers, use of social media and online platforms, workplace wellness programs, and community outreach programs amongst others. Antimicrobial susceptibility testing before prescriptions and treatment should be emphasized and upheld in all clinical settings.
文摘Haematuria is the presence of red blood cells in urine. It is most often caused by urinary tract infections of which Escherichia coli is frequently implicated. Impairment of kidney functions could occur as a result of infection or other complications of the kidney. The aim of the study was to determine the prevalence of uropathogenic Escherichia coli among adult male patients with haematuria and impaired kidneys attending a general hospital in Benue state. Three hundred and sixty-eight (368) samples of urine were collected from 368 male patients (≥ 40 years) attending the 23 general hospitals in Benue state. Each of the urine samples was divided into two parts for haematuria and isolation and identification of Escherichia coli. Blood samples (368) were also collected from the patients and used for quantitative determination of creatinine and estimation of glomerular filtration rate. The presence of haematuria was 45.1% and ranges from 12.5% to 100%. Prevalence of haematuria with respect to age shows that patients within the age group of 90 - 99 years had the highest rate (100%) and the least were those within the ages of 40 - 49 years (20.0%). Isolation rate of uropathogenic Escherichia coli was 16.3% and ranged from 6.3 to 37.5%. Patients within the age group of 90 - 99 years had the highest elevated impaired renal function of 4 (80%), followed by patients within the ages of 80 - 89 years [17 (77.3%)] and the lowest were those within the ages of 40 - 49 [6 (10.0%)]. The overall presence of haematuria in the patients was high (45.1%) with similar high Escherichia coli isolation rate and impaired renal function which could mean that acute or chronic kidney disease may set in.
文摘Urinary tract infections (UTIs) are common infections caused by normal skin or rectum bacteria that get into the urethra and infect the urinary tract. Although the infection can affect various parts of the tract, bladder infections are the most prevalent kind. Uropathogenic Escherichia Coli (UPEC) is the most common pathogen associated with UTI development. Therefore, inhibiting the UPEC protein target (PDB ID: 8BVD) appears to be a promising therapeutic strategy. Therefore, in this study, molecular docking and dynamics were conducted to examine the antibacterial activity of Aloe barbadensis miller against UPEC bacteria. The Aloe barbadensis miller natural compounds licochalcone A, palmidin B and palmidin C were downloaded from PubChem with amoxicillin, which was used as a control drug and studied against the target molecule. The potential parameters examined were the docking scores, absorption, distribution, metabolism, excretion, toxicity (ADMET), bioavailability, root mean square deviation (RMSD), root mean square fluctuation (RMSF), hydrogen bonding, radius of gyration, and potential energy of the system. Docking scores showed that all ligands demonstrated an admirable candidature as an inhibitor to 8BVD molecule, and the score hierarchy is licochalcone A (-6.4 kcal/mol), palmidin C (-6.1 kcal/mol), palmidin B (-6.0 kcal/mol), and amoxicillin (-5.9 kcal/mol). All ligands appeared to have good drug-like properties and oral bioavailability. Molecular dynamic studies showed that all ligands exhibited an excellent nominee as inhibitors in their vicinity at 20 ns. However, there is a relatively high fluctuation of palmidin B compared with other compounds, which seems to be more stable. This work suggests that the selected phytoconstituents could be used as inhibitors of the 8BVD protein in the fight against UTIs. However, further investigation on the clinical and experimental validation of UTI treatment’s specific mechanisms and effects is still welcomed.
文摘Urinary tract infection (UTI) is a frequent pathology among HTLV-I+ individuals being capable of severely compromising the kidneys and bladder. Molecular characteristics of uropathogenic Escherichia coli (UPEC) from HTLV-I+ infected individuals are unknown. UPEC isolates from HTVL-I+ individuals, with and without clinical symptoms of myelopathy, were submitted to genetic typing seeking to infer bacterial diversity and potential virulence. 71 bacterial isolates were characterized according to random amplified polymorphic DNA and phylotypes. Phylotyping classified E. coli into four phylogenetic groups: A (18.3%), B1 (16.9%), B2 (39.4%), and D (25.3%) and 8 phylotypes according to the presence of the genetic sequences chuA, yjaA and the DNA fragment TSPE4.C2: ﹣﹣﹣ (5.6%) and ﹣+﹣ (12.6%) in phylogroup A, ﹣﹣+ (7.0%) and ﹣++ (9.8%) in B1, +++ (32.3%) and ++﹣ (7.0%) in B2, +﹣﹣ (15.4%) and +﹣+ (9.8%) in D. The B2 phylogroup was the most prevalent among HTLV﹣ associated myelopathy and asymptomatic individuals. RAPD-PCR typing revealed a high degree of bacterial polymorphism indicating a non-clonal origin. Genotypes were not found to be distributed according to clinical status or epidemiological features. Our results lead us to suggest that the neurological impairment in HTLV-I+ individuals can be a risk factor for urinary infections due E. coli which are caused by distinct bacterial lineages.
