scholarly journals Rapid and real-time monitoring of bacterial growth against antibiotics in solid growth medium using a contactless planar microwave resonator sensor

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mandeep Chhajer Jain ◽  
Anupama Vijaya Nadaraja ◽  
Rakesh Narang ◽  
Mohammad Hossein Zarifi
Keyword(s):  
Antibiotic Susceptibility ◽  
Split Ring Resonator ◽  
Great Promise ◽  
Clinical Settings ◽  
Microwave Resonator ◽  
Resonant Amplitude ◽  
E Coli ◽  
Non Invasive ◽  
Solid Agar ◽  
Detection Capabilities

AbstractInfection diagnosis and antibiotic susceptibility testing (AST) are pertinent clinical microbiology practices that are in dire need of improvement, due to the inadequacy of current standards in early detection of bacterial response to antibiotics and affordability of contemporarily used methods. This paper presents a novel way to conduct AST which hybridizes disk diffusion AST with microwave resonators for rapid, contactless, and non-invasive sensing and monitoring. In this research, the effect of antibiotic (erythromycin) concentrations on test bacterium, Escherichia coli (E. coli) cultured on solid agar medium (MH agar) are monitored through employing a microwave split-ring resonator. A one-port microwave resonator operating at a 1.76 GHz resonant frequency, featuring a 5 mm2 sensitive sensing region, was designed and optimized to perform this. Upon introducing uninhibited growth of the bacteria, the sensor measured 0.005 dB/hr, with a maximum change of 0.07 dB over the course of 15 hours. The amplitude change decreased to negligible values to signify inhibited growth of the bacteria at higher concentrations of antibiotics, such as a change of 0.005 dB in resonant amplitude variation while using 45 µg of antibiotic. Moreover, this sensor demonstrated decisive results of antibiotic susceptibility in under 6 hours and shows great promise to expand automation to the intricate AST workflow in clinical settings, while providing rapid, sensitive, and non-invasive detection capabilities.

scholarly journals Rapid Antibiotic Susceptibility Testing on Pathogenic Bacteria in Solid Growth Medium Using a Real-Time and Contactless Planar Microwave Resonator Sensor

2021 ◽  
Author(s):  
Mandeep Chhajer Jain ◽  
Anupama Pillai ◽  
Rakesh Narang ◽  
Mohammad Zarifi
Keyword(s):  
High Throughput ◽  
Antibiotic Susceptibility ◽  
Pathogenic Bacteria ◽  
Susceptibility Testing ◽  
Dielectric Materials ◽  
Great Promise ◽  
Microwave Resonator ◽  
Antibiotic Susceptibility Testing ◽  
Bacterial Strains ◽  
Non Invasive

Abstract Infection diagnosis and antibiotic susceptibility testing (AST) are pertinent clinical microbiology practices that are in dire need of improvement, as current standards are not able to keep up with the mutations and resistance development of certain bacterial strains. This paper presents a novel way to conduct AST which hybridizes disk diffusion AST with microwave resonators for rapid, contactless, non-invasive and high-throughput testing. This work uses Escherichia coli (E. coli) cultured on solid agar and places bacteria samples on a microwave split-ring resonator along with antibiotic disks (erythromycin) of various doses to demonstrate the viability of this sensing method in a clinical microbiological setting. The microwave resonator, operating at a 1.76 GHz resonant frequency, boasted a 5 mm2 sensitive sensing region. A one-port sensor was designed and optimized for detecting dielectric property variations of lossy dielectric materials accurately. This sensor was calibrated to detect uninhibited growth of the bacteria at 0.005 dB/hr, with a maximum change of 0.07 dB over the course of 15 hrs. The transient resonant amplitude change was subsequently dampened for each increasing dosage of antibiotic tested, with 45 µg of erythromycin showing negligible change indicating complete inhibited growth. This AST sensor demonstrated decisive results of antibiotic susceptibility in under 6 hours and shows great promise to further automate the intricate workflow of AST in clinical settings, while providing rapid, sensitive, non-invasive and high-throughput detection capabilities.

