The time course of calprotectin liberation from human neutrophil granulocytes after Escherichia coli and endotoxin challenge

Plasma calprotectin has previously been reported as a biomarker for sepsis. The aim of the present study was to elucidate the kinetics of calprotectin release from neutrophils exposed to Escherichia coli and endotoxin. Whole blood samples were exposed to E. coli bacteria or endotoxin in vitro. Blood samples were collected after 0, 1, 2, 3 and 4 h and plasma calprotectin was analysed by particle enhanced turbidimetric immunoassay while TNF-α, IL-6, neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) were analyzed by ELISA. When neutrophils were exposed to either E. coli or endotoxin, calprotectin levels began to increase within a couple of hours after the challenge. Calprotectin increases early in response to bacterial challenge. Given the logistic advantages of the calprotectin analysis, this may be of interest for early diagnosis of bacterial infections.

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STUDY ON BOVINE SUB-CLINICAL MASTITIS ON FARM CONDITION WITH SPECIAL EMPHASIS ON ANTIBIOGRAM OF THE CAUSATIVE BACTERIA

Bangladesh Journal of Veterinary Medicine ◽

10.3329/bjvm.v14i2.31386 ◽

2017 ◽

Vol 14 (2) ◽

pp. 161-166 ◽

Cited By ~ 1

Author(s):

M. T. Hasan ◽

M. R. Islam ◽

N. S. Runa ◽

M, N. Hasan ◽

A. H. M. M. Uddin ◽

...

Keyword(s):

Escherichia Coli ◽

Bacterial Infection ◽

Bacterial Infections ◽

Clinical Mastitis ◽

Economic Effects ◽

Single Infection ◽

Bacterial Isolates ◽

E Coli ◽

Staphylococcus Spp

The study was conducted to find out the prevalence of sub-clinical mastitis (SCM) and antibiogram of the causative bacteria in dairy cows at the Sylhet govt. Dairy Farm (SGDF) and Local Farms of Sylhet (LFS) during the period of July2014 to June2015. These farms were selected to assess the predominant types of bacteria involved in causing sub-clinical mastitis and to know the in vitro antibiotic sensitivity spectrum of these bacterial isolates against the commonly used antibiotics and to study the economic effects due to SCM. Use of California Mastitis Test (CMT) for the detection of sub-clinical mastitis showed 42out of 100 samples were test positive, among which +(Trace) 22.0%, ++(Distinct) 12.0%, +++(Strong) 3.0%, ±(Doubtful) 5.0%. Bacteriological examination of milk samples of 100 milch cows (400 quarters) revealed that 42 cows (42.0%) had suffering from SCM with different bacterial infection with 95% confidence limit was 32.1574-51.8426. Among 42 positive samples31 (31.0%) cows had mono-bacterial infection and 11 (11.0%) cows had mixed bacterial infections. Statistical analysis of the result of single and mixed bacterial infections in the milk of apparently healthy milch cows revealed that the single infection was significantly (P < 0.05) higher than mixed bacterial infection. Of the 31 mono-bacterial isolates, of which 23 (23.0%) isolates were Staphylococci, 3 (3.0%) isolates were Escherichia coli, 5 (5.0%) isolated Streptococcus spp. The 11 cows had mixed infection, of which 5 had Staphylococcus spp. + Streptococcus spp., 3 had E. coli + Staphylococcus spp., and 3 had Streptococcus spp. + E. coli. Of 42 positive cases of SCM Staphylococcus spp. isolated from 23 samples. Among these 23 positive samples 13 obtained from SGDF (37.14%) and 10 obtained from LFS (15.38%). Escherichia coli isolated from 3 samples. Among these 3 positive samples 3 obtained from LFS (4.62%). Streptococcus spp. isolated from 5 samples. Among these 5 positive samples 1 obtained from SGDF (2.86%) and 4 obtained from LFS (6.15%). Ceftriaxone, ciprofloxacin and gentamicin were the best drug for treating sub-clinical mastitis.

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Role of Shiga Toxins in Cytotoxicity and Immunomodulatory Effects of Escherichia coli O157:H7 during Host-Bacterial Interactions in vitro

Toxins ◽

10.3390/toxins12010048 ◽

2020 ◽

Vol 12 (1) ◽

pp. 48 ◽

Cited By ~ 1

Author(s):

Bruballa ◽

Shiromizu ◽

Bernal ◽

Pineda ◽

Sabbione ◽

...

