scholarly journals The Effect of Antimicrobial Drugs Tylocolinum, Tetragold and Cidisept-o on Escherichia coli Ultrastructure

2013 ◽  
Vol 2 (3) ◽  
pp. 65
Author(s):  
A. G. Shakhov ◽  
D. V. Fedosov ◽  
L. Y. Sashnina ◽  
O. V. Kazimirov
Keyword(s):  
Escherichia Coli ◽  
Bacterial Infections ◽  
Antimicrobial Agents ◽  
Water Solution ◽  
Uranyl Acetate ◽  
Chemotherapeutic Agents ◽  
Control Culture ◽  
New Drugs ◽  
Ultrastructural Changes ◽  
The Impact

<p>As a result of wide antibiotics, sulfonamides and other antimicrobial agents usage for the therapy of the animals with the bacterial infections caused by various causative agents including <em>Escherichia coli</em>, many microorganisms gained resistance to the chemotherapeutic agents. New combined drugs are being worked out during recent years, the components of which have various influence mechanisms on the bacterial cell that helps to provide resistance forming control. The results of the researches of the new antimicrobial agents, containing antibiotics in their composition, and non-antibiotic agent influence on the ultrastructure of <em>Escherichia coli</em> are represented in this study.</p> <p>5-hour <em>Escherichia coli 866</em> culture was processed by the drugs of the minimum bactericidal (Tylocolinum-0.39 µg/ml, Tetragold-6.25 µg/ml, Cidisept-o-25 µg/ml) and 4-time concentrations during 3 hours. Samples and control culture (without drugs) were fixed by the 2.5% glutaricdialdehyde on the s-Collidine Buffer, dehydrated in the ethanol with rising concentration, filled in epoxies. Ultrathin slices were stained by 2% water solution of uranyl acetate and lead citrate for 10 minutes. Then they were examined with the use of the electron microscope JEM-100 CX II by JEOL.</p> <p>The research showed deep ultrastructural changes in <em>Escherichia coli</em> cells under the antimicrobial agent influence determined by synergistic effect of combined Tylocolinum and Tetragold drugs components, possessing various bacteria influencing mechanisms, and aldehyde that is a component of Cidisept-o.</p> The electron microscopy usage allows to get unique information about the impact consequences of the traditional improved drugs and new drugs with antimicrobial activity on the bacterial infectious agents.

scholarly journals Investigation of the antimicrobial activity of danofoloxacin against bacteria pathogens in goats

2020 ◽  
Vol 22 (97) ◽  
pp. 74-78
Author(s):  
T. I. Stetsko ◽  
Ya. M. Liubenko ◽  
V. N. Padovskyi ◽  
L. L. Ostrovska ◽  
O. Yo. Kalinina ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Bacterial Infections ◽  
Chemotherapeutic Agents ◽  
Diffusion Method ◽  
Bacteriostatic Activity ◽  
Intestinal Infection ◽  
Sensitivity Testing ◽  
First Choice

Fluoroquinolones are critical antimicrobials for both human and veterinary medicine. Due to their unique mechanism of antimicrobial action and good pharmacokinetic properties, they are often the first choice drugs in the treatment of bacterial infections in animals. The purpose of the investigation was to study the antimicrobial activity of a third-generation fluoroquinolone antibiotic of danofloxacin against bacteria, pathogens of respiratory and intestinal infection in goats. The samples of the nasal outflows (respiratory infection) and fecal masses (intestinal infection) were collected from clinically ill goats for microbiological studies. The sensitivity test of the microflora of the biomaterial, carried out by the disco-diffusion method, showed that the microorganisms of all the samples were sensitive to danofloxacin. Bacteria Streptococcus pneumonia (n = 10), Staphylococcus aureus (n = 4) and Escherichia coli (n = 2) were isolated and identified from nasal exudate samples (n = 10). Pathogenic strains of Escherichia coli were isolated from all faecal samples (n = 12). The degree of bacteriostatic activity of danofloxacin was determined by establishing its minimum inhibitory concentration (MIC) for bacterial isolates by sequential dilutions in a liquid nutrient medium. The average MIC of danofloxacin for Streptococcus pneumoniae isolates was 0.26 ± 0.13 μg/ml and for Staphylococcus aureus isolates – 0.25 ± 0.075 μg/ml. For Escherichia coli strains isolated from faeces of goats suffering from coli infection, the average MIC of danofloxacin was 0.38 ± 0.12 μg/ml (range 0.2 to 0.8 μg/ml). Antimicrobial sensitivity testing have shown a high level of bacteriostatic activity of danofloxacin against bacteria, pathogens of respiratory and intestinal infections in goats. This may be the argument for the use of danofloxacin-based chemotherapeutic agents in the treatment of bacterial infections in goats, especially for the empirical approach to therapy.