Differential Microwave Resonator Sensor Reveals Glucose-Dependent Growth Profile of E. coli on Solid Agar

2020 ◽  
Vol 30 (5) ◽  
pp. 531-534 ◽  
Author(s):  
Mandeep Chhajer Jain ◽  
Anupama Vijaya Nadaraja ◽  
Bianca Marjan Vizcaino ◽  
Deborah J. Roberts ◽  
Mohammad H. Zarifi
Keyword(s):  
Microwave Resonator ◽  
E Coli ◽  
Growth Profile ◽  
Solid Agar ◽  
Dependent Growth

scholarly journals Color-Coded Droplets and Microscopic Image Analysis for Multiplexed Antibiotic Susceptibility Testing

Biosensors ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 283
Author(s):  
Yunjin Jeong ◽  
Haewook Jang ◽  
Junwon Kang ◽  
Juhong Nam ◽  
Kyoungseob Shin ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Antibiotic Susceptibility ◽  
Drug Testing ◽  
Susceptibility Testing ◽  
Clinical Settings ◽  
Antibiotic Susceptibility Testing ◽  
Testing Conditions ◽  
Clinical Process ◽  
E Coli ◽  
Global Issue

Since the discovery of antibiotics, the emergence of antibiotic resistance has become a global issue that is threatening society. In the era of antibiotic resistance, finding the proper antibiotics through antibiotic susceptibility testing (AST) is crucial in clinical settings. However, the current clinical process of AST based on the broth microdilution test has limitations on scalability to expand the number of antibiotics that are tested with various concentrations. Here, we used color-coded droplets to expand the multiplexing of AST regarding the kind and concentration of antibiotics. Color type and density differentiate the kind of antibiotics and concentration, respectively. Microscopic images of a large view field contain numbers of droplets with different testing conditions. Image processing analysis detects each droplet, decodes color codes, and measures the bacterial growth in the droplet. Testing E. coli ATCC 25922 with ampicillin, gentamicin, and tetracycline shows that the system can provide a robust and scalable platform for multiplexed AST. Furthermore, the system can be applied to various drug testing systems, which require several different testing conditions.

The Order in Which Antibiotics are Administered Affects the Fitness Costs of Adherent-Invasive E. coli (AIEC) Strains

2019 ◽  
Author(s):  
Jordan B Gregg
Keyword(s):  
Crohn’S Disease ◽  
Crohn's Disease ◽  
Combination Therapy ◽  
Agar Plate ◽  
Sequential Therapy ◽  
Negative Control ◽  
Clinical Settings ◽  
Fitness Costs ◽  
Inflammatory Gene Expression ◽  
E Coli

AIEC-LF82 is a strain of bacteria that is surmised to have a role in causing IBD and Crohn’s disease by activating pro-inflammatory gene expression in organisms. Using antibiotics via combination therapy has been a technique used in clinical settings in an attempt to treat the strains, however, the attempts have not been that effective nor efficient in terms of completely halting the growth and colonization of AIEC to treat IBD and Crohn's disease patients. Research has shown that regarding hindering or preventing the colonization bacterial colonies, sequential therapy tends to be more effective and time-efficient than combination therapy, with fewer adverse effects. To test if this is also the case with the AIEC-LF82 strain of bacteria, I first tested AIEC’s response to combination therapy using the Penicillin-Streptomycin, Kanamycin-Chloramphenicol, antimicrobial peptide (AMP), Kanamycin, SPE phase and LB agar plates, all of which were experimental plates other than the LB agar plate that acted as the negative control. I then tested AIEC-LF82’s response to sequential therapy using the LB+ Kan + Spe, LB + AMP + Spe, LB+ Kan/Cam + Spe, LB + P/S + Spe, LB + P/S + Kan and LB + P/S + AMP and one LB agar plate acting as the negative control. The only differences between sets a and b were the order in which antibiotics were administered in the six aforementioned treatment sets. Ultimately, I found that set b of sequential therapy, strong-weak antibiotic treatments, was the most effective treatment but that set a regarding sequential therapy was actually the least effective of all of the treatments. In conclusion, using strong-weak sequential antibiotic therapy treatments appears to be a potentially promising option to treat patients suffering from Crohn's disease and IBD.