基金This work was supported by the grants from the National Natural Science Foundation of China （30470096）.
文摘Human primary epithelial cells of renal pelvis was established to investigate the adherence of uropathogenic Escherichia coli （UPEC） to this cell line, in which the primary cell culture was performed by using cultivation of the normal epithelium of renal pelvis in keratinocyte serum free medium （K-SFM） with epidermal growth factor （EGF） and bovine pituitary extract （BPE）. Both UPEC132 obtained from urine specimen of patients with pyelonephritis and the pilus-free representative strain E. coli K-12p678- 54 were used to study the adherence of these strains on human primary epithelial cells of renal pelvis. The UPEC adherence was performed with observation on the morphological changes of the adhered cells, while the adhesion rates and indices were calculated in different times of experiment. In addition, the virulence genes hly and cnfl of UPEC132 were detected by multiplex PCR assay. In this study, the human primary epithelial cells of renal pelvis was found to exhibit the character of the transitional epithelial cells. Compared with the control group, the adhesion rates and indices began to increase from 15 min of the experiment time and reached its peak in 120 min. The adhesion rate and index of UPEC132 to human primary epithelial cells of renal pelvis were 74.4% and 34.0 respectively. Many microscopic changes in the primary cells adhered with UPEC132 could be detected, such as rounding or irregularity in shape, unevenness in staining and the cytoplasmic and nuclear changes. It suggests that human primary epithelial cells of renal pelvis can be used for the experiment on UPEC adhesion, thus providing a basis for the further study on the pathogenesis of UPEC.
基金Supported by the National Key Program for Infectious Diseases of China(Nos.2013ZX10004-203)National Natural Science Foundation of China(No.81401646)+1 种基金Chinese Academy of Traditional Chinese Medicine Joint Innovation Research Project(No.ZZ070808)Capital Featured Clinical Application and Product Promotion Project(No.Z151100004015132)
文摘Objectives： To investigate the resistance and virulence profiles of uropathogenic Escherichia coli（UPEC） and its treatment by Chinese medicine（CM） Fuzheng Qingre Lishi Formula（扶正清热利湿方, FQLF）. Methods： UPEC strains were isolated from recurrent urinary tract infections（UTIs） patients. Patient sensitivities to 17 antibiotics were tested by the disk diffusion method. Virulence genes were screened by plolymerase chain reaction. A mouse model was constructed using a multi-drug resistant and virulent UPEC strain and treated with FQLF or the antibiotic imipenem. The treatment efficacy was evaluated by bacterial clearance from urine and the urinary organs. Results： A total of 90 UPEC strains were collected, and 94.4% of the isolates were resistant to at least 1 antibiotic. Approximately 66.7% of the UPEC strains were multi-drug resistant. More than one virulence gene was found in 85.6% of the isolates. The extended-spectrum β-lactamases（ESBL）-positive strains were more resistant than the negative ones. The virulence gene number was positively correlated with the resistance number（P〈0.05）. A mouse model was successful y constructed using UPEC10. Treatment with either FQLF or antibiotics significantly cleared bacteria from the mouse urine after 14 days. In the untreated control, the bacteria lasted for 28 days. FQLF treatment of the UTI mouse model greatly reduced the bacterial number in the kidney and bladder, but could not completely clear the bacteria. Conclusions： Multi-drug resistance is common among UPEC isolates, and the resistance is positively related with virulence. FQLF could treat UPEC UTIs, but could not completely clear the bacteria from the host.
基金funded in part by University of Florida Research Foundation.TEM images were acquired by Nicole J.Machi and Rodolfo Alvarado in the Interdisciplinary Center for Biotechnology Research at University of Florida.
文摘Adhesion of P-type and type-1 fimbriated uropathogenic E.coli(UPEC)to uroepithelial cells initiates urinary tract infections(UTIs).This research aimed to evaluate the capacities of selected cranberry polyphenols and their microbial metabolites to inhibit such adhesion in vitro using a modified fluorometric method.Data showed that the inhibition capacity of myricetin increased with concentration and plateaued at 70%.It had IC50 values of 13.2μM against P-type E.coli and 5.50μM against type-1 E.coli.Quercetin showed similar anti-adhesion capacities to myricetin.Procyanidin A2 and B2 had weaker anti-adhesion activities than myricetin and quercetin,with maximal inhibition capacities of 20%-30%against UPEC.Hippuric acid,a major metabolite of cranberry polyphenols in human urine,showed a maximal inhibition of 20%at 558μM against type-1 E.coli adhesion,whereas no anti-adhesion activity against P-type E.coli was detected.The fractions of cranberry fruit powder enriched with proanthocyanidin polymers showed the highest anti-adhesion activities compared to the fractions enriched with anthocyanins,flavonols,or proanthocyanidin oligomers.Overall,the anti-adhesion activities of cranberry polyphenols and metabolites depend on their structures and the types of fimbriae on E.coli.
