Solvent exchange-induced in situ forming gel comprising ethyl cellulose-antimicrobial drugs.

Science.gov (United States)

Phaechamud, Thawatchai; Mahadlek, Jongjan

2015-10-15

Solvent-exchanged in situ forming gel is a drug delivery system which is in sol form before administration. When it contacts with the body fluid, then the water miscible organic solvent dissipates and water penetrates into the system, leading the polymer precipitation as in situ gel at the site of injection. The aim of this research was to study the parameters affecting the gel properties, drug release and antimicrobial activities of the in situ forming gels prepared from ethyl cellulose (EC) dissolved in N-methyl pyrrolidone (NMP) to deliver the antimicrobial agents (doxycycline hyclate, metronidazole and benzyl peroxide) for periodontitis treatment. The gel appearance, pH, viscosity, rheology, syringeability, gel formation, rate of water diffusion into the gels, in vitro degradation, drug release behavior and antimicrobial activities against Staphylococcus aureus, Escherichia coli, Candida albicans, Streptococcus mutans and Porphyrommonas gingivalis were determined. Increasing the amount of EC increased the viscosity of system while still exhibiting Newtonian flow and increased the work of syringeability whereas decreased the releasing of drug. The system transformed into the rigid gel formation after being injected into the simulated gingival crevicular fluid. The developed systems containing 5% w/w antimicrobial agent showed the antimicrobial activities against all test bacteria. Thus the developed solvent exchange-induced in situ forming gels comprising EC-antimicrobial drugs exhibited potential use for periodontitis treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

Antimicrobial drug use in hospitalized children

NARCIS (Netherlands)

Liem, T.B.Y.

2011-01-01

The discovery of antibiotics represents one of the milestones in modern medicine and has since the beginning of the 20th century made a major contribution to the reduction in mortality and morbidity from infectious diseases. The shadow side of their success is antimicrobial drug resistance which is

Intraperiodontal pocket: An ideal route for local antimicrobial drug delivery

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Sreeja C Nair

2012-01-01

Full Text Available Periodontal pockets act as a natural reservoir filled with gingival crevicular fluid for the controlled release delivery of antimicrobials directly. This article reflects the present status of nonsurgical controlled local intrapocket delivery of antimicrobials in the treatment of periodontitis. These sites have specialty in terms of anatomy, permeability, and their ability to retain a delivery system for a desired length of time. A number of antimicrobial products and the composition of the delivery systems, its use, clinical results, and their release are summarized. The goal in using an intrapocket device for the delivery of an antimicrobial agent is the achievement and maintenance of therapeutic drug concentration for the desired period of time. Novel controlled drug delivery system are capable of improving patient compliance as well as therapeutic efficacy with precise control of the rate by which a particular drug dosage is released from a delivery system without the need for frequent administration. These are considered superior drug delivery system because of low cost, greater stability, non-toxicity, biocompatibility, non-immunogenicity, and are biodegradable in nature. This review also focus on the importance and ideal features of periodontal pockets as a drug delivery platform for designing a suitable dosage form along with its potential advantage and limitations. The microbes in the periodontal pocket could destroy periodontal tissues, and a complete knowledge of these as well as an ideal treatment strategy could be helpful in treating this disease.

A Review of Antimicrobial Peptides and Their Therapeutic Potential as Anti-Infective Drugs

Science.gov (United States)

Gordon, Y. Jerold; Romanowski, Eric G.; McDermott, Alison M.

2006-01-01

Purpose. Antimicrobial peptides (AMPs) are an essential part of innate immunity that evolved in most living organisms over 2.6 billion years to combat microbial challenge. These small cationic peptides are multifunctional as effectors of innate immunity on skin and mucosal surfaces and have demonstrated direct antimicrobial activity against various bacteria, viruses, fungi, and parasites. This review summarizes their progress to date as commercial antimicrobial drugs for topical and systemic indications. Methods. Literature review. Results. Despite numerous clinical trials, no modified AMP has obtained Food & Drug Administration approval yet for any topical or systemic medical indications. Conclusions. While AMPs are recognized as essential components of natural host innate immunity against microbial challenge, their usefulness as a new class of antimicrobial drugs still remains to be proven. PMID:16020284

[Potential antimicrobial drug interactions in clinical practice: consequences of polypharmacy and multidrug resistance].

Science.gov (United States)

Martínez-Múgica, Cristina

2015-12-01

Polypharmacy is a growing problem nowadays, which can increase the risk of potential drug interactions, and result in a loss of effectiveness. This is particularly relevant to the anti-infective therapy, especially when infection is produced by resistant bacteria, because therapeutic options are limited and interactions can cause treatment failure. All antimicrobial prescriptions were retrospectively reviewed during a week in the Pharmacy Department, in order to detect potential drug-interactions and analysing their clinical significance. A total of 314 antimicrobial prescriptions from 151 patients were checked. There was at least one potential interaction detected in 40% of patients, being more frequent and severe in those infected with multidrug-resistant microorganisms. Drugs most commonly involved were quinolones, azoles, linezolid and vancomycin. Potential drug interactions with antimicrobial agents are a frequent problem that can result in a loss of effectiveness. This is why they should be detected and avoided when possible, in order to optimize antimicrobial therapy, especially in case of multidrug resistant infections.

Self-medication with antimicrobial drugs in Europe

NARCIS (Netherlands)

Grigoryan, L; Haaijer-Ruskamp, FM; Burgerhof, JGM; Mechtler, R; Deschepper, R; Tambic-Andrasevic, A; Andrajati, R; Monnet, DL; Cunney, R; Di Matteo, A; Edelstein, H; Valinteliene, R; Alkerwi, A; Scicluna, EA; Grzesiowski, P; Bara, AC; Tesar, T; Cizman, M; Campos, J; Lundborg, CS; Birkin, J

We surveyed the populations of 19 European countries to compare the prevalence of antimicrobial drug self-medication in the previous 12 months and intended self-medication and storage and to identify the associated demographic characteristics. By using a multistage sampling design, 1,000-3,000

Antimicrobial drug resistance of Escherichia coli isolated from poultry abattoir workers at risk and broilers on antimicrobials

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J.W. Oguttu

2008-05-01

Full Text Available Antimicrobial usage in food animals increases the prevalence of antimicrobial drug resistance among their enteric bacteria. It has been suggested that this resistance can in turn be transferred to people working with such animals, e.g. abattoir workers. Antimicrobial drug resistance was investigated for Escherichia coli from broilers raised on feed supplemented with antimicrobials, and the people who carry out evisceration, washing and packing of intestines in a high-throughput poultry abattoir in Gauteng, South Africa. Broiler carcasses were sampled from 6 farms, on each of which broilers are produced in a separate 'grow-out cycle'. Per farm, 100 caeca were randomly collected 5 minutes after slaughter and the contents of each were selectively cultured for E. coli. The minimum inhibitory concentration (MIC of each isolate was determined for the following antimicrobials : doxycycline, trimethoprim, sulphamethoxazole, ampicillin, enrofloxacin, fosfomycin, ceftriaxone and nalidixic acid. The same was determined for the faeces of 29 abattoir workers and 28 persons used as controls. The majority of isolates from broilers were resistant, especially to antimicrobials that were used on the farms in the study. Overall median MICs and the number of resistant isolates from abattoir workers (packers plus eviscerators tended to be higher than for the control group. However, no statistically significant differences were observed when the median MICs of antimicrobials used regularly in poultry and percentage resistance were compared, nor could an association between resistance among the enteric E. coli from packers and those from broilers be demonstrated.

Pharmacokinetic drug interactions of antimicrobial drugs : a systematic review on oxazolidinones, rifamycines, macrolides, fluoroquinolones, and Beta-lactams

NARCIS (Netherlands)

Bolhuis, Mathieu S; Panday, Prashant N; Pranger, Arianna D; Kosterink, Jos G W; Alffenaar, Jan-Willem C

2011-01-01

Like any other drug, antimicrobial drugs are prone to pharmacokinetic drug interactions. These drug interactions are a major concern in clinical practice as they may have an effect on efficacy and toxicity. This article provides an overview of all published pharmacokinetic studies on drug

75 FR 37450 - Draft Guidance: The Judicious Use of Medically Important Antimicrobial Drugs in Food-Producing...

Science.gov (United States)

2010-06-29

... animals in order to help minimize antimicrobial resistance development. Based on a consideration of the...] Draft Guidance: The Judicious Use of Medically Important Antimicrobial Drugs in Food-Producing Animals... Medically Important Antimicrobial Drugs in Food- Producing Animals.'' This draft guidance is intended to...

Therapeutic Potential of Plants as Anti-Microbials for Drug Discovery

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Ramar Perumal Samy

2010-01-01

Full Text Available The uses of traditional medicinal plants for primary health care have steadily increased worldwide in recent years. Scientists are in search of new phytochemicals that could be developed as useful anti-microbials for treatment of infectious diseases. Currently, out of 80% of pharmaceuticals derived from plants, very few are now being used as anti-microbials. Plants are rich in a wide variety of secondary metabolites that have found anti-microbial properties. This review highlights the current status of traditional medicine, its contribution to modern medicine, recent trends in the evaluation of anti-microbials with a special emphasis upon some tribal medicine, in vitro and in vivo experimental design for screening, and therapeutic efficacy in safety and human clinical trails for commercial outlet. Many of these commercially available compounds are crude preparations administered without performing human clinical trials. Recent methods are useful to standardize the extraction for scientific investigation of new phytochemicals and anti-microbials of traditionally used plants. It is concluded that once the local ethnomedical preparations of traditional sources are scientifically evaluated before dispensing they should replace existing drugs commonly used for the therapeutic treatment of infection. This method should be put into practice for future investigations in the field of ethnopharmacology, phytochemistry, ethnobotany and other biological fields for drug discovery.

Antimicrobial drugs encapsulated in fibrin nanoparticles for treating microbial infested wounds.

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Alphonsa, B Maria; Sudheesh Kumar, P T; Praveen, G; Biswas, Raja; Chennazhi, K P; Jayakumar, R

2014-05-01

In vitro evaluation of antibacterial and antifungal drugs encapsulated fibrin nanoparticles to prove their potential prospect of using these nanocomponent for effective treatment of microbial infested wounds. Surfactant-free oil-in-water emulsification-diffusion method was adopted to encapsulate 1 mg/ml each of antimicrobial drugs (Ciprofloxacin and Fluconazole) in 4 ml of aqueous fibrinogen suspension and subsequent thrombin mediated cross linking to synthesize drug loaded fibrin nanoparticles. Ciprofloxacin loaded fibrin nanoparticles (CFNPs) showed size range of 253 ± 6 nm whereas that of Fluconazole loaded fibrin nanoparticles (FFNPs) was 260 ± 10 nm. Physico chemical characterizations revealed the firm integration of antimicrobial drugs within fibrin nanoparticles. Drug release studies performed at physiological pH 7.4 showed a release of 16% ciprofloxacin and 8% of fluconazole while as the release of ciprofloxacin at alkaline pH 8.5, was 48% and that of fluconazole was 37%. The antimicrobial activity evaluations of both drug loaded systems independently showed good antibacterial activity against Escherichia coli (E.coli), Staphylococcus aureus (S. aureus) and antifungal activity against Candida albicans (C. albicans). The in vitro toxicity of the prepared drug loaded nanoparticles were further analyzed using Human dermal fibroblast cells (HDF) and showed adequate cell viability. The efficacies of both CFNPs and FFNPs for sustained delivery of encapsulated anti microbial drugs were evaluated in vitro suggesting its potential use for treating microbial infested wounds (diabetic foot ulcer).

Increased Risk for ESBL-Producing Bacteria from Co-administration of Loperamide and Antimicrobial Drugs for Travelers' Diarrhea.

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Kantele, Anu; Mero, Sointu; Kirveskari, Juha; Lääveri, Tinja

2016-01-01

Antimicrobial drug treatment of travelers' diarrhea is known to increase the risk for colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae. Among 288 travelers with travelers' diarrhea, the colonization rate without medications was 21%. For treatment with loperamide only, the rate was 20%; with antimicrobial drugs alone, 40%; and with loperamide and antimicrobial drugs, 71%.

Antimicrobial drug use and related management practices among Ontario swine producers.

OpenAIRE

Dunlop, R H; McEwen, S A; Meek, A H; Friendship, R A; Clarke, R C; Black, W D

1998-01-01

A mail survey of swine producers in Ontario was undertaken during 1991 to describe the types, frequency, and motives for antimicrobial use. Two hundred operations that marketed fewer than 350 hogs per year, and 800 that marketed more than 350 per year were sent questionnaires, 63% of which were completed and returned. Most operations (86%) added antimicrobials to starter (weanling pig) rations, while fewer (29%) added these drugs to finisher pig rations. The most commonly used antimicrobials ...

Antimicrobial drugs for treating cholera.

Science.gov (United States)

Leibovici-Weissman, Ya'ara; Neuberger, Ami; Bitterman, Roni; Sinclair, David; Salam, Mohammed Abdus; Paul, Mical

2014-06-19

Cholera is an acute watery diarrhoea caused by infection with the bacterium Vibrio cholerae, which if severe can cause rapid dehydration and death. Effective management requires early diagnosis and rehydration using oral rehydration salts or intravenous fluids. In this review, we evaluate the additional benefits of treating cholera with antimicrobial drugs. To quantify the benefit of antimicrobial treatment for patients with cholera, and determine whether there are differences between classes of antimicrobials or dosing schedules. We searched the Cochrane Infectious Disease Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; African Index Medicus; LILACS; Science Citation Index; metaRegister of Controlled Trials; WHO International Clinical Trials Registry Platform; conference proceedings; and reference lists to March 2014. Randomized and quasi-randomized controlled clinical trials in adults and children with cholera that compared: 1) any antimicrobial treatment with placebo or no treatment; 2) different antimicrobials head-to-head; or 3) different dosing schedules or different durations of treatment with the same antimicrobial. Two reviewers independently applied inclusion and exclusion criteria, and extracted data from included trials. Diarrhoea duration and stool volume were defined as primary outcomes. We calculated mean difference (MD) or ratio of means (ROM) for continuous outcomes, with 95% confidence intervals (CI), and pooled data using a random-effects meta-analysis. The quality of evidence was assessed using the GRADE approach. Thirty-nine trials were included in this review with 4623 participants. Antimicrobials versus placebo or no treatment Overall, antimicrobial therapy shortened the mean duration of diarrhoea by about a day and a half compared to placebo or no treatment (MD -36.77 hours, 95% CI -43.51 to -30.03, 19 trials, 1013 participants, moderate quality evidence). Antimicrobial therapy also

Veterinary Medicine Needs New Green Antimicrobial Drugs

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Pierre-Louis TOUTAIN

2016-08-01

Full Text Available Given that: (1 the worldwide consumption of antimicrobial drugs (AMDs used in food-producing animals will increase over the coming decades; (2 the prudent use of AMDs will not suffice to stem the rise in human antimicrobial resistance (AMR of animal origin; (3 alternatives to AMD use are not available or not implementable, there is an urgent need to develop novel AMDs for food-producing animals. This is not for animal health reasons, but to break the link between human and animal resistomes. In this review we establish the feasibility of developing for veterinary medicine new AMDs, termed green antibiotics, having minimal ecological impact on the animal commensal and environmental microbiomes.We first explain why animal and human commensal microbiota comprise a turnstile exchange, between the human and animal resistomes. We then outline the ideal physico-chemical, pharmacokinetic and pharmacodynamic properties of a veterinary green antibiotic and conclude that they can be developed through a rational screening of currently used AMD classes. The ideal drug will be hydrophilic, of relatively low potency, slow clearance and small volume of distribution. It should be eliminated principally by the kidney as inactive metabolite(s. For oral administration, bioavailability can be enhanced by developing lipophilic pro-drugs. For parenteral administration, slow-release formulations of existing eco-friendly AMDs with a short elimination half-life can be developed. These new eco-friendly veterinary AMDs can be developed from currently used drug classes to provide alternative agents to those currently used in veterinary medicine and mitigate animal contributions to the human AMR problem.

VECTOR THEORY AND OPTIMAL CHOICE OF ANTIMICROBIAL DRUG FOR LOCAL WOUND TREATMENT

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Boyko N. N

2016-12-01

Full Text Available Introduction. One of important problems in the field of medicine and pharmacy is an optimal choice among several alternatives. For example, the choice of drugs for treatment among several analogs, selection of excipients among analogs for development of pharmaceutical forms with optimal pharmacological, technological and economical parameters, etc.The aim of the work is to show the possibility of vector theory use for optimal choice of antimicrobial drugs for local wound treatment among analogs taking into account several criteria at the same time. Materials and methods. For our investigation we have chosen ten drugs with antimicrobial properties for local wound treatment in different pharmaceutical forms (ointment, liniment, water and glycerin solution, tincture. We have determined antibacterial activity of drugs by agar well diffusion method on six test-stain microorganisms: Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Proteus vulgaris ATCC 4636, Bacillus subtilis ATCC 6633, and Candida albicans ATCC 885-653. Well diameter was 10 mm, the volume of drug in the well was 0.27±0.02 ml, microbial burden of agar upper layer was 107 CFU/ml, and total layer height in Petri dish was 4.0±0.5 mm. In order to integrate various qualitative and quantitative parameters into one index (vector object in multidimensional factors’ space we modify these parameters to non-dimensional normalized values. For this purpose we use a desirability theory. We have chosen the following criteria for optimal choice of the drug: antimicrobial activity (integrated index of drug’s antimicrobial activity, drug’s price, pharmacological and technological index, spectrum of drug’s action on test strains of microorganisms studied. Results and their discussions. Using vector and desirability theory, we have obtained the following range of drugs in decreasing order: Laevomecol ointment, Ioddicerinum, Tincture of Sophora

Synergism between plant extract and antimicrobial drugs used on Staphylococcus aureus diseases

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Joyce Elaine Cristina Betoni

2006-06-01

Full Text Available Searches for substances with antimicrobial activity are frequent, and medicinal plants have been considered interesting by some researchers since they are frequently used in popular medicine as remedies for many infectious diseases. The aim of this study was to verify the synergism between 13 antimicrobial drugs and 8 plant extracts - "guaco" (Mikania glomerata, guava (Psidium guajava, clove (Syzygium aromaticum, garlic (Allium sativum, lemongrass (Cymbopogon citratus, ginger (Zingiber officinale, "carqueja" (Baccharis trimera, and mint (Mentha piperita - against Staphylococcus aureus strains, and for this purpose, the disk method was the antimicrobial susceptibility test performed. Petri dishes were prepared with or without dilution of plant extracts at sub-inhibitory concentrations in Mueller-Hinton Agar (MHA, and the inhibitory zones were recorded in millimeters. In vitro anti-Staphylococcus aureus activities of the extracts were confirmed, and synergism was verified for all the extracts; clove, guava, and lemongrass presented the highest synergism rate with antimicrobial drugs, while ginger and garlic showed limited synergistic capacity.

Treatment practices and quantification of antimicrobial drug usage in conventional and organic dairy farms in Wisconsin.

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Pol, M; Ruegg, P L

2007-01-01

The objective of this study was to develop a method to quantify antimicrobial drug usage and treatment practices on conventional and organic dairy farms that had been recruited to represent a broad spectrum of potential exposure to antimicrobial drugs. Data on disease prevalence and treatment practices of organic (n = 20) and conventional (n = 20) farms were obtained during a farm visit using a survey instrument. A standardized estimate of antimicrobial drug usage was developed using a defined daily dose (DDD) of selected compounds. Density of antimicrobial drug usage was expressed as the number of DDD per adult cow per year. Differences in prevalence and management of selected diseases between conventional and organic farms were identified. The overall estimated prevalence of selected diseases was greater for conventional farms compared with organic farms. Organic farmers reported use of a variety of nonantimicrobial compounds for treatment and prevention of disease. Conventional farmers reported that penicillin was the compound most commonly used for dry cow therapy and cephapirin was most commonly used for treatment of clinical mastitis. On conventional farms, the estimated overall exposure to antimicrobial drugs was 5.43 DDD per cow per year composed of 3.58 and 1.85 DDD of intramammary and parenteral antimicrobial drugs, respectively. Of total intramammary antimicrobial drug usage, treatment of clinical mastitis contributed 2.02 DDD compared with 1.56 DDD attributed to the use of dry cow therapy. Of total parenteral treatments, the distribution of exposure was 0.52 (dry cow therapy), 1.43 (clinical mastitis treatment), 0.39 (treatment of foot disease), 0.14 (treatment of respiratory disease), and 0.32 (treatment of metritis) DDD. For treatments of foot infections (0.33 DDD), respiratory infections (0.07 DDD), and metritis (0.19 DDD), the mean density of ceftiofur usage was significantly greater compared with other compounds.

A long and winding road; evolution of antimicrobial drug development - crisis management.

Science.gov (United States)

Echols, Roger M

2012-11-01

The development of antimicrobial drugs has evolved from observational case reports to complex randomized prospective clinical trials in specific treatment indications. Beginning around the year 2000, the US FDA has evolved its approach on study design and other study characteristics, which has made the conduct of these studies more difficult and the outcomes for sponsors more risky. This has contributed to the decline in the discovery and development of new antimicrobials, which are needed to address the increasing problem of bacterial resistance to existing marketed products. This study reviews the historical basis for the current regulatory climate including the various crises that have led to considerable political pressures on the agency. Recent efforts to resolve development uncertainties and to provide economic incentives for future antimicrobial drug development are presented.

New Antimicrobial Approaches: Reuse of Old Drugs.

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Savoia, Dianella

2016-01-01

The global situation of antibiotic resistance and the reduction of investments in antibiotics research by the pharmaceutical industry suggest the need for specific cost-effective approaches in order to identify drugs for the therapy of many microbial infections. Among the viable alternative anti-infective compounds, drug repurposing, i.e. to find new uses for previously approved medicines, revealed some encouraging in vitro and in vivo results. In this article the reader has a panoramic view of the updated references on the strategies encountered during the repositioning process. New findings are reported about the anti-microbial efficacy of antipsychotic, cardiovascular, anti-inflammatory and anti-neoplastic drugs. This approach may enhance the portfolio of pharmaceutical companies reducing the need for pharmacokinetic and toxicity studies; the development of new uses of old drugs for different infectious diseases, leading to better health for patients, also in poor, tropical countries, appears to be having better results.

Antimicrobial Activity and Modulatory Effect of Essential Oil from the Leaf of Rhaphiodon echinus (Nees & Mart) Schauer on Some Antimicrobial Drugs.

Science.gov (United States)

Duarte, Antonia Eliene; de Menezes, Irwin Rose Alencar; Bezerra Morais Braga, Maria Flaviana; Leite, Nadghia Figueiredo; Barros, Luiz Marivando; Waczuk, Emily Pansera; Pessoa da Silva, Maria Arlene; Boligon, Aline; Teixeira Rocha, João Batista; Souza, Diogo Onofre; Kamdem, Jean Paul; Melo Coutinho, Henrique Douglas; Escobar Burger, Marilise

2016-06-08

Rhaphiodon echinus is a weed plant used in the Brazilian folk medicinal for the treatment of infectious diseases. In this study, the essential oil of R. echinus leaf was investigated for its antimicrobial properties. The chemical constituents of the essential oil were characterized by GC-MS. The antimicrobial properties were determined by studying by the microdilution method the effect of the oil alone, and in combination with antifungal or antibiotic drugs against the fungi Candida albicans, Candida krusei and Candida tropicalis and the microbes Escherichia coli, Staphylococcus aureus and Pseudomonas. In addition, the iron (II) chelation potential of the oil was determined. The results showed the presence of β-caryophyllene and bicyclogermacrene in major compounds, and revealed a low antifungal and antibacterial activity of the essential oil, but a strong modulatory effect on antimicrobial drugs when associated with the oil. The essential oil showed iron (II) chelation activity. The GC-MS characterization revealed the presence of monoterpenes and sesquiterpenes in the essential oil and metal chelation potential, which may be responsible in part for the modulatory effect of the oil. These findings suggest that essential oil of R. echinus is a natural product capable of enhancing the antibacterial and antifungal activity of antimicrobial drugs.

Antimicrobial drugs for treating cholera

Science.gov (United States)

Leibovici-Weissman, Ya'ara; Neuberger, Ami; Bitterman, Roni; Sinclair, David; Salam, Mohammed Abdus; Paul, Mical

2014-01-01

Background Cholera is an acute watery diarrhoea caused by infection with the bacterium Vibrio cholerae, which if severe can cause rapid dehydration and death. Effective management requires early diagnosis and rehydration using oral rehydration salts or intravenous fluids. In this review, we evaluate the additional benefits of treating cholera with antimicrobial drugs. Objectives To quantify the benefit of antimicrobial treatment for patients with cholera, and determine whether there are differences between classes of antimicrobials or dosing schedules. Search methods We searched the Cochrane Infectious Disease Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; African Index Medicus; LILACS; Science Citation Index; metaRegister of Controlled Trials; WHO International Clinical Trials Registry Platform; conference proceedings; and reference lists to March 2014. Selection criteria Randomized and quasi-randomized controlled clinical trials in adults and children with cholera that compared: 1) any antimicrobial treatment with placebo or no treatment; 2) different antimicrobials head-to-head; or 3) different dosing schedules or different durations of treatment with the same antimicrobial. Data collection and analysis Two reviewers independently applied inclusion and exclusion criteria, and extracted data from included trials. Diarrhoea duration and stool volume were defined as primary outcomes. We calculated mean difference (MD) or ratio of means (ROM) for continuous outcomes, with 95% confidence intervals (CI), and pooled data using a random-effects meta-analysis. The quality of evidence was assessed using the GRADE approach. Main results Thirty-nine trials were included in this review with 4623 participants. Antimicrobials versus placebo or no treatment Overall, antimicrobial therapy shortened the mean duration of diarrhoea by about a day and a half compared to placebo or no treatment (MD -36.77 hours, 95% CI -43

The Road from Host-Defense Peptides to a New Generation of Antimicrobial Drugs

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Alicia Boto

2018-02-01

Full Text Available Host-defense peptides, also called antimicrobial peptides (AMPs, whose protective action has been used by animals for millions of years, fulfill many requirements of the pharmaceutical industry, such as: (1 broad spectrum of activity; (2 unlike classic antibiotics, they induce very little resistance; (3 they act synergically with conventional antibiotics; (4 they neutralize endotoxins and are active in animal models. However, it is considered that many natural peptides are not suitable for drug development due to stability and biodisponibility problems, or high production costs. This review describes the efforts to overcome these problems and develop new antimicrobial drugs from these peptides or inspired by them. The discovery process of natural AMPs is discussed, as well as the development of synthetic analogs with improved pharmacological properties. The production of these compounds at acceptable costs, using different chemical and biotechnological methods, is also commented. Once these challenges are overcome, a new generation of versatile, potent and long-lasting antimicrobial drugs is expected.

Antimicrobial drug use and related management practices among Ontario swine producers.

Science.gov (United States)

Dunlop, R H; McEwen, S A; Meek, A H; Friendship, R A; Clarke, R C; Black, W D

1998-02-01

A mail survey of swine producers in Ontario was undertaken during 1991 to describe the types, frequency, and motives for antimicrobial use. Two hundred operations that marketed fewer than 350 hogs per year, and 800 that marketed more than 350 per year were sent questionnaires, 63% of which were completed and returned. Most operations (86%) added antimicrobials to starter (weanling pig) rations, while fewer (29%) added these drugs to finisher pig rations. The most commonly used antimicrobials were tylosin, carbadox, and furazolidone in weanling pigs, and tylosin, lincomycin, and tetracycline in finishers. Water medication of grower-finisher pigs was practised on 25% of farms; 80% of farms had injected at least some grower-finisher pigs with antimicrobials in the 12 mo preceding the survey. Approximately 20% of operations that added antimicrobials to finisher rations did so for growth promotion purposes only, while others used them for disease treatment, prevention, control, or a combination of reasons. Among those not using antimicrobials in finisher rations, 83% did not believe they were necessary and 37% were concerned about the potential for residues in marketed hogs.

Hybrid combinations containing natural products and antimicrobial drugs that interfere with bacterial and fungal biofilms.

Science.gov (United States)

Zacchino, Susana A; Butassi, Estefanía; Cordisco, Estefanía; Svetaz, Laura A

2017-12-15

Biofilms contribute to the pathogenesis of many chronic and difficult-to eradicate infections whose treatment is complicated due to the intrinsic resistance to conventional antibiotics. As a consequence, there is an urgent need for strategies that can be used for the prevention and treatment of biofilm-associated infections. The combination therapy comprising an antimicrobial drug with a low molecular weight (MW) natural product and an antimicrobial drug (antifungal or antibacterial) appeared as a good alternative to eradicate biofilms. The aims of this review were to perform a literature search on the different natural products that have showed the ability of potentiating the antibiofilm capacity of antimicrobial drugs, to analyze which are the antimicrobial drugs most used in combination, and to have a look on the microbial species most used to prepare biofilms. Seventeen papers, nine on combinations against antifungal biofilms and eight against antibacterial biofilms were collected. Within the text, the following topics have been developed: breaf history of the discovery of biofilms; stages in the development of a biofilm; the most used methodologies to assess antibiofilm-activity; the natural products with capacity of eradicating biofilms when acting alone; the combinations of low MW natural products with antibiotics or antifungal drugs as a strategy for eradicating microbial biofilms and a list of the low MW natural products that potentiate the inhibition capacity of antifungal and antibacterial drugs against biofilms. Regarding combinations against antifungal biofilms, eight over the nine collected works were carried out with in vitro studies while only one was performed with in vivo assays by using Caenorhabditis elegans nematode. All studies use biofilms of the Candida genus. A 67% of the potentiators were monoterpenes and sesquiterpenes and six over the nine works used FCZ as the antifungal drug. The activity of AmpB and Caspo was enhanced in one and two

Changes in the equine fecal microbiota associated with the use of systemic antimicrobial drugs.