Keyword(s):

Escherichia Coli ◽

Time Course ◽

Cell Damage ◽

Enterohemorrhagic Escherichia Coli ◽

Host Cells ◽

Epithelial Cell Line ◽

Bacterial Survival ◽

E Coli ◽

Clinical Conditions

Enterohemorrhagic Escherichia coli (EHEC) strains are food-borne pathogens that can cause different clinical conditions. Shiga toxin 2a and/or 2c (Stx2)-producing E. coli O157:H7 is the serotype most frequently associated with severe human disease. In this work we analyzed the hypothesis that host cells participate in Stx2 production, cell damage, and inflammation during EHEC infection. With this aim, macrophage-differentiated THP-1 cells and the intestinal epithelial cell line HCT-8 were incubated with E. coli O157:H7. A time course analysis of cellular and bacterial survival, Stx2 production, stx2 transcription, and cytokine secretion were analyzed in both human cell lines. We demonstrated that macrophages are able to internalize and kill EHEC. Simultaneously, Stx2 produced by internalized bacteria played a major role in macrophage death. In contrast, HCT-8 cells were completely resistant to EHEC infection. Besides, macrophages and HCT-8 infected cells produce IL-1β and IL-8 inflammatory cytokines, respectively. At the same time, bacterial stx2-specific transcripts were detected only in macrophages after EHEC infection. The interplay between bacteria and host cells led to Stx production, triggering of inflammatory response and cell damage, all of which could contribute to a severe outcome after EHEC infections.

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Mutant Prevention Concentration Siprofloksasin Terhadap Escherichia coli Patogen dari Kloaka Broiler Secara In Vitro

Jurnal Sain Veteriner ◽

10.22146/jsv.57040 ◽

2021 ◽

Vol 39 (1) ◽

pp. 20

Author(s):

Maria Fatima Palupi ◽

Eli Nugraha ◽

Meutia Hayati ◽

Neneng Atikah

Keyword(s):

Escherichia Coli ◽

Bacterial Infections ◽

Single Step ◽

In Vitro Test ◽

Mutant Selection ◽

E Coli ◽

Wide Range ◽

Mutant Prevention Concentration ◽

Production Animals

Mutant prevention concentration (MPC) is an in vitro test used to determine the lowest drug concentration needed to inhibit the growth of a single-step-mutant bacterial subpopulation. The purpose of this study was to determine the MPC value of ciprofloxacin against pathogenic Escherichia coli to obtained the range of mutant selection windows (MSW) of ciprofloxacin. Ciprofloxacin is a quinolone group that is included in the Highest Priority Critically Important Antimicrobials for Human Medicine but is also used for the treatment of bacterial infections in production animals. Twenty-four of pathogenic E. coli isolates sensitive to ciprofloxacin were tested to obtain MPC values and minimum inhibitory concentration (MIC) values. Test the MPC and MIC values to get the MSW range is done by the method of agar dilution. Mueller-Hinton agar containing standard ciprofloxacin was inoculated with 1010 cfu E. coli for the MPC test and 104 for the MIC test. Based on the MPC test results, the MPC value of ciprofloxacin was 4-64 μg / mL (22.96 ± 19.07 μg / mL) and there was one isolate which had an MPC> 256 μg / mL. These results give a wide range of MSW with a lower limit of the MIC value of 0.25 - 2 µg / mL (0.55 ± 0.37 µg / mL) to the upper limit of the MPC value of 4-64 µg / mL (22.96 ± 19.07 μg / mL). Based on the results of this MPC assessment it can be concluded that the dose of ciprofloxacin in production animals has a wide range of MSW that is allow for single-step mutants.

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Escherichia coli Nissle 1917 Targets and Restrains Mouse B16 Melanoma and 4T1 Breast Tumors through Expression of Azurin Protein

Applied and Environmental Microbiology ◽

10.1128/aem.01390-12 ◽

2012 ◽

Vol 78 (21) ◽

pp. 7603-7610 ◽

Cited By ~ 41

Author(s):

Yunlei Zhang ◽

Youming Zhang ◽

Liqiu Xia ◽

Xiangli Zhang ◽

Xuezhi Ding ◽

...