scholarly journals Investigation of the Biochemical and Ultrastructural Mechanisms Underlying the Antimicrobial Activity of Mimusops spp. Extracts

2020 ◽  
Vol 17 (2) ◽  
pp. 0452
Author(s):  
Mahmoud S.M. Mohamed ◽  
Gehad Abdelmohsen ◽  
Gouda T. M. Dawoud
Keyword(s):  
Bacterial Infections ◽  
High Performance ◽  
Antimicrobial Agents ◽  
Antimicrobial Effect ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Ultrastructural Changes ◽  
Bacterial Strains ◽  
Leaf Extracts ◽  
Traditional Medicines

Antibiotic resistance is the major growing threat facing the pharmacological treatment of bacterial infections. Therefore, bioprospecting the medicinal plants could provide potential sources for antimicrobial agents. Mimusops, the biggest and widely distributed plant genus of family Sapotaceae, is used in traditional medicines due to its promising pharmacological activities. This study was conducted to elucidate the antimicrobial effect of three unexplored Mimusops spp. (M. kummel, M. laurifolia and M. zeyheri). Furthermore, the mechanisms underlying such antibacterial activity were studied. The Mimusops leaf extracts revealed significant antibacterial activities against the five tested bacterial strains with a maximum inhibition zone diameter of 22.0 mm against B. subtilis compared with standard antibiotic ciprofloxacin. The minimal inhibitory and bactericidal concentration values against tested Gram-positive and Gram-negative bacterial strains ranged from 3.15-12.5 µg/ml. However, weak antifungal effect was recorded against Candida albicans with MIC value ˃25 µg/ml. The 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay showed that M. caffra was the best antioxidant (IC50=14.75±0.028 µg/ml), while M. laurifolia was the least one (IC50=34.22±0.014 µg/ml). The phenolics in plant leaves extracts were identified and quantified by high performance liquid chromatography (HPLC) which revealed the presence of seven phenolic acids and four flavonoids. The abundant phenolic compounds were rutin (5.216±0.067 mg/g dried wt.) and gallic acid (0.296±0.068 mg/g) followed by myricetin (0.317±0.091 mg/g) then kaempferol (0.113±0.049 mg/g) as flavonoids. The antibacterial mechanism of M. laurifolia extract, as a representative species, induces ultrastructural changes in the model bacterium Staphylococcus aureus with cell wall and plasma membrane lysis as revealed by transmission electron microscopy. Overall, Mimusops species (M. laurifolia, M. kummel and M. zeyheri) are promising natural alternative sources for antimicrobial agents.

scholarly journals Conditional pathogenic microflora and its role in the eithiology of acute digestion disorders with features of diarrhea of newborned calves

2018 ◽  
Vol 20 (83) ◽  
pp. 304-307
Author(s):  
B.M. Kurtyak ◽  
M.S. Romanovych ◽  
T.O. Pundyak ◽  
L.V. Romanovych ◽  
G.V. Sobko ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Clostridium Perfringens ◽  
Chemotherapeutic Agents ◽  
New Drugs ◽  
Morphological Properties ◽  
Proteus Vulgaris ◽  
Mesenteric Lymph Nodes ◽  
Bacteriological Study ◽  
Digestive Disorders