Science.gov (United States)

Costa, Marcio C; Stämpfli, Henry R; Arroyo, Luis G; Allen-Vercoe, Emma; Gomes, Roberta G; Weese, J Scott

2015-02-03

The intestinal tract is a rich and complex environment and its microbiota has been shown to have an important role in health and disease in the host. Several factors can cause disruption of the normal intestinal microbiota, including antimicrobial therapy, which is an important cause of diarrhea in horses. This study aimed to characterize changes in the fecal bacterial populations of healthy horses associated with the administration of frequently used antimicrobial drugs. Twenty-four adult mares were assigned to receive procaine penicillin intramuscularly (IM), ceftiofur sodium IM, trimethoprim sulfadiazine (TMS) orally or to a control group. Treatment was given for 5 consecutive days and fecal samples were collected before drug administration (Day 1), at the end of treatment (Days 5), and on Days 14 and 30 of the trial. High throughput sequencing of the V4 region of the 16S rRNA gene was performed using an Illumina MiSeq sequencer. Significant changes of population structure and community membership were observed after the use of all drugs. TMS caused the most marked changes on fecal microbiota even at higher taxonomic levels including a significant decrease of richness and diversity. Those changes were mainly due to a drastic decrease of Verrucomicrobia, specifically the "5 genus incertae sedis". Changes in structure and membership caused by antimicrobial administration were specific for each drug and may be predictable. Twenty-five days after the end of treatment, bacterial profiles were more similar to pre-treatment patterns indicating a recovery from changes caused by antimicrobial administration, but differences were still evident, especially regarding community membership. The use of systemic antimicrobials leads to changes in the intestinal microbiota, with different and specific responses to different antimicrobials. All antimicrobials tested here had some impact on the microbiota, but TMS significantly reduced bacterial species richness and diversity and

Antimicrobial drug use in food-producing animals and associated human health risks: what, and how strong, is the evidence?

Science.gov (United States)

Hoelzer, Karin; Wong, Nora; Thomas, Joe; Talkington, Kathy; Jungman, Elizabeth; Coukell, Allan

2017-07-04

Antimicrobial resistance is a public health threat. Because antimicrobial consumption in food-producing animals contributes to the problem, policies restricting the inappropriate or unnecessary agricultural use of antimicrobial drugs are important. However, this link between agricultural antibiotic use and antibiotic resistance has remained contested by some, with potentially disruptive effects on efforts to move towards the judicious or prudent use of these drugs. The goal of this review is to systematically evaluate the types of evidence available for each step in the causal pathway from antimicrobial use on farms to human public health risk, and to evaluate the strength of evidence within a 'Grades of Recommendations Assessment, Development and Evaluation'(GRADE) framework. The review clearly demonstrates that there is compelling scientific evidence available to support each step in the causal pathway, from antimicrobial use on farms to a public health burden caused by infections with resistant pathogens. Importantly, the pathogen, antimicrobial drug and treatment regimen, and general setting (e.g., feed type) can have significant impacts on how quickly resistance emerges or spreads, for how long resistance may persist after antimicrobial exposures cease, and what public health impacts may be associated with antimicrobial use on farms. Therefore an exact quantification of the public health burden attributable to antimicrobial drug use in animal agriculture compared to other sources remains challenging. Even though more research is needed to close existing data gaps, obtain a better understanding of how antimicrobial drugs are actually used on farms or feedlots, and quantify the risk associated with antimicrobial use in animal agriculture, these findings reinforce the need to act now and restrict antibiotic use in animal agriculture to those instances necessary to ensure the health and well-being of the animals.

Prospective study on quantitative and qualitative antimicrobial and anti-inflammatory drug use in white veal calves.

Science.gov (United States)

Pardon, Bart; Catry, Boudewijn; Dewulf, Jeroen; Persoons, Davy; Hostens, Miel; De Bleecker, Koen; Deprez, Piet

2012-04-01

To document and quantify drug use in white veal calves, an intensive livestock production system where multidrug resistance is abundantly present. Drug consumption data were prospectively collected on 15 white veal production cohorts (n = 5853 calves) in Belgium (2007-09). Treatment incidences (TIs) based on animal defined daily dose (ADD), prescribed daily dose (PDD) and used daily dose (UDD) were calculated. Risk factors were identified by linear regression. The average TI(ADD) of antimicrobial treatments was 416.8 ADD per 1000 animals at risk. Predominantly, oral group antimicrobial treatments were used (95.8%). Of the oral group antimicrobial treatments, 12% and 88% were used for prophylactic or metaphylactic indications, respectively. The main indication for group and individual drug use was respiratory disease. The most frequently used antimicrobials (group treatments) were oxytetracycline (23.7%), amoxicillin (18.5%), tylosin (17.2%) and colistin (15.2%). Deviations from the leaflet dosage recommendations were frequently encountered, with 43.7% of the group treatments underdosed (often oxytetracycline and tylosin to treat dysbacteriosis). In 33.3% of the oral antimicrobial group treatments a combination of two antimicrobial preparations was used. Smaller integrations used more antimicrobials in group treatments than larger ones (P < 0.05); an integration is defined as a company that combines all steps of the production chain by having its own feed plant and slaughterhouse and by placing its calves in veal herds owned by producers that fatten these calves for this integration on contract. Producers used higher dosages than prescribed by the veterinarian in cohorts with a single caretaker (P < 0.01). The present study provided detailed information on the intensive antimicrobial use in the white veal industry. Reduction can only be achieved by reducing the number of oral group treatments.

Antimicrobial peptides: a new class of antimalarial drugs?

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Nuno eVale

2014-12-01

Full Text Available A range of antimicrobial peptides (AMP exhibit activity on malaria parasites, Plasmodium spp, in their blood or mosquito stages, or both. These peptides include a diverse array of both natural and synthetic molecules varying greatly in size, charge, hydrophobicity and secondary structure features. Along with an overview of relevant literature reports regarding AMP that display antiplasmodial activity, this review makes a few considerations about those molecules as a potential new class of antimalarial drugs.

Effect of Antimicrobial Use in Agricultural Animals on Drug-resistant Foodborne Campylobacteriosis in Humans: A Systematic Literature Review.

Science.gov (United States)

McCrackin, M A; Helke, Kristi L; Galloway, Ashley M; Poole, Ann Z; Salgado, Cassandra D; Marriott, Bernadette P

2016-10-02

Controversy continues concerning antimicrobial use in food animals and its relationship to drug-resistant infections in humans. We systematically reviewed published literature for evidence of a relationship between antimicrobial use in agricultural animals and drug-resistant foodborne campylobacteriosis in humans. Based on publications from the United States (U.S.), Canada and Denmark from 2010 to July 2014, 195 articles were retained for abstract review, 50 met study criteria for full article review with 36 retained for which data are presented. Two publications reported increase in macrolide resistance of Campylobacter coli isolated from feces of swine receiving macrolides in feed, and one of these described similar findings for tetracyclines and fluoroquinolones. A study in growing turkeys demonstrated increased macrolide resistance associated with therapeutic dosing with Tylan® in drinking water. One publication linked tetracycline-resistant C. jejuni clone SA in raw cow's milk to a foodborne outbreak in humans. No studies that identified farm antimicrobial use also traced antimicrobial-resistant Campylobacter from farm to fork. Recent literature confirms that on farm antibiotic selection pressure can increase colonization of animals with drug-resistant Campylobacter spp. but is inadequately detailed to establish a causal relationship between use of antimicrobials in agricultural animals and prevalence of drug-resistant foodborne campylobacteriosis in humans.

Current Trends of Using Antimicrobial Drugs in the ICU at a Tertiary Level Teaching Hospital in Mymensingh.

Science.gov (United States)

Saha, S K; Shaha, K C; Haque, M F; Khatun, S; Akhter, S M; Akhter, H

2016-10-01

The aim of the present study was to investigate the current trends of using antimicrobial drugs in the ICU at a tertiary level teaching hospital in Mymensingh. The study of prescribing patterns seeks to monitor, evaluate and suggest modifications in clinicians prescribing habits so as to make medical care rational. It was an observational type of descriptive study, conducted in the Mymensingh medical college hospital, Mymensingh, during the study period of June 2016 to September 2016.The study was approved by the institutional ethical committee. Most patients in the ICU belonged to the older age group >60 years. Male patients were more than the female patients in ICU. Average duration of stay in ICU was 4.35 days. Admissions in ICU were common due to respiratory system related diseases and the present study showed that 31.68% of the reported cases belong to the respiratory system. Average number of drugs per prescription was 6.46. Average number of anti-microbial drugs per prescription was 1.38. Cephalosporin group and individually ceftriaxone was the most frequently prescribed antimicrobial group and agent respectively in the ICU. Most commonly used antimicrobial combination was Cephalosporin and Metronidazole (43.33%) followed by Carbapenem (Meropenem) and Metronidazole (13.33%). Most antimicrobial agents were prescribed without bacteriological culture and sensivity testing evidence. There is a need for motivating the physicians to prescribe antimicrobial agents with supportive bacteriological evidences.

In vitro antimicrobial activity of five essential oils on multi-drug resistant Gram-negative clinical isolates

Directory of Open Access Journals (Sweden)

Hercules Sakkas

2016-09-01

Conclusions: The antimicrobial activities of the essential oils are influenced by the strain origin (wild, reference, drug sensitive or resistant and it should be taken into consideration whenever investigating the plants’ potential for developing new antimicrobials. [J Complement Med Res 2016; 5(3.000: 212-218

Extent, quality and impact of patient and public involvement in antimicrobial drug development research: A systematic review.

Science.gov (United States)

Evans, David; Bird, Emma; Gibson, Andy; Grier, Sally; Chin, Teh Li; Stoddart, Margaret; MacGowan, Alasdair

2018-02-01

Patient and public involvement (PPI) is increasingly recognized as bringing a range of benefits to clinical and health services research. Recent systematic reviews have identified and synthesized many benefits (eg higher recruitment rates) and some costs (eg extra time need). Much of the literature focuses on PPI in long-term conditions rather than more acute health care in which the majority of microbiological research is undertaken. The aim was to identify the extent, quality and impact of PPI in antimicrobial drug development research. Objectives were to identify any relevant reporting of PPI in antimicrobial research; appraise the quality of reporting on PPI using recognized PPI reporting and critical appraisal tools; and extract and synthesize data on the impact of PPI. A systematic review was undertaken with a search strategy based on four word groups (PPI, patients, antimicrobial drug development and outcomes). Eight online databases were searched. English language publication, publication between 1996 and 2016 and studies describing PPI in antimicrobial drug development research. No studies were found through online searching that met the search strategy and inclusion criteria. One relevant protocol paper with a brief mention of PPI was identified through expert recommendation. Commentary papers recommending PPI were identified through website searching and expert opinion. Despite strong policy guidance encouraging PPI at the international and national levels, and anecdotal accounts of PPI taking place, evidence for the extent, quality and impact of PPI in antimicrobial drug development research has not yet appeared in the peer-reviewed literature. © 2017 The Authors Health Expectations Published by John Wiley & Sons Ltd.

Population mobility, globalization, and antimicrobial drug resistance.

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MacPherson, Douglas W; Gushulak, Brian D; Baine, William B; Bala, Shukal; Gubbins, Paul O; Holtom, Paul; Segarra-Newnham, Marisel

2009-11-01

Population mobility is a main factor in globalization of public health threats and risks, specifically distribution of antimicrobial drug-resistant organisms. Drug resistance is a major risk in healthcare settings and is emerging as a problem in community-acquired infections. Traditional health policy approaches have focused on diseases of global public health significance such as tuberculosis, yellow fever, and cholera; however, new diseases and resistant organisms challenge existing approaches. Clinical implications and health policy challenges associated with movement of persons across barriers permeable to products, pathogens, and toxins (e.g., geopolitical borders, patient care environments) are complex. Outcomes are complicated by high numbers of persons who move across disparate and diverse settings of disease threat and risk. Existing policies and processes lack design and capacity to prevent or mitigate adverse health outcomes. We propose an approach to global public health risk management that integrates population factors with effective and timely application of policies and processes.

Antimicrobial Drug-Resistant Shiga Toxin-Producing Escherichia coli Infections, Michigan, USA.

Science.gov (United States)

Mukherjee, Sanjana; Mosci, Rebekah E; Anderson, Chase M; Snyder, Brian A; Collins, James; Rudrik, James T; Manning, Shannon D

2017-09-01

High frequencies of antimicrobial drug resistance were observed in O157 and non-O157 Shiga toxin-producing E. coli strains recovered from patients in Michigan during 2010-2014. Resistance was more common in non-O157 strains and independently associated with hospitalization, indicating that resistance could contribute to more severe disease outcomes.

Antimicrobial agents are societal drugs: how should this influence prescribing?

Science.gov (United States)

Sarkar, Paul; Gould, Ian M

2006-01-01

This paper is concerned with how those who prescribe antimicrobials should consider the wider repercussions of their actions. It is accepted that in an ecological system, pressure will cause evolution; this is also the case with antimicrobials, the result being the development of resistance and the therapeutic failure of drugs. To an extent, this can be ameliorated through advances by the pharmaceutical industry, but that should not stop us from critically appraising our use and modifying our behavior to slow this process down. Up to 50% of prescribing in human medicine and 80% in veterinary medicine and farming has been considered questionable. The Alliance for the Prudent Use of Antimicrobials (APUA) was approached by the WHO to review the situation. Their recommendations include decreasing the prescribing of antibacterials for nonbacterial infections. In the UK, there has been an initiative called "the path of least resistance". This encourages general practitioners to avoid prescribing or reduce the duration of prescriptions for conditions such as upper respiratory tract infections and uncomplicated urinary tract infections; this approach has been successful. Another recommendation is to reduce the prescribing of broad-spectrum antibacterials. In UK hospitals, the problems identified with the inappropriate use of antibacterials are insufficient training in infectious disease, difficulty in selecting empirical antibacterial therapy, poor use of available microbiological information, the fear of litigation and the fact that the majority of antibacterials are prescribed by the least experienced doctors. With close liaison between the laboratories and clinicians, and the development of local protocols, this can be addressed. Another recommendation is to tighten the use of antibacterial prophylaxis and to improve patient compliance. Through a combination of improved education for doctors and patients, and improved communication skills, these problems can be

Quorum sensing inhibitory drugs as next generation antimicrobials: worth the effort?

DEFF Research Database (Denmark)

Bjarnsholt, Thomas; Givskov, M.

2008-01-01

as biofilms are more tolerant to antibiotics than their planktonic counterparts. Therefore, research should identify new antimicrobial agents and their corresponding targets to decrease the biofilm-forming capability or persistence of the infectious bacteria. Here, we review one such drug target: bacterial......Bacterial resistance poses a major challenge to the development of new antimicrobial agents. Conventional antibiotics have an inherent obsolescence because they select for development of resistance. Bacterial infections have again become a serious threat in developed countries. Particularly......, elderly, immunocompromised, and hospitalized patients are susceptible to infections caused by bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis. These bacteria form chronic, biofilm-based infections, which are challenging because bacterial cells living...

Ethical conflicts in public health research and practice: antimicrobial resistance and the ethics of drug development.

Science.gov (United States)

Aiello, Allison E; King, Nicholas B; Foxman, B

2006-11-01

Since the 1960s, scientists and pharmaceutical representatives have called for the advancement and development of new antimicrobial drugs to combat infectious diseases. In January 2005, Senate Majority Leader Bill Frist (R-TN), MD, introduced a biopreparedness bill that included provisions for patent extensions and tax incentives to stimulate industry research on new antimicrobials. Although government stimulus for private development of new antimicrobials is important, it does not resolve long-standing conflicts of interest between private entities and society. Rising rates of antimicrobial resistance have only exacerbated these conflicts. We used methicillin-resistant Staphylococcus aureus as a case study for reviewing these problems, and we have suggested alternative approaches that may halt the vicious cycle of resistance and obsolescence generated by the current model of antimicrobial production.

Hormonal and antimicrobial therapy in theriogenology practice: currently approved drugs in the USA and possible future directions.

Science.gov (United States)

Modric, T; Momcilovic, D; Gwin, W E; Peter, A T

2011-08-01

Hormonal and antimicrobial therapies are essential to regulate and maintain healthy reproduction in domestic animals. The appropriate and legal use of these compounds is ultimately the responsibility of the veterinarian and other users, with a primary mission to directly protect and promote the health of animals, and indirectly the health of people. The appropriate use of these products is defined by the Federal Food, Drug, and Cosmetic Act, 21 United States of America § 301 et seq and implementing regulations in the Code of Federal Regulations. In the past, use of a drug in an animal for an unapproved use violated this Act. However, passage of the Animal Medicinal Drug Use Clarification Act 1994 legalized the extra-label use of certain animal and human drugs in veterinary practice for treating diseases. This manuscript reviews currently approved hormonal and antimicrobial drugs for use in theriogenology. Considering the ever increasing knowledge in the area of veterinary reproduction, particularly in the treatment and control of reproduction using antimicrobials and hormones, it would be beneficial to widen the therapeutic options in these categories. The potential for widening the therapeutic options is also discussed in this review, by providing a non-exhaustive but essential list of potential new drugs for use in clinical animal reproduction (theriogenology). Copyright © 2011 Elsevier Inc. All rights reserved.

77 FR 22328 - Guidance for Industry on the Judicious Use of Medically Important Antimicrobial Drugs in Food...

Science.gov (United States)

2012-04-13

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2010-D-0094] Guidance for Industry on the Judicious Use of Medically Important Antimicrobial Drugs in Food-Producing Animals; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and...

Use of antimicrobial agents in aquaculture.

Science.gov (United States)

Park, Y H; Hwang, S Y; Hong, M K; Kwon, K H

2012-04-01

The aquaculture industry has grown dramatically, and plays an important role in the world's food supply chain. Antimicrobial resistance in bacteria associated with food animals receives much attention, and drug use in aquaculture is also an important issue. There are many differences between aquatic and terrestrial management systems, such as the methods used for administration of drugs. Unique problems are related to the application of drugs in aquatic environments. Residual drugs in fish products can affect people who consume them, and antimicrobials released into aquatic environments can select for resistant bacteria. Moreover, these antimicrobial-resistant bacteria, or their resistance genes, can be transferred to humans. To decrease the risks associated with the use of antimicrobials, various regulations have been developed. In addition, it is necessary to prevent bacterial diseases in aquatic animals by vaccination, to improve culture systems, and to monitor the amount of antimicrobial drugs used and the prevalence of antimicrobial-resistant bacteria.

N-heterocyclic carbene metal complexes as bio-organometallic antimicrobial and anticancer drugs.

Science.gov (United States)

Patil, Siddappa A; Patil, Shivaputra A; Patil, Renukadevi; Keri, Rangappa S; Budagumpi, Srinivasa; Balakrishna, Geetha R; Tacke, Matthias

2015-01-01

Late transition metal complexes that bear N-heterocyclic carbene (NHC) ligands have seen a speedy growth in their use as both, metal-based drug candidates and potentially active homogeneous catalysts in a plethora of C-C and C-N bond forming reactions. This review article focuses on the recent developments and advances in preparation and characterization of NHC-metal complexes (metal: silver, gold, copper, palladium, nickel and ruthenium) and their biomedical applications. Their design, syntheses and characterization have been reviewed and correlated to their antimicrobial and anticancer efficacies. All these initial discoveries help validate the great potential of NHC-metal derivatives as a class of effective antimicrobial and anticancer agents.

Animation of Antimicrobial Resistance

Medline Plus

Full Text Available ... Pin it Email Print The Food and Drug Administration's (FDA's) Center for Veterinary Medicine (CVM) produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in ...

The preparation, cytocompatibility and antimicrobial property of micro/nano structural titanium loading alginate and antimicrobial peptide

Science.gov (United States)

Liu, Zhiyuan; Zhong, Mou; Sun, Yuhua; Chen, Junhong; Feng, Bo

2018-03-01

Titanium with hybrid microporous/nanotubes (TMNT) structure on its surface was fabricated by acid etching and subsequently anodization at different voltages. Bovine lactoferricin, a kind of antimicrobial peptide, and sodium alginate (NaAlg) were loaded onto titanium surface through layer by layer assembly. The drug release, cytocompatibility and antimicrobial property against S.aureus and E.coil were studied by release experiment, osteoblast and bacterial cultures. Results indicated that samples with nanotubes of bigger diameter carried more drugs and had better biocompatibility, and drug-loaded samples acquired better biocompatibility compared with drug-free samples. Furthermore, the drug-loaded samples exhibited good initial antimicrobial property, but weak long-term antimicrobial property. Therefore, drug-loaded titanium with micro/nano structure, especially, of big diameter nanotubes, could be a promise material for medical implants, such as internal/external fixation devices.

In vitro antimicrobial activity of five essential oils on multi-drug resistant Gram-negative clinical isolates

OpenAIRE

Hercules Sakkas; Panagiota Gousia; Vangelis Economou; Vassilios Sakkas; Stefanos Petsios; Chrissanthy Papadopoulou

2016-01-01

Aim/Background: The emergence of drug-resistant pathogens has drawn attention on medicinal plants for potential antimicrobial properties. The objective of the present study was the investigation of the antimicrobial activity of five plant essential oils on multidrug resistant Gram-negative bacteria. Materials and Methods: Basil, chamomile blue, origanum, thyme, and tea tree oil were tested against clinical isolates of Acinetobacter baumannii (n = 6), Escherichia coli (n = 4), Klebsiella pneum...

Drug-induced liver injury due to antimicrobials, central nervous system agents, and nonsteroidal anti-inflammatory drugs.

Science.gov (United States)

Devarbhavi, Harshad; Andrade, Raúl J

2014-05-01

Antimicrobial agents including antituberculosis (anti-TB) agents are the most common cause of idiosyncratic drug-induced liver injury (DILI) and drug-induced liver failure across the world. Better molecular and genetic biomarkers are acutely needed to help identify those at risk of liver injury particularly for those needing antituberculosis therapy. Some antibiotics such as amoxicillin-clavulanate and isoniazid consistently top the lists of agents in retrospective and prospective DILI databases. Central nervous system agents, particularly antiepileptics, account for the second most common class of agents implicated in DILI registries. Hepatotoxicity from older antiepileptics such as carbamazepine, phenytoin, and phenobarbital are often associated with hypersensitivity features, whereas newer antiepileptic drugs have a more favorable safety profile. Antidepressants and nonsteroidal anti-inflammatory drugs carry very low risk of significant liver injury, but their prolific use make them important causes of DILI. Early diagnosis and withdrawal of the offending agent remain the mainstays of minimizing hepatotoxicity. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Animation of Antimicrobial Resistance

Medline Plus

Full Text Available ... how antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the development of resistant strains of bacteria, complicating clinician's efforts to select the appropriate antimicrobial ...

In vitro and in vivo analysis of antimicrobial agents alone and in combination against multi-drug resistant Acinetobacter baumannii

Directory of Open Access Journals (Sweden)

Songzhe eHE

2015-05-01

Full Text Available Objective To investigate the in vitro and in vivo antibacterial activities of tigecycline and other 13 common antimicrobial agents, alone or in combination, against multi-drug resistant Acinetobacter baumannii.MethodsAn in vitro susceptibility test of 101 Acinetobacter baumannii was used to detect minimal inhibitory concentrations (MICs. A mouse lung infection model of multi-drug resistant Acinetobacter baumannii,established by the ultrasonic atomization method, was used to define in vivo antimicrobial activities.Results Multi-drug resistant Acinetobacter baumannii showed high sensitivity to tigecycline (98% inhibition, polymyxin B (78.2% inhibition, and minocycline (74.2% inhibition. However, the use of these antimicrobial agents in combination with other antimicrobial agents produced synergistic or additive effects. In vivo data showed that white blood cell (WBC counts in drug combination groups C (minocycline + amikacin and D (minocycline + rifampicin were significantly higher than in groups A (tigecycline and B (polymyxin B (P < 0.05, after administration of the drugs 24h post-infection. Lung tissue inflammation gradually increased in the model group during the first 24h after ultrasonic atomization infection; vasodilation, congestion with hemorrhage were observed 48h post infection. After three days of anti-infective therapy in groups A, B, C and D, lung tissue inflammation in each group gradually recovered with clear structures. The mortality rates in drug combination groups (groups C and D were much lower than in groups A and B.ConclusionThe combination of minocycline with either rifampicin or amikacin is more effective against multidrug-resistant Acinetobacter baumannii than single-agent tigecycline or polymyxin B. In addition, the mouse lung infection by ultrasonic atomization is a suitable model for drug screening and analysis of infection mechanism.

Antimicrobial resistance determinant microarray for analysis of multi-drug resistant isolates

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Taitt, Chris Rowe; Leski, Tomasz; Stenger, David; Vora, Gary J.; House, Brent; Nicklasson, Matilda; Pimentel, Guillermo; Zurawski, Daniel V.; Kirkup, Benjamin C.; Craft, David; Waterman, Paige E.; Lesho, Emil P.; Bangurae, Umaru; Ansumana, Rashid

2012-06-01

The prevalence of multidrug-resistant infections in personnel wounded in Iraq and Afghanistan has made it challenging for physicians to choose effective therapeutics in a timely fashion. To address the challenge of identifying the potential for drug resistance, we have developed the Antimicrobial Resistance Determinant Microarray (ARDM) to provide DNAbased analysis for over 250 resistance genes covering 12 classes of antibiotics. Over 70 drug-resistant bacteria from different geographic regions have been analyzed on ARDM, with significant differences in patterns of resistance identified: genes for resistance to sulfonamides, trimethoprim, chloramphenicol, rifampin, and macrolide-lincosamidesulfonamide drugs were more frequently identified in isolates from sources in Iraq/Afghanistan. Of particular concern was the presence of genes responsible for resistance to many of the last-resort antibiotics used to treat war traumaassociated infections.

Dexamethasone abrogates the antimicrobial and antibiofilm activities of different drugs against clinical isolates of Staphylococcus aureus and Pseudomonas aeruginosa

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Aquila Rodrigues

2017-01-01

Full Text Available Staphylococcus aureus and Pseudomonas aeruginosa are part of the human microbiota and are also important bacterial pathogens, for which therapeutic options are lacking nowadays. The combined administration of corticosteroids and antimicrobials is commonly used in the treatment of infectious diseases to control inflammatory processes and to minimize potential toxicity of antimicrobials, avoiding sequelae. Although different pharmaceutical dosage forms of antimicrobials combined to corticosteroids are available, studies on the interference of corticosteroids on the pharmacological activity of antimicrobials are scarce and controversial. Here, we provide evidence of the interference of dexamethasone on the pharmacological activity of clinically important antimicrobial drugs against biofilms and planktonic cells of S. aureus and P. aeruginosa. Broth microdilution assays of minimal inhibitory concentration (MIC, minimum bactericidal concentration (MBC, and minimum biofilm eradication concentration (MBEC of gentamicin, chloramphenicol, oxacillin, ceftriaxone and meropenem were conducted with and without the addition of dexamethasone. The effect of all drugs was abrogated by dexamethasone in their MIC, MBC, and MBEC, except gentamicin and meropenem, for which the MBC was not affected in some strains. The present study opens doors for more investigations on in vitro and in vivo effects and safety of the combination of antimicrobials and glucocorticoids.

Bio-inspired crosslinking and matrix-drug interactions for advanced wound dressings with long-term antimicrobial activity.

Science.gov (United States)

Dhand, Chetna; Venkatesh, Mayandi; Barathi, Veluchami Amutha; Harini, Sriram; Bairagi, Samiran; Goh Tze Leng, Eunice; Muruganandham, Nandhakumar; Low, Kenny Zhi Wei; Fazil, Mobashar Hussain Urf Turabe; Loh, Xian Jun; Srinivasan, Dinesh Kumar; Liu, Shou Ping; Beuerman, Roger W; Verma, Navin Kumar; Ramakrishna, Seeram; Lakshminarayanan, Rajamani

2017-09-01

There is a growing demand for durable advanced wound dressings for the management of persistent infections after deep burn injuries. Herein, we demonstrated the preparation of durable antimicrobial nanofiber mats, by taking advantage of strong interfacial interactions between polyhydroxy antibiotics (with varying number of OH groups) and gelatin and their in-situ crosslinking with polydopamine (pDA) using ammonium carbonate diffusion method. Polydopamine crosslinking did not interfere with the antimicrobial efficacy of the loaded antibiotics. Interestingly, incorporation of antibiotics containing more number of alcoholic OH groups (N OH  ≥ 5) delayed the release kinetics with complete retention of antimicrobial activity for an extended period of time (20 days). The antimicrobials-loaded mats displayed superior mechanical and thermal properties than gelatin or pDA-crosslinked gelatin mats. Mats containing polyhydroxy antifungals showed enhanced aqueous stability and retained nanofibrous morphology under aqueous environment for more than 4 weeks. This approach can be expanded to produce mats with broad spectrum antimicrobial properties by incorporating the combination of antibacterial and antifungal drugs. Direct electrospinning of vancomycin-loaded electrospun nanofibers onto a bandage gauze and subsequent crosslinking produced non-adherent durable advanced wound dressings that could be easily applied to the injured sites and readily detached after treatment. In a partial thickness burn injury model in piglets, the drug-loaded mats displayed comparable wound closure to commercially available silver-based dressings. This prototype wound dressing designed for easy handling and with long-lasting antimicrobial properties represents an effective option for treating life-threatening microbial infections due to thermal injuries. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

THE EFFECT OF DIFFERENT TB DRUGS AND ANTIMICROBIAL AGENTS ON THE EFFICIENCY OF TREATMENT OF TUBERCULOSIS PATIENTS WITH MULTIPLE DRUG RESISTANCE

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I. A. Vasilyeva

2017-01-01

Full Text Available Objective of the study: to study the effect of specific TB drugs and antimicrobial agents constituting chemotherapy regimens on the efficiency of treatment of tuberculosis patients with various patterns of multiple drug resistance.Subjects and Methods. 412 pulmonary tuberculosis patients with bacillary excretion and various patterns of multiple drug resistance were enrolled into the study (117 patients with MDR TB (non pre-XDR and non-XDR; 120 patients with pre-XDR TB and 175 with XDR TB. Patients in the subgroups were compatible regarding sex and age. The patients were prescribed regimens including 5-6 drugs in accordance with their drug resistance pattern. The time of sputum conversion (by culture versus the year of treatment was selected as a surrogate endpoint. The effect of specific TB drugs and antimicrobial agents on treatment efficiency was assessed through calculation of odds ratio (OR of achieving a surrogate endpoint in the patients receiving and not receiving a certain drug.Results. In the subgroup of pre-XDR TB, the following drugs demonstrated the valid increase of odds of sputum conversion: ethambutol (OR 11.8, pyrazinamide (OR 10.2, moxifloxacin (OR 7.8, capreomicin (OR 4.41. Sputum conversion was achieved in all 11 patients treated with bedaquiline.In the subgroup of XDR TB, the following drugs provided a positive effect on the achievement of sputum conversion: bedaquiline (OR 9.62, linezolid (OR 8.15, cycloserine (OR 7.88, pyrazinamide (OR 7.29, moxifloxacin (OR 7.08, and ethambutol (OR 6.69. Ofloxacin demonstrated a confident negative effect on achieving sputum conversion (95% CI 0.06-0.32. 