基金Supported by AJA University of Medical Sciences of Iran(Grant No.1649546/6743,2015).
文摘Objective:To determine the extended-spectrum beta-lactamase(ESBL)production and prevalence of bla_(CTX-M-1),bla_(SHV)and bla_(TEM)genes among uropathogenic Escherichia coli(UPEC)isolates from 3 military hospitals of Tehran during 2015-2016.Methods:One-hundred and eleven isolates were adopted.The antibiotic susceptibility testing was conducted according to Clinical and Laboratory Standards Institute guidelines.The combine disk was used for phenotypic ESBL production.The ceftazidime MIC was conducted with the micro-broth dilution test.The PCR assay was used to detect the bla_(CTX-M-1),bla_(SHV)and bla_(TEM)genes.Results:In the broth microdilution method,103(92.7%)isolates showed minimal inhibitory concentration(MIC)≥1μg/mL,and also in the combined disk method,89(80.1%of all)were ESBL positive.On the other hand,among 91 ceftazidime resistant isolates,86(77.4%of all)were ESBL positive.The difference between the two methods for ESBL confirmation was not significant.The result of MIC was similar to the disk diffusion method in the detection of phenotypic ESBL production.Among ESBL producer isolates,the prevalence of bla_(CTX-M-1),bla_(SHV)and bla_(TEM)was 77.4%(n=86),47.4%(n=53)and 2.4%(n=2),respectively.These genes were amplified in a wide range MIC of ceftazidime.Conclusions:The prevalence of multi-drug resistant UPEC and ESBL positive isolates was high in military hospitals.The majority of UPEC isolates amplified bla_(CTX-M-I)and bla_(SHV)typeβ-lactamase genes.One-third of isolates were positive in presence of both these genes.There was no relation between ceftazidime MIC and presence of beta-lactamase genes.
基金Supported by the National Natural Science Foundation of China (Grant No. 30470096)Specialized Research Fund for the Doctoral Program of Higher Education (Grant No. 20070062010)
文摘Studying the interaction between uropathogenic Escherichia coli (UPEC) and uroepithelial cells is important in elucidating the pathogenesis of urinary tract infection. In this study, the African green monkey kidney cells (Vero), human kidney carcinoma cells (Ketr-3) and bladder carcinoma cells (EJ) were infected by UPEC132, a clinical strain isolated from Tianjin, China, and were compared for their capacities to allow the adherence and invasion by this strain. The results revealed that all these cell lines could be attached and invaded by UPEC132. The adherence rates for Vero, Ketr-3 and EJ cells were (49.20 ± 7.55)%, (55.22 ± 4.09)% and (73.20 ± 5.26)%, respectively, and invasion frequencies were (2.61 ± 0.32)×10-3, (3.00 ± 0.34)×10-3 and (3.25 ± 0.20)×10-3, respectively. The statistical analysis showed that the adherence rate for EJ cells was significantly higher than those for the other two cell lines (P<0.05), and the invasion frequencies for EJ and Ketr-3 cells had no statistical differences (P>0.05) but were higher than that for Vero cells (P<0.05). Three cell lines were detected for the receptors for P pili of UPEC by using indirect immunofluorescence. The results showed that receptors existed on the surfaces of all cell lines, and the highest distribution was found on the surface of EJ cells. Additionally, the invasion of EJ cells by recombinant UPEC132/pSELECT-GFP could be directly visualized using confocal microscopy. These data strongly implicated that EJ cells could be more easily infected by UPEC132 than the other cells, and thus could serve as a good experimental target for further investigation of UPEC infection.
基金supported by the National Natural Science Foundation of China (30470096)the Specialized Research Fund for the Doctoral Program of Higher Education (20070062010)
文摘Uropathogenic Escherichia coli(UPEC) is the most common causative organism of human urinary tract infection(UTI).Several UPEC virulence factors have been identified,but more are yet to be found.We previously identified a novel 789-bp-long DNA fragment(named R049) in UPEC strain 132 using a suppressive subtractive hybridization technique.In the present study,we used genome walking to elongate the sequence of this fragment to obtain the whole gene sequence and examined the role of this gene product in generating protective immunity.Through bioinformatic analysis,we predicted that this gene is a 1311-bp open reading frame(ORF),which we designated ORFR049(GenBank accession No.:EF488001).We further constructed a prokaryotic expression system to express full recombinant R049 protein and isolated and purified the protein through IPTG induction and nickel affinity chromatography.Using mouse immunosera generated by the purified protein,we confirmed the natural expression and outer membrane localization of the protein in wild-type strain UPEC132 by Western blotting.To test the potential of this protein as a vaccine candidate,we immunized mice with the recombinant protein before challenging them with UPEC132 through the urinary tract.The results showed significantly reduced bacterial colonization in the urine and kidneys of the immunization group compared with the control group.However,the degree of renal pathological damage was not significantly improved in the immunized mice.Our study has identified a novel gene of UPEC which can generate protective immunity against UTI.This novel gene provides a promising new vaccine candidate.