The problem of treatment of acute digestive disorders with signs of diarrhea in calves remains relevant and important, as there are no sufficiently effective drugs, including antimicrobial effects. The low effectiveness of antibiotics and other chemotherapeutic agents and therapies in the vast majority of farms dictates the need to find new drugs. The purpose of our work was to study the significance of opportunistic microorganisms in the etiology of calving diarrhea. The research was conducted at farms of Lviv and Volyn regions. The incidence of newborn calves with acute digestive disorders with signs of diarrhea ranged from 36.8 to 100%, and mortality ranged from 17.4 to 30.8%. Bacteriological study was subjected to patmaterial from 20 dead calves at the age of 1–7 days. In this case, 88 cultures have been isolated from the internal organs, mesenteric lymph nodes, bone marrow, brain, walls and intestines. According to the culture – morphological properties, the cultures were classified into the following species: Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa, Diplococcus capsulatus, Clostridium perfringens. In the bacteriological study of all microorganisms isolated - Diplococcus capsulatus 29.5%, Escherichia coli 30.7%, Pseudomonas aeruginosa 19.3%, Clostridium perfringens 11.4%, Proteus vulgaris 9.1%. Out of the 14 households, the causes of the disease of calves with acute gastrointestinal disorders in 35.7% of cases were certain opportunistic pathogens (Escherichia coli, Diplococcus capsulatus, Pseudomonas aeruginosa, Clostridium perfringens, Proteus vulgaris). In most farms (64.28%), the disease was caused by association (2, 3 and more) types of microbes. The pathogenic properties of the isolated cultures were tested on white mice. In determining the pathogenicity of isolated cultures from dead calves on white mice, the most pathogenic were microorganisms of the species Pseudomonas aeruginosa. Experimental mice (42.0%) died within 6–12 hours after infection. Highly pathogenic were mixed cultures of E. coli, diplococci, Pseudomonas aeruginosa, which killed 58.0% of infected mice 24–48 hours after infection. This indicates an increase in the pathogenic properties of microorganisms in the association. In order not to allow the passage of conditionally pathogenic microflora, it is necessary to adhere to the sanitary regime in dispensaries and maternity departments, and the terms of disinfection with variable sectional retention.

scholarly journals Treatment of methicillin-resistant Staphylococcus aureus (MRSA): updated guidelines from the UK

2021 ◽  
Author(s):  
Nicholas M Brown ◽  
Erwin M Brown ◽  
Nicholas M Brown ◽  
Anna L Goodman ◽  
Carolyne Horner ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Antimicrobial Agents ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Superior Efficacy ◽  
Published Evidence ◽  
Impact On Treatment ◽  
The Uk ◽  
The Impact ◽  
New Evidence ◽  
Current Guidelines

Abstract The UK guidelines for the treatment of infections caused by MRSA have been updated and are published in JAC-Antimicrobial Resistance. The update reviews new evidence published since the previous UK guidelines were published over 10 years ago. It includes evidence relating to antimicrobial agents that have been licensed since then for the treatment of Gram-positive bacterial infections including MRSA. It also considers the impact on treatment of the changing epidemiology of MRSA in the UK, especially relating to circulating community strains. A striking finding from the current literature review was the paucity of good quality evidence. The current guidelines therefore represent a hybrid of varying degrees of evidence and expert opinion. Where there was no new published evidence, we have retained some of the existing recommendations. We were unable to find strong evidence of the superior efficacy of newer agents compared with that of vancomycin.

scholarly journals Bacteriophages: A Possible Solution to Combat Enteropathogenic Escherichia Coli ( EPEC) Infections in Neonatal goats

2021 ◽  
Author(s):  
Kanika Bhargava ◽  
K Gururaj ◽  
G. K. Aseri ◽  
Gopal Nath ◽  
Virendra Bahadur Yadav ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Bacterial Infections ◽  
Antimicrobial Agents ◽  
Developing Economies ◽  
Gastrointestinal Disease ◽  
Molecular Techniques ◽  
Economic Losses ◽  
Host Immune Responses ◽  
Phenotypic Tests