Antimicrobial drug resistance of Salmonella isolates from meat and humans, Denmark

DEFF Research Database (Denmark)

Skov, Marianne Nielsine; Andersen, Jens Strodl; Aabo, Søren

2007-01-01

We compared 8,144 Salmonella isolates collected from meat imported to or produced in Denmark, as well as from Danish patients. Isolates from imported meat showed a higher rate of antimicrobial drug resistance, including multidrug resistance, than did isolates from domestic meat. Isolates from...... humans showed resistance rates lower than those found in imported meat but higher than in domestic meat. These findings indicate that programs for controlling resistant Salmonella spp. are a global issue...

Antimicrobial drug resistance of Salmonella isolates from meat and humans, Denmark

DEFF Research Database (Denmark)

Skov, Marianne; Andersen, Jens Strodl; Aabo, Søren

2007-01-01

We compared 8,144 Salmonella isolates collected from meat imported to or produced in Denmark, as well as from Danish patients. Isolates from imported meat showed a higher rate of antimicrobial drug resistance, including multidrug resistance, than did isolates from domestic meat. Isolates from...... humans showed resistance rates lower than those found in imported meat but higher than in domestic meat. These findings indicate that programs for controlling resistant Salmonella spp. are a global issue....

An update discussion on the current assessment of the safety of veterinary antimicrobial drug residues in food with regard to their impact on the human intestinal microbiome.

Science.gov (United States)

Cerniglia, Carl E; Pineiro, Silvia A; Kotarski, Susan F

2016-05-01

The human gastrointestinal tract ecosystem consists of complex and diverse microbial communities that have now been collectively termed the intestinal microbiome. Recent scientific breakthroughs and research endeavours have increased our understanding of the important role the intestinal microbiome plays in human health and disease. The use of antimicrobial new animal drugs in food-producing animals may result in the presence of low levels of drug residues in edible foodstuffs. There is concern that antimicrobial new animal drugs in or on animal-derived food products at residue-level concentrations could disrupt the colonization barrier and/or modify the antimicrobial resistance profile of human intestinal bacteria. Therapeutic doses of antimicrobial drugs have been shown to promote shifts in the intestinal microbiome, and these disruptions promote the emergence of antimicrobial-resistant bacteria. To assess the effects of antimicrobial new animal drug residues in food on human intestinal bacteria, many national regulatory agencies and international committees follow a harmonized process, VICH GL36(R), which was issued by a trilateral organization of the European Union, the USA, and Japan called the International Cooperation on Harmonization of Technical Requirements for Veterinary Medicinal Products (VICH). The guidance describes a general approach currently used by national regulatory agencies and international committees to assess the effects of antimicrobial new animal drug residues in animal-derived food on human intestinal bacteria. The purpose of this review is to provide an overview of this current approach as part of the antimicrobial new animal drug approval process in participating countries, give insights on the microbiological endpoints used in this safety evaluation, and discuss the availability of new information. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Antimicrobial activity of Nigerian medicinal plants

Science.gov (United States)

Anyanwu, Madubuike Umunna; Okoye, Rosemary Chinazam

2017-01-01

Antimicrobial resistance (AMR) is currently one of the major threats facing mankind. The emergence and rapid spread of multi- and pan-drug-resistant organisms (such as vancomycin-, methicillin-, extended-spectrum β-lactam-, carbapenem- and colistin-resistant organisms) has put the world in a dilemma. The health and economic burden associated with AMR on a global scale are dreadful. Available antimicrobials have been misused and are almost ineffective with some of these drugs associated with dangerous side effects in some individuals. Development of new, effective, and safe antimicrobials is one of the ways by which AMR burden can be reduced. The rate at which microorganisms develop AMR mechanisms outpaces the rate at which new antimicrobials are being developed. Medicinal plants are potential sources of new antimicrobial molecules. There is renewed interest in antimicrobial activities of phytochemicals. Nigeria boasts of a huge heritage of medicinal plants and there is avalanche of researches that have been undertaken to screen antimicrobial activities of these plants. Scientific compilation of these studies could provide useful information on the antimicrobial properties of the plants. This information can be useful in the development of new antimicrobial drugs. This paper reviews antimicrobial researches that have been undertaken on Nigerian medicinal plants. PMID:28512606

Antimicrobial activity of Eucalyptus camaldulensis essential oils and their interactions with conventional antimicrobial agents against multi-drug resistant Acinetobacter baumannii.

Science.gov (United States)

Knezevic, Petar; Aleksic, Verica; Simin, Natasa; Svircev, Emilija; Petrovic, Aleksandra; Mimica-Dukic, Neda

2016-02-03

Traditional herbal medicine has become an important issue on the global scale during the past decade. Among drugs of natural origin, special place belongs to essential oils, known as strong antimicrobial agents that can be used to combat antibiotic-resistant bacteria. Eucalyptus camaldulensis leaves are traditional herbal remedy used for various purposes, including treatment of infections. The aim of this study was to determine antimicrobial potential of two E. camaldulensis essential oils against multi-drug resistant (MDR) Acinetobacter baumannii wound isolates and to examine possible interactions of essential oils with conventional antimicrobial agents. Chemical composition of essential oils was determined by gas chromatography-mass spectrometry analysis (GC-MS). MIC values of essential oils against A. baumannii strains were estimated by modified broth microdilution method. The components responsible for antimicrobial activity were detected by bioautographic analysis. The potential synergy between the essential oils and antibiotics (ciprofloxacin, gentamicin and polymyxin B) was examined by checkerboard method and time kill curve. The dominant components of both essential oils were spatulenol, cryptone, p-cimene, 1,8-cineole, terpinen-4-ol and β-pinene. The detected MICs for the E. camaldulensis essential oils were in range from 0.5 to 2 μl mL(-1). The bioautographic assay confirmed antibacterial activity of polar terpene compounds. In combination with conventional antibiotics (ciprofloxacin, gentamicin and polymyxin B), the examined essential oils showed synergistic antibacterial effect in most of the cases, while in some even re-sensitized MDR A. baumannii strains. The synergistic interaction was confirmed by time-kill curves for E. camaldulensis essential oil and polymyxin B combination which reduced bacterial count under detection limit very fast, i.e. after 6h of incubation. The detected anti-A. baumannii activity of E. camaldulensis essential oils

General principles of antimicrobial therapy.

Science.gov (United States)

Leekha, Surbhi; Terrell, Christine L; Edson, Randall S

2011-02-01

Antimicrobial agents are some of the most widely, and often injudiciously, used therapeutic drugs worldwide. Important considerations when prescribing antimicrobial therapy include obtaining an accurate diagnosis of infection; understanding the difference between empiric and definitive therapy; identifying opportunities to switch to narrow-spectrum, cost-effective oral agents for the shortest duration necessary; understanding drug characteristics that are peculiar to antimicrobial agents (such as pharmacodynamics and efficacy at the site of infection); accounting for host characteristics that influence antimicrobial activity; and in turn, recognizing the adverse effects of antimicrobial agents on the host. It is also important to understand the importance of antimicrobial stewardship, to know when to consult infectious disease specialists for guidance, and to be able to identify situations when antimicrobial therapy is not needed. By following these general principles, all practicing physicians should be able to use antimicrobial agents in a responsible manner that benefits both the individual patient and the community.

Animation of Antimicrobial Resistance

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Full Text Available ... search Popular ... produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will ...

[Markers of antimicrobial drug resistance in the most common bacteria of normal facultative anaerobic intestinal flora].

Science.gov (United States)

Plavsić, Teodora

2011-01-01

Bacteria of normal intestinal flora are frequent carriers of markers of antimicrobial drug resistance. Resistance genes may be exchanged with other bacteria of normal flora as well as with pathogenic bacteria. The increase in the number of markers of resistance is one of the major global health problems, which induces the emergence of multi-resistant strains. The aim of this study is to confirm the presence of markers of resistance in bacteria of normal facultative anaerobic intestinal flora in our region. The experiment included a hundred fecal specimens obtained from a hundred healthy donors. A hundred bacterial strains were isolated (the most numerous representatives of the normal facultative-anaerobic intestinal flora) by standard bacteriological methods. The bacteria were cultivated on Endo agar and SS agar for 24 hours at 37 degrees C. Having been incubated, the selected characteristic colonies were submitted to the biochemical analysis. The susceptibility to antimicrobial drugs was tested by standard disc diffusion method, and the results were interpreted according to the Standard of Clinical and Laboratory Standards Institute 2010. The marker of resistance were found in 42% of the isolated bacteria. The resistance was the most common to ampicillin (42% of isolates), amoxicillin with clavulanic acid (14% of isolates), cephalexin (14%) and cotrimoxazole (8%). The finding of 12 multiresistant strains (12% of isolates) and resistance to ciprofloxacin were significant. The frequency of resistance markers was statistically higher in Klebsiella pneumoniae compared to Escherichia coli of normal flora. The finding of a large number of markers of antimicrobial drug resistance among bacteria of normal intestinal flora shows that it is necessary to begin with systematic monitoring of their antimicrobial resistance because it is an indicator of resistance in the population.

Drug Susceptibility Testing of 31 Antimicrobial Agents on Rapidly Growing Mycobacteria Isolates from China.

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Pang, Hui; Li, Guilian; Zhao, Xiuqin; Liu, Haican; Wan, Kanglin; Yu, Ping

2015-01-01

Several species of rapidly growing mycobacteria (RGM) are now recognized as human pathogens. However, limited data on effective drug treatments against these organisms exists. Here, we describe the species distribution and drug susceptibility profiles of RGM clinical isolates collected from four southern Chinese provinces from January 2005 to December 2012. Clinical isolates (73) were subjected to in vitro testing with 31 antimicrobial agents using the cation-adjusted Mueller-Hinton broth microdilution method. The isolates included 55 M. abscessus, 11 M. fortuitum, 3 M. chelonae, 2 M. neoaurum, and 2 M. septicum isolates. M. abscessus (75.34%) and M. fortuitum (15.07%), the most common species, exhibited greater antibiotic resistance than the other three species. The isolates had low resistance to amikacin, linezolid, and tigecycline, and high resistance to first-line antituberculous agents, amoxicillin-clavulanic acid, rifapentine, dapsone, thioacetazone, and pasiniazid. M. abscessus and M. fortuitum were highly resistant to ofloxacin and rifabutin, respectively. The isolates showed moderate resistance to the other antimicrobial agents. Our results suggest that tigecycline, linezolid, clofazimine, and cefmetazole are appropriate choices for M. abscessus infections. Capreomycin, sulfamethoxazole, tigecycline, clofazimine, and cefmetazole are potentially good choices for M. fortuitum infections. Our drug susceptibility data should be useful to clinicians.

Drug Susceptibility Testing of 31 Antimicrobial Agents on Rapidly Growing Mycobacteria Isolates from China

Directory of Open Access Journals (Sweden)

Hui Pang

2015-01-01

Full Text Available Objectives. Several species of rapidly growing mycobacteria (RGM are now recognized as human pathogens. However, limited data on effective drug treatments against these organisms exists. Here, we describe the species distribution and drug susceptibility profiles of RGM clinical isolates collected from four southern Chinese provinces from January 2005 to December 2012. Methods. Clinical isolates (73 were subjected to in vitro testing with 31 antimicrobial agents using the cation-adjusted Mueller-Hinton broth microdilution method. The isolates included 55 M. abscessus, 11 M. fortuitum, 3 M. chelonae, 2 M. neoaurum, and 2 M. septicum isolates. Results. M. abscessus (75.34% and M. fortuitum (15.07%, the most common species, exhibited greater antibiotic resistance than the other three species. The isolates had low resistance to amikacin, linezolid, and tigecycline, and high resistance to first-line antituberculous agents, amoxicillin-clavulanic acid, rifapentine, dapsone, thioacetazone, and pasiniazid. M. abscessus and M. fortuitum were highly resistant to ofloxacin and rifabutin, respectively. The isolates showed moderate resistance to the other antimicrobial agents. Conclusions. Our results suggest that tigecycline, linezolid, clofazimine, and cefmetazole are appropriate choices for M. abscessus infections. Capreomycin, sulfamethoxazole, tigecycline, clofazimine, and cefmetazole are potentially good choices for M. fortuitum infections. Our drug susceptibility data should be useful to clinicians.

Antimicrobial drug resistance evaluations and monitoring in Escherichia coli isolated from poultry environment at different time intervals

International Nuclear Information System (INIS)

Anwar, R.; Khan, M.A.

2004-01-01

A high prevalence of multiple drug resistance was observed in population of E. coli isolated in 1992-93 from poultry carcasses, fluff, hatchery environment and water at different broiler farms in Karachi, Pakistan. Five hundred isolate of E. coli were made of which 375 were tested for their sensitivity of five antimicrobials using the tube dilution method. Similarly, during 1995-1996, 430 E. coli isolates were made (from the same farms) of which 315 were tested for their sensitivity to the same antimicrobials studied in 1992-93. E. coli isolates during 1992-93 and 1995-96 showed increase in resistance from 50 to 56% against amoxicillin, from 62 to 71% against neomycin, from 97 to 100% against oxytetracycline, from 95 to 100% against tetracycline and from 95 to 98% against trimethoprim. It appears that exposure of E. coli of poultry origin in Pakistan to the five studies antimicrobials could well be the cause of increasing antimicrobials resistance. This data supports the growing contention that subtherapeutic doses of antimicrobials should be eliminated as a means of promoting rapid growth. (author)

Antimicrobial drug resistance evaluations and monitoring in Escherichia coli isolated from poultry environment at different time intervals

Energy Technology Data Exchange (ETDEWEB)

Anwar, R; Khan, M A [University of Karachi (Pakistan). Inst. of Environmental Studies

2004-06-01

A high prevalence of multiple drug resistance was observed in population of E. coli isolated in 1992-93 from poultry carcasses, fluff, hatchery environment and water at different broiler farms in Karachi, Pakistan. Five hundred isolate of E. coli were made of which 375 were tested for their sensitivity of five antimicrobials using the tube dilution method. Similarly, during 1995-1996, 430 E. coli isolates were made (from the same farms) of which 315 were tested for their sensitivity to the same antimicrobials studied in 1992-93. E. coli isolates during 1992-93 and 1995-96 showed increase in resistance from 50 to 56% against amoxicillin, from 62 to 71% against neomycin, from 97 to 100% against oxytetracycline, from 95 to 100% against tetracycline and from 95 to 98% against trimethoprim. It appears that exposure of E. coli of poultry origin in Pakistan to the five studies antimicrobials could well be the cause of increasing antimicrobials resistance. This data supports the growing contention that subtherapeutic doses of antimicrobials should be eliminated as a means of promoting rapid growth. (author)

Activities and influence of veterinary drug marketers on antimicrobial usage in livestock production in Oyo and Kaduna States, Nigeria

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Olufemi Ernest Ojo

2017-09-01

Full Text Available Antimicrobial usage in animals contributes to the emergence of antimicrobial resistant bacterial strains. Investigations were carried out on how the characteristics, knowledge, attitude and practices of antimicrobial marketers influenced antimicrobials usage in animal production in Oyo and Kaduna States, Nigeria. Focus group discussions, in-depth interviews and structured questionnaires were used to gather information about the characteristics and activities of antimicrobial marketers. Overall, 70 (56.9 % of 123 marketers had post-secondary education while 76 (61.8 % were trained on the use of antimicrobials. Eighteen (14.6 % of the marketers were licensed veterinarians. Only 51 (41.5 % marketers displayed adequate knowledge about antimicrobials and antimicrobial usage. Sixty-seven (54.6 % marketers requested a prescription before selling antimicrobials while 113 (91.9 % marketer recommended antimicrobials for use in animals. Two-third of the marketers (66.7 % prescribed antimicrobials without physically examining sick animals but based their prescriptions on verbal reports of clinical signs by farmers and on their personal experience. Marketers with higher educational qualification displayed more adequate knowledge of antimicrobials and antimicrobial usage than those with basic education background only. More years of experience in antimicrobial marketing did not translate to better knowledge on antimicrobial usage. Only 45 (36.6 % respondents were aware of the existence of regulatory agencies monitoring the use of antimicrobials in animals. Farmers ignored the services of veterinarians in the diagnosis and control of animal diseases but resorted to drug marketers for help. Effective communication of existing legislations on antimicrobial usage, improved access to veterinary services and strict enforcement of regulatory policies are recommended for checking non-judicious use of antimicrobial agents in animal production. Sales of

Antimicrobial use on Canadian dairy farms.

Science.gov (United States)

Saini, V; McClure, J T; Léger, D; Dufour, S; Sheldon, A G; Scholl, D T; Barkema, H W

2012-03-01

Antimicrobial use (AMU) data are critical for formulating policies for containing antimicrobial resistance. The present study determined AMU on Canadian dairy farms and characterized variation in AMU based on herd-level factors such as milk production, somatic cell count, herd size, geographic region and housing type. Drug use data were collected on 89 dairy herds in 4 regions of Canada, Alberta, Ontario, Québec, and the Maritime provinces (Prince Edward Island, New Brunswick, and Nova Scotia) for an average of 540 d per herd. Dairy producers and farm personnel were asked to deposit empty drug containers into specially provided receptacles. Antimicrobial use was measured as antimicrobial drug use rate (ADUR), with the unit being number of animal defined-daily doses (ADD)/1,000 cow-days. Antimicrobial drug use rates were determined at farm, region, and national level. Combined ADUR of all antimicrobial classes was 14.35 ADD/1,000 cow-days nationally. National level ADUR of the 6 most commonly used antimicrobial drug classes, cephalosporins, penicillins, penicillin combinations, tetracyclines, trimethoprim-sulfonamide combinations, and lincosamides were 3.05, 2.56, 2.20, 1.83, 0.87, and 0.84 ADD/1,000 cow-days, respectively. Dairy herds in Ontario were higher users of third-generation cephalosporins (ceftiofur) than in Québec. Alberta dairy herds were higher users of tetracyclines in comparison to Maritimes. Antimicrobial drug use rate was higher via systemic route as compared with intramammary and other routes of administration (topical, oral, and intrauterine). The ADUR of antimicrobials used intramammarily was higher for clinical mastitis treatment than dry cow therapy. For dry cow therapy, penicillin ADUR was greater than ADUR of first-generation cephalosporins. For clinical mastitis treatment, ADUR of intramammary penicillin combinations was greater than ADUR of cephapirin. Herd-level milk production was positively associated with overall ADUR, ADUR of

Animation of Antimicrobial Resistance

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Full Text Available ... Skip to common links HHS U.S. Department of Health and Human Services U.S. Food and Drug Administration ... Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet ...

Alternative Antimicrobial Approach: Nano-Antimicrobial Materials

Directory of Open Access Journals (Sweden)

Nurit Beyth

2015-01-01

Full Text Available Despite numerous existing potent antibiotics and other antimicrobial means, bacterial infections are still a major cause of morbidity and mortality. Moreover, the need to develop additional bactericidal means has significantly increased due to the growing concern regarding multidrug-resistant bacterial strains and biofilm associated infections. Consequently, attention has been especially devoted to new and emerging nanoparticle-based materials in the field of antimicrobial chemotherapy. The present review discusses the activities of nanoparticles as an antimicrobial means, their mode of action, nanoparticle effect on drug-resistant bacteria, and the risks attendant on their use as antibacterial agents. Factors contributing to nanoparticle performance in the clinical setting, their unique properties, and mechanism of action as antibacterial agents are discussed in detail.

21 CFR 866.1620 - Antimicrobial susceptibility test disc.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Antimicrobial susceptibility test disc. 866.1620 Section 866.1620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Diagnostic Devices § 866.1620 Antimicrobial...

Danish integrated antimicrobial in resistance monitoring and research program

DEFF Research Database (Denmark)

Hammerum, Anette Marie; Heuer, Ole Eske; Emborg, Hanne-Dorthe

2007-01-01

a systematic and continuous monitoring program of antimicrobial drug consumption and antimicrobial agent resistance in animals, food, and humans, the Danish Integrated Antimicrobial Resistance Monitoring and Research Program (DANMAP). Monitoring of antimicrobial drug resistance and a range of research......Resistance to antimicrobial agents is an emerging problem worldwide. Awareness of the undesirable consequences of its widespread occurrence has led to the initiation of antimicrobial agent resistance monitoring programs in several countries. In 1995, Denmark was the first country to establish...... activities related to DANMAP have contributed to restrictions or bans of use of several antimicrobial agents in food animals in Denmark and other European Union countries....

Microbiological aspects of the effectiveness of antimicrobial drugs

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Oleksandr Nazarchuk

2015-06-01

  Abstract Introduction. It is well known, that patients with deep burns belong to the category of critically ill ones. According to the data of National Nosocomial Infections Surveillance (2004, Staphylococcus spp. are among leading opportunistic pathogens of infectious complications in such patients. Nowadays much attention is given to the problem of antibiotic resistance of Staphylococcus clinical strains. More often antiseptics are used in treatment of infectious complications, caused by antibiotic resistant miсroorganisms. The aim of the research was to study microbiological aspects of the effectiveness of antimicrobial drugs. Materials and methods. There were examined 372 critically ill patients with burns, having infectious complications. In all patients microbiological examinations were carried out during the first 7 days after burn trauma. There were isolated 115 clinical strains of Staphylococcus spp.. Their morphological, cultural, biochemical qualities and sensitivity to antibiotics, antiseptics were studied. Rresults of the study. We found, that clinical strains of S. aureus, S. epidermidis were highly resistant to oxacillin (46,9; 59,1 % respectively; were insensitive to clavulanate and sulbactam potentiated beta-lactams; ceftriaxone; meropenem, imipenem; ciprofloxacin. Sensitivity of Staphylococcus to amikacin, linezolid, vancomycin was found. There was shown the sensitivity of antibiotic resistant strains of Staphylococcus to decamethoxin, its polymer composition, chlorhexidine digluconate. In the research there was proved the decreasing of the effectiveness of chlorhexidine digluconate against Staphylococcus in conditions of increasing microbial load to 109 CFU/ml in 6,6 times comparably to decamethoxin drugs (p<0,001. Conclusions Resistant to the majority of antibiotics strains of Staphylococcus spp. store their high sensitivity to antiseptic decamethoxin and its polymeric composition, chlorhexidine digluconate. Microbial load increase up to 109

Antibiotic and Antimicrobial Resistance: Threat Report 2013

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... Form Controls Cancel Submit Search The CDC Antibiotic / Antimicrobial Resistance Note: Javascript is disabled or is not ... please visit this page: About CDC.gov . Antibiotic / Antimicrobial Resistance About Antimicrobial Resistance Biggest Threats Emerging Drug ...

Comparison of treatment records and inventory of empty drug containers to quantify antimicrobial usage in dairy herds.

Science.gov (United States)

Nobrega, Diego B; De Buck, Jeroen; Naqvi, S Ali; Liu, Gang; Naushad, Sohail; Saini, Vineet; Barkema, Herman W

2017-12-01

Assessment of antimicrobial use (AMU) is vital for interpreting the origin of changes in antimicrobial resistance (AMR). The objectives of the present study were to estimate the association between AMU determined using on-farm treatment records (TR) and inventory of empty drug containers (INV). Herds were selected to represent Canadian dairy farms. Producers were asked to record animal health events and treatments on a standard General Health Event form. For inventory data, 40-L receptacles were placed at various locations considered convenient to deposit all empty drug containers. Antimicrobial defined-daily dosages (ADD) were calculated for 51 Canadian herds using the 2 methods. Estimation of AMU was 31,840 ADD using the INV and 14,487 ADD using the TR, indicating that for every TR entry, 2.20 times more treatments were observed using the INV. Mastitis, reproductive conditions, and dry cow therapy were the most frequent reasons for antimicrobial therapy when assessing TR. For all antimicrobials evaluated, mean ADD was higher using the INV versus TR. Regardless, a strong positive correlation (0.80) was observed between the 2 methods, indicating that herds with increased number of ADD recorded using the INV also had increased number of ADD recorded using TR. Furthermore, a positive association was observed for the 6 most commonly used antimicrobials. In comparison to methods used in surveillance programs on AMU in livestock that assume a constant use in all herds (i.e., sales data), INV provided a herd-level specific quantity of AMU positively correlated with AMU recorded at the animal level in general. The INV was easy to implement and provided a measure of total AMU in the herd. Availability of such information would be valuable for interpreting changes in AMR at the herd level and enabling evaluation of interventions for decreasing AMR. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Enhancement of host defense against pathogens by antimicrobial peptides : a new approach to combat microbial drug resistance

NARCIS (Netherlands)

Does, Anne Margaretha van der

2011-01-01

Due to their abilities to eliminate pathogens and modulate host’s immune responses, antimicrobial peptides are considered as potential alternatives for the treatment of infections with (multi-drug resistant) pathogens. In this thesis the immunomodulatory actions of two peptides have been

Use of antimicrobial drugs in general hospitals. I. Description of population and definition of methods.

Science.gov (United States)

Townsend, T R; Shapiro, M; Rosner, B; Kass, E H

1979-06-01

The patterns of use of antimicrobial drugs in a random sample of general hosptials in Pennsylvania were studied. The sample was tested for validity, and all deaths and discharges were analyzed for 10 random days drawn across the year spanning July 1973 to June 1974. Methods were developed for abstracting the hospital records and for determining the reproducibility of the findings of the physician and nonphysician chart reviewers. More than 99% of the requested charts were available. In the 5,288 charts reviewed, most of the required data were readily available. The study population was 84% white and 58% female; most patients were in hospitals that had more than 300 beds and that were located in towns with populations of greater than 10,000. In 41% of the 2,070 antimicrobial courses administered to almost 30% of the patients, an explicit clinical statement of why the drug was being given could be found in the chart. The information for review was found in clinical charts, but in half of the charts, the information required was not on face sheets and discharge summaries.

National Antimicrobial Resistance Monitoring System: Two Decades of Advancing Public Health Through Integrated Surveillance of Antimicrobial Resistance.

Science.gov (United States)

Karp, Beth E; Tate, Heather; Plumblee, Jodie R; Dessai, Uday; Whichard, Jean M; Thacker, Eileen L; Hale, Kis Robertson; Wilson, Wanda; Friedman, Cindy R; Griffin, Patricia M; McDermott, Patrick F

2017-10-01

Drug-resistant bacterial infections pose a serious and growing public health threat globally. In this review, we describe the role of the National Antimicrobial Resistance Monitoring System (NARMS) in providing data that help address the resistance problem and show how such a program can have broad positive impacts on public health. NARMS was formed two decades ago to help assess the consequences to human health arising from the use of antimicrobial drugs in food animal production in the United States. A collaboration among the Centers for Disease Control and Prevention, the U.S. Food and Drug Administration, the United States Department of Agriculture, and state and local health departments, NARMS uses an integrated "One Health" approach to monitor antimicrobial resistance in enteric bacteria from humans, retail meat, and food animals. NARMS has adapted to changing needs and threats by expanding surveillance catchment areas, examining new isolate sources, adding bacteria, adjusting sampling schemes, and modifying antimicrobial agents tested. NARMS data are not only essential for ensuring that antimicrobial drugs approved for food animals are used in ways that are safe for human health but they also help address broader food safety priorities. NARMS surveillance, applied research studies, and outbreak isolate testing provide data on the emergence of drug-resistant enteric bacteria; genetic mechanisms underlying resistance; movement of bacterial populations among humans, food, and food animals; and sources and outcomes of resistant and susceptible infections. These data can be used to guide and evaluate the impact of science-based policies, regulatory actions, antimicrobial stewardship initiatives, and other public health efforts aimed at preserving drug effectiveness, improving patient outcomes, and preventing infections. Many improvements have been made to NARMS over time and the program will continue to adapt to address emerging resistance threats, changes in

Animation of Antimicrobial Resistance

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Full Text Available ... menu Skip to common links HHS U.S. Department of Health and Human Services U.S. Food and Drug Administration ... Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More ...

Antimicrobial Drug Resistance and Gonorrhea

Centers for Disease Control (CDC) Podcasts

2017-12-26

Dr. Robert Kirkcaldy, a medical officer at CDC, discusses his article on antimicrobial resistance and gonorrhea.  Created: 12/26/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 12/26/2017.

Antimicrobial Resistance of Faecal Escherichia coli Isolates from Pig Farms with Different Durations of In-feed Antimicrobial Use.