Antimicrobial Activity of Silver Nanoparticles Prepared Under an Ultrasonic Field

2011 ◽  
Vol 4 (3) ◽  
pp. 1491-1496
Author(s):  
Umadevi M ◽  
Rani T ◽  
Balakrishnan T ◽  
Ramanibai R
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Reduction Method ◽  
Therapeutic Potential ◽  
Chemical Reduction ◽  
Ultrasonic Field ◽  
Great Promise ◽  
Chemical Reduction Method ◽  
E Coli

Nanotechnology has great promise for improving the therapeutic potential of medicinal molecules and related agents. In this study, silver nanoparticles of different sizes were synthesized in an ultrasonic field using the chemical reduction method with sodium borohydride as a reducing agent. The size effect of silver nanoparticles on antimicrobial activity were tested against the microorganisms Staphylococcus aureus (MTCC No. 96), Bacillus subtilis (MTCC No. 441), Streptococcus mutans (MTCC No. 497), Escherichia coli (MTCC No. 739) and Pseudomonas aeruginosa (MTCC No. 1934). The results shows that B. subtilis, and E. coli were more sensitive to silver nanoparticles and its size, indicating the superior antimicrobial efficacy of silver nanoparticles. 

scholarly journals E. coli Enterotoxin LtB Enhances Vaccine-Induced Anti-H. pylori Protection by Promoting Leukocyte Migration into Gastric Mucus via Inflammatory Lesions

Cells ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 982
Author(s):  
Xiaoyan Peng ◽  
Rongguang Zhang ◽  
Chen Wang ◽  
Feiyan Yu ◽  
Mingyang Yu ◽  
...  
Keyword(s):  
Cellular Immunity ◽  
Protective Efficacy ◽  
Gastric Injury ◽  
Oral Vaccines ◽  
Gastric Mucus ◽  
E Coli ◽  
Non Invasive ◽  
Considerable Impact ◽  
H Pylori

Current studies indicate that the anti-H. pylori protective efficacy of oral vaccines to a large extent depends on using mucosal adjuvants like E. coli heat-lable enterotoxin B unit (LtB). However, the mechanism by which Th17/Th1-driven cellular immunity kills H. pylori and the role of LtB remains unclear. Here, two L. lactis strains, expressing H. pylori NapA and LtB, respectively, were orally administrated to mice. As observed, the administration of LtB significantly enhanced the fecal SIgA level and decreased gastric H. pylori colonization, but also markedly aggravated gastric inflammatory injury. Both NapA group and NapA+LtB group had elevated splenocyte production of IL-8, IL-10, IL-12, IL-17, IL-23 and INF-γ. Notably, gastric leukocytes’ migration or leakage into the mucus was observed more frequently in NapA+LtB group than in NapA group. This report is the first that discusses how LtB enhances vaccine-induced anti-H. pylori efficacy by aggravating gastric injury and leukocytes’ movement into the mucus layer. Significantly, it brings up a novel explanation for the mechanism underlying mucosal cellular immunity destroying the non-invasive pathogens. More importantly, the findings suggest the necessity to further evaluate LtB’s potential hazards to humans before extending its applications. Thus, this report can provide considerable impact on the fields of mucosal immunology and vaccinology.

scholarly journals Measurements Methods for the Development of MicroRNA-Based Tests for Cancer Diagnosis

2021 ◽  
Vol 22 (3) ◽  
pp. 1176
Author(s):  
Francesca Precazzini ◽  
Simone Detassis ◽  
Andrea Selenito Imperatori ◽  
Michela Alessandra Denti ◽  
Paola Campomenosi
Keyword(s):  
Expression Profiling ◽  
Clinical Stage ◽  
Response To Therapy ◽  
Clinical Settings ◽  
Molecular Tools ◽  
Altered Expression ◽  
Circulating Micrornas ◽  
Non Invasive ◽  
Mirna Expression Profiling ◽  
Technological Limitations