Abstract Due to the awareness and benefits of goat rearing in developing economies, goats' significance is increasing. Unfortunately, these ruminants are threatened via multiple bacterial pathogens such as enteropathogenic Escherichia coli (EPEC) and its pathotypes. In goat kids and lambs, EPEC causes gastrointestinal disease leading to substantial economic losses for farmers and may also pose a threat to public health via the spread of zoonotic diseases. Management of infection is primarily based on antibiotics, but the need for new therapeutic measures as an alternative to antibiotics is becoming vital because of the advent of antimicrobial resistance (AMR). The current study focuses on the prevalence of enteric diseases, their identification through various molecular techniques viz., SYBR green real-time PCR, conventional PCR based on bfpA gene, PCR based on uspA gene and isolation, purification of naturally occurring phages against three EPEC multi-drug resistant strains isolated from the neonatal goat. Bacteriophages are novel components that can be used to tackle bacterial infections and AMR, where host immune responses and antimicrobial agents become incompetent. It was observed that a PCR based approach is more effective and rapid as compared to phenotypic tests. It was also established that the isolated bacteriophages exhibited potent antibacterial efficacy in-vitro. Hence, bacteriophages, being a natural therapeutic biological agent docking bacterial host, may be explored as a potential alternative to antibiotics in managing public, livestock and environmental health in this troubling situation of AMR.

scholarly journals Antimicrobial Peptide MPX Against Escherichia Coli O157:H7 Infection and Inhibiting inflammation, Enhancing Epithelial Barrier and Promoting Nutrient Absorption in the Intestine

2020 ◽  
Author(s):  
Xue qin Zhao ◽  
Lei Wang ◽  
Chun ling Zhu ◽  
Xiao jing Xia ◽  
Shou ping Zhang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Peptide ◽  
Bacterial Infections ◽  
Intestinal Barrier ◽  
Animal Husbandry ◽  
New Drugs ◽  
Inflammatory Factors ◽  
Intestinal Diseases ◽  
E Coli ◽  
Tnf Α

Abstract Background: Escherichia coli can cause intestinal diseases in humans and livestock, destroy the intestinal barrier, exacerbate systemic inflammation, and seriously threaten human health and animal husbandry development. The antimicrobial peptide MPX is extracted from venom and possesses good antibacterial activity against gram-negative bacteria. The aim of this study was to investigate whether MPX could be effective against E. coli infection. Results: In this study, the CCK-8 and lactic dehydrogenase results showed that MPX exhibited no toxicity in IPEC-J2 cells even at a concentration of 128 µg/mL. Furthermore, MPX notably suppressed the levels of IL-2, IL-6, TNF-α, myeloperoxidase and LDH induced by E. coli and reduced inflammation by inhibiting the p-p38-, TLR4- and p-p65-dependent pathways. In addition, MPX improved the expression of ZO-1, occludin, and claudin and enhanced the wound healing ability of IPEC-J2 cells. The therapeutic effect of MPX was evaluated in a murine model, and the results showed that MPX could protect mice against lethal infection with E. coli, improve the survival rate of the mice, and reduce the colonization of E. coli in organs and feces. H&E staining showed that MPX increased the length of villi and reduced the infiltration of inflammatory cells into the jejunum, and the effect of MPX was better than that of enrofloxacin. The SEM and TEM results showed that MPX effectively ameliorated the damage caused by E. coli to the jejunum and increased the number and length of microvilli. In addition, real-time PCR revealed that MPX decreased the expression of IL-2, IL-6, and TNF-α in the jejunum and colon. Furthermore, immunohistochemistry and immunofluorescence studies revealed that MPX could reduce the expression of p-p38 and p-p65 in the jejunum, thereby reducing the secretion of inflammatory factors. Moreover, MPX increased the mRNA and protein expression of ZO-1, occludin and MUC2 in the jejunum and colon, improved the function of the intestinal barrier and promoted the absorption of nutrients. Conclusion: This study suggests that MPX may be an effective therapeutic agent against E. coli infection and other intestinal diseases, laying the foundation for the development of new drugs for bacterial infections.