Science.gov (United States)

Gibbons, J F; Boland, F; Egan, J; Fanning, S; Markey, B K; Leonard, F C

2016-05-01

Antimicrobial use and resistance in animal and food production are of concern to public health. The primary aims of this study were to determine the frequency of resistance to 12 antimicrobials in Escherichia coli isolates from 39 pig farms and to identify patterns of antimicrobial use on these farms. Further aims were to determine whether a categorization of farms based on the duration of in-feed antimicrobial use (long-term versus short-term) could predict the occurrence of resistance on these farms and to identify the usage of specific antimicrobial drugs associated with the occurrence of resistance. Escherichia coli were isolated from all production stages on these farms; susceptibility testing was carried out against a panel of antimicrobials. Antimicrobial prescribing data were collected, and farms were categorized as long term or short term based on these. Resistance frequencies and antimicrobial use were tabulated. Logistic regression models of resistance to each antimicrobial were constructed with stage of production, duration of antimicrobial use and the use of 5 antimicrobial classes included as explanatory variables in each model. The greatest frequencies of resistance were observed to tetracycline, trimethoprim/sulphamethoxazole and streptomycin with the highest levels of resistance observed in isolates from first-stage weaned pigs. Differences in the types of antimicrobial drugs used were noted between long-term and short-term use farms. Categorization of farms as long- or short-term use was sufficient to predict the likely occurrence of resistance to 3 antimicrobial classes and could provide an aid in the control of resistance in the food chain. Stage of production was a significant predictor variable in all models of resistance constructed and did not solely reflect antimicrobial use at each stage. Cross-selection and co-selection for resistance was evident in the models constructed, and the use of trimethoprim/sulphonamide drugs in particular was

Pharmacy intervention on antimicrobial management of critically ill patients

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Ijo I

2011-06-01

Full Text Available Frequent, suboptimal use of antimicrobial drugs has resulted in the emergence of microbial resistance, compromised clinical outcomes and increased costs, particularly in the intensive care unit (ICU. Mounting on these challenges is the paucity of new antimicrobial agents.Objectives: The study aims to determine the impact of prospective pharmacy-driven antimicrobial stewardship in the ICU on clinical and potential financial outcomes. The primary objectives were to determine the mean length of stay (LOS and mortality rate in the ICU resulting from prospective pharmacy interventions on antimicrobial therapy. The secondary objective was to calculate the difference in total drug acquisition costs resulting from pharmacy infectious diseases (ID-related interventions.Methods: In collaboration with an infectious disease physician, the ICU pharmacy team provided prospective audit with feedback to physicians on antimicrobial therapies of 70 patients over a 4-month period in a 31-bed ICU. In comparison with published data, LOS and mortality of pharmacy-monitored ICU patients were recorded. Daily cost savings on antimicrobial drugs and charges for medication therapy management (MTM services were added to calculate potential total cost savings. Pharmacy interventions focused on streamlining, dose optimization, intravenous-to-oral conversion, antimicrobial discontinuation, new recommendation and drug information consult. Antimicrobial education was featured in oral presentations and electronic newsletters for pharmacists and clinicians.Results: The mean LOS in the ICU was 6 days, which was lower than the published reports of LOS ranging from 11 to 36 days. The morality rate of 14% was comparable to the reported range of 6 to 20% in published literature. The total drug cost difference was a negative financial outcome or loss of USD192 associated with ID-related interventions.Conclusion: In collaboration with the infectious disease physician, prospective

Animation of Antimicrobial Resistance

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Full Text Available ... Skip to common links HHS U.S. Department of Health and Human Services U.S. Food and Drug Administration A to Z Index Follow FDA En Español Search FDA Submit search ... & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet ...

Multiclass method for the quantification of 92 veterinary antimicrobial drugs in livestock excreta, wastewater, and surface water by liquid chromatography with tandem mass spectrometry.

Science.gov (United States)

Gao, Jinfang; Cui, Yonghui; Tao, Yanfei; Huang, Lingli; Peng, Dapeng; Xie, Shuyu; Wang, Xu; Liu, Zhenli; Chen, Dongmei; Yuan, Zonghui

2016-11-01

A simple multiresidue method was developed for detecting and quantifying 92 veterinary antimicrobial drugs from eight classes (β-lactams, quinolones, sulfonamides, tetracyclines, lincomycins, macrolides, chloramphenicols, and pleuromutilin) in livestock excreta and water by liquid chromatography with tandem mass spectrometry. The feces samples were extracted by ultrasound-assisted extraction with a mixture of acetonitrile/water (80:20, v/v) and edetate disodium, followed by a cleanup using solid-phase extraction with an amino cartridge. Water samples were purified with hydrophilic-lipophilic balance solid-phase extraction column. Urine samples were extracted with acetonitrile and edetate disodium. Detection of veterinary antimicrobial drugs was achieved by liquid chromatography with tandem mass spectrometry using both positive and negative electrospray ionization mode. The recovery values of veterinary antimicrobial drugs in feces, urine, and water samples were 75-99, 85-110, and 85-101% and associated relative standard deviations were less than 15, 10, and 8%, respectively. The limits of quantification in feces, urine, and water samples were 0.5-1, 0.5-1, and 0.01-0.05 μg/L, respectively. This method was applied to determine real samples obtained from local farms and provides reliable quantification and identification results of 92 veterinary antimicrobial drugs in livestock excreta and water. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Antimicrobial activity of PVP from an Antarctic bacterium, Janthinobacterium sp. Ant5-2, on multi-drug and methicillin resistant Staphylococcus aureus

KAUST Repository

Huang, Jonathan P.

2012-04-11

Multiple drug resistant (MDR) and methicillin-resistant Staphylococcus aureus (MRSA) have become increasingly prevalent as a community acquired infection. As a result limited treatment options are available with conventional synthetic antibiotics. Bioprospecting natural products with potent antimicrobial activity show promise for developing new drugs against this pathogen. In this study, we have investigated the antimicrobial activity of a purple violet pigment (PVP) from an Antarctic bacterium, Janthinobacterium sp. Ant5-2 on 15 clinical MDR and MRSA strains. The colorimetric resazurin assay was employed to determine the minimum inhibitory concentration (MIC90) of PVP against MDR and MRSA. The MIC90 ranged between 1.57 µg/mL and 3.13 µg/mL, which are significantly lower than many antimicrobials tested from natural sources against this pathogen. The spectrophotometrically determined growth analysis and total microscopic counts using Live/dead® BacLight™ fluorescent stain exhibited a steady decrease in viability of both MDR and MRSA cultures following treatment with PVP at the MIC levels. In silico predictive molecular docking study revealed that PVP could be a DNA-targeting minor groove binding antimicrobial compound. The continued development of novel antimicrobials derived from natural sources with the combination of a suite of conventional antibiotics could stem the rising pandemic of MDR and MRSA along with other deadly microbial pathogens.

Antimicrobial activity of PVP from an Antarctic bacterium, Janthinobacterium sp. Ant5-2, on multi-drug and methicillin resistant Staphylococcus aureus

KAUST Repository

Huang, Jonathan P.; Mojib, Nazia; Goli, Rakesh R.; Watkins, Samantha; Waites, Ken B.; Ravindra, Rasik; Andersen, Dale T.; Bej, Asim K.

2012-01-01

Multiple drug resistant (MDR) and methicillin-resistant Staphylococcus aureus (MRSA) have become increasingly prevalent as a community acquired infection. As a result limited treatment options are available with conventional synthetic antibiotics. Bioprospecting natural products with potent antimicrobial activity show promise for developing new drugs against this pathogen. In this study, we have investigated the antimicrobial activity of a purple violet pigment (PVP) from an Antarctic bacterium, Janthinobacterium sp. Ant5-2 on 15 clinical MDR and MRSA strains. The colorimetric resazurin assay was employed to determine the minimum inhibitory concentration (MIC90) of PVP against MDR and MRSA. The MIC90 ranged between 1.57 µg/mL and 3.13 µg/mL, which are significantly lower than many antimicrobials tested from natural sources against this pathogen. The spectrophotometrically determined growth analysis and total microscopic counts using Live/dead® BacLight™ fluorescent stain exhibited a steady decrease in viability of both MDR and MRSA cultures following treatment with PVP at the MIC levels. In silico predictive molecular docking study revealed that PVP could be a DNA-targeting minor groove binding antimicrobial compound. The continued development of novel antimicrobials derived from natural sources with the combination of a suite of conventional antibiotics could stem the rising pandemic of MDR and MRSA along with other deadly microbial pathogens.

In vitro evaluation of antimicrobial features of vasopressors

Directory of Open Access Journals (Sweden)

Habib Bostan

2014-03-01

Full Text Available Background: Drugs administered as intravenous infusion may be contaminated during several stages of production or preparation. However studies focusing on antibacterial effects of vasopressor drugs are very rare. This study investigates the in vitro antimicrobial activity of the clinically used forms of vasopressors. Materials and methods: In vitro antimicrobial activities of vasopressor drugs of different concentrations were investigated by using the micro dilution technique. Microorganisms used in the test were Escherichia coli ATCC 25922, Yersinia pseudotuberculosis ATCC 911, Pseudomonas aeruginosa ATCC 10145, Listeria monocytogenes ATCC 43251, Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, Bacillus cereus 702 Roma, Mycobacterium smegmatis ATCC607, Candida albicans ATCC 60193, and Saccharomyces cerevisiae RSKK 251. Antibacterial assays were performed in Mueller-Hinton broth at pH 7.3 and antifungal assays were performed in buffered Yeast Nitrogen Base at pH 7.0. Results: Two different dopamine preparations showed antimicrobial activity. No other study drug showed any antimicrobial activity. Conclusions: In our opinion, dopamine's antibacterial effects may be advantageous for inhibiting the spread of bacterial contamination during the preparation of the infusion solutions. However, it is important that strict guidelines regarding the need for sterile equipment and deliverables be adhered to during all procedures performed in the intensive care units. Keywords: Antimicrobial activities, Vasopressor drugs, Drug contamination

Antimicrobial Peptides: A Promising Therapeutic Strategy in Tackling Antimicrobial Resistance.

Science.gov (United States)

Nuti, Ramya; Goud, Nerella S; Saraswati, A Prasanth; Alvala, Ravi; Alvala, Mallika

2017-01-01

Antimicrobial resistance (AMR) has posed a serious threat to global public health and it requires immediate action, preferably long term. Current drug therapies have failed to curb this menace due to the ability of microbes to circumvent the mechanisms through which the drugs act. From the drug discovery point of view, the majority of drugs currently employed for antimicrobial therapy are small molecules. Recent trends reveal a surge in the use of peptides as drug candidates as they offer remarkable advantages over small molecules. Newer synthetic strategies like organometalic complexes, Peptide-polymer conjugates, solid phase, liquid phase and recombinant DNA technology encouraging the use of peptides as therapeutic agents with a host of chemical functions, and tailored for specific applications. In the last decade, many peptide based drugs have been successfully approved by the Food and Drug Administration (FDA). This success can be attributed to their high specificity, selectivity and efficacy, high penetrability into the tissues, less immunogenicity and less tissue accumulation. Considering the enormity of AMR, the use of Antimicrobial Peptides (AMPs) can be a viable alternative to current therapeutics strategies. AMPs are naturally abundant allowing synthetic chemists to develop semi-synthetics peptide molecules. AMPs have a broad spectrum of activity towards microbes and they possess the ability to bypass the resistance induction mechanisms of microbes. The present review focuses on the potential applications of AMPs against various microbial disorders and their future prospects. Several resistance mechanisms and their strategies have also been discussed to highlight the importance in the current scenario. Breakthroughs in AMP designing, peptide synthesis and biotechnology have shown promise in tackling this challenge and has revived the interest of using AMPs as an important weapon in fighting AMR. Copyright© Bentham Science Publishers; For any queries

Workshop report: the 2012 antimicrobial agents in veterinary medicine: exploring the consequences of antimicrobial drug use: a 3-D approach.

Science.gov (United States)

Martinez, M; Blondeau, J; Cerniglia, C E; Fink-Gremmels, J; Guenther, S; Hunter, R P; Li, X-Z; Papich, M; Silley, P; Soback, S; Toutain, P-L; Zhang, Q

2014-02-01

Antimicrobial resistance is a global challenge that impacts both human and veterinary health care. The resilience of microbes is reflected in their ability to adapt and survive in spite of our best efforts to constrain their infectious capabilities. As science advances, many of the mechanisms for microbial survival and resistance element transfer have been identified. During the 2012 meeting of Antimicrobial Agents in Veterinary Medicine (AAVM), experts provided insights on such issues as use vs. resistance, the available tools for supporting appropriate drug use, the importance of meeting the therapeutic needs within the domestic animal health care, and the requirements associated with food safety and food security. This report aims to provide a summary of the presentations and discussions occurring during the 2012 AAVM with the goal of stimulating future discussions and enhancing the opportunity to establish creative and sustainable solutions that will guarantee the availability of an effective therapeutic arsenal for veterinary species. © Published (2014). This article is a U.S. Government work and is in the public domain in the USA.

Mesobuthus Venom-Derived Antimicrobial Peptides Possess Intrinsic Multifunctionality and Differential Potential as Drugs

Directory of Open Access Journals (Sweden)

Bin Gao

2018-02-01

Full Text Available Animal venoms are a mixture of peptides and proteins that serve two basic biological functions: predation and defense against both predators and microbes. Antimicrobial peptides (AMPs are a common component extensively present in various scorpion venoms (herein abbreviated as svAMPs. However, their roles in predation and defense against predators and potential as drugs are poorly understood. Here, we report five new venom peptides with antimicrobial activity from two Mesobuthus scorpion species. These α-helical linear peptides displayed highly bactericidal activity toward all the Gram-positive bacteria used here but differential activity against Gram-negative bacteria and fungi. In addition to the antibiotic activity, these AMPs displayed lethality to houseflies and hemotoxin-like toxicity on mice by causing hemolysis, tissue damage and inducing inflammatory pain. Unlike AMPs from other origins, these venom-derived AMPs seem to be unsuitable as anti-infective drugs due to their high hemolysis and low serum stability. However, MeuTXKβ1, a known two-domain Mesobuthus AMP, is an exception since it exhibits high activity toward antibiotic resistant Staphylococci clinical isolates with low hemolysis and high serum stability. The findings that the classical AMPs play predatory and defensive roles indicate that the multifunctionality of scorpion venom components is an intrinsic feature likely evolved by natural selection from microbes, prey and predators of scorpions. This definitely provides an excellent system in which one can study how a protein adaptively evolves novel functions in a new environment. Meantimes, new strategies are needed to remove the toxicity of svAMPs on eukaryotic cells when they are used as leads for anti-infective drugs.

Antimicrobial drug resistance in Staphylococcus aureus isolated from cattle in Brazil.

Science.gov (United States)

Pereira, M S; Siqueira-Júnior, J P

1995-06-01

Isolates of Staphylococcus aureus obtained from apparently healthy cattle in the State of Paraiba, Brazil were characterized in relation to resistance to 21 antimicrobial agents. Among the 46 isolates obtained, resistance to penicillin was most frequent, followed by resistance to cadmium, streptomycin, arsenate, tetracycline, mercury, erythromycin and kanamycin/neomycin. All isolates were susceptible to fusidic acid, ethidium bromide, cetrimide, chloramphenicol, benzalkonium chloride, doxycycline, gentamicin, methicillin, minocycline, novobiocin, rifamycin, tylosin and vancomycin. Only six isolates were susceptible to all the drugs tested. With respect to the antibiotics, multi-resistant isolates were uncommon. These results are probably a consequence of the peculiarities of local drug usage pressures. In relation to metal ions, resistance to mercury was rare while resistance to arsenate was relatively frequent, which contrasts with the situation for human Staph. aureus strains. After treatment with ethidium bromide, elimination of resistance to penicillin, tetracycline, streptomycin, erythromycin and cadmium was observed, which was consistent with the genetic determinants being plasmid-borne.

Antimicrobial drug use and risk factors associated with treatment incidence and mortality in Swiss veal calves reared under improved welfare conditions.

Science.gov (United States)

Lava, M; Schüpbach-Regula, G; Steiner, A; Meylan, M

2016-04-01

Ninety-one Swiss veal farms producing under a label with improved welfare standards were visited between August and December 2014 to investigate risk factors related to antimicrobial drug use and mortality. All herds consisted of own and purchased calves, with a median of 77.4% of purchased calves. The calves' mean age was 29±15days at purchasing and the fattening period lasted at average 120±28 days. The mean carcass weight was 125±12kg. A mean of 58±33 calves were fattened per farm and year, and purchased calves were bought from a mean of 20±17 farms of origin. Antimicrobial drug treatment incidence was calculated with the defined daily dose methodology. The mean treatment incidence (TIADD) was 21±15 daily doses per calf and year. The mean mortality risk was 4.1%, calves died at a mean age of 94±50 days, and the main causes of death were bovine respiratory disease (BRD, 50%) and gastro-intestinal disease (33%). Two multivariable models were constructed, for antimicrobial drug treatment incidence (53 farms) and mortality (91 farms). No quarantine, shared air space for several groups of calves, and no clinical examination upon arrival at the farm were associated with increased antimicrobial treatment incidence. Maximum group size and weight differences >100kg within a group were associated with increased mortality risk, while vaccination and beef breed were associated with decreased mortality risk. The majority of antimicrobial treatments (84.6%) were given as group treatments with oral powder fed through an automatic milk feeding system. Combination products containing chlortetracycline with tylosin and sulfadimidine or with spiramycin were used for 54.9%, and amoxicillin for 43.7% of the oral group treatments. The main indication for individual treatment was BRD (73%). The mean age at the time of treatment was 51 days, corresponding to an estimated weight of 80-100kg. Individual treatments were mainly applied through injections (88.5%), and included

77 FR 2302 - Agency Information Collection Activities; Proposed Collection; Comment Request; Antimicrobial...

Science.gov (United States)

2012-01-17

...] Agency Information Collection Activities; Proposed Collection; Comment Request; Antimicrobial Animal Drug... distribution reports for antimicrobials in food producing animals. DATES: Submit either electronic or written... techniques, when appropriate, and other forms of information technology. Antimicrobial Animal Drug...

Efflux pumps as antimicrobial resistance mechanisms.

Science.gov (United States)

Poole, Keith

2007-01-01

Antibiotic resistance continues to hamper antimicrobial chemotherapy of infectious disease, and while biocide resistance outside of the laboratory is as yet unrealized, in vitro and in vivo episodes of reduced biocide susceptibility are not uncommon. Efflux mechanisms, both drug-specific and multidrug, are important determinants of intrinsic and/or acquired resistance to these antimicrobials in important human pathogens. Multidrug efflux mechanisms are generally chromosome-encoded, with their expression typically resultant from mutations in regulatory genes, while drug-specific efflux mechanisms are encoded by mobile genetic elements whose acquisition is sufficient for resistance. While it has been suggested that drug-specific efflux systems originated from efflux determinants of self-protection in antibiotic-producing Actinomycetes, chromosomal multidrug efflux determinants, at least in Gram-negative bacteria, are appreciated as having an intended housekeeping function unrelated to drug export and resistance. Thus, it will be important to elucidate the intended natural function of these efflux mechanisms in order, for example, to anticipate environmental conditions or circumstances that might promote their expression and, so, compromise antimicrobial chemotherapy. Given the clinical significance of antimicrobial exporters, it is clear that efflux must be considered in formulating strategies for treatment of drug-resistant infections, both in the development of new agents, for example, less impacted by efflux or in targeting efflux directly with efflux inhibitors.

ANTIMICROBIAL, PHYSICAL AND CHEMICAL QUALITIES OF MEDICINAL ANTISEPTIC DRUGS

Directory of Open Access Journals (Sweden)

Paliy D. V.

2014-12-01

Full Text Available In our research results of the study of antimicrobial, physical and chemical qualities of antiseptic medicines of decamethoxin (DCM. Antimicrobial activity of DCM, palisan, decasan, deseptol against srains of S.aureus (n 56, S.epidermidis (n 26, E.coli (n 24, P.mirabilis (n 11, P.vulgaris (n 8 was studied by means of method of serial dilutions. Obtained data of mass spectrometry study of antimicrobial compositions with constant concentrations of DCM have shown that medicinal forms of DCM are complex physical and chemical systems, because of different origin and number of adjuvant ingredients used during their fabrication. Among synthetic quaternary ammonium agents there have been found the substance (commercial name of medicine is decamethoxin to have high antimicrobial activity against strains of grampositive and gram-negative microorganisms, an also C.albicans. There was found that antimicrobial activity of antiseptic palisan had been higher comparably to DCM in equivalent concentration. The composition and concentrations of acting agents and the methodology of preparation of palisan have been substantiated on the basis of microbiological, mass spectrometry characteristics of antiseptics DCM, palisan.

78 FR 75570 - Guidance for Industry on New Animal Drugs and New Animal Drug Combination Products Administered...

Science.gov (United States)

2013-12-12

... Guidance for Industry (GFI) 209, ``The Judicious Use of Medically Important Antimicrobial Drugs in Food... of certain antimicrobial new animal drug products who are interested in revising conditions of use... Medically Important Antimicrobial Drugs in Food-Producing Animals,'' and to set timelines for stakeholders...

Metabolic network analysis-based identification of antimicrobial drug targets in category A bioterrorism agents.

Directory of Open Access Journals (Sweden)

Yong-Yeol Ahn

Full Text Available The 2001 anthrax mail attacks in the United States demonstrated the potential threat of bioterrorism, hence driving the need to develop sophisticated treatment and diagnostic protocols to counter biological warfare. Here, by performing flux balance analyses on the fully-annotated metabolic networks of multiple, whole genome-sequenced bacterial strains, we have identified a large number of metabolic enzymes as potential drug targets for each of the three Category A-designated bioterrorism agents including Bacillus anthracis, Francisella tularensis and Yersinia pestis. Nine metabolic enzymes- belonging to the coenzyme A, folate, phosphatidyl-ethanolamine and nucleic acid pathways common to all strains across the three distinct genera were identified as targets. Antimicrobial agents against some of these enzymes are available. Thus, a combination of cross species-specific antibiotics and common antimicrobials against shared targets may represent a useful combinatorial therapeutic approach against all Category A bioterrorism agents.

Animation of Antimicrobial Resistance

Medline Plus

Full Text Available ... proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the development of resistant strains ... bacteria, complicating clinician's efforts to select the appropriate ... and human medicine to preserve the effectiveness of these drugs. One ...

77 FR 22327 - Draft Guidance for Industry on New Animal Drugs and New Animal Drug Combination Products...

Science.gov (United States)

2012-04-13

... resistance in human and animal bacterial pathogens when medically important antimicrobial drugs are used in... Judicious Use of Medically Important Antimicrobial Drugs in Food-Producing Animals'' and to set timelines... Judicious Use of Medically Important Antimicrobial Drugs in Food-Producing Animals'' (GFI 209) and (2) the...

Pharmacokinetic-pharmacodynamic (PK-PD) modeling and the rational selection of dosage regimes for the prudent use of antimicrobial drugs.

Science.gov (United States)

Papich, Mark G

2014-07-16

One of the strategies to decrease inappropriate antimicrobial use in veterinary medicine is to apply pharmacokinetic-pharmacodynamic (PK-PD) principles to dosing regimens. If antimicrobials are used appropriately by applying these principles to attain targets for area-under-the-curve to MIC ratio (AUC/MIC), peak concentration to MIC ratio (CMAX/MIC), and time above MIC (T>MIC), more effective antibiotic therapy is possible, thus avoiding ineffective administration. Another mechanism whereby inappropriate antibiotic administration can be avoided is to use accurate Interpretive Criteria established by the Clinical Laboratory Standards Institute (CLSI) for breakpoint selection. Inaccurate breakpoints will encourage antibiotic administration that is likely to be ineffective. For newly approved antimicrobials, three criteria are used for determining breakpoints: PK-PD criteria, MIC distributions, and clinical response. For older (often generic drugs) evaluated by the CLSI, recent clinical data may not be available and breakpoints are derived from PK-PD principles, wild-type distributions, and Monte Carlo simulations. It is the goal of the CLSI subcommittee that these revised breakpoints will encourage more effective antimicrobial use and avoid unnecessary antimicrobial administration. Copyright © 2014 Elsevier B.V. All rights reserved.

Antimicrobial and cell-penetrating properties of penetratin analogs

DEFF Research Database (Denmark)

Bahnsen, Jesper Søborg; Franzyk, Henrik; Sandberg-Schaal, Anne

2013-01-01

Cell-penetrating peptides (CPPs) and antimicrobial peptides (AMPs) show great potential as drug delivery vectors and new antibiotic drug entities, respectively. The current study deals with the properties of a variety of peptide analogs derived from the well-known CPP penetratin as well as octaar......Cell-penetrating peptides (CPPs) and antimicrobial peptides (AMPs) show great potential as drug delivery vectors and new antibiotic drug entities, respectively. The current study deals with the properties of a variety of peptide analogs derived from the well-known CPP penetratin as well...... as octaarginine and different Tat sequences. The effects of peptide length, guanidinium content, and sequence of non-cationic residues were assessed in mammalian and bacterial cells. The arginine (Arg) content in the penetratin analogs was found to influence eukaryotic cell uptake efficiency, antimicrobial...... was similar, the eukaryotic cellular uptake of the shuffled analogs was noticeably lower than for native penetratin. Moreover, a point substitution of Met to Leu in native penetratin had no influence on eukaryotic cellular uptake and antimicrobial effect, and only a minor effect on cytotoxicity, in contrast...

Drug use and antimicrobial resistance among Escherichia coli and Enterococcus spp. isolates from chicken and turkey flocks slaughtered in Quebec, Canada

OpenAIRE

Boulianne, Martine; Arsenault, Julie; Daignault, Danielle; Archambault, Marie; Letellier, Ann; Dutil, Lucie

2016-01-01

An observational study was conducted of chicken and turkey flocks slaughtered at federal processing plants in the province of Quebec, Canada. The objectives were to estimate prevalence of drug use at hatchery and on farm and to identify antimicrobial resistance (AMR) in cecal Escherichia coli and Enterococcus spp. isolates and factors associated with AMR. Eighty-two chicken flocks and 59 turkey flocks were sampled. At the hatchery, the most used antimicrobial was ceftiofur in chickens (76% of...

The Impact of Restricting Over-the-Counter Sales of Antimicrobial Drugs: Preliminary Analysis of National Data.

Science.gov (United States)

Moura, Maria Luísa; Boszczowski, Icaro; Mortari, Naíma; Barrozo, Lígia Vizeu; Chiaravalloti Neto, Francisco; Lobo, Renata Desordi; Pedroso de Lima, Antonio Carlos; Levin, Anna S

2015-09-01

To describe the nationwide impact of a restrictive law on over-the-counter sales of antimicrobial drugs, implemented in Brazil in November 2010. Approximately 75% of the population receives healthcare from the public health system and receives free-of-charge medication if prescribed. Total sales in private pharmacies as compared with other channels of sales of oral antibiotics were evaluated in this observational study before and after the law (2008-2012). Defined daily dose per 1000 inhabitants per day (DDD/TID) was used as standard unit. In private pharmacies the effect of the restrictive law was statistically significant (P sales was observed (P = 0.643). The impact in the South and Southeast (more developed) regions was higher than in the North, Northeast, and Mid-West. The state capitals had a 19% decrease, compared with 0.8% increase in the rest of the states. Before the law, the sales of antimicrobial drugs were steadily increasing. From November 2010, with the restrictive law, there was an abrupt drop in sales followed by an increase albeit at a significantly lower rate. The impact was higher in regions with better socio-economic status.

Modulating the properties of sunflower oil based novel emulgels using castor oil fatty acid ester: prospects for topical antimicrobial drug delivery.

Science.gov (United States)

Behera, B; Biswal, D; Uvanesh, K; Srivastava, A K; Bhattacharya, Mrinal K; Paramanik, K; Pal, K

2015-04-01

The current study describes the effect of polyglycerol polyricinoleate (PGPR) on the properties of sunflower oil and span-40 based emulgels. The prepared emulgels contained PGPR in varied concentrations. The microstructure of the emulgels was characterized by bright-field microscopy. The molecular interactions amongst the components of the emulgels were studied using FTIR spectroscopy. The flow and mechanical behaviors of the emulgels were studied using cone-and-plate viscometer and static mechanical tester, respectively. The efficiency of the metronidazole-loaded emulgels as antimicrobial formulations was tested in vitro. E. coli was used as the model microorganism for the antimicrobial study. The emulgels were also explored for iontophoretic delivery applications. The biocompatibility of the emulgels was tested using human keratinocytes (HaCaT). The microscopic evaluation of the emulgels indicated formation of biphasic formulations. FTIR studies suggested a decrease in the hydrogen bonding amongst the components of the emulgels as the concentration of the PGPR was increased. Viscosity studies indicated shear-thinning property of the emulgels. An increase in the PGPR concentration resulted in the reduction in the mechanical properties of the emulgels. Incorporation of PGPR resulted in the decrease in the drug released (both passive and iontophoresis) from the emulgels. The emulgels were found to be cytocompatible in the presence of keratinocytes. The drug loaded emulgels showed good antimicrobial activity against E. coli. In gist, the developed emulgels can be tried for controlled delivery of antimicrobial drugs. The physical and the release properties of the emulgels can be modulated by incorporating PGPR in varied proportions. Copyright © 2015 Elsevier B.V. All rights reserved.

Delivering precision antimicrobial therapy through closed-loop control systems

Science.gov (United States)

Rawson, T M; O’Hare, D; Herrero, P; Sharma, S; Moore, L S P; de Barra, E; Roberts, J A; Gordon, A C; Hope, W; Georgiou, P; Cass, A E G; Holmes, A H

2018-01-01

Abstract Sub-optimal exposure to antimicrobial therapy is associated with poor patient outcomes and the development of antimicrobial resistance. Mechanisms for optimizing the concentration of a drug within the individual patient are under development. However, several barriers remain in realizing true individualization of therapy. These include problems with plasma drug sampling, availability of appropriate assays, and current mechanisms for dose adjustment. Biosensor technology offers a means of providing real-time monitoring of antimicrobials in a minimally invasive fashion. We report the potential for using microneedle biosensor technology as part of closed-loop control systems for the optimization of antimicrobial therapy in individual patients. PMID:29211877

Veterinary drug usage and antimicrobial resistance in bacteria of animal origin

DEFF Research Database (Denmark)

Aarestrup, Frank Møller

2005-01-01

In the production of food animals, large amounts of antimicrobial agents are used for therapy and prophylaxis of bacterial infections and in feed to promote growth. There are large variations in the amounts of antimicrobial agents used to produce the same amount of meat among the different Europe...... monitoring the occurrence and development of resistance and consumption of antimicrobial agents are strongly desirable, as is research into the most appropriate ways to use antimicrobial agents in veterinary medicine....

Antimicrobial chemotherapy and Sustainable Development: The ...

African Journals Online (AJOL)

Antimicrobial chemotherapy and Sustainable Development: The past, The Current Trend, and the futu. ... Within the past half century, a wide variety of antimicrobial substances have been discovered, designed and synthesized; literally hundreds of drugs have been successfully used in some fashion over the years. Today ...