Keyword(s):

Escherichia Coli ◽

Bacterial Infections ◽

Inflammatory Responses ◽

Breast Tumors ◽

B16 Melanoma ◽

Content Type ◽

E Coli ◽

Immunocompetent Mice

ABSTRACTMany studies have demonstrated that intravenously administered bacteria can target and proliferate in solid tumors and then quickly be released from other organs. Here, we employed the tumor-targeting property ofEscherichia coliNissle 1917 to inhibit mouse B16 melanoma and 4T1 breast tumors through the expression of azurin protein. For this purpose, recombinant azurin-expressingE. coliNissle 1917 was developed. The levels ofin vitroandin vivoazurin secretion in the engineered bacterium were determined by immunochemistry. Our results demonstrated that B16 melanoma and orthotopic 4T1 breast tumor growth were remarkably restrained and pulmonary metastasis was prevented in immunocompetent mice. It is worth noting that this therapeutic effect partially resulted from the antitumor activity of neutrophils and lymphocytes due to inflammatory responses caused by bacterial infections. No toxicity was observed in the animal during the experiments. This study indicates thatE. coliNissle 1917 could be a potential carrier to deliver antitumor drugs effectively for cancer therapy.

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In Vitro Evaluation of a Phage Cocktail Controlling Infections with Escherichia coli

Viruses ◽

10.3390/v12121470 ◽

2020 ◽

Vol 12 (12) ◽

pp. 1470

Author(s):

Imke H. E. Korf ◽

Sophie Kittler ◽

Anna Bierbrodt ◽

Ruth Mengden ◽

Christine Rohde ◽

...

Keyword(s):

Escherichia Coli ◽

Bacterial Infections ◽

Animal Health ◽

High Specificity ◽

Resistant Mutant ◽

Resistant Bacteria ◽

Bacterial Cells ◽

E Coli ◽

Phage Cocktail

Worldwide, poultry industry suffers from infections caused by avian pathogenic Escherichia coli. Therapeutic failure due to resistant bacteria is of increasing concern and poses a threat to human and animal health. This causes a high demand to find alternatives to fight bacterial infections in animal farming. Bacteriophages are being especially considered for the control of multi-drug resistant bacteria due to their high specificity and lack of serious side effects. Therefore, the study aimed on characterizing phages and composing a phage cocktail suitable for the prevention of infections with E. coli. Six phages were isolated or selected from our collections and characterized individually and in combination with regard to host range, stability, reproduction, and efficacy in vitro. The cocktail consisting of six phages was able to inhibit formation of biofilms by some E. coli strains but not by all. Phage-resistant variants arose when bacterial cells were challenged with a single phage but not when challenged by a combination of four or six phages. Resistant variants arising showed changes in carbon metabolism and/or motility. Genomic comparison of wild type and phage-resistant mutant E28.G28R3 revealed a deletion of several genes putatively involved in phage adsorption and infection.

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Substituted 4-Formyl-2H-chromen-2-ones: Their Reaction with N-(2,3,4,6-Tetra-Oacetyl- β-D-galactopyranosyl)thiosemicarbazide, Antibacterial and Antifungal Activity of Their Thiosemicarbazone Products

Current Organic Chemistry ◽

10.2174/1385272824999200812132256 ◽

2020 ◽

Vol 24 (19) ◽

pp. 2272-2282

Author(s):

Vu Ngoc Toan ◽

Nguyen Minh Tri ◽

Nguyen Dinh Thanh

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Candida Albicans ◽

Selenium Dioxide ◽

Antibacterial And Antifungal Activity ◽

E Coli ◽

Antibacterial And Antifungal Activities ◽

Alkyl Ethers ◽

Antibacterial And Antifungal

Several 6- and 7-alkoxy-2-oxo-2H-chromene-4-carbaldehydes were prepared from corresponding alkyl ethers of 6- and 7-hydroxy-4-methyl-2-oxo-2H-chromen-2-ones by oxidation using selenium dioxide. 6- and 7-Alkoxy-4-methyl-2H-chromenes were obtained with yields of 57-85%. Corresponding 4-carbaldehyde derivatives were prepared with yields of 41-67%. Thiosemicarbazones of these aldehydes with D-galactose moiety were synthesized by reaction of these aldehydes with N-(2,3,4,6-tetra-O-acetyl-β-Dgalactopyranosyl) thiosemicarbazide with yields of 62-74%. These thiosemicarbazones were screened for their antibacterial and antifungal activities in vitro against bacteria, such as Staphylococcus aureus, Escherichia coli, and fungi, such as Aspergillus niger, Candida albicans. Several compounds exhibited strong inhibitory activity with MIC values of 0.78- 1.56 μM, including 8a (against S. aureus, E. coli, and C. albicans), 8d (against E. coli and A. niger), 9a (against S. aureus), and 9c (against S. aureus and C. albicans).