Studies investigating microRNAs as potential biomarkers for cancer, immune-related diseases, or cardiac pathogenic diseases, among others, have exponentially increased in the last years. In particular, altered expression of specific miRNAs correlates with the occurrence of several diseases, making these molecules potential molecular tools for non-invasive diagnosis, prognosis, and response to therapy. Nonetheless, microRNAs are not in clinical use yet, due to inconsistencies in the literature regarding the specific miRNAs identified as biomarkers for a specific disease, which in turn can be attributed to several reasons, including lack of assay standardization and reproducibility. Technological limitations in circulating microRNAs measurement have been, to date, the biggest challenge for using these molecules in clinical settings. In this review we will discuss pre-analytical, analytical, and post-analytical challenges to address the potential technical biases and patient-related parameters that can have an influence and should be improved to translate miRNA biomarkers to the clinical stage. Moreover, we will describe the currently available methods for circulating miRNA expression profiling and measurement, underlining their advantages and potential pitfalls.

scholarly journals Nitric oxide (NO) elicits aminoglycoside tolerance in Escherichia coli but antibiotic resistance gene carriage and NO sensitivity have not co-evolved

2021 ◽  
Author(s):  
Cláudia A. Ribeiro ◽  
Luke A. Rahman ◽  
Louis G. Holmes ◽  
Ayrianna M. Woody ◽  
Calum M. Webster ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Antibiotic Resistance ◽  
Antibiotic Susceptibility ◽  
Bacterial Pathogens ◽  
Antibiotic Resistance Gene ◽  
Antibiotic Resistance Genes ◽  
Resistance Mechanisms ◽  
Current Work ◽  
E Coli ◽  
Respiratory Inhibitor

AbstractThe spread of multidrug-resistance in Gram-negative bacterial pathogens presents a major clinical challenge, and new approaches are required to combat these organisms. Nitric oxide (NO) is a well-known antimicrobial that is produced by the immune system in response to infection, and numerous studies have demonstrated that NO is a respiratory inhibitor with both bacteriostatic and bactericidal properties. However, given that loss of aerobic respiratory complexes is known to diminish antibiotic efficacy, it was hypothesised that the potent respiratory inhibitor NO would elicit similar effects. Indeed, the current work demonstrates that pre-exposure to NO-releasers elicits a > tenfold increase in IC50 for gentamicin against pathogenic E. coli (i.e. a huge decrease in lethality). It was therefore hypothesised that hyper-sensitivity to NO may have arisen in bacterial pathogens and that this trait could promote the acquisition of antibiotic-resistance mechanisms through enabling cells to persist in the presence of toxic levels of antibiotic. To test this hypothesis, genomics and microbiological approaches were used to screen a collection of E. coli clinical isolates for antibiotic susceptibility and NO tolerance, although the data did not support a correlation between increased carriage of antibiotic resistance genes and NO tolerance. However, the current work has important implications for how antibiotic susceptibility might be measured in future (i.e. ± NO) and underlines the evolutionary advantage for bacterial pathogens to maintain tolerance to toxic levels of NO.

scholarly journals Antibiotic Susceptibility of Common Organisms Isolated from Urine Cultures of Nursing Home Residents

2020 ◽  
Vol 41 (S1) ◽  
pp. s118-s120
Author(s):  
Austin R. Penna ◽  
Taniece R. Eure Eure ◽  
Nimalie D. Stone ◽  
Grant Barney ◽  
Devra Barter ◽  
...  
Keyword(s):  
Nursing Home ◽  
Nursing Homes ◽  
Antibiotic Susceptibility ◽  
Clinical Decision Making ◽  
Service Providers ◽  
Urine Culture ◽  
Nursing Home Residents ◽  
Antibiotic Prescribing ◽  
E Coli ◽  
Susceptibility Data