Microbiological quality of water from the rivers of Curitiba, Paraná State, Brazil, and the susceptibility to antimicrobial drugs and pathogenicity of Escherichia coli.

Science.gov (United States)

Giowanella, Melissa; Bozza, Angela; do Rocio Dalzoto, Patricia; Dionísio, Jair Alves; Andraus, Sumaia; Guimarães, Edson Luiz Gomes; Pimentel, Ida Chapaval

2015-11-01

Water safety is determined by several markers, and Escherichia coli is one of the most important indicators of water quality. The objective of this study was to evaluate the microbiological parameters in environmental samples of fresh water from rivers of Curitiba and its metropolitan area in Paraná State, Brazil. In addition, we evaluated the pathogenicity and susceptibility to antimicrobial drugs in E. coli. These evaluations were performed by quantitative and qualitative methods employing selective media for isolating thermotolerant coliforms and biochemical tests for identifying E. coli. Pathogenic strains of E. coli were detected by PCR multiplex using specific primers. From the water samples, 494 thermotolerant coliforms were obtained, of which 96 (19.43%) isolates were characterized as E. coli. Three isolates were identified as enteroaggregative E. coli, one as enterotoxigenic E. coli, one as enteropathogenic E. coli, and two carried the Eae virulence gene. E. coli susceptibility to commonly employed antimicrobial drugs was analyzed by the disc diffusion method. The results showed 49 (51.04%) isolates resistant to all the drugs assayed, 16 (16.67%) with an intermediate resistance to all drugs, and 31 (32.29%) intermediately or fully resistant to one or more drugs tested. The highest rate of resistance was observed for tetracycline 30 μg, streptomycin 10 μg, and ceftazidime 30 μg. Detection of E. coli is associated with water contamination by fecal material from humans and warm-blooded animals. The occurrence of resistant strains can be the result of the indiscriminate use of antimicrobial drugs and poor sanitation in the areas assayed.

75 FR 52751 - Office of Global Health Affairs; Trans-Atlantic Task Force on Antimicrobial Resistance (TATFAR)

Science.gov (United States)

2010-08-27

... appropriate therapeutic use of antimicrobial drugs in the medical and veterinary communities, prevention of... pipeline of new antimicrobial drugs, which could be better addressed by intensified cooperation.'' (2009 EU... Declaration: Appropriate therapeutic use of antimicrobial drugs in the medical and veterinary communities...

Models of antimicrobial pressure on intestinal bacteria of the treated host populations.

Science.gov (United States)

Volkova, V V; Cazer, C L; Gröhn, Y T

2017-07-01

Antimicrobial drugs are used to treat pathogenic bacterial infections in animals and humans. The by-stander enteric bacteria of the treated host's intestine can become exposed to the drug or its metabolites reaching the intestine in antimicrobially active form. We consider which processes and variables need to be accounted for to project the antimicrobial concentrations in the host's intestine. Those include: the drug's fraction (inclusive of any active metabolites) excreted in bile; the drug's fractions and intestinal segments of excretion via other mechanisms; the rates and intestinal segments of the drug's absorption and re-absorption; the rates and intestinal segments of the drug's abiotic and biotic degradation in the intestine; the digesta passage time through the intestinal segments; the rates, mechanisms, and reversibility of the drug's sorption to the digesta and enteric microbiome; and the volume of luminal contents in the intestinal segments. For certain antimicrobials, the antimicrobial activity can further depend on the aeration and chemical conditions in the intestine. Model forms that incorporate the inter-individual variation in those relevant variables can support projections of the intestinal antimicrobial concentrations in populations of treated host, such as food animals. To illustrate the proposed modeling framework, we develop two examples of treatments of bovine respiratory disease in beef steers by oral chlortetracycline and injectable third-generation cephalosporin ceftiofur. The host's diet influences the digesta passage time, volume, and digesta and microbiome composition, and may influence the antimicrobial loss due to degradation and sorption in the intestine. We consider two diet compositions in the illustrative simulations. The examples highlight the extent of current ignorance and need for empirical data on the variables influencing the selective pressures imposed by antimicrobial treatments on the host's intestinal bacteria.

Associations between Antimicrobial Resistance Phenotypes, Antimicrobial Resistance Genes, and Virulence Genes of Fecal Escherichia coli Isolates from Healthy Grow-Finish Pigs ▿

OpenAIRE

Rosengren, Leigh B.; Waldner, Cheryl L.; Reid-Smith, Richard J.

2009-01-01

Escherichia coli often carries linked antimicrobial resistance genes on transmissible genetic elements. Through coselection, antimicrobial use may select for unrelated but linked resistance or virulence genes. This study used unconditional statistical associations to investigate the relationships between antimicrobial resistance phenotypes and antimicrobial resistance genes in 151 E. coli isolates from healthy pigs. Phenotypic resistance to each drug was significantly associated with phenotyp...

The antimicrobial resistance containment and surveillance approach--a public health tool.

Science.gov (United States)

Simonsen, Gunnar S.; Tapsall, John W.; Allegranzi, Benedetta; Talbot, Elizabeth A.; Lazzari, Stefano

2004-01-01

Antimicrobial drug resistance (AMR) is widely recognized as a global public health threat because it endangers the effectiveness of treatment of infectious diseases. In 2001 WHO issued the Global Strategy for Containment of Antimicrobial Resistance, but it has proved difficult to translate the recommendations of the Global Strategy into effective public health actions. The purpose of the Antimicrobial Resistance Containment and Surveillance (ARCS) approach is to facilitate the formulation of public health programmes and the mobilization of human and financial resources for the containment of AMR. The ARCS approach highlights the fundamental link between rational drug use and containment of AMR. Clinical management of human and animal infections should be improved through better disease control and prevention, high quality diagnostic testing, appropriate treatment regimens and consumer health education. At the same time, systems for supplying antimicrobial drugs should include appropriate regulations, lists of essential drugs, and functional mechanisms for the approval and delivery of drugs. Containment of AMR is defined in the ARCS approach as the continuous application of this package of core interventions. Surveillance of the extent and trends of antimicrobial resistance as well as the supply, selection and use of antimicrobial drugs should be established to monitor the process and outcome of containment of AMR. The ARCS approach is represented in the ARCS diagram (Fig. 2) which provides a simplified, but comprehensive illustration of the complex problem of containment and monitoring of AMR. PMID:15654407

Antimicrobial synergy between carprofen and doxycycline against methicillin-resistant Staphylococcus pseudintermedius ST71.

Science.gov (United States)

Brochmann, Rikke Prejh; Helmfrid, Alexandra; Jana, Bimal; Magnowska, Zofia; Guardabassi, Luca

2016-06-24

New therapeutic strategies are needed to face the rapid spread of multidrug-resistant staphylococci in veterinary medicine. The objective of this study was to identify synergies between antimicrobial and non-antimicrobial drugs commonly used in companion animals as a possible strategy to restore antimicrobial susceptibility in methicillin-resistant Staphylococcus pseudintermedius (MRSP). A total of 216 antimicrobial/non-antimicrobial drug combinations were screened by disk diffusion using a clinical MRSP sequence type (ST) 71 strain resistant to all six antimicrobials tested (ampicillin, ciprofloxacin, clindamycin, doxycycline, oxacillin and trimethoprim/sulfamethoxazole). The most promising drug combination (doxycycline-carprofen) was further assessed by checkerboard testing extended to four additional MRSP strains belonging to ST71 or ST68, and by growth inhibition experiments. Seven non-antimicrobial drugs (bromhexine, acepromazine, amitriptyline, clomipramine, carprofen, fluoxetine and ketoconazole) displayed minimum inhibitory concentrations (MICs) ranging between 32 and >4096 mg/L, and enhanced antimicrobial activity of one or more antimicrobials. Secondary screening by checkerboard assay revealed a synergistic antimicrobial effect between carprofen and doxycycline, with the sum of the fractional inhibitory concentration indexes (ΣFICI) ranging between 0.3 and 0.5 depending on drug concentration. Checkerboard testing of multiple MRSP strains revealed a clear association between synergy and carriage of tetK, which is a typical feature of MRSP ST71. An increased growth inhibition was observed when MRSP ST71 cells in exponential phase were exposed to 0.5/32 mg/L of doxycycline/carprofen compared to individual drug exposure. Carprofen restores in vitro susceptibility to doxycycline in S. pseudintermedius strains carrying tetK such as MRSP ST71. Further research is warranted to elucidate the molecular mechanism behind the identified synergy and its linkage to

Drug use and antimicrobial resistance among Escherichia coli and Enterococcus spp. isolates from chicken and turkey flocks slaughtered in Quebec, Canada.

Science.gov (United States)

Boulianne, Martine; Arsenault, Julie; Daignault, Danielle; Archambault, Marie; Letellier, Ann; Dutil, Lucie

2016-01-01

An observational study was conducted of chicken and turkey flocks slaughtered at federal processing plants in the province of Quebec, Canada. The objectives were to estimate prevalence of drug use at hatchery and on farm and to identify antimicrobial resistance (AMR) in cecal Escherichia coli and Enterococcus spp. isolates and factors associated with AMR. Eighty-two chicken flocks and 59 turkey flocks were sampled. At the hatchery, the most used antimicrobial was ceftiofur in chickens (76% of flocks) and spectinomycin in turkeys (42% of flocks). Virginiamycin was the antimicrobial most frequently added to the feed in both chicken and turkey flocks. At least 1 E. coli isolate resistant to third-generation cephalosporins was present in all chicken flocks and in a third of turkey flocks. Resistance to tetracycline, streptomycin, and sulfisoxazole was detected in > 90% of flocks for E. coli isolates. Antimicrobial resistance (AMR) was observed to bacitracin, erythromycin, lincomycin, quinupristin-dalfopristin, and tetracycline in both chicken and turkey flocks for Enterococcus spp. isolates. No resistance to vancomycin was observed. The use of ceftiofur at hatchery was significantly associated with the proportion of ceftiofur-resistant E. coli isolates in chicken flocks. In turkey flocks, ceftiofur resistance was more frequent when turkeys were placed on litter previously used by chickens. Associations between drug use and resistance were observed with tetracycline (turkey) in E. coli isolates and with bacitracin (chicken and turkey), gentamicin (turkey), and tylosin (chicken) in Enterococcus spp. isolates. Further studies are needed to provide producers and veterinarians with alternative management practices and tools in order to reduce the use of antimicrobial feed additives in poultry.

Control of Antimicrobial Resistance Requires an Ethical Approach

Directory of Open Access Journals (Sweden)

Ben Parsonage

2017-11-01

Full Text Available Ethical behavior encompasses actions that benefit both self and society. This means that tackling antimicrobial resistance (AMR becomes an ethical obligation, because the prospect of declining anti-infectives affects everyone. Without preventive action, loss of drugs that have saved lives over the past century, will condemn ourselves, people we know, and people we don’t know, to unacceptable risk of untreatable infection. Policies aimed at extending antimicrobial life should be considered within an ethical framework, in order to balance the choice, range, and quality of drugs against stewardship activities. Conserving availability and effectiveness for future use should not compromise today’s patients. Practices such as antimicrobial prophylaxis for healthy people ‘at risk’ should receive full debate. There are additional ethical considerations for AMR involving veterinary care, agriculture, and relevant bio-industries. Restrictions for farmers potentially threaten the quality and quantity of food production with economic consequences. Antibiotics for companion animals do not necessarily spare those used for humans. While low-income countries cannot afford much-needed drugs, pharmaceutical companies are reluctant to develop novel agents for short-term return only. Public demand encourages over-the-counter, internet, black market, and counterfeit drugs, all of which compromise international control. Prescribers themselves require educational support to balance therapeutic choice against collateral damage to both body and environment. Predicted mortality due to AMR provides justification for international co-operation, commitment and investment to support surveillance and stewardship along with development of novel antimicrobial drugs. Ethical arguments for, and against, control of antimicrobial resistance strategies are presented and discussed in this review.

Strategies and molecular tools to fight antimicrobial resistance: resistome, transcriptome and antimicrobial peptides

Directory of Open Access Journals (Sweden)

Leticia Stephan Tavares

2013-12-01

Full Text Available The increasing number of antibiotic resistant bacteria motivates prospective research towards discovery of new antimicrobial active substances. There are, however, controversies concerning the cost-effectiveness of such research with regards to the description of new substances with novel cellular interactions, or description of new uses of existing substances to overcome resistance. Although examination of bacteria isolated from remote locations with limited exposure to humans has revealed an absence of antibiotic resistance genes, it is accepted that antibiotic resistance genes were both abundant and diverse in ancient living organisms, as detected in DNA recovered from Pleistocene deposits (30,000 years ago. Indeed, even before the first clinical use of antibiotics more than 60 years ago, resistant organisms had been isolated. Bacteria can exhibit different strategies for resistance against antibiotics. New genetic information may lead to the modification of protein structure affecting the antibiotic carriage into the cell, enzymatic inactivation of drugs, or even modification of cellular structure interfering in the drug-bacteria interaction. There are still plenty of new genes out there in the environment that can be appropriated by putative pathogenic bacteria to resist antimicrobial agents. On the other hand, there are compounds with antibiotic activity just waiting to be discovered. Antimicrobial peptides (AMPs are molecules which are wide-spread in all forms of life, from multi-cellular organisms to bacterial cells used to interfere with microbial growth. Several AMPs have been shown to be effective against multi-drug resistant bacteria and have low propensity to resistance development, probably due to their unique mode of action, different from well known antimicrobial drugs. These substances may interact in different ways with bacterial cell membrane, protein synthesis, protein modulation and protein folding.

Distribution, detection of enterotoxigenic strains and antimicrobial drug susceptibility patterns of Bacteroides fragilis group in diarrheic and non-diarrheic feces from Brazilian infants

Directory of Open Access Journals (Sweden)

Débora Paula Ferreira

2010-10-01

Full Text Available Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrheic (n=110 and non-diarrheic (n=65 fecal samples from children aged 0-5 years old were evaluated. BFG strains were isolated and identified by conventional biochemical, physiological and molecular approaches. Alternatively, bacteria and enterotoxigenic strains were detected directly from feces by molecular biology. Antimicrobial drug susceptibility patterns were determined by the agar dilution method according to the guidelines for isolated bacteria. BFG was detected in 64.3% of the fecal samples (55% diarrheic and 80.4% non-diarrheic, and 4.6% were enterotoxigenic. Antimicrobial resistance was observed against ampicillin, ampicillin/sulbactam, piperacillin/tazobactam, meropenem, ceftriaxone, clindamycin and chloramphenicol. The data show that these bacteria are prevalent in fecal microbiota at higher levels in healthy children. The molecular methodology was more effective in identifying the B. fragilis group when compared to the biochemical and physiological techniques. The observation of high resistance levels stimulates thoughts about the indiscriminate use of antimicrobial drugs in early infancy. Further quantitative studies are needed to gain a better understanding of the role of these bacteria in acute diarrhea in children.

Studies of the impact of occupational exposure of pharmaceutical workers on the development of antimicrobial drug resistance.

Science.gov (United States)

Sarker, Md Moklesur Rahman; Islam, Kamrun Nahar; Huri, Hasniza Zaman; Rahman, Monzur; Imam, Hasan; Hosen, Md Biplob; Mohammad, Nur; Sarker, Md Zaidul Islam

2014-01-01

Pharmaceutical workers involved with the production of antimicrobial drugs are exposed to various antimicrobial chemicals in different steps of manufacturing such as grinding, sieving, compression, granulation, mixing and filling. These exposures may lead to the development of multidrug resistance (MDR) in bacteria. Scientific reports on the occupational health hazard of pharmaceutical workers involved in manufacturing antibiotics are scarce. The present study aimed to compare the degree of bacterial resistance in pharmaceutical workers in Bangladesh to that of individuals not involved in the pharmaceutical field. Twenty male workers from five local pharmaceutical companies and twenty male subjects not involved in the pharmaceutical field (non-pharmaceutical subjects) were randomly selected. Nasal fluid, mucus/cough and stool specimens were collected from each subject and were cultured separately at 37°C for 24 hours to obtain bacterial growth. The cultured species were then identified, isolated and subjected to microbial sensitivity testing against 18 different antibiotics from eight different groups by the disk diffusion method. Staphylococcus spp., Pseudomonas spp. and Escherichia coli were identified and isolated from the culture of nasal fluids, mucuses and stools, respectively. All the isolated species of bacteria exhibited significant enhancement of the degree of MDR in pharmaceutical workers compared with non-pharmaceutical subjects. Workers with a longer working history had greater degree of antibiotic resistance and vice versa. It can be certainly considered that the exposure of pharmaceutical workers to antibiotic agents resulted in a high incidence of multidrug resistance. Effective steps should be taken to minimize inherent exposure of pharmaceutical workers to antibiotics during work to prevent antimicrobial drug resistance.

Potential of berberine to enhance antimicrobial activity of commonly used antibiotics for dairy cow mastitis caused by multiple drug-resistant Staphylococcus epidermidis infection.

Science.gov (United States)

Zhou, X; Yang, C; Li, Y; Liu, X; Wang, Y

2015-08-19

Berberine is a plant alkaloid with antimicrobial activity against a variety of microorganisms. In this study, the antimicrobial properties of berberine against multi-drug resistant field isolates of Staphylococcus epidermidis were investigated using berberine alone or in combination with a commonly used antibiotics in veterinary clinics, including penicillin, lincomycin, and amoxicillin. The results indicated that the minimum inhibitory concentrations of berberine, penicillin, lincomycin, and amoxicillin against field S. epidermidis isolates were 2-512, 0.8-213, 0.4-1024, and 0.4-256 mg/mL, respectively. Furthermore, the synergistic effects of antimicrobial activity against these multi-drug resistant isolates were observed when the berberine was combined with penicillin, lincomycin, or amoxicillin; no antagonistic effect of the combination was detected in any of the clinical isolates. These observations were further confirmed using a time-killing assay, in which a combination of 2 agents yielded a greater than 2.03-2.44 log10 decrease in colony-forming unit/mL compared with each agent alone. These findings suggest that berberine is a promising compound for preventing and treating multi-drug resistant S. epidermidis infected mastitis in dairy cows either alone or in combination with other commonly used antibiotics, such as penicillin, lincomycin, and amoxicillin.

Antimicrobial drug resistance at the human-animal interface in Vietnam

NARCIS (Netherlands)

Nguyen, V.T.

2017-01-01

This thesis investigates the prevalence of antimicrobial resistance (AMR) among non-typhoidal Salmonella (NTS) and E. coli strains isolated from backyard farm chickens and humans in Vietnam. We found that this prevalence was to some extent related to antimicrobial usage. In particular,

Antimicrobial polymers.

Science.gov (United States)

Jain, Anjali; Duvvuri, L Sailaja; Farah, Shady; Beyth, Nurit; Domb, Abraham J; Khan, Wahid

2014-12-01

Better health is basic requirement of human being, but the rapid growth of harmful pathogens and their serious health effects pose a significant challenge to modern science. Infections by pathogenic microorganisms are of great concern in many fields such as medical devices, drugs, hospital surfaces/furniture, dental restoration, surgery equipment, health care products, and hygienic applications (e.g., water purification systems, textiles, food packaging and storage, major or domestic appliances etc.) Antimicrobial polymers are the materials having the capability to kill/inhibit the growth of microbes on their surface or surrounding environment. Recently, they gained considerable interest for both academic research and industry and were found to be better than their small molecular counterparts in terms of enhanced efficacy, reduced toxicity, minimized environmental problems, resistance, and prolonged lifetime. Hence, efforts have focused on the development of antimicrobial polymers with all desired characters for optimum activity. In this Review, an overview of different antimicrobial polymers, their mechanism of action, factors affecting antimicrobial activity, and application in various fields are given. Recent advances and the current clinical status of these polymers are also discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Advances in Development of Antimicrobial Peptidomimetics as Potential Drugs.

Science.gov (United States)

Molchanova, Natalia; Hansen, Paul R; Franzyk, Henrik

2017-08-29

The rapid emergence of multidrug-resistant pathogens has evolved into a global health problem as current treatment options are failing for infections caused by pan-resistant bacteria. Hence, novel antibiotics are in high demand, and for this reason antimicrobial peptides (AMPs) have attracted considerable interest, since they often show broad-spectrum activity, fast killing and high cell selectivity. However, the therapeutic potential of natural AMPs is limited by their short plasma half-life. Antimicrobial peptidomimetics mimic the structure and biological activity of AMPs, but display extended stability in the presence of biological matrices. In the present review, focus is on the developments reported in the last decade with respect to their design, synthesis, antimicrobial activity, cytotoxic side effects as well as their potential applications as anti-infective agents. Specifically, only peptidomimetics with a modular structure of residues connected via amide linkages will be discussed. These comprise the classes of α-peptoids ( N -alkylated glycine oligomers), β-peptoids ( N -alkylated β-alanine oligomers), β³-peptides, α/β³-peptides, α-peptide/β-peptoid hybrids, α/γ N -acylated N -aminoethylpeptides (AApeptides), and oligoacyllysines (OAKs). Such peptidomimetics are of particular interest due to their potent antimicrobial activity, versatile design, and convenient optimization via assembly by standard solid-phase procedures.

Prevention strategies for antimicrobial resistance: a systematic review of the literature

Directory of Open Access Journals (Sweden)

Whitney P Caron

2010-05-01

Full Text Available Whitney P Caron1, Shaker A Mousa1,21The Pharmaceutical Research Institute, Center of Excellence of Infection Prevention (CEIP, Albany College of Pharmacy and Health Sciences, Albany, NY, USA; 2King Saud University, Riyadh, Saudi ArabiaAbstract: Antibiotics offer great benefits by reducing the duration and severity of illnesses and aiding in infection transmission control. With this being said, the inexorable process of antimicrobial drug resistance is to some degree unavoidable. Although drug resistance will likely persist and is to be expected, the overall level can be dramatically decreased with increased attention to antibiotic overuse and the pharmacokinetic and pharmacodynamic properties of different drug formulations, and the use of proper hygiene and protective barriers. Implementation of such practices as microbial surveillance and prophylaxis has been shown to result in decreased hospital length of stay, health care costs and mortality due to drug-resistant infections. This review will summarize current progress in preventative techniques aimed at reducing the incidence of infection by antimicrobial-resistant bacteria and the emergence and spread of antimicrobial-resistant strains. By employing a variety of prevention strategies, including proper personal hygiene, prescreening for carrier status before hospital admission, disinfection of hospital rooms, and careful monitoring of antimicrobial prescribing, marked progress can be achieved in the control of drug-resistant pathogens, which can translate into more effective antimicrobial therapy.Keywords: infection prevention, antibiotic, personal hygiene, disinfection, microbial surveillance, drug-resistant pathogen

Repurposing salicylanilide anthelmintic drugs to combat drug resistant Staphylococcus aureus.

Science.gov (United States)

Rajamuthiah, Rajmohan; Fuchs, Beth Burgwyn; Conery, Annie L; Kim, Wooseong; Jayamani, Elamparithi; Kwon, Bumsup; Ausubel, Frederick M; Mylonakis, Eleftherios

2015-01-01

Staphylococcus aureus is a Gram-positive bacterium that has become the leading cause of hospital acquired infections in the US. Repurposing Food and Drug Administration (FDA) approved drugs for antimicrobial therapy involves lower risks and costs compared to de novo development of novel antimicrobial agents. In this study, we examined the antimicrobial properties of two commercially available anthelmintic drugs. The FDA approved drug niclosamide and the veterinary drug oxyclozanide displayed strong in vivo and in vitro activity against methicillin resistant S. aureus (minimum inhibitory concentration (MIC): 0.125 and 0.5 μg/ml respectively; minimum effective concentration: ≤ 0.78 μg/ml for both drugs). The two drugs were also effective against another Gram-positive bacteria Enterococcus faecium (MIC 0.25 and 2 μg/ml respectively), but not against the Gram-negative species Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter aerogenes. The in vitro antimicrobial activity of niclosamide and oxyclozanide were determined against methicillin, vancomycin, linezolid or daptomycin resistant S. aureus clinical isolates, with MICs at 0.0625-0.5 and 0.125-2 μg/ml for niclosamide and oxyclozanide respectively. A time-kill study demonstrated that niclosamide is bacteriostatic, whereas oxyclozanide is bactericidal. Interestingly, oxyclozanide permeabilized the bacterial membrane but neither of the anthelmintic drugs exhibited demonstrable toxicity to sheep erythrocytes. Oxyclozanide was non-toxic to HepG2 human liver carcinoma cells within the range of its in vitro MICs but niclosamide displayed toxicity even at low concentrations. These data show that the salicylanilide anthelmintic drugs niclosamide and oxyclozanide are suitable candidates for mechanism of action studies and further clinical evaluation for treatment of staphylococcal infections.

Campylobacter Antimicrobial Drug Resistance among Humans in ...

African Journals Online (AJOL)

Background: Though Campylobacter enteritis is a self-limiting disease, antimicrobial agents are recommended for extraintestinal infections and for treating immunocompromised persons. ... The in-vitro antibiotic susceptibility testing for all organisms was performed by employing the Kirby- Bauer disc diffusion method.

Pediatric Obesity: Pharmacokinetic Alterations and Effects on Antimicrobial Dosing.

Science.gov (United States)

Natale, Stephanie; Bradley, John; Nguyen, William Huy; Tran, Tri; Ny, Pamela; La, Kirsten; Vivian, Eva; Le, Jennifer

2017-03-01

Limited data exist for appropriate drug dosing in obese children. This comprehensive review summarizes pharmacokinetic (PK) alterations that occur with age and obesity, and these effects on antimicrobial dosing. A thorough comparison of different measures of body weight and specific antimicrobial agents including cefazolin, cefepime, ceftazidime, daptomycin, doripenem, gentamicin, linezolid, meropenem, piperacillin-tazobactam, tobramycin, vancomycin, and voriconazole is presented. PubMed (1966-July 2015) and Cochrane Library searches were performed using these key terms: children, pharmacokinetic, obesity, overweight, body mass index, ideal body weight, lean body weight, body composition, and specific antimicrobial drugs. PK studies in obese children and, if necessary, data from adult studies were summarized. Knowledge of PK alterations stemming from physiologic changes that occur with age from the neonate to adolescent, as well as those that result from increased body fat, become an essential first step toward optimizing drug dosing in obese children. Excessive amounts of adipose tissue contribute significantly to body size, total body water content, and organ size and function that may modify drug distribution and clearance. PK studies that evaluated antimicrobial dosing primarily used total (or actual) body weight (TBW) for loading doses and TBW or adjusted body weight for maintenance doses, depending on the drugs' properties and dosing units. PK studies in obese children are imperative to elucidate drug distribution, clearance, and, consequently, the dose required for effective therapy in these children. Future studies should evaluate the effects of both age and obesity on drug dosing because the incidence of obesity is increasing in pediatric patients. © 2017 Pharmacotherapy Publications, Inc.

Bacteriuria and antimicrobial susceptibility pattern of bacterial ...

African Journals Online (AJOL)

Bacterial isolates and drug susceptibility patterns of urinary tract infection among ... Key words: Urinary tract infection, pregnant women, antimicrobial drug ..... and premature labour as well as adverse outcome for the unborn child (Raz, 2003).

Antimicrobial and anticancer activities of extracts from Urginea ...

African Journals Online (AJOL)

Background: Increasing antibiotic resistance among human pathogenic microorganisms and the failure of conventional cancer therapies attracting great attention among scientists in the field of herbal medicine to develop natural antimicrobial and anticancer drugs. Thus, the antimicrobial and anticancer activities from fruits ...

Antimicrobial Use: A Risk Factor or a Protective Factor for Acquiring Campylobacteriosis?

DEFF Research Database (Denmark)

Koningstein, Maike; Simonsen, Jacob; Helms, Morten

2011-01-01

Background. It is well acknowledged that the use of antimicrobial drugs in food animals leads to antimicrobial drug resistance in foodborne bacteria such as Campylobacter; however, the role of human antimicrobial usage is much less investigated. The aim of this study was to quantify the odds...... with increased risk (OR, 2.5; 95% CI, 1.8–3.5). This risk was higher for resistant isolates than for susceptible ones. CONCLUSIONS: Treatment with macrolides may protect against Campylobacter infection for a limited period of time, possibly due to the antibacterial effects of the drug or its metabolites...

In Vitro Antimicrobial Potential of the Lichen Parmotrema sp. Extracts against Various Pathogens

OpenAIRE

Chauhan, Ritika; Abraham, Jayanthi

2013-01-01

  Objective(s):   The ongoing increasing antibiotic resistance is one of the biggest challenges faced by global public health. The perennial need for new antimicrobials against a background of increasing antibiotic resistance in pathogenic and opportunistic microorganisms obliges the scientific community to constantly develop new drugs and antimicrobial agents. Lichens are known prolific sources of natural antimicrobial drugs and biologically active natural products. This study ...

Repurposing Auranofin, Ebselen, and PX-12 as Antimicrobial Agents Targeting the Thioredoxin System

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Holly C. May

2018-03-01

Full Text Available As microbial resistance to drugs continues to rise at an alarming rate, finding new ways to combat pathogens is an issue of utmost importance. Development of novel and specific antimicrobial drugs is a time-consuming and expensive process. However, the re-purposing of previously tested and/or approved drugs could be a feasible way to circumvent this long and costly process. In this review, we evaluate the U.S. Food and Drug Administration tested drugs auranofin, ebselen, and PX-12 as antimicrobial agents targeting the thioredoxin system. These drugs have been shown to act on bacterial, fungal, protozoan, and helminth pathogens without significant toxicity to the host. We propose that the thioredoxin system could serve as a useful therapeutic target with broad spectrum antimicrobial activity.

Antimicrobial resistance in aerobic bacteria isolated from oral ...

African Journals Online (AJOL)

... varied antimicrobial susceptibility patterns. The oral cavities of hunting dogs are laden with multi-drug resistant bacteria of significant public health importance that could be transferred to humans through contaminated hunted games and bite wound. Keywords: Aerobic bacteria, Antimicrobial resistance, Dogs, Oral cavity, ...