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Combination therapy of cisplatin with cilastatin enables an increased dose of cisplatin, enhancing its antitumor effect by suppression of nephrotoxicity

Scientific Reports ◽

10.1038/s41598-020-80853-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Masashi Arita ◽

Satoshi Watanabe ◽

Nobumasa Aoki ◽

Shoji Kuwahara ◽

Ryo Suzuki ◽

...

Keyword(s):

Anticancer Agents ◽

Cell Injury ◽

Kidney Injury ◽

Antitumor Effects ◽

Cisplatin Nephrotoxicity ◽

Proximal Tubular ◽

Nephrotoxic Drugs ◽

Kidney Injury Molecule 1 ◽

Dose Dependent

AbstractCisplatin, one of the most active anticancer agents, is widely used in standard chemotherapy for various cancers. Cisplatin is more poorly tolerated than other chemotherapeutic drugs, and the main dose-limiting toxicity of cisplatin is its nephrotoxicity, which is dose-dependent. Although less toxic methods of cisplatin administration have been established, cisplatin-induced nephrotoxicity remains an unsolved problem. Megalin is an endocytic receptor expressed at the apical membrane of proximal tubules. We previously demonstrated that nephrotoxic drugs, including cisplatin, are reabsorbed through megalin and cause proximal tubular cell injury. We further found that cilastatin blocked the binding of cisplatin to megalin in vitro. In this study, we investigated whether cilastatin could reduce cisplatin-induced nephrotoxicity without influencing the antitumor effects of cisplatin. Nephrotoxicity was decreased or absent in mice treated with cisplatin and cilastatin, as determined by kidney injury molecule-1 staining and the blood urea nitrogen content. Combined with cilastatin, a twofold dose of cisplatin was used to successfully treat the mice, which enhanced the antitumor effects of cisplatin but reduced its nephrotoxicity. These findings suggest that we can increase the dose of cisplatin when combined with cilastatin and improve the outcome of cancer patients.

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Three-Year Trend in Escherichia coli Antimicrobial Resistance among Children’s Urine Cultures in an Italian Metropolitan Area

Children ◽

10.3390/children8070597 ◽

2021 ◽

Vol 8 (7) ◽

pp. 597

Author(s):

Luca Pierantoni ◽

Laura Andreozzi ◽

Simone Ambretti ◽

Arianna Dondi ◽

Carlotta Biagi ◽

...

Keyword(s):

Escherichia Coli ◽

Metropolitan Area ◽

Bacterial Infections ◽

Asymptomatic Bacteriuria ◽

Multidrug Resistant ◽

Resistance Rate ◽

First Line ◽

E Coli ◽

First Line Therapy ◽

Tract Infections

Urinary tract infections (UTIs) are among the most common bacterial infections in children, and Escherichia coli is the main pathogen responsible. Several guidelines, including the recently updated Italian guidelines, recommend amoxicillin-clavulanic acid (AMC) as a first-line antibiotic therapy in children with febrile UTIs. Given the current increasing rates of antibiotic resistance worldwide, this study aimed to investigate the three-year trend in the resistance rate of E. coli isolated from pediatric urine cultures (UCs) in a metropolitan area of northern Italy. We conducted a retrospective review of E. coli-positive, non-repetitive UCs collected in children aged from 1 month to 14 years, regardless of a diagnosis of UTI, catheter colonization, urine contamination, or asymptomatic bacteriuria. During the study period, the rate of resistance to AMC significantly increased from 17.6% to 40.2% (p < 0.001). Ciprofloxacin doubled its resistance rate from 9.1% to 16.3% (p = 0.007). The prevalence of multidrug-resistant E. coli rose from 3.9% to 9.2% (p = 0.015). The rate of resistance to other considered antibiotics remained stable, as did the prevalence of extended spectrum beta-lactamases and extensively resistant E. coli among isolates. These findings call into question the use of AMC as a first-line therapy for pediatric UTIs in our population, despite the indications of recent Italian guidelines.