scholarly journals Escherichia coli as Commensal and Pathogenic Bacteria among Food-Producing Animals: Health Implications of Extended Spectrum β-Lactamase (ESBL) Production

Animals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2239
Author(s):  
Sónia Ramos ◽  
Vanessa Silva ◽  
Maria de Lurdes Enes Dapkevicius ◽  
Manuela Caniça ◽  
María Teresa Tejedor-Junco ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Antimicrobial Agents ◽  
Severe Infection ◽  
Farm Animals ◽  
Neonatal Meningitis ◽  
Salmonella Spp ◽  
E Coli

Escherichia coli are facultative, anaerobic Gram-negative rods with many facets. Within resistant bacterial populations, they play an important ecological role and can be used as a bioindicator of antimicrobial resistance. All animal species used for food production, as well as humans, carry E. coli in their intestinal tracts; plus, the genetic flexibility and adaptability of this bacteria to constantly changing environments allows it to acquire a great number of antimicrobial resistance mechanisms. Thus, the prevalence of antimicrobial resistance in these commensal bacteria (or others, such as enterococci) can be a good indicator for the selective pressure caused by the use of antimicrobial agents, providing an early warning of the emergence of antimicrobial resistance in pathogens. As many as 90% of E. coli strains are commensals inhabiting the intestinal tracts of humans and warm-blooded animals. As a commensal, it lives in a mutually beneficial association with its hosts and rarely causes diseases. However, E. coli also remains as one of the most frequent causes of several common bacterial infections in humans and animals. In humans, it is the prominent cause of enteritis, community- and hospital-acquired urinary tract infection (UTI), septicemia, postsurgical peritonitis, and other clinical infections, such as neonatal meningitis, while, in farm animals, it is more prominently associated with diarrhea. On a global scale, E. coli can be considered the most important human pathogen, causing severe infection along with other major bacterial foodborne agents, such as Salmonella spp. and Campylobacter. Thus, the importance of resistance in E. coli, typically considered a benign commensal, should not be underestimated.

Efficacy of Antimicrobial Agents in Lettuce Leaf Processing Water for Control of Escherichia coli O157:H7

2009 ◽  
Vol 72 (7) ◽  
pp. 1392-1397 ◽  
Author(s):  
GUODONG ZHANG ◽  
LI MA ◽  
VANESSA H. PHELAN ◽  
MICHAEL P. DOYLE
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Agents ◽  
Fluorescent Protein ◽  
Organic Load ◽  
Escherichia Coli O157 ◽  
Peroxyacetic Acid ◽  
E Coli ◽  
Processing Water ◽  
Green Fluorescent ◽  
The Impact

The objectives of this research were to study transfer and control of Escherichia coli O157:H7 during simultaneous washing of inoculated and uninoculated lettuce pieces and to determine the efficacy of antimicrobial agents (peroxyacetic acid, mixed peracid, and sodium hypochlorite) on reducing the transfer of E. coli O157:H7 through processing water with or without organic load. Lettuce leaf pieces (5 by 5 cm) were inoculated with a five-strain mixture of green fluorescent protein–labeled E. coli O157:H7 at 5.6 log CFU per piece. One inoculated lettuce piece was added to five uninoculated leaves during washing. Peroxyacetic acid and mixed peracid were tested at 10, 20, and 30 ppm, and chlorine was tested at 30 and 50 ppm. No organic load (liquefied lettuce leaves) and 10% organic load in processing water were compared. Without organic load, peroxyacetic acid at 30 ppm, mixed peracid at 10, 20, and 30 ppm, and chlorine at 30 and 50 ppm all significantly reduced E. coli O157: H7 in processing water by 1.83, 1.73, 1.50, 1.83, 1.34, and 1.83 log CFU/ml, respectively, compared with washing with water alone. These antimicrobials at all concentrations tested also significantly reduced transfer of the bacteria from an inoculated leaf to uninoculated leaves in the processing water by 0.96 to 2.57 log CFU per piece. A 10% organic load in the processing water reduced efficacy of antimicrobial agents. In this contaminated water, peroxyacetic acid at 10 and 20 ppm and chlorine at 30 ppm produced effects not significantly different from those of water alone. Therefore, it is important to understand the impact of organic load when validating the effectiveness of antimicrobial treatments.