Antimicrobial potentials of silver colloidal (nanorods) on clinical ...

African Journals Online (AJOL)

Antimicrobial resistance in developing countries has long been an issue of major concern. Nanotechnology has become an eye opener for the intervention on multiple drug resistance organisms. In this study we investigated the antimicrobial potentials of Silver Nitrate (nanorods) solution used in managing infectious ...

Antimicrobial potentials of Helicteres isora silver nanoparticles against extensively drug-resistant (XDR) clinical isolates of Pseudomonas aeruginosa.

Science.gov (United States)

Mapara, Nikunj; Sharma, Mansi; Shriram, Varsha; Bharadwaj, Renu; Mohite, K C; Kumar, Vinay

2015-12-01

Pseudomonas aeruginosa is a leading opportunistic pathogen and its expanding drug resistance is a growing menace to public health. Its ubiquitous nature and multiple resistance mechanisms make it a difficult target for antimicrobial chemotherapy and require a fresh approach for developing new antimicrobial agents against it. The broad-spectrum antibacterial effects of silver nanoparticles (SNPs) make them an excellent candidate for use in the medical field. However, attempts made to check their potency against extensively drug-resistant (XDR) microbes are meager. This study describes the biosynthesis and biostabilization of SNPs by Helicteres isora aqueous fruit extract and their characterization by ultraviolet-visible spectroscopy, transmission electron microscopy, dynamic light scattering, X-ray diffraction, and Fourier transform infrared spectroscopy. Majority of SNPs synthesized were of 8--20-nm size. SNPs exhibited dose-dependent antibacterial activities against four XDR P. aeruginosa (XDR-PA) clinical isolates as revealed by growth curves, with a minimum inhibitory concentration of 300 μg/ml. The SNPs exhibited antimicrobial activity against all strains, with maximum zone of inhibition (16.4 mm) in XRD-PA-2 at 1000 μg/ml. Amongst four strains, their susceptibilities to SNPs were in the following order: XDR-PA-2 > XDR-PA-4 > XDR-PA-3 > XDR-PA-1. The exposure of bacterial cells to 300 μg/ml SNPs resulted into a substantial leakage of reducing sugars and proteins, inactivation of respiratory chain dehydrogenases, and eventual cell death. SNPs also induced lipid peroxidation, a possible underlying factor to membrane porosity. The effects were more pronounced in XDR-PA-2 which may be correlated with its higher susceptibility to SNPs. These results are indicative of SNP-induced turbulence of membranous permeability as an important causal factor in XDR-PA growth inhibition and death.

Animation of Antimicrobial Resistance

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Full Text Available ... bacteria. Over time, the use of antimicrobial drugs will result in the development of resistant strains of ... and other key audiences. We hope this animation will make the concept more understandable to non-scientists ...

Animation of Antimicrobial Resistance

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Full Text Available ... it More sharing options Linkedin Pin it Email Print The Food and Drug Administration's (FDA's) Center for ... issue of antimicrobial resistance is that the subject material appears abstract and is complex. This video was ...

Animation of Antimicrobial Resistance

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Full Text Available ... use of antimicrobial drugs will result in the development of resistant strains of bacteria, complicating clinician's efforts ... Inspections & Compliance Federal, State & Local Officials Consumers Health Professionals Science & Research Industry Scroll back to top Popular ...

Animation of Antimicrobial Resistance

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Full Text Available ... One of the major obstacles to understanding the issue of antimicrobial resistance is that the subject material ... Website Policies U.S. Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 1-888- ...

Prophylactic and metaphylactic antimicrobial use in Belgian fattening pig herds.

Science.gov (United States)

Callens, Bénédicte; Persoons, Davy; Maes, Dominiek; Laanen, Maria; Postma, Merel; Boyen, Filip; Haesebrouck, Freddy; Butaye, Patrick; Catry, Boudewijn; Dewulf, Jeroen

2012-09-01

The monitoring of antimicrobial use is an essential step to control the selection and spread of antimicrobial resistance. Between January and October 2010 data on prophylactic and metaphylactic antimicrobial use were collected retrospectively on 50 closed or semi-closed pig herds. Ninety-three percent of the group treatments were prophylactic whereas only 7% were methaphylactic. The most frequently used antimicrobials orally applied at group level were colistin (30.7%), amoxicillin (30.0%), trimethoprim-sulfonamides (13.1%), doxycycline (9.9%) and tylosin (8.1%). The most frequently applied injectable antimicrobials were tulathromycin (45.0%), long acting ceftiofur (40.1%) and long acting amoxicillin (8.4%). The treatment incidences (TI) based on the used daily dose pig (UDD(pig) or the actually administered dose per day per kg pig of a drug) for all oral and injectable antimicrobial drugs was on average 200.7 per 1000 pigs at risk per day (min=0, max=699.0), while the TI based on the animal daily dose pig (ADD(pig) or the national defined average maintenance dose per day per kg pig of a drug used for its main indication) was slightly higher (average=235.8, min=0, max=1322.1). This indicates that in reality fewer pigs were treated with the same amount of antimicrobials than theoretically possible. Injectable products were generally overdosed (79.5%), whereas oral treatments were often underdosed (47.3%). In conclusion, this study shows that prophylactic group treatment was applied in 98% of the visited herds and often includes the use of critically important and broad-spectrum antimicrobials. In Belgium, the guidelines for prudent use of antimicrobials are not yet implemented. Copyright © 2012 Elsevier B.V. All rights reserved.

Mechanism of activity, biosynthesis and identification of beta-lactam antimicrobial drugs

Directory of Open Access Journals (Sweden)

Marija Sedak

2011-01-01

Full Text Available Antimicrobal drugs are chemotherapeutics with a wide spectrum of use in human and veterinary medicine and livestock practice. Beta-lactams are the most widespread group of antimicrobal drugs and are most often used in human and veterinary medicine in the treatment of bacterial infections due to their powerful antimicrobial activity and very low toxicity. They are divided into the groups of penicillins, cefalosporins and monobactams. Penicillins are obtained from the filtrate of the mould cultures Penicillium notatum and Penicillium chrysogenum, while cefalosporins are obtained from the filtrate of the actinomycete cultures (Cephalosporium acremonium. Research has lead to the discovery of active groups of 6-amino-penicillin acids, whose isolation has made it possible to produce semi-synthetic penicillins that have surpassed the limitations of natural penicillin G. The physico-chemical properties of the beta-lactams can be altered by substituting hydrogen in the carboxyl group of penicillins, i.e. in modifying the side chain of cefalosporin. This increases the resistance to the activity of β-lactamase and expands the spectrum of activity. Beta-lactams, in therapy concentrations, act as a bacteriocide by inhibiting the synthesis of bacterial cell walls. Penicillins are important for antibacterial chemotherapy, often in combination with other antimicrobal drugs. Cefalosporins are usually used as a replacement for penicillin in treating infections caused by gram-negative bacteria and in prophylaxis for surgery. The use of beta-lactams in animals used for food can result in the residues of these drugs in meat and meat products or milk and eggs. The introduction of antimicrobal drugs in the human body via food is particularly dangerous due to their direct toxicity or carcinogenicity, influences on the composition of the intestinal microflora, possible allergic reactions in sensitive people, and the appearance of resistance of individual pathogenic

Animation of Antimicrobial Resistance

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Full Text Available ... Español Search FDA Submit search Popular Content Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, ... Biologics Animal & Veterinary Cosmetics Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of ...

Antimicrobial resistance in aerobic bacteria isolated from oral ...

African Journals Online (AJOL)

This study reinforces the need for dog bite wound microbial culture and antimicrobial sensitivity test as isolates showed varied antimicrobial susceptibility patterns. The oral cavities of hunting dogs are laden with multi-drug resistant bacteria of significant public health importance that could be transferred to humans through ...

Antimicrobial Activity of Methanolic Extracts of Sambucus ebulus ...

African Journals Online (AJOL)

Background: Increase in the emergence of drug - resistant pathogens led to the development of natural antimicrobials. In this study the antimicrobial effect of methanolic extracts of Sambucus ebulus and Urtica dioica on 16 skin and wound infections isolates of methicillin resistant. S. aureus have been studied. Material and ...

Health risk from veterinary antimicrobial use in China's food animal production and its reduction.

Science.gov (United States)

Hu, Yuanan; Cheng, Hefa

2016-12-01

The overuse and misuse of veterinary drugs, particularly antimicrobials, in food animal production in China cause environmental pollution and wide food safety concerns, and pose public health risk with the selection of antimicrobial resistance (AMR) that can spread from animal populations to humans. Elevated abundance and diversity of antimicrobial resistance genes (ARGs) and resistant bacteria (including multi-drug resistant strains) in food-producing animals, food products of animal origin, microbiota of human gut, and environmental media impacted by intensive animal farming have been reported. To rein in drug use in food animal production and protect public health, the government made a total of 227 veterinary drugs, including 150 antimicrobial products, available only by prescription from licensed veterinarians for curing, controlling, and preventing animal diseases in March 2014. So far the regulatory ban on non-therapeutic use has failed to bring major changes to the long-standing practice of drug overuse and misuse in animal husbandry and aquaculture, and significant improvement in its implementation and enforcement is necessary. A range of measures, including improving access to veterinary services, strengthening supervision on veterinary drug production and distribution, increasing research and development efforts, and enhancing animal health management, are recommended to facilitate transition toward rational use of veterinary drugs, particularly antimicrobials, and to reduce the public health risk arising from AMR development in animal agriculture. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pharmacoepidemiological observational study of antimicrobial use in outpatients of ophthalmology department in North Indian population

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Hina Kauser

2018-01-01

Full Text Available Background: Recognition of drug usage patterns provides the basis for improving safety and plummeting risks associated with their use. Thus, this study was undertaken to explore the drug usage pattern in ophthalmology with an emphasis on antimicrobial use at a tertiary care teaching hospital. Materials and Methods: An observational study was conducted in the Department of Ophthalmology, Hakeem Abdul Hameed Centenary Hospital, Jamia Hamdard, New Delhi, India for 9 months. Newly registered patients visiting the Outpatient Department for curative complaints were included. All drugs prescribed were recorded, including dose, route, dosage form, frequency of administration, indications for prescription, and duration of therapy, and the data was audited using the indicators prescribed by the World Health Organization. Result: A total of 600 prescriptions were analyzed. The number of drugs prescribed was 1097 with an average drug per prescription being 1.8. The most common disorders diagnosed were infective conjunctivitis (21.5% followed by stye (5.5%. Drugs were prescribed in different dosage forms with eye drops (72.6% being the most common. Drugs were predominantly prescribed by brand name (100%. Antimicrobials (44.7% were the most commonly prescribed drugs followed by lubricants (17.5%. Moxifloxacin (53.5% was the most commonly prescribed antimicrobial agent. Of the antimicrobials prescribed, 89.6% were prescribed topically. Average total cost per prescription was 113 INR. Conclusion: The study concludes with an overall impression of rational prescription in terms of prescribing in consensus with the recommended treatment protocol of ocular diseases. Nevertheless, health-care professionals should be encouraged to prescribe by generic name. Creating awareness regarding selection of drugs from essential drug list to reduce the drug cost is the need of the hour. Last but not least, updating knowledge regarding appropriate antimicrobial use and the

Antimicrobial Peptides (AMPs

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Mehrzad Sadredinamin

2016-04-01

Full Text Available Antimicrobial peptides (AMPs are extensive group of molecules that produced by variety tissues of invertebrate, plants, and animal species which play an important role in their immunity response. AMPs have different classifications such as; biosynthetic machines, biological sources, biological functions, molecular properties, covalent bonding patterns, three dimensional structures, and molecular targets.These molecules have multidimensional properties including antimicrobial activity, antiviral activity, antifungal activity, anti-parasite activity, biofilm control, antitumor activity, mitogens activity and linking innate to adaptive immunity that making them promising agents for therapeutic drugs. In spite of this advantage of AMPs, their clinical developments have some limitation for commercial development. But some of AMPs are under clinical trials for the therapeutic purpose such as diabetic foot ulcers, different bacterial infections and tissue damage. In this review, we emphasized on the source, structure, multidimensional properties, limitation and therapeutic applications of various antimicrobial peptides.

Antimicrobial residues and resistance against critically important antimicrobials in non-typhoidal Salmonella from meat sold at wet markets and supermarkets in Vietnam.

OpenAIRE

Nhung, NT; Van, NTB; Cuong, NV; Duong, TTQ; Nhat, TT; Hang, TTT; Nhi, NTH; Kiet, BT; Hien, VB; Ngoc, PT; Campbell, J; Thwaites, G; Carrique-Mas, J

2017-01-01

Excessive antimicrobial usage and deficiencies in hygiene in meat production systems may result in undesirable human health hazards, such as the presence of antimicrobial drug residues and non-typhoidal Salmonella (NTS), including antimicrobial resistant (AMR) NTS. Recently, Vietnam has witnessed the emergence of integrated intensive animal production systems, coexisting with more traditional, locally-sourced wet markets. To date no systematic studies have been carried out to compare health h...

Antimicrobial synergy between carprofen and doxycycline against methicill-inresistant Staphylococcus pseudintermedius ST71

DEFF Research Database (Denmark)

Brochmann, Rikke Prejh; Helmfrid, Linn Alexandra; Jana, Bimal

2016-01-01

. Seven non-antimicrobial drugs (bromhexine, acepromazine, amitriptyline, clomipramine, carprofen, fluoxetine and ketoconazole) displayed minimum inhibitory concentrations (MICs) ranging between 32 and >4096 mg/L, and enhanced antimicrobial activity of one or more antimicrobials. Secondary screening...

Nanoparticles: Alternatives Against Drug-Resistant Pathogenic Microbes

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Gudepalya Renukaiah Rudramurthy

2016-06-01

Full Text Available Antimicrobial substances may be synthetic, semisynthetic, or of natural origin (i.e., from plants and animals. Antimicrobials are considered “miracle drugs” and can determine if an infected patient/animal recovers or dies. However, the misuse of antimicrobials has led to the development of multi-drug-resistant bacteria, which is one of the greatest challenges for healthcare practitioners and is a significant global threat. The major concern with the development of antimicrobial resistance is the spread of resistant organisms. The replacement of conventional antimicrobials by new technology to counteract antimicrobial resistance is ongoing. Nanotechnology-driven innovations provide hope for patients and practitioners in overcoming the problem of drug resistance. Nanomaterials have tremendous potential in both the medical and veterinary fields. Several nanostructures comprising metallic particles have been developed to counteract microbial pathogens. The effectiveness of nanoparticles (NPs depends on the interaction between the microorganism and the NPs. The development of effective nanomaterials requires in-depth knowledge of the physicochemical properties of NPs and the biological aspects of microorganisms. However, the risks associated with using NPs in healthcare need to be addressed. The present review highlights the antimicrobial effects of various nanomaterials and their potential advantages, drawbacks, or side effects. In addition, this comprehensive information may be useful in the discovery of broad-spectrum antimicrobial drugs for use against multi-drug-resistant microbial pathogens in the near future.

Antimicrobial resistance of thermophilic Campylobacter

DEFF Research Database (Denmark)

Aarestrup, Frank Møller; Engberg, J.

2001-01-01

Campylobacter has become the leading cause of zoonotic enteric infections in developed and developing countries world-wide. Antimicrobial resistance has emerged among Campylobacter mainly as a consequence of the use of antimicrobial agents in food animal production. Resistance to drugs of choice...... for the treatment of infections, macrolides and fluoroquinolones has emerged as a clinical problem and interventions to reduce this are recommended. Resistance to fluoroquinolones and macrolides is mediated by chromosomal mutations. Resistance to other relevant antimicrobial agents, mediated by acquired resistance...... genes, has not become widespread so far. However, resistance genes originating from both Gram-positive and Gram-negative bacterial species have been found, showing the potential for acquired resistance to emerge in Campylobacter....

Improved antimicrobial property and controlled drug release kinetics of silver sulfadiazine loaded ordered mesoporous silica

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Suman Jangra

2016-09-01

Full Text Available The present study deals with the loading of silver sulfadiazine into ordered mesoporous silica material by post-impregnation method and its effect on the in vitro release kinetics and antimicrobial property of the drug. The formulated SBA-15 silica material with rope-like morphology and SBA-15-silver sulfadiazine (SBA-AgSD were characterized by UV–visible spectrophotometer, small and wide-angle powder X-ray diffraction (PXRD, field emission scanning electron microscope (FESEM and high resolution transmission electron microscope (HRTEM. Thermo-gravimetric analysis of SBA-AgSD revealed a high loading amount of 52.87%. Nitrogen adsorption–desorption analysis confirmed the drug entrapment into host material by revealing a reduced surface area (214 m2/g and pore diameter (6.7 nm of the SBA-AgSD. The controlled release of silver sulfadiazine drug from the mesoporous silica to simulated gastric, intestinal and body fluids was evaluated. The Korsmeyer–Peppas model fits the drug release data with the non-Fickian diffusion model and zero order kinetics of SBA-AgSD. The antibacterial performance of the SBA-AgSD was evaluated with respect to Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa. The controlled drug delivery of the SBA-AgSD revealed improved antibacterial activity, thus endorsing its applicability in effective wound dressing.

Antimicrobial Compounds from Marine Invertebrates-Derived Microorganisms.

Science.gov (United States)

Liu, Juan; Jung, Jee H; Liu, Yonghong

2016-01-01

It is known that marine invertebrates, including sponges, tunicates, cnidaria or mollusks, host affluent and various communities of symbiotic microorganisms. The microorganisms associated with the invertebrates metabolized various biologically active compounds, which could be an important resource for the discovery and development of potentially novel drugs. In this review, the new compounds with antimicrobial activity isolated from marine invertebrate-derived microorganisms in the last decade (2004-2014) will be presented, with focus on the relevant antimicrobial activities, origin of isolation, and information of strain species. New compounds without antimicrobial activity were not revealed.

AMPA: an automated web server for prediction of protein antimicrobial regions.

Science.gov (United States)

Torrent, Marc; Di Tommaso, Paolo; Pulido, David; Nogués, M Victòria; Notredame, Cedric; Boix, Ester; Andreu, David

2012-01-01

AMPA is a web application for assessing the antimicrobial domains of proteins, with a focus on the design on new antimicrobial drugs. The application provides fast discovery of antimicrobial patterns in proteins that can be used to develop new peptide-based drugs against pathogens. Results are shown in a user-friendly graphical interface and can be downloaded as raw data for later examination. AMPA is freely available on the web at http://tcoffee.crg.cat/apps/ampa. The source code is also available in the web. marc.torrent@upf.edu; david.andreu@upf.edu Supplementary data are available at Bioinformatics online.

In vitro sensitivities to antimicrobial drugs of ureaplasmas isolated from the bovine respiratory tract, genital tract and eye.

Science.gov (United States)

Kishima, M; Hashimoto, K

1979-09-01

The sensitivity to 18 antimicrobial drugs was examined for 66 strains of Ureaplasma sp isolated from respiratory tracts of calves suffering from enzootic pneumonia, urinary tracts of bulls and eyes of cows suffering from infectious bovine kerato-conjunctivitis. Furamizole, tiamulin fumarate, erythromycin lactobionate, malidomycin C, doxycycline hydrochloride, kitasamycin tartrate, tylosin tartrate, T-2636C, tetracycline hydrochloride, oxytetracycline hydrochloride, chlortetracycline hydrochloride, oleandomycin phosphate, furazolidone, spiramycin adipate, chloramphenicol and thiophenicol showed strong inhibiting activity on all the test strains. Among them, furamizole, tiamulin fumarate and erythromycin lactobionate were most active. Kanamycin sulphate showed weak activity on all the strains tested. The differences in origin of the test strains did not affect their sensitivity to any of the drugs.

Nanoparticle-based drug delivery systems: promising approaches against infections

International Nuclear Information System (INIS)

Ranghar, Shweta; Sirohi, Parul; Verma, Pritam; Agarwal, Vishnu

2014-01-01

Despite the fact that many new drugs and technologies have been developed to combat the infectious diseases, these have continued to be global health challenges. The use of conventional antimicrobial agents against these infections is always associated with problems such as the development of multiple drug resistance and adverse side effects. In addition, the inefficient traditional drug delivery system results in inadequate therapeutic index, low bioavailability of drugs and many other limitations. In this regard, antimicrobial nanoparticles and nanosized drug delivery carriers have emerged as potent effective agents against the infections. Nanoparticles have unique properties owing to their ultra small and controllable size such as high surface area, enhanced reactivity, and functionalizable structure. This review focused on different classes of antimicrobial nanoparticles, including metal, metal oxide and others along with their mechanism of action and their potential use against the infections. The review also focused on the development of nanoparticle systems for antimicrobial drug delivery and use of these systems for delivery of various antimicrobial agents, giving an overview about modern nanoparticle based therapeutic strategies against the infections. (author)

Nanoparticle-based drug delivery systems: promising approaches against infections

Energy Technology Data Exchange (ETDEWEB)

Ranghar, Shweta; Sirohi, Parul [Department of Applied Mechanics, Motilal Nehru National Institute of Technology, Allahabad (India); Verma, Pritam; Agarwal, Vishnu [Department of Biotechnology, Motilal Nehru National Institute of Technology, Allahabad (India)

2014-03-15

Despite the fact that many new drugs and technologies have been developed to combat the infectious diseases, these have continued to be global health challenges. The use of conventional antimicrobial agents against these infections is always associated with problems such as the development of multiple drug resistance and adverse side effects. In addition, the inefficient traditional drug delivery system results in inadequate therapeutic index, low bioavailability of drugs and many other limitations. In this regard, antimicrobial nanoparticles and nanosized drug delivery carriers have emerged as potent effective agents against the infections. Nanoparticles have unique properties owing to their ultra small and controllable size such as high surface area, enhanced reactivity, and functionalizable structure. This review focused on different classes of antimicrobial nanoparticles, including metal, metal oxide and others along with their mechanism of action and their potential use against the infections. The review also focused on the development of nanoparticle systems for antimicrobial drug delivery and use of these systems for delivery of various antimicrobial agents, giving an overview about modern nanoparticle based therapeutic strategies against the infections. (author)

Biofilm disruption with rotating microrods enhances antimicrobial efficacy

Energy Technology Data Exchange (ETDEWEB)

Mair, Lamar O., E-mail: Lamar.Mair@gmail.com [Weinberg Medical Physics, Inc., North Bethesda, MD (United States); Nacev, Aleksandar; Hilaman, Ryan; Stepanov, Pavel Y.; Chowdhury, Sagar; Jafari, Sahar [Weinberg Medical Physics, Inc., North Bethesda, MD (United States); Hausfeld, Jeffrey [School of Medicine and Health Sciences, George Washington University, WA (United States); Karlsson, Amy J. [Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD (United States); Shirtliff, Mark E. [School of Dentistry, University of Maryland, Baltimore, MD (United States); Shapiro, Benjamin [Fischell Department of Bioengineering, University of Maryland, College Park, MD (United States); Weinberg, Irving N. [Weinberg Medical Physics, Inc., North Bethesda, MD (United States)

2017-04-01

Biofilms are a common and persistent cause of numerous illnesses. Compared to planktonic microbes, biofilm residing cells often demonstrate significant resistance to antimicrobial agents. Thus, methods for dislodging cells from the biofilm may increase the antimicrobial susceptibility of such cells, and serve as a mechanical means of increasing antimicrobial efficacy. Using Aspergillus fumigatus as a model microbe, we magnetically rotate microrods in and around biofilm. We show that such rods can improve the efficacy of antimicrobial Amphotericin B treatments in vitro. This work represents a first step in using kinetic magnetic particle therapy for disrupting fungal biofilms. - Highlights: • Fungal biofilms have been implicated in a variety of medical ailments. • Magnetic microrods, grown via electroplating, were rotated in and around fungal biofilms. • Rotating microrods potentiate the effectiveness of antimicrobial drug. • Antimicrobial efficacy may be enhanced due to increased mixing.

Biofilm disruption with rotating microrods enhances antimicrobial efficacy

International Nuclear Information System (INIS)

Mair, Lamar O.; Nacev, Aleksandar; Hilaman, Ryan; Stepanov, Pavel Y.; Chowdhury, Sagar; Jafari, Sahar; Hausfeld, Jeffrey; Karlsson, Amy J.; Shirtliff, Mark E.; Shapiro, Benjamin; Weinberg, Irving N.

2017-01-01

Biofilms are a common and persistent cause of numerous illnesses. Compared to planktonic microbes, biofilm residing cells often demonstrate significant resistance to antimicrobial agents. Thus, methods for dislodging cells from the biofilm may increase the antimicrobial susceptibility of such cells, and serve as a mechanical means of increasing antimicrobial efficacy. Using Aspergillus fumigatus as a model microbe, we magnetically rotate microrods in and around biofilm. We show that such rods can improve the efficacy of antimicrobial Amphotericin B treatments in vitro. This work represents a first step in using kinetic magnetic particle therapy for disrupting fungal biofilms. - Highlights: • Fungal biofilms have been implicated in a variety of medical ailments. • Magnetic microrods, grown via electroplating, were rotated in and around fungal biofilms. • Rotating microrods potentiate the effectiveness of antimicrobial drug. • Antimicrobial efficacy may be enhanced due to increased mixing.

Cyclodextrins: A Weapon in the Fight Against Antimicrobial Resistance

Science.gov (United States)

Wong, Chew Ee; Dolzhenko, Anton V.; Lee, Sui Mae; Young, David James

Antimicrobial resistance poses one of the most serious global challenges of our age. Cyclodextrins (CDs) are widely utilized excipients in formulations because of their solubilizing properties, low toxicity, and low inflammatory response. This review summarizes recent investigations of antimicrobial agents involving CDs and CD-based antimicrobial materials. CDs have been employed for antimicrobial applications either through formation of inclusion complexes or by chemical modification of their hydroxyl groups to tailor pharmaceutically active compounds. Applications of these CD inclusion complexes include drug delivery, antimicrobial coatings on materials (e.g., biomedical devices and implants) and antimicrobial dressings that help to prevent wound infections. There are relatively limited studies of chemically modified CDs with antimicrobial activity. The mechanism of action of antimicrobial CD inclusion complexes and derivatives needs further elucidation, but activity of CDs and their derivatives is often associated with their interaction with bacterial cell membranes.

In vitro antimicrobial and phytochemical properties of crude extract ...

African Journals Online (AJOL)

STORAGESEVER

2008-10-20

Oct 20, 2008 ... University of Fort Hare, Alice 5700, South Africa. 2Department of Microbiology, Obafemi Awolowo .... Thus improvement on such extract by pharmaceutical industry to produce antimicrobial drug of ... Table 1. Antimicrobial activity profile of the crude extract of stem bark of A. africana. Zones of inhibition (mm)*.

Helical Antimicrobial Sulfono- {gamma} -AApeptides

Energy Technology Data Exchange (ETDEWEB)

Li, Yaqiong; Wu, Haifan; Teng, Peng; Bai, Ge; Lin, Xiaoyang; Zuo, Xiaobing; Cao, Chuanhai; Cai, Jianfeng

2015-06-11

Host-defense peptides (HDPs) such as magainin 2 have emerged as potential therapeutic agents combating antibiotic resistance. Inspired by their structures and mechanism of action, herein we report the fi rst example of antimicrobial helical sulfono- γ - AApeptide foldamers. The lead molecule displays broad-spectrum and potent antimicrobial activity against multi-drug-resistant Gram- positive and Gram-negative bacterial pathogens. Time-kill studies and fl uorescence microscopy suggest that sulfono- γ -AApeptides eradicate bacteria by taking a mode of action analogous to that of HDPs. Clear structure - function relationships exist in the studied sequences. Longer sequences, presumably adopting more-de fi ned helical structures, are more potent than shorter ones. Interestingly, the sequence with less helical propensity in solution could be more selective than the stronger helix-forming sequences. Moreover, this class of antimicrobial agents are resistant to proteolytic degradation. These results may lead to the development of a new class of antimicrobial foldamers combating emerging antibiotic-resistant pathogens.

Synthesis and Antimicrobial Activity of Some 2-Amino-4-(7 ...

African Journals Online (AJOL)

The synthesized compounds were investigated for their antimicrobial activity against four bacteria and five fungi by serial plate dilution method using ofloxacin and ketoconazole as reference antimicrobial drugs, respectively, and their minimum inhibitory concentrations (MICs) were determined. Results: Compounds 1 (p ...

Efflux-mediated antimicrobial resistance.

Science.gov (United States)

Poole, Keith

2005-07-01

Antibiotic resistance continues to plague antimicrobial chemotherapy of infectious disease. And while true biocide resistance is as yet unrealized, in vitro and in vivo episodes of reduced biocide susceptibility are common and the history of antibiotic resistance should not be ignored in the development and use of biocidal agents. Efflux mechanisms of resistance, both drug specific and multidrug, are important determinants of intrinsic and/or acquired resistance to these antimicrobials, with some accommodating both antibiotics and biocides. This latter raises the spectre (as yet generally unrealized) of biocide selection of multiple antibiotic-resistant organisms. Multidrug efflux mechanisms are broadly conserved in bacteria, are almost invariably chromosome-encoded and their expression in many instances results from mutations in regulatory genes. In contrast, drug-specific efflux mechanisms are generally encoded by plasmids and/or other mobile genetic elements (transposons, integrons) that carry additional resistance genes, and so their ready acquisition is compounded by their association with multidrug resistance. While there is some support for the latter efflux systems arising from efflux determinants of self-protection in antibiotic-producing Streptomyces spp. and, thus, intended as drug exporters, increasingly, chromosomal multidrug efflux determinants, at least in Gram-negative bacteria, appear not to be intended as drug exporters but as exporters with, perhaps, a variety of other roles in bacterial cells. Still, given the clinical significance of multidrug (and drug-specific) exporters, efflux must be considered in formulating strategies/approaches to treating drug-resistant infections, both in the development of new agents, for example, less impacted by efflux and in targeting efflux directly with efflux inhibitors.