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In vitro activity of antimicrobial peptide CDP-B11 alone and in combination with colistin against colistin-resistant and multidrug-resistant Escherichia coli

Scientific Reports ◽

10.1038/s41598-021-81140-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kaitlin S. Witherell ◽

Jason Price ◽

Ashok D. Bandaranayake ◽

James Olson ◽

Douglas R. Call

Keyword(s):

Escherichia Coli ◽

Antimicrobial Peptide ◽

Membrane Integrity ◽

Antibiotic Resistance Genes ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Multidrug Resistant Bacteria ◽

E Coli ◽

Minimal Media

AbstractMultidrug-resistant bacteria are a growing global concern, and with increasingly prevalent resistance to last line antibiotics such as colistin, it is imperative that alternative treatment options are identified. Herein we investigated the mechanism of action of a novel antimicrobial peptide (CDP-B11) and its effectiveness against multidrug-resistant bacteria including Escherichia coli #0346, which harbors multiple antibiotic-resistance genes, including mobilized colistin resistance gene (mcr-1). Bacterial membrane potential and membrane integrity assays, measured by flow cytometry, were used to test membrane disruption. Bacterial growth inhibition assays and time to kill assays measured the effectiveness of CDP-B11 alone and in combination with colistin against E. coli #0346 and other bacteria. Hemolysis assays were used to quantify the hemolytic effects of CDP-B11 alone and in combination with colistin. Findings show CDP-B11 disrupts the outer membrane of E. coli #0346. CDP-B11 with colistin inhibits the growth of E. coli #0346 at ≥ 10× lower colistin concentrations compared to colistin alone in Mueller–Hinton media and M9 media. Growth is significantly inhibited in other clinically relevant strains, such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae. In rich media and minimal media, the drug combination kills bacteria at a lower colistin concentration (1.25 μg/mL) compared to colistin alone (2.5 μg/mL). In minimal media, the combination is bactericidal with killing accelerated by up to 2 h compared to colistin alone. Importantly, no significant red blood hemolysis is evident for CDP-B11 alone or in combination with colistin. The characteristics of CDP-B11 presented here indicate that it can be used as a potential monotherapy or as combination therapy with colistin for the treatment of multidrug-resistant infections, including colistin-resistant infections.

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Mechanistic insights into synergy between nalidixic acid and tetracycline against clinical isolates of Acinetobacter baumannii and Escherichia coli

Communications Biology ◽

10.1038/s42003-021-02074-5 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Amit Gaurav ◽

Varsha Gupta ◽

Sandeep K. Shrivastava ◽

Ranjana Pathania

Keyword(s):

Escherichia Coli ◽

Acinetobacter Baumannii ◽

Nalidixic Acid ◽

Bacterial Infections ◽

Clinical Isolates ◽

Hospital Environment ◽

Infection Model ◽

Drug Resistant ◽

E Coli

AbstractThe increasing prevalence of antimicrobial resistance has become a global health problem. Acinetobacter baumannii is an important nosocomial pathogen due to its capacity to persist in the hospital environment. It has a high mortality rate and few treatment options. Antibiotic combinations can help to fight multi-drug resistant (MDR) bacterial infections, but they are rarely used in the clinics and mostly unexplored. The interaction between bacteriostatic and bactericidal antibiotics are mostly reported as antagonism based on the results obtained in the susceptible model laboratory strain Escherichia coli. However, in the present study, we report a synergistic interaction between nalidixic acid and tetracycline against clinical multi-drug resistant A. baumannii and E. coli. Here we provide mechanistic insight into this dichotomy. The synergistic combination was studied by checkerboard assay and time-kill curve analysis. We also elucidate the mechanism behind this synergy using several techniques such as fluorescence spectroscopy, flow cytometry, fluorescence microscopy, morphometric analysis, and real-time polymerase chain reaction. Nalidixic acid and tetracycline combination displayed synergy against most of the MDR clinical isolates of A. baumannii and E. coli but not against susceptible isolates. Finally, we demonstrate that this combination is also effective in vivo in an A. baumannii/Caenorhabditis elegans infection model (p < 0.001)

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