scholarly journals PhoU Is a Persistence Switch Involved in Persister Formation and Tolerance to Multiple Antibiotics and Stresses in Escherichia coli

2007 ◽  
Vol 51 (6) ◽  
pp. 2092-2099 ◽  
Author(s):  
Yongfang Li ◽  
Ying Zhang
Keyword(s):  
Escherichia Coli ◽  
Bacterial Infections ◽  
Environmental Changes ◽  
Great Majority ◽  
Negative Regulator ◽  
New Drugs ◽  
Effective Control ◽  
Diverse Range ◽  
Energy Inhibitors ◽  
Multiple Antibiotics

ABSTRACT When a bactericidal antibiotic is added to a growing bacterial culture, the great majority of the bacterial population is killed but a small number of metabolically quiescent bacteria called persisters survive antibiotic treatment. The mechanism of this bacterial persistence is poorly understood. In Escherichia coli, we identified a new persistence gene, phoU, whose inactivation leads to a generalized higher susceptibility than that of the parent strain to a diverse range of antibiotics, including ampicillin, norfloxacin, and gentamicin, and stresses, such as starvation, acid pH, heat, peroxide, weak acids, and energy inhibitors, especially in stationary phase. The PhoU mutant phenotype could be complemented by a functional phoU gene. Mutation in PhoU leads to a metabolically hyperactive status of the cell, as shown by an increased expression of energy production genes, flagella, and chemotaxis genes and a defect in persister formation. PhoU, whose expression is regulated by environmental changes like nutrient availability and age of culture, is a global negative regulator beyond its role in phosphate metabolism and facilitates persister formation by the suppression of many important cellular metabolic processes. A new model of persister formation based on PhoU as a persister switch is proposed. PhoU may be an ideal drug target for designing new drugs that kill persister bacteria for more effective control of bacterial infections.

scholarly journals Modelling the epidemiology of Escherichia coli ST131 and the impact of interventions on the community and healthcare centres

2016 ◽  
Vol 144 (9) ◽  
pp. 1974-1982 ◽  
Author(s):  
A. TALAMINOS ◽  
L. LÓPEZ-CERERO ◽  
J. CALVILLO ◽  
A. PASCUAL ◽  
L. M. ROA ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Agents ◽  
Current Knowledge ◽  
Epidemiological Studies ◽  
Term Care ◽  
E Coli ◽  
Care Facilities ◽  
Potential Impact ◽  
The Impact

SUMMARYST131 Escherichia coli is an emergent clonal group that has achieved successful worldwide spread through a combination of virulence and antimicrobial resistance. Our aim was to develop a mathematical model, based on current knowledge of the epidemiology of ESBL-producing and non-ESBL-producing ST131 E. coli, to provide a framework enabling a better understanding of its spread within the community, in hospitals and long-term care facilities, and the potential impact of specific interventions on the rates of infection. A model belonging to the SEIS (Susceptible–Exposed–Infected–Susceptible) class of compartmental models, with specific modifications, was developed. Quantification of the model is based on the law of mass preservation, which helps determine the relationships between flows of individuals and different compartments. Quantification is deterministic or probabilistic depending on subpopulation size. The assumptions for the model are based on several developed epidemiological studies. Based on the assumptions of the model, an intervention capable of sustaining a 25% reduction in person-to-person transmission shows a significant reduction in the rate of infections caused by ST131; the impact is higher for non-ESBL-producing ST131 isolates than for ESBL producers. On the other hand, an isolated intervention reducing exposure to antimicrobial agents has much more limited impact on the rate of ST131 infection. Our results suggest that interventions achieving a continuous reduction in the transmission of ST131 in households, nursing homes and hospitals offer the best chance of reducing the burden of the infections caused by these isolates.

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