Use of antimicrobial growth promoters in food animals and Enterococcus faecium resistance to therapeutic antimicrobial drugs in Europe

DEFF Research Database (Denmark)

Wegener, Henrik Caspar; Aarestrup, Frank Møller; Jensen, Lars Bogø

1999-01-01

on the Tn1546 transposon. Furthermore, glycopeptide-resistant strains, as well as resistance determinants, can be transmitted from animals to humans. Two antimicrobial classes expected to provide the future therapeutic options for treatment of infections with vancomycin-resistant enterococci have analogues......Supplementing animal feed with antimicrobial agents to enhance growth has been common practice for more than 30 years and is estimated to constitute more than half the total antimicrobial use worldwide. The potential public health consequences of this use have been debated; however, until recently......, clear evidence of a health risk was not available. Accumulating evidence now indicates that the use of the glycopeptide avoparcin as a growth promoter has created in food animals a major reservoir of Enterococcus faecium, which contains the high level glycopeptide resistance determinant vanA, located...

Variation in Outpatient Oral Antimicrobial Use Patterns among Canadian Provinces, 2000 to 2010

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Shiona K Glass-Kaastra

2014-01-01

Full Text Available BACKGROUND: The volume and patterns of antimicrobial drug use are key variables to consider when developing guidelines for prescribing, and programs to address stewardship and combat the increasing prevalence of antimicrobial resistant pathogens. Because drug programs are regulated at the provincial level, there is an expectation that antibiotic use may vary among provinces.

Optimisation of antimicrobial dosing based on pharmacokinetic and pharmacodynamic principles

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Grace Si Ru Hoo

2017-01-01

Full Text Available While suboptimal dosing of antimicrobials has been attributed to poorer clinical outcomes, clinical cure and mortality advantages have been demonstrated when target pharmacokinetic (PK and pharmacodynamic (PD indices for various classes of antimicrobials were achieved to maximise antibiotic activity. Dosing optimisation requires a good knowledge of PK/PD principles. This review serves to provide a foundation in PK/PD principles for the commonly prescribed antibiotics (β-lactams, vancomycin, fluoroquinolones and aminoglycosides, as well as dosing considerations in special populations (critically ill and obese patients. PK principles determine whether an appropriate dose of antimicrobial reaches the intended pathogen(s. It involves the fundamental processes of absorption, distribution, metabolism and elimination, and is affected by the antimicrobial's physicochemical properties. Antimicrobial pharmacodynamics define the relationship between the drug concentration and its observed effect on the pathogen. The major indicator of the effect of the antibiotics is the minimum inhibitory concentration. The quantitative relationship between a PK and microbiological parameter is known as a PK/PD index, which describes the relationship between dose administered and the rate and extent of bacterial killing. Improvements in clinical outcomes have been observed when antimicrobial agents are dosed optimally to achieve their respective PK/PD targets. With the rising rates of antimicrobial resistance and a limited drug development pipeline, PK/PD concepts can foster more rational and individualised dosing regimens, improving outcomes while simultaneously limiting the toxicity of antimicrobials.

Surveillance of antimicrobial resistance at a tertiary hospital in Tanzania

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Mashurano Marcellina

2004-10-01

Full Text Available Abstract Background Antimicrobial resistance is particularly harmful to infectious disease management in low-income countries since expensive second-line drugs are not readily available. The objective of this study was to implement and evaluate a computerized system for surveillance of antimicrobial resistance at a tertiary hospital in Tanzania. Methods A computerized surveillance system for antimicrobial susceptibility (WHONET was implemented at the national referral hospital in Tanzania in 1998. The antimicrobial susceptibilities of all clinical bacterial isolates received during an 18 months' period were recorded and analyzed. Results The surveillance system was successfully implemented at the hospital. This activity increased the focus on antimicrobial resistance issues and on laboratory quality assurance issues. The study identified specific nosocomial problems in the hospital and led to the initiation of other prospective studies on prevalence and antimicrobial susceptibility of bacterial infections. Furthermore, the study provided useful data on antimicrobial patterns in bacterial isolates from the hospital. Gram-negative bacteria displayed high rates of resistance to common inexpensive antibiotics such as ampicillin, tetracycline and trimethoprim-sulfamethoxazole, leaving fluoroquinolones as the only reliable oral drugs against common Gram-negative bacilli. Gentamicin and third generation cephalosporins remain useful for parenteral therapy. Conclusion The surveillance system is a low-cost tool to generate valuable information on antimicrobial resistance, which can be used to prepare locally applicable recommendations on antimicrobial use. The system pinpoints relevant nosocomial problems and can be used to efficiently plan further research. The surveillance system also functions as a quality assurance tool, bringing attention to methodological issues in identification and susceptibility testing.

Trends in Drug Resistance of Acinetobacter baumannii over a 10-year Period: Nationwide Data from the China Surveillance of Antimicrobial Resistance Program.

Science.gov (United States)

Gao, Lei; Lyu, Yuan; Li, Yun

2017-03-20

Acinetobacter baumannii has emerged as an important pathogen causing a variety of infections. Using data from the China Surveillance of Antimicrobial Resistance Program conducted biennially, we investigated the secular changes in the resistance of 2917 isolates of A. baumannii from 2004 to 2014 to differ antimicrobial agents. Pathogen samples were collected from 17 to 20 hospitals located in the eastern, central, and western regions of China. Minimum inhibitory concentrations (MICs) were determined by a 2-fold agar dilution method, and antimicrobial susceptibility was established using the 2014 Clinical Laboratory Standards Institute-approved breakpoints. Isolates not susceptible to all the tested aminoglycosides, fluoroquinolones, β-lactams, β-lactam/β-lactam inhibitors and carbapenems were defined as extensively drug resistant. The rates of nonsusceptibility to common antimicrobial agents remained high (>65%) over the years with some fluctuations to certain agents. The prevalence of imipenem-resistant A. baumannii (IRAB) increased from 13.3% in 2004 to 70.5% in 2014 and that of extensively drug-resistant A. baumannii (XDRAB) increased from 11.1% in 2004 to 60.4% in 2014. The activity of tigecycline was stable with MIC90 ≤4 mg/L against A. baumannii from 2009 to 2014. Susceptibility to colistin remained high (97.0%) from 2009 to 2014. The prevalence of XDRAB increased in all the three surveillance regions over the years and was significantly higher in Intensive Care Unit (ICU) wards than non-ICU wards. This longitudinal multicenter surveillance program revealed the nationwide emergence of A. baumannii in China and showed a significant increase in prevalence from 2004 to 2014. High levels of bacterial resistance were detected among samples collected from clinical settings in China, with IRAB and XDRAB being especially prevalent. This study will help to guide empirical therapy and identify at-risk groups requiring more intense interventional infection control

Antimicrobial resistance mechanisms among Campylobacter.

Science.gov (United States)

Wieczorek, Kinga; Osek, Jacek

2013-01-01

Campylobacter jejuni and Campylobacter coli are recognized as the most common causative agents of bacterial gastroenteritis in the world. Humans most often become infected by ingesting contaminated food, especially undercooked chicken, but also other sources of bacteria have been described. Campylobacteriosis is normally a self-limiting disease. Antimicrobial treatment is needed only in patients with more severe disease and in those who are immunologically compromised. The most common antimicrobial agents used in the treatment of Campylobacter infections are macrolides, such as erythromycin, and fluoroquinolones, such as ciprofloxacin. Tetracyclines have been suggested as an alternative choice in the treatment of clinical campylobacteriosis but in practice are not often used. However, during the past few decades an increasing number of resistant Campylobacter isolates have developed resistance to fluoroquinolones and other antimicrobials such as macrolides, aminoglycosides, and beta-lactams. Trends in antimicrobial resistance have shown a clear correlation between use of antibiotics in the veterinary medicine and animal production and resistant isolates of Campylobacter in humans. In this review, the patterns of emerging resistance to the antimicrobial agents useful in treatment of the disease are presented and the mechanisms of resistance to these drugs in Campylobacter are discussed.

Rationality of Antimicrobial Prescriptions in Community Pharmacy Users.

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Sara I V C Lima

Full Text Available Although there is a conflict between the treatment benefits for a single individual and society, restrictions on antibiotic use are needed to reduce the prevalence of resistance to these drugs, which is the main result of irrational use. Brazil, cataloged as a pharmemerging market, has implemented restrictive measures for the consumption of antibiotics. The objective of this study was to investigate the quality of antimicrobial prescriptions and user knowledge of their treatment with these drugs.A two-stage cross-sectional, combined and stratified survey of pharmacy users holding an antimicrobial prescription was conducted in the community between May and November 2014. A pharmacist analyzed each prescription for legibility and completeness, and applied a structured questionnaire to the users or their caregivers on their knowledge regarding treatment and user sociodemographic data. An estimated 29.3% of prescriptions had one or more illegible items, 91.3% had one or more missing items, and 29.0% had both illegible and missing items. Dosing schedule and patient identification were the most commonly unreadable items in prescriptions, 18.81% and 12.14%, respectively. The lack of complete patient identification occurred in 90.53% of the prescriptions. It is estimated that 40.3% of users have used antimicrobials without prescription and that 46.49% did not receive any guidance on the administration of the drug.Despite the measures taken by health authorities to restrict the misuse of antimicrobials, it was observed that prescribers still do not follow the criteria of current legislation, particularly relating to items needed for completion of the prescription. Moreover, users receive little information about their antimicrobial treatment.

Assessment of berberine as a multi-target antimicrobial: a multi-omics study for drug discovery and repositioning.

Science.gov (United States)

Karaosmanoglu, Kubra; Sayar, Nihat Alpagu; Kurnaz, Isil Aksan; Akbulut, Berna Sariyar

2014-01-01

Postgenomics drug development is undergoing major transformation in the age of multi-omics studies and drug repositioning. Rather than applications solely in personalized medicine, omics science thus additionally offers a better understanding of a broader range of drug targets and drug repositioning. Berberine is an isoquinoline alkaloid found in many medicinal plants. We report here a whole genome microarray study in tandem with proteomics techniques for mining the plethora of targets that are putatively involved in the antimicrobial activity of berberine against Escherichia coli. We found DNA replication/repair and transcription to be triggered by berberine, indicating that nucleic acids, in general, are among its targets. Our combined transcriptomics and proteomics multi-omics findings underscore that, in the presence of berberine, cell wall or cell membrane transport and motility-related functions are also specifically regulated. We further report a general decline in metabolism, as seen by repression of genes in carbohydrate and amino acid metabolism, energy production, and conversion. An involvement of multidrug efflux pumps, as well as reduced membrane permeability for developing resistance against berberine in E. coli was noted. Collectively, these findings offer original and significant leads for omics-guided drug discovery and future repositioning approaches in the postgenomics era, using berberine as a multi-omics case study.

Inferring the interaction structure of resistance to antimicrobials.

Science.gov (United States)

Zawack, Kelson; Love, Will; Lanzas, Cristina; Booth, James G; Gröhn, Yrjö T

2018-04-01

The growth of antimicrobial resistance presents a significant threat to human and animal health. Of particular concern is multi-drug resistance, as this increases the chances an infection will be untreatable by any antibiotic. In order to understand multi-drug resistance, it is essential to understand the association between drug resistances. Pairwise associations characterize the connectivity between resistances and are useful in making decisions about courses of treatment, or the design of drug cocktails. Higher-order associations, interactions, which tie together groups of drugs can suggest commonalities in resistance mechanism and lead to their identification. To capture interactions, we apply log-linear models of contingency tables to analyze publically available data on the resistance of Escheresia coli isolated from chicken and turkey meat by the National Antimicrobial Resistance Monitoring System. Standard large sample and conditional exact testing approaches for assessing significance of parameters in these models breakdown due to structured patterns inherent to antimicrobial resistance. To address this, we adopt a Bayesian approach which reveals that E. coli resistance associations can be broken into two subnetworks. The first subnetwork is characterized by a hierarchy of β-lactams which is consistent across the chicken and turkey datasets. Tier one in this hierarchy is a near equivalency between amoxicillin-clavulanic acid, ceftriaxone and cefoxitin. Susceptibility to tier one then implies susceptibility to ceftiofur. The second subnetwork is characterized by more complex interactions between a variety of drug classes that vary between the chicken and turkey datasets. Copyright © 2018 Elsevier B.V. All rights reserved.

In vitro antimicrobial efficacy of a fixed-dose combination of RHZE against M. tuberculosis

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Vanessa Albertina Agertt

Full Text Available ABSTRACT The use of drugs in fixed-dose combination (FDC is now recommended by the World Health Organization (WHO due to the emergence of multidrug-resistant strains of Mycobacterium tuberculosis. FDC uses different drugs against tuberculosis (TB in a single tablet for phase-intensive therapeutic intervention. This therapy aims to optimize treatment, to prevent inappropriate use of drugs, and to prevent the emergence of new resistant strains. This study aims to evaluate the susceptibility of clinical isolates of M. tuberculosis against rifampicin, isoniazid, ethambutol, and pyrazinamide. The antimicrobials were tested separately and in associations according to FDC. This was used for broth microdilution method, which was compared to the proportions method previously considered as the gold standard. In antimicrobials testing alone, several strains were resistant to one, two, or three drugs. However, when applied to association of drugs in FDC, there was no antimicrobial resistance. The results strengthen the FDC's concept, which aims to unite the four anti-TB drugs to combat bacterial resistance.

Efflux as a mechanism of antimicrobial drug resistance in clinical relevant microorganisms: the role of efflux inhibitors.

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Willers, Clarissa; Wentzel, Johannes Frederik; du Plessis, Lissinda Hester; Gouws, Chrisna; Hamman, Josias Hendrik

2017-01-01

Microbial resistance against antibiotics is a serious threat to the effective treatment of infectious diseases. Several mechanisms exist through which microorganisms can develop resistance against antimicrobial drugs, of which the overexpression of genes to produce efflux pumps is a major concern. Several efflux transporters have been identified in microorganisms, which infer resistance against specific antibiotics and even multidrug resistance. Areas covered: This paper focuses on microbial resistance against antibiotics by means of the mechanism of efflux and gives a critical overview of studies conducted to overcome this problem by combining efflux pump inhibitors with antibiotics. Information was obtained from a literature search done with MEDLINE, Pubmed, Scopus, ScienceDirect, OneSearch and EBSCO host. Expert opinion: Efflux as a mechanism of multidrug resistance has presented a platform for improved efficacy against resistant microorganisms by co-administration of efflux pump inhibitors with antimicrobial agents. Although proof of concept has been shown for this approach with in vitro experiments, further research is needed to develop more potent inhibitors with low toxicity which is clinically effective.

The human gut microbiota as a reservoir for antimicrobial resistance genes

NARCIS (Netherlands)

Bülow, E.

2015-01-01

In the last decades, the emergence and spread of resistant opportunistic pathogens is compromising the effectiveness of antimicrobial therapies. Understanding the emergence and global spread of drug-resistant microorganisms is thus crucial to combat antimicrobial resistance. The human gut harbors a

Antimicrobial stewardship: attempting to preserve a strategic resource

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Trevor Van Schooneveld, Md

2011-07-01

Full Text Available Antimicrobials hold a unique place in our drug armamentarium. Unfortunately the increase in resistance among both gram-positive and gram-negative pathogens coupled with a lack of new antimicrobial agents is threatening our ability to treat infections. Antimicrobial use is the driving force behind this rise in resistance and much of this use is suboptimal. Antimicrobial stewardship programs (ASP have been advocated as a strategy to improve antimicrobial use. The goals of ASP are to improve patient outcomes while minimizing toxicity and selection for resistant strains by assisting in the selection of the correct agent, right dose, and best duration. Two major strategies for ASP exist: restriction/pre-authorization that controls use at the time of ordering and audit and feedback that reviews ordered antimicrobials and makes suggestions for improvement. Both strategies have some limitations, but have been effective at achieving stewardship goals. Other supplemental strategies such as education, clinical prediction rules, biomarkers, clinical decision support software, and institutional guidelines have been effective at improving antimicrobial use. The most effective antimicrobial stewardship programs have employed multiple strategies to impact antimicrobial use. Using these strategies stewardship programs have been able to decrease antimicrobial use, the spread of resistant pathogens, the incidence of C. difficile infection, pharmacy costs, and improved patient outcomes.

ANTIMICROBIAL DRUG RESISTANCE IN STRAINS OF Escherichia coli ISOLATED FROM FOOD SOURCES

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Mohammed Uddin Rasheed

2014-07-01

Full Text Available A variety of foods and environmental sources harbor bacteria that are resistant to one or more antimicrobial drugs used in medicine and agriculture. Antibiotic resistance in Escherichia coli is of particular concern because it is the most common Gram-negative pathogen in humans. Hence this study was conducted to determine the antibiotic sensitivity pattern of E. coli isolated from different types of food items collected randomly from twelve localities of Hyderabad, India. A total of 150 samples comprising; vegetable salad, raw egg-surface, raw chicken, unpasteurized milk, and raw meat were processed microbiologically to isolate E. coli and to study their antibiotic susceptibility pattern by the Kirby-Bauer method. The highest percentages of drug resistance in isolates of E. coli were detected from raw chicken (23.3% followed by vegetable salad (20%, raw meat (13.3%, raw egg-surface (10% and unpasteurized milk (6.7%. The overall incidence of drug resistant E. coli was 14.7%. A total of six (4% Extended Spectrum β-Lactamase (ESBL producers were detected, two each from vegetable salads and raw chicken, and one each from raw egg-surface and raw meat. Multidrug resistant strains of E. coli are a matter of concern as resistance genes are easily transferable to other strains. Pathogen cycling through food is very common and might pose a potential health risk to the consumer. Therefore, in order to avoid this, good hygienic practices are necessary in the abattoirs to prevent contamination of cattle and poultry products with intestinal content as well as forbidding the use of untreated sewage in irrigating vegetables.

Antimicrobials, stress and mutagenesis.

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Alexandro Rodríguez-Rojas

2014-10-01

Full Text Available Cationic antimicrobial peptides are ancient and ubiquitous immune effectors that multicellular organisms use to kill and police microbes whereas antibiotics are mostly employed by microorganisms. As antimicrobial peptides (AMPs mostly target the cell wall, a microbial 'Achilles heel', it has been proposed that bacterial resistance evolution is very unlikely and hence AMPs are ancient 'weapons' of multicellular organisms. Here we provide a new hypothesis to explain the widespread distribution of AMPs amongst multicellular organism. Studying five antimicrobial peptides from vertebrates and insects, we show, using a classic Luria-Delbrück fluctuation assay, that cationic antimicrobial peptides (AMPs do not increase bacterial mutation rates. Moreover, using rtPCR and disc diffusion assays we find that AMPs do not elicit SOS or rpoS bacterial stress pathways. This is in contrast to the main classes of antibiotics that elevate mutagenesis via eliciting the SOS and rpoS pathways. The notion of the 'Achilles heel' has been challenged by experimental selection for AMP-resistance, but our findings offer a new perspective on the evolutionary success of AMPs. Employing AMPs seems advantageous for multicellular organisms, as it does not fuel the adaptation of bacteria to their immune defenses. This has important consequences for our understanding of host-microbe interactions, the evolution of innate immune defenses, and also sheds new light on antimicrobial resistance evolution and the use of AMPs as drugs.

En Route towards European Clinical breakpoints for veterinary antimicrobial susceptibility testing

NARCIS (Netherlands)

Toutain, Pierre Louis; Bousquet-Mélou, Alain; Damborg, Peter; Ferran, Aude A.; Mevius, Dik; Pelligand, Ludovic; Veldman, Kees T.; Lees, Peter

2017-01-01

VetCAST is the EUCAST sub-committee for Veterinary Antimicrobial Susceptibility Testing. Its remit is to define clinical breakpoints (CBPs) for antimicrobial drugs (AMDs) used in veterinary medicine in Europe. This position paper outlines the procedures and reviews scientific options to solve

Use and misuse of antimicrobial drugs in poultry and livestock: Mechanisms of antimicrobial resistance

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Food safety begins on the farm with management practices that contribute to an abundant, safe, and affordable food supply. To attain this goal, antimicrobials have been used in all stages of food animal production in the United States and elsewhere around the world at one time or another. Among fo...

THE ANTIMICROBIAL ACTIVITY OF SOME EXTRACTS OF FERN GAMETOPHYTES

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Ionica Deliu

2013-12-01

Full Text Available The nature freely offers us many resources for health and beauty. The ferns and their therapeutic properties are less exploit in Romania, except Lycopodium clavatum and Equisetum arvense. Some of the fern properties were demonstrated, like antioxidant, antimicrobial, antiviral, antihelmintic properties. Plants are reasonable alternative to synthetic drugs, avoid the side effect and high cost of synthetic drugs production. Also, the drug resistance bacteria can be controlled using plant derived remedies. In this study the antimicrobial effect of methanolic and ethanolic extracts from three fern species were tested. The extracts were gained from gametophytic stage of ferns obtained in vitro. The most obvious effect was observed for Asplenium trichomanes-ramosum extract. The total polyphenols and flavonoids content were established, too.

Antimicrobial and Biophysical Properties of Surfactant Supplemented with an Antimicrobial Peptide for Treatment of Bacterial Pneumonia

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Banaschewski, Brandon J H; Veldhuizen, Edwin J A; Keating, Eleonora; Haagsman, Henk P; Zuo, Yi Y; Yamashita, Cory M; Veldhuizen, Ruud A W

2015-01-01

BACKGROUND: Antibiotic resistant bacterial infections represent an emerging health concern in clinical settings, and a lack of novel developments in the pharmaceutical pipeline is creating a "perfect storm" for multi-drug resistant bacterial infections. Antimicrobial peptides (AMPs) have been

Antimicrobial use in Belgian broiler production.

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Persoons, Davy; Dewulf, Jeroen; Smet, Annemieke; Herman, Lieve; Heyndrickx, Marc; Martel, An; Catry, Boudewijn; Butaye, Patrick; Haesebrouck, Freddy

2012-08-01

The use of antimicrobials in production animals has become a worldwide concern in the face of rising resistance levels in commensal, pathogenic and zoonotic bacteria. In the years 2007 and 2008 antimicrobial consumption records were collected during two non consecutive production cycles in 32 randomly selected Belgian broiler farms. Antimicrobials were used in 48 of the 64 monitored production cycles, 7 farms did not use any antimicrobials in both production cycles, 2 farms only administered antimicrobials in one of the two production cycles, the other 23 farms applied antimicrobial treatment in both production cycles. For the quantification of antimicrobial drug use, the treatment incidences (TI) based on the defined daily doses (the dose as it should be applied: DDD) and used daily doses (the actual dose applied: UDD) were calculated. A mean antimicrobial treatment incidence per 1000 animals of 131.8 (standard deviation 126.8) animals treated daily with one DDD and 121.4 (SD 106.7) animals treated daily with one UDD was found. The most frequently used compounds were amoxicillin, tylosin and trimethoprim-sulphonamide with a mean TI(UDD) of 37.9, 34.8, and 21.7, respectively. The ratio of the UDD/DDD gives an estimate on correctness of dosing. Tylosin was underdosed in most of the administrations whereas amoxicillin and trimethoprim-sulphonamide were slightly overdosed in the average flock. Copyright © 2012 Elsevier B.V. All rights reserved.

Monte Carlo Simulations Suggest Current Chlortetracycline Drug-Residue Based Withdrawal Periods Would Not Control Antimicrobial Resistance Dissemination from Feedlot to Slaughterhouse.

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Cazer, Casey L; Ducrot, Lucas; Volkova, Victoriya V; Gröhn, Yrjö T

2017-01-01

Antimicrobial use in beef cattle can increase antimicrobial resistance prevalence in their enteric bacteria, including potential pathogens such as Escherichia coli . These bacteria can contaminate animal products at slaughterhouses and cause food-borne illness, which can be difficult to treat if it is due to antimicrobial resistant bacteria. One potential intervention to reduce the dissemination of resistant bacteria from feedlot to consumer is to impose a withdrawal period after antimicrobial use, similar to the current withdrawal period designed to prevent drug residues in edible animal meat. We investigated tetracycline resistance in generic E. coli in the bovine large intestine during and after antimicrobial treatment by building a mathematical model of oral chlortetracycline pharmacokinetics-pharmacodynamics and E. coli population dynamics. We tracked three E. coli subpopulations (susceptible, intermediate, and resistant) during and after treatment with each of three United States chlortetracycline indications (liver abscess reduction, disease control, disease treatment). We compared the proportion of resistant E. coli before antimicrobial use to that at several time points after treatment and found a greater proportion of resistant enteric E. coli after the current withdrawal periods than prior to treatment. In order for the proportion of resistant E. coli in the median beef steer to return to the pre-treatment level, withdrawal periods of 15 days after liver abscess reduction dosing (70 mg daily), 31 days after disease control dosing (350 mg daily), and 36 days after disease treatment dosing (22 mg/kg bodyweight for 5 days) are required in this model. These antimicrobial resistance withdrawal periods would be substantially longer than the current U.S. withdrawals of 0-2 days or Canadian withdrawals of 5-10 days. One published field study found similar time periods necessary to reduce the proportion of resistant E. coli following chlortetracycline disease

Monte Carlo Simulations Suggest Current Chlortetracycline Drug-Residue Based Withdrawal Periods Would Not Control Antimicrobial Resistance Dissemination from Feedlot to Slaughterhouse

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Casey L. Cazer

2017-09-01

Full Text Available Antimicrobial use in beef cattle can increase antimicrobial resistance prevalence in their enteric bacteria, including potential pathogens such as Escherichia coli. These bacteria can contaminate animal products at slaughterhouses and cause food-borne illness, which can be difficult to treat if it is due to antimicrobial resistant bacteria. One potential intervention to reduce the dissemination of resistant bacteria from feedlot to consumer is to impose a withdrawal period after antimicrobial use, similar to the current withdrawal period designed to prevent drug residues in edible animal meat. We investigated tetracycline resistance in generic E. coli in the bovine large intestine during and after antimicrobial treatment by building a mathematical model of oral chlortetracycline pharmacokinetics-pharmacodynamics and E. coli population dynamics. We tracked three E. coli subpopulations (susceptible, intermediate, and resistant during and after treatment with each of three United States chlortetracycline indications (liver abscess reduction, disease control, disease treatment. We compared the proportion of resistant E. coli before antimicrobial use to that at several time points after treatment and found a greater proportion of resistant enteric E. coli after the current withdrawal periods than prior to treatment. In order for the proportion of resistant E. coli in the median beef steer to return to the pre-treatment level, withdrawal periods of 15 days after liver abscess reduction dosing (70 mg daily, 31 days after disease control dosing (350 mg daily, and 36 days after disease treatment dosing (22 mg/kg bodyweight for 5 days are required in this model. These antimicrobial resistance withdrawal periods would be substantially longer than the current U.S. withdrawals of 0–2 days or Canadian withdrawals of 5–10 days. One published field study found similar time periods necessary to reduce the proportion of resistant E. coli following

Model mass spectrometric study of competitive interactions of antimicrobial bisquaternary ammonium drugs and aspirin with membrane phospholipids

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Vekey K.

2013-03-01

Full Text Available The aim of the study is to reveal molecular mechanisms of possible activity modulation of antimicrobial bis-quaternary ammonium compounds (BQAC and aspirin (ASP through noncovalent competitive complexation under their combined introduction into the model systems with membrane phospholipids. Methods. Binary and triple systems containing either decamethoxinum or ethonium, or thionium and aspirin, as well as dipalmitoyl-phosphatidylcholine (DPPC have been investigated by electrospray ionization mass spectrometry. Results. Basing on the analysis of associates recorded in the mass spectra, the types of nonocovalent complexes formed in the systems studied were determined and the supposed role of the complexation in the BQAC and ASP activity modulation was discussed. The formation of associates of BQAC dications with ASP anion is considered as one of the possible ways of deactivation of ionic forms of the medications. The formation of stable complexes of BQAC with DPPC and ASP with DPPC in binary systems as well as the complexes distribution in triple-components systems BQAC:ASP:DPPC point to the existence of competition between drugs of these two types for the binding to DPPC. Conclusions. The results obtained point to the competitive complexation in the model molecular systems containing the BQAC, aspirin and membrane phospholipids. The observed phenomenon testifies to the possibility of modulating the activity of bisquaternary antimicrobial agents and aspirin under their combined usage, due to the competition between the drugs for binding to the target membrane phospholipid molecules and also due to the formation of stable noncovalent complexes between BQAC and ASP.

Molecular Design, Structures, and Activity of Antimicrobial Peptide-Mimetic Polymers

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Takahashi, Haruko; Palermo, Edmund F.; Yasuhara, Kazuma; Caputo, Gregory A.

2014-01-01

There is an urgent need for new antibiotics which are effective against drug-resistant bacteria without contributing to resistance development. We have designed and developed antimicrobial copolymers with cationic amphiphilic structures based on the mimicry of naturally occurring antimicrobial peptides. These copolymers exhibit potent antimicrobial activity against a broad spectrum of bacteria including methicillin-resistant Staphylococcus aureus with no adverse hemolytic activity. Notably, these polymers also did not result in any measurable resistance development in E. coli. The peptide-mimetic design principle offers significant flexibility and diversity in the creation of new antimicrobial materials and their potential biomedical applications. PMID:23832766

Environmental pollution with antimicrobial agents from bulk drug manufacturing industries in Hyderabad, South India, is associated with dissemination of extended-spectrum beta-lactamase and carbapenemase-producing pathogens.

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Lübbert, Christoph; Baars, Christian; Dayakar, Anil; Lippmann, Norman; Rodloff, Arne C; Kinzig, Martina; Sörgel, Fritz

2017-08-01

High antibiotic and antifungal concentrations in wastewater from anti-infective drug production may exert selection pressure for multidrug-resistant (MDR) pathogens. We investigated the environmental presence of active pharmaceutical ingredients and their association with MDR Gram-negative bacteria in Hyderabad, South India, a major production area for the global bulk drug market. From Nov 19 to 28, 2016, water samples were collected from the direct environment of bulk drug manufacturing facilities, the vicinity of two sewage treatment plants, the Musi River, and habitats in Hyderabad and nearby villages. Samples were analyzed for 25 anti-infective pharmaceuticals with liquid chromatography-tandem mass spectrometry and for MDR Gram-negative bacteria using chromogenic culture media. In addition, specimens were screened with PCR for bla VIM , bla KPC , bla NDM , bla IMP-1 , and bla OXA-48 resistance genes. All environmental specimens from 28 different sampling sites were contaminated with antimicrobials. High concentrations of moxifloxacin, voriconazole, and fluconazole (up to 694.1, 2500, and 236,950 µg/L, respectively) as well as increased concentrations of eight other antibiotics were found in sewers in the Patancheru-Bollaram industrial area. Corresponding microbiological analyses revealed an extensive presence of extended-spectrum beta-lactamase and carbapenemase-producing Enterobacteriaceae and non-fermenters (carrying mainly bla OXA-48 , bla NDM , and bla KPC ) in more than 95% of the samples. Insufficient wastewater management by bulk drug manufacturing facilities leads to unprecedented contamination of water resources with antimicrobial pharmaceuticals, which seems to be associated with the selection and dissemination of carbapenemase-producing pathogens. The development and global spread of antimicrobial resistance present a major challenge for pharmaceutical producers and regulatory agencies.