Background: With the emergence of antibiotic resistant threats and the need for appropriate antibiotic use, laboratory microbiology information is important to guide clinical decision making in nursing homes, where access to such data can be limited. Susceptibility data are necessary to inform antibiotic selection and to monitor changes in resistance patterns over time. To contribute to existing data that describe antibiotic resistance among nursing home residents, we summarized antibiotic susceptibility data from organisms commonly isolated from urine cultures collected as part of the CDC multistate, Emerging Infections Program (EIP) nursing home prevalence survey. Methods: In 2017, urine culture and antibiotic susceptibility data for selected organisms were retrospectively collected from nursing home residents’ medical records by trained EIP staff. Urine culture results reported as negative (no growth) or contaminated were excluded. Susceptibility results were recorded as susceptible, non-susceptible (resistant or intermediate), or not tested. The pooled mean percentage tested and percentage non-susceptible were calculated for selected antibiotic agents and classes using available data. Susceptibility data were analyzed for organisms with ≥20 isolates. The definition for multidrug-resistance (MDR) was based on the CDC and European Centre for Disease Prevention and Control’s interim standard definitions. Data were analyzed using SAS v 9.4 software. Results: Among 161 participating nursing homes and 15,276 residents, 300 residents (2.0%) had documentation of a urine culture at the time of the survey, and 229 (76.3%) were positive. Escherichia coli, Proteus mirabilis, Klebsiella spp, and Enterococcus spp represented 73.0% of all urine isolates (N = 278). There were 215 (77.3%) isolates with reported susceptibility data (Fig. 1). Of these, data were analyzed for 187 (87.0%) (Fig. 2). All isolates tested for carbapenems were susceptible. Fluoroquinolone non-susceptibility was most prevalent among E. coli (42.9%) and P. mirabilis (55.9%). Among Klebsiella spp, the highest percentages of non-susceptibility were observed for extended-spectrum cephalosporins and folate pathway inhibitors (25.0% each). Glycopeptide non-susceptibility was 10.0% for Enterococcus spp. The percentage of isolates classified as MDR ranged from 10.1% for E. coli to 14.7% for P. mirabilis. Conclusions: Substantial levels of non-susceptibility were observed for nursing home residents’ urine isolates, with 10% to 56% reported as non-susceptible to the antibiotics assessed. Non-susceptibility was highest for fluoroquinolones, an antibiotic class commonly used in nursing homes, and ≥ 10% of selected isolates were MDR. Our findings reinforce the importance of nursing homes using susceptibility data from laboratory service providers to guide antibiotic prescribing and to monitor levels of resistance.Disclosures: NoneFunding: None

scholarly journals Cardiac Computed Tomography Radiomics for the Non-Invasive Assessment of Coronary Inflammation

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 879
Author(s):  
Kevin Cheng ◽  
Andrew Lin ◽  
Jeremy Yuvaraj ◽  
Stephen J. Nicholls ◽  
Dennis T.L. Wong
Keyword(s):  
Cardiac Computed Tomography ◽  
Quantitative Information ◽  
Imaging Biomarkers ◽  
Great Promise ◽  
Non Invasive ◽  
Quantitative Image ◽  
Artery Disease ◽  
Therapeutic Decision Making ◽  
Underlying Pathophysiology

Radiomics, via the extraction of quantitative information from conventional radiologic images, can identify imperceptible imaging biomarkers that can advance the characterization of coronary plaques and the surrounding adipose tissue. Such an approach can unravel the underlying pathophysiology of atherosclerosis which has the potential to aid diagnostic, prognostic and, therapeutic decision making. Several studies have demonstrated that radiomic analysis can characterize coronary atherosclerotic plaques with a level of accuracy comparable, if not superior, to current conventional qualitative and quantitative image analysis. While there are many milestones still to be reached before radiomics can be integrated into current clinical practice, such techniques hold great promise for improving the imaging phenotyping of coronary artery disease.

Sign in / Sign up

Export Citation Format

Share Document