Mechanistic Basis of Antimicrobial Action of Silver Nanoparticles

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Tikam Chand Dakal

2016-11-01

Full Text Available Multidrug resistance of the pathogenic microorganisms to the antimicrobial drugs has become a major impediment toward successful diagnosis and management of infectious diseases. Recent advancements in nanotechnology-based medicines have opened new horizons for combating multidrug resistance in microorganisms. In particular, the use of silver nanoparticles (AgNPs as a potent antibacterial agent has received much attention. The most critical physico-chemical parameters that affect the antimicrobial potential of AgNPs include size, shape, surface charge, concentration and colloidal state. AgNPs exhibits their antimicrobial potential through multifaceted mechanisms. AgNPs adhesion to microbial cells, penetration inside the cells, ROS and free radical generation, and modulation of microbial signal transduction pathways have been recognized as the most prominent modes of antimicrobial action. On the other side, AgNPs exposure to human cells induces cytotoxicity, genotoxicity and inflammatory response in human cells in a cell-type dependent manner. This has raised concerns regarding use of AgNPs in therapeutics and drug delivery. We have summarized the emerging endeavors that address current challenges in relation to safe use of AgNPs in therapeutics and drug delivery platforms. Based on research done so far, we believe that AgNPs can be engineered so as to increase their efficacy, stability, specificity, biosafety and biocompatibility. In this regard, three perspectives research directions have been suggested that include 1 synthesizing AgNPs with controlled physico-chemical properties, 2 examining microbial development of resistance towards AgNPs, and 3 ascertaining the susceptibility of cytoxicity, genotoxicity, and inflammatory response to human cells upon AgNPs exposure.

A cost-effective smartphone-based antimicrobial susceptibility test reader for drug resistance testing (Conference Presentation)

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Feng, Steve W.; Tseng, Derek; Di Carlo, Dino; Garner, Omai B.; Ozcan, Aydogan

2017-03-01

Antimicrobial susceptibility testing (AST) is commonly used for determining microbial drug resistance, but routine testing, which can significantly reduce the spread of multi-drug resistant organisms, is not regularly performed in resource-limited and field-settings due to technological challenges and lack of trained diagnosticians. We developed a portable cost-effective smartphone-based colorimetric 96-well microtiter plate (MTP) reader capable of automated AST without the need for a trained diagnostician. This system is composed of a smartphone used in conjunction with a 3D-printed opto-mechanical attachment, which holds a set of inexpensive light-emitting-diodes and fiber-optic cables coupled to the 96-well MTP for enabling the capture of the transmitted light through each well by the smartphone camera. Images of the MTP plate are captured at multiple exposures and uploaded to a local or remote server (e.g., a laptop) for automated processing/analysis of the results using a custom-designed smartphone application. Each set of images are combined to generate a high dynamic-range image and analyzed for well turbidity (indicative of bacterial growth), followed by interpretative analysis per plate to determine minimum inhibitory concentration (MIC) and drug susceptibility for the specific bacterium. Results are returned to the originating device within 1 minute and shown to the user in tabular form. We demonstrated the capability of this platform using MTPs prepared with 17 antibiotic drugs targeting Gram-negative bacteria and tested 82 patient isolate MTPs of Klebsiella pneumoniae, achieving well turbidity accuracy of 98.19%, MIC accuracy of 95.15%, and drug susceptibility interpretation accuracy of 99.06%, meeting the FDA defined criteria for AST.

78 FR 14801 - Veterinary Oversight of Antimicrobial Use in Livestock: Impact on Stakeholders; Public Meetings...

Science.gov (United States)

2013-03-07

... antimicrobials in medicated feed or drinking water of food-producing animals. Particular emphasis will be placed... five meetings. FDA is concerned about the risk that antimicrobial resistance poses to public health from the use of medically important antimicrobial drugs in food-producing animals. Over the past...

Antimicrobials and therapeutic decision making: an historical perspective.

Science.gov (United States)

Quintiliani, R; Nightingale, C H

1991-01-01

In an effort to remedy inappropriate and excessive use of antimicrobials and to control costs, most hospitals have developed some type of antimicrobial management program. At Hartford Hospital, our most effective approaches have been those that reduce the chances for physician error, decrease the burden on ancillary services, and encourage short hospital stays. These include automatic correction of dose and dosing intervals of antimicrobials and, if possible, their conversion by pharmacy to cost-effective alternative agents; daily review of patients who are taking the drugs by an antimicrobial team; and replacement of parenteral with oral agents as soon as possible. Physician acceptance of these approaches will require significant changes in traditional prescribing styles and willingness to allow pharmacists to implement the recommendations of therapeutic and medical staff committees.

Herd-level association between antimicrobial use and antimicrobial resistance in bovine mastitis Staphylococcus aureus isolates on Canadian dairy farms.

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Saini, V; McClure, J T; Scholl, D T; DeVries, T J; Barkema, H W

2012-04-01

Surveillance of antimicrobial use and resistance is needed to manage antimicrobial resistance in bacteria. In this study, data were collected on antimicrobial use and resistance in Staphylococcus aureus (n=562), isolated from intramammary infections and (sub)clinical mastitis cases on 89 dairy farms in 4 regions of Canada [Alberta, Ontario, Québec, and the Maritime Provinces (Prince Edward Island, Nova Scotia, and New Brunswick)]. Dairy producers were asked to deposit empty drug containers into specially provided receptacles, and antimicrobial drug use rate was calculated to quantify antimicrobial use. Minimum inhibitory concentrations were determined using the Sensititer bovine mastitis plate system (TREK Diagnostic Systems Inc., Cleveland, OH), containing antimicrobials commonly used for mastitis treatment and control. Multivariable logistic regression models were built to determine herd-level risk factors of penicillin, ampicillin, pirlimycin, penicillin-novobiocin combination, tetracycline and sulfadimethoxine resistance in Staph. aureus isolates. Intramammary administration of the penicillin-novobiocin combination for dry cow therapy was associated with penicillin and ampicillin resistance [odds ratio (OR): 2.17 and 3.10, respectively]. Systemic administration of penicillin was associated with penicillin resistance (OR: 1.63). Intramammary administration of pirlimycin for lactating cow mastitis treatment was associated with pirlimycin resistance as well (OR: 2.07). Average herd parity was associated with ampicillin and tetracycline resistance (OR: 3.88 and 0.02, respectively). Average herd size was also associated with tetracycline resistance (OR: 1.02). Dairy herds in the Maritime region had higher odds of penicillin and lower odds of ampicillin resistance than dairy herds in Québec (OR: 2.18 and 0.19, respectively). Alberta dairy herds had lower odds of ampicillin and sulfadimethoxine resistance than dairy herds in Québec (OR: 0.04 and 0.08, respectively

Current Trend of Antimicrobial Prescription for Oral Implant Surgery Among Dentists in India.

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Datta, Rahul; Grewal, Yasmin; Batth, J S; Singh, Amandeep

2014-12-01

The aim of our study was to evaluate antimicrobial prescription behaviour amongst dentists performing oral implant surgery in India. Dentists performing oral implant surgery from different parts of India were personally approached during various national events such as conferences and academic meetings and information regarding their prescription habits for antimicrobial agents in routine oral implant surgery was collected using a structured questionnaire. Out of a total sample of 332 dentists, 85.5 % prescribed 17 different groups or combinations of antibiotics routinely for oral implant surgery in the normal healthy patient. Majority preferred the peri-operative protocol of drug therapy (72.2 %) with variable and prolonged duration of therapy after surgery, ranging from 3 to 10 days. An antimicrobial mouthwash was routinely prescribed by all the doctors (14.5 %) not in favour of prescribing antimicrobials in a normal healthy patient. Our findings suggest that there is a trend of antimicrobial agent misuse by dentists performing oral implant surgery in India, both in terms of drugs used and the protocols prescribed. The majority of these dentists prescribed a variety of antimicrobial agents for prolonged durations routinely even in the normal, healthy patients.

21 CFR 866.1700 - Culture medium for antimicrobial susceptibility tests.

Science.gov (United States)

2010-04-01

... tests. 866.1700 Section 866.1700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Diagnostic Devices § 866.1700 Culture medium for antimicrobial susceptibility tests. (a) Identification. A culture medium for...

Preparation, characterization and in vitro antimicrobial activity of liposomal ceftazidime and cefepime against Pseudomonas aeruginosa strains

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Torres, Ieda Maria Sapateiro; Bento, Etiene Barbosa; Almeida, Larissa da Cunha; de Sá, Luisa Zaiden Carvalho Martins; Lima, Eliana Martins

2012-01-01

Pseudomonas aeruginosa is an opportunistic microorganism with the ability to respond to a wide variety of environmental changes, exhibiting a high intrinsic resistance to a number of antimicrobial agents. This low susceptibility to antimicrobial substances is primarily due to the low permeability of its outer membrane, efflux mechanisms and the synthesis of enzymes that promote the degradation of these drugs. Cephalosporins, particularty ceftazidime and cefepime are effective against P. aeruginosa, however, its increasing resistance has limited the usage of these antibiotics. Encapsulating antimicrobial drugs into unilamellar liposomes is an approach that has been investigated in order to overcome microorganism resistance. In this study, antimicrobial activity of liposomal ceftazidime and cefepime against P. aeruginosa ATCC 27853 and P. aeruginosa SPM-1 was compared to that of the free drugs. Liposomal characterization included diameter, encapsulation efficiency and stability. Minimum Inhibitory Concentration (MIC) was determined for free and liposomal forms of both drugs. Minimum Bactericidal Concentration (MBC) was determined at concentrations 1, 2 and 4 times MIC. Average diameter of liposomes was 131.88 nm and encapsulation efficiency for cefepime and ceftazidime were 2.29% end 5.77%, respectively. Improved stability was obtained when liposome formulations were prepared with a 50% molar ratio for cholesterol in relation to the phospholipid. MIC for liposomal antibiotics for both drugs were 50% lower than that of the free drug, demonstrating that liposomal drug delivery systems may contribute to increase the antibacterial activity of these drugs. PMID:24031917

Antimicrobial blue light: a drug-free approach for inactivating pathogenic microbes

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Wang, Ying; Dai, Tianhong

2018-02-01

Due to the growing global threat of antibiotic resistance, there is a critical need for the development of alternative therapeutics for infectious diseases. Antimicrobial blue light (aBL), as an innovative non-antibiotic approach, has attracted increasing attention. This paper discussed the basic concepts of aBL and recent findings in the studies of aBL. It is commonly hypothesized that the antimicrobial property of aBL is attributed to the presence of endogenous photosensitizing chromophores in microbial cells, which produce cytotoxic reactive oxygen species upon light irradiation. A wide range of important microbes are found to be susceptible to aBL inactivation. Studies have also shown there exist therapeutic windows where microbes are selectively inactivated by aBL while host cells are preserved. The combination of aBL with some other agents result in synergistically improved antimicrobial efficacy. Future efforts should be exerted on the standardization of study design for evaluating aBL efficacy, further elucidation of the mechanism of action, optimization of the technical parameters, and translation of this technique to clinic.

Investigation of antimicrobial use at a tertiary care hospital in Southern Punjab, Pakistan using WHO methodology.

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Atif, Muhammad; Azeem, Muhammad; Saqib, Anum; Scahill, Shane

2017-01-01

Globally, between 20 to 50% of antimicrobial consumption is inappropriate, causing significant impact on the quality of care, cost of therapy and incidence of adverse drug reactions. The purpose of this study was to investigate the prescribing patterns and utilization of antimicrobials in ten selected wards at Bahawal Victoria Hospital (BVH), Bahawalpur, Punjab, Pakistan. A descriptive cross-sectional study was designed using the World Health Organization (WHO) indicators for antimicrobial use. Standard data collection forms were used in ten wards and the Pharmacy Department at BVH. Antimicrobial utilization patterns in terms of frequency and percentage were also determined. Systematic random sampling techniques were used to collect data from 1,000 prescription records out of 21,115 prescriptions written for the six months January to June 2016. For the hospital indicators, a formulary list or essential medicines list (FL/EML) was available, but standard treatment guidelines (STGs) for infectious diseases was not. The average number of days that key antimicrobials were out of stock was 3.3 days per month. The expenditure on antimicrobials as a percentage of the total medicines costs was 12.2%. For the prescribing indicators, the percentage of hospitalizations with antimicrobial(s) prescribed was 82.3%, and the average number of antimicrobials per hospitalization was 1.4 (SD = 0.6). The average duration of antimicrobial treatment per hospitalization was 5.4 days (SD = 3.2). The average cost of antimicrobials prescribed per hospitalization was USD 5.4 (SD = 6.7). None of the patients who were prescribed antimicrobials, received AM according to the STGs (pneumonia and cesarean section cases). Among the patient-care and supplemental indicators, the average duration of hospital stay of patients who received antimicrobials was 6.4 (SD = 4.3) days. The drug sensitivity testing was almost non-existent, with only 0.24% prescription records having drug

Spectrum of antimicrobial activity associated with ionic colloidal silver.

Science.gov (United States)

Morrill, Kira; May, Kathleen; Leek, Daniel; Langland, Nicole; Jeane, La Deana; Ventura, Jose; Skubisz, Corey; Scherer, Sean; Lopez, Eric; Crocker, Ephraim; Peters, Rachel; Oertle, John; Nguyen, Krystine; Just, Scott; Orian, Michael; Humphrey, Meaghan; Payne, David; Jacobs, Bertram; Waters, Robert; Langland, Jeffrey

2013-03-01

Silver has historically and extensively been used as a broad-spectrum antimicrobial agent. However, the Food and Drug Administration currently does not recognize colloidal silver as a safe and effective antimicrobial agent. The goal of this study was to further evaluate the antimicrobial efficacy of colloidal silver. Several strains of bacteria, fungi, and viruses were grown under multicycle growth conditions in the presence or absence of ionic colloidal silver in order to assess the antimicrobial activity. For bacteria grown under aerobic or anaerobic conditions, significant growth inhibition was observed, although multiple treatments were typically required. For fungal cultures, the effects of ionic colloidal silver varied significantly between different genera. No viral growth inhibition was observed with any strains tested. The study data support ionic colloidal silver as a broad-spectrum antimicrobial agent against aerobic and anaerobic bacteria, while having a more limited and specific spectrum of activity against fungi.

The antimicrobial polymer PHMB enters cells and selectively condenses bacterial chromosomes

DEFF Research Database (Denmark)

Chindera, Kantaraja; Mahato, Manohar; Sharma, Ashwani Kumar

2016-01-01

To combat infection and antimicrobial resistance, it is helpful to elucidate drug mechanism(s) of action. Here we examined how the widely used antimicrobial polyhexamethylene biguanide (PHMB) kills bacteria selectively over host cells. Contrary to the accepted model of microbial membrane disrupti...... to bacterial and mammalian cellular DNA and selectively binds and condenses bacterial chromosomes. Because acquired resistance to PHMB has not been reported, selective chromosome condensation provides an unanticipated paradigm for antimicrobial action that may not succumb to resistance....

Statistical metamodeling for revealing synergistic antimicrobial interactions.

Directory of Open Access Journals (Sweden)

Hsiang Chia Chen

2010-11-01

Full Text Available Many bacterial pathogens are becoming drug resistant faster than we can develop new antimicrobials. To address this threat in public health, a metamodel antimicrobial cocktail optimization (MACO scheme is demonstrated for rapid screening of potent antibiotic cocktails using uropathogenic clinical isolates as model systems. With the MACO scheme, only 18 parallel trials were required to determine a potent antimicrobial cocktail out of hundreds of possible combinations. In particular, trimethoprim and gentamicin were identified to work synergistically for inhibiting the bacterial growth. Sensitivity analysis indicated gentamicin functions as a synergist for trimethoprim, and reduces its minimum inhibitory concentration for 40-fold. Validation study also confirmed that the trimethoprim-gentamicin synergistic cocktail effectively inhibited the growths of multiple strains of uropathogenic clinical isolates. With its effectiveness and simplicity, the MACO scheme possesses the potential to serve as a generic platform for identifying synergistic antimicrobial cocktails toward management of bacterial infection in the future.

Antimicrobial stewardship through telemedicine and its impact on multi-drug resistance.

Science.gov (United States)

Dos Santos, Rodrigo P; Dalmora, Camila H; Lukasewicz, Stephani A; Carvalho, Otávio; Deutschendorf, Caroline; Lima, Raquel; Leitzke, Tiago; Correa, Nilson C; Gambetta, Marcelo V

2018-01-01

Introduction Telemedicine technologies are increasingly being incorporated into infectious disease practice. We aimed to demonstrate the impact of antimicrobial stewardship through telemedicine on bacterial resistance rates. Methods We conducted a quasi-experimental study in a 220-bed hospital in southern Brazil. An antimicrobial stewardship program incorporating the use of telemedicine was implemented. Resistance and antimicrobial consumption rates were determined and analysed using a segmented regression model. Results After the intervention, the rate of appropriate antimicrobial prescription increased from 51.4% at baseline to 81.4%. Significant reductions in the consumption of fluoroquinolones (level change, β = -0.80; P change, β = -0.01; P = 0.98), first-generation cephalosporins (level change, β = -0.91; P change, β = +0.01; P = 0.96), vancomycin (level change, β = -0.47; P = 0.04; trend change, β = +0.17; P = 0.66) and polymyxins (level change, β = -0.15; P = 0.56; trend change, β = -1.75; P change, β = +0.84; P change, β = +0.14; P = 0.41) and cefuroxime (level change, β = +0.21; P = 0.17; trend change, β = +0.66; P = 0.02). A significant decrease in the rate of carbapenem-resistant Acinetobacter spp. isolation (level change, β = +0.66; P = 0.01; trend change, β = -1.26; P resistance.

[Antimicrobial susceptibility and drug-resistance genes of Yersinia spp. of retailed poultry in 4 provinces of China].

Science.gov (United States)

Peng, Z X; Zou, M Y; Xu, J; Guan, W Y; Li, Y; Liu, D R; Zhang, S S; Hao, Q; Yan, S F; Wang, W; Yu, D M; Li, F Q

2018-04-06

Objective: To monitor the antimicrobial resistance and drug-resistance genes of Yersinia enterocolitis , Y. intermedia and Y. frederiksenii recovered from retailed fresh poultry of 4 provinces of China. Methods: The susceptibility of 25 isolated Yersinia spp. to 14 classes and 25 kinds of antibiotics was determined by broth microdilution method according to CLSI (Clinical and Laboratory Standards Institute). The antibiotic resistance genes were predicted with antibiotic resistance genes database (ARDB) using whole genome sequences of Yersinia spp. Results: In all 22 Y. enterocolitis tested, 63.7% (14 isolates), 22.8% (5 isolates), 4.6% and 4.6% of 1 isolates exhibited the resistance to cefoxitin, ampicillin-sulbactam, nitrofurantoin and trimethoprim-sulfamethoxazole, respectively. All the 25 isolates were multi-drug resistant to more than 3 antibiotics, while 64.0% of isolates were resistant to more than 4 antibiotics. A few Y. enterocolitis isolates of this study were intermediate to ceftriaxone and ciprofloxacin. Most Yersinia spp. isolates contained antibiotic resistance genes mdtG, ksgA, bacA, blaA, rosAB and acrB , and 5 isolates recovered from fresh chicken also contained dfrA 1, catB 2 and ant 3 ia . Conclusion: The multi-drug resistant Yersinia spp. isolated from retailed fresh poultry is very serious in the 4 provinces of China, and their contained many kinds of drug-resistance genes.

World Health Organization Ranking of Antimicrobials According to Their Importance in Human Medicine: A Critical Step for Developing Risk Management Strategies for the Use of Antimicrobials in Food Production Animals

DEFF Research Database (Denmark)

Collignon, P.; Powers, J. H.; Chiller, T. M.

2009-01-01

stakeholders can use this ranking when developing risk management strategies for the use of antimicrobials in food production animals. The ranking allows stakeholders to focus risk management efforts on drugs used in food animals that are the most important to human medicine and, thus, need to be addressed......The use of antimicrobials in food animals creates an important source of antimicrobial-resistant bacteria that can spread to humans through the food supply. Improved management of the use of antimicrobials in food animals, particularly reducing the usage of those that are "critically important...

An overview of antimicrobial peptides and the latest advances in their development.

Science.gov (United States)

Sierra, Josep M; Fusté, Ester; Rabanal, Francesc; Vinuesa, Teresa; Viñas, Miguel

2017-06-01

The recent dramatic increase in the incidence of antimicrobial resistance has been recognized by organizations such as the United Nations and World Health Organization as well as the governments of the USA and several European countries. A relatively new weapon in the fight against severe infections caused by multi-drug resistant bacteria is antimicrobial peptides (AMPs). These include colistin, currently regarded as the last line of antimicrobial therapy against multi-drug resistant microorganisms. Areas covered: Here, the authors provide an overview of the current research on AMPs. The focus is AMPs currently being developed for the treatment of recalcitrant bacterial infections, the synergies of AMPs and antibiotics, and the activity of AMPs against biofilm. This review also includes a brief introduction into the use of AMPs in infections caused by Mycobacterium, fungi, and parasites. Expert opinion: In research into new antimicrobials, AMPs are gaining increasing attention. While many are natural and are produced by a wide variety of organisms, others are being newly designed and chemically synthesized in the laboratory to achieve novel antimicrobial agents. The same strategy to fight infections in nature is thus being effectively exploited to safeguard human and animal health.

Antimicrobial resistance in the 21st century: a multifaceted challenge.

Science.gov (United States)

Nolte, O

2014-04-01

Antimicrobial resistance, the ability of (pathogenic) bacteria to withstand the action of antibiotic drugs, has recently been rated of having an impact on humans similar to that of global climate change. Indeed, during the last years medicine has faced the development of highly resistant bacterial strains, which were, as a consequence of worldwide travel activity, dispersed all over the globe. This is even more astonishing if taking into account that antibiotics were introduced into human medicine not even hundred years ago. Resistance covers different principle aspects, natural resistance, acquired resistance and clinical resistance. In the modern microbiology laboratory, antimicrobial resistance is determined by measuring the susceptibility of micro-organisms in vitro in the presence of antimicrobials. However, since the efficacy of an antibiotic depends on its pharmacokinetic and pharmacodynamics properties, breakpoints are provided to translate minimal inhibitory concentration to categorical efficacy (i.e. susceptible or resistant). Resistance in one microorganism against one particular drug may drive treatment decisions of clinicians, thereby fostering selection pressure to resistance development against another antibiotic. Thereby, bacteria may acquire more and more resistance traits, ending up with multi-resistance. To this end, antimicrobial resistance becomes a public health concern, not only in terms of limited treatment options but also due to its economic burden. The current paper provides a summary of the main topics associated with antimicrobial resistance as an introduction to this special issue.

Use of antibacterial drugs in Jesenice General hospital in years 1998 to 2004

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Brigita Mavsar-Najdenov

2007-11-01

Full Text Available Background: Continuous monitoring of drug consumption is an important strategy for prudent and cost-effective use of drugs. Antimicrobials are among the most prescribed drugs in outpatient practice and in hospital care. In most cases antimicrobials are improperly prescribed or are even misused. Irrational use of antimicrobials is clinically ineffective and leads to higher treatment costs. Clinical ineffectiveness due to irrational use additionally leads to loss of confidence in antimicrobial drugs, unnecessary exposure of patients and development of antimicrobial resistance. Antimicrobial resistance has become a major global health problem as it presents an imperative for development of new potent antimicrobials which are necessarily associated with markedly higher treatment costs.Material and methods: This survey was focused on rational prescribing of antimicrobial drugs. The data on consumption of antimicrobials for various clinical departments of the Jesenice General Hospital were collected by the hospital pharmacy. WHO ATC 2005 classification system, which ranks antimicrobials in a large group J01: drugs for systemic treatment of bacterial infections and Defined Daily Dose as a measuring unit according to the WHO ATC/DDD methodology was used. Antimicrobial use at the Jesenice General Hospital in the period between 1998 and 2004 was estimated by the Department of Infectious Diseases, Medical Centre Ljubljana as a part of European Surveillance on Antibiotic Consumption project (ESAC. Statistical part of survey was performed by the Chair of Biopharmaceutics and Pharmacokinetics, Faculty of Pharmacy, University of Ljubljana.Results: After year 2000 a trend of decrease in antimicrobial consumption was observed. Compared to European Surveillance on Antibiotic Consumption results in the year 2003 higher usage of penicillins with extended spectrum, fluoroquinolones and 3rd generation cephalosporins in Slovenian hospitals was estimated. These three

Antimicrobial susceptibility among clinical Nocardia species identified by multilocus sequence analysis.

Science.gov (United States)

McTaggart, Lisa R; Doucet, Jennifer; Witkowska, Maria; Richardson, Susan E

2015-01-01

Antimicrobial susceptibility patterns of 112 clinical isolates, 28 type strains, and 9 reference strains of Nocardia were determined using the Sensititre Rapmyco microdilution panel (Thermo Fisher, Inc.). Isolates were identified by highly discriminatory multilocus sequence analysis and were chosen to represent the diversity of species recovered from clinical specimens in Ontario, Canada. Susceptibility to the most commonly used drug, trimethoprim-sulfamethoxazole, was observed in 97% of isolates. Linezolid and amikacin were also highly effective; 100% and 99% of all isolates demonstrated a susceptible phenotype. For the remaining antimicrobials, resistance was species specific with isolates of Nocardia otitidiscaviarum, N. brasiliensis, N. abscessus complex, N. nova complex, N. transvalensis complex, N. farcinica, and N. cyriacigeorgica displaying the traditional characteristic drug pattern types. In addition, the antimicrobial susceptibility profiles of a variety of rarely encountered species isolated from clinical specimens are reported for the first time and were categorized into four additional drug pattern types. Finally, MICs for the control strains N. nova ATCC BAA-2227, N. asteroides ATCC 19247(T), and N. farcinica ATCC 23826 were robustly determined to demonstrate method reproducibility and suitability of the commercial Sensititre Rapmyco panel for antimicrobial susceptibility testing of Nocardia spp. isolated from clinical specimens. The reported values will facilitate quality control and standardization among laboratories. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Evaluation of Antimicrobial Activity of Root Extracts of Abitulon indicum

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Krishna Rao MORTHA

2015-06-01

Full Text Available Antimicrobial activity of Abitulon indicum roots was studied against seven pathogenic bacteria and three fungal strains by agar well diffusion method. Antimicrobial activity was recorded for hexane, chloroform, methanol, ethanol and aqueous extracts. Alcohol (ethanol and methanol extracts exhibited the highest degree of antimicrobial activity compared to aqueous, chloroform and hexane extracts. Pseudomonas aeruginosa was turned out to be the most susceptible bacterium to the crude root chemical constituents, using the standard Tetracycline and Clotrimazole. Minimum inhibition concentration values of hexane, chloroform, methanol, ethanol and aqueous extracts were determined by the agar dilution method and ranged between 62.5 and 1,000 µg. The study suggested that the root extracts possess bioactive compounds with antimicrobial activity against the tested bacteria and fungi, revealing a significant scope to develop a novel broad spectrum of antimicrobial drug formulation from Abitulon indicum.

Antimicrobial Activity of Actinomycetes Against Multidrug Resistant ...

African Journals Online (AJOL)

Antimicrobial Activity of Actinomycetes Against Multidrug Resistant Staphylococcus aureus, E. coli and Various Other Pathogens. ... Purpose: The rapid emergence of drug resistance among pathogenic bacteria, especially multidrugresistant bacteria, underlines the need to look for new antibiotics. Methods: In the present ...

ANTIMICROBIAL ACTIVITY OF “DUTSEN DAN LIBYA”

African Journals Online (AJOL)

DJFLEX

the test organisms showed the lowest MIC at the dose level of 1.25mg/ml and MBC at the dose level of 2.50mg/ ... KEYWORDS: Antimicrobial, Infectious disease, Pathogenic, Bacteria, Fungi ... poverty and increasing incidence of multiple drug.

Eight-Year Surveillance of Antimicrobial Resistance among Enterobacter Cloacae Isolated in the First Bethune Hospital

Science.gov (United States)

Zhou, Qi; Zhang, Man; Wang, Ailin; Xu, Jiancheng; Yuan, Ye

This study was to investigate the antimicrobial resistance of Enterobacter cloacae isolated in 8 consecutive years in the First Bethune Hospital. Disk diffusion test was used to study the antimicrobial resistance. The data were analyzed by WHONET 5 software according to Clinical and Laboratory Standards Institute (CLSI). Most of 683 strains of Enterobacter cloacae were collected from sputum 410 (60.0%), secretions and pus 105 (15.4%), urine 69 (10.1%) during the past 8 years. No Enterobacter cloacae was resistant to imipenem and meropenem in the First Bethune Hospital. The antimicrobial resistance of Enterobacter cloacae had increased in recent 8 years. The change of the antimicrobial resistance should be investigated in order to direct rational drug usage in the clinic and prevent bacterial strain of drug resistance from b eing transmitted.

Bacterial strategies of resistance to antimicrobial peptides.

Science.gov (United States)

Joo, Hwang-Soo; Fu, Chih-Iung; Otto, Michael

2016-05-26

Antimicrobial peptides (AMPs) are a key component of the host's innate immune system, targeting invasive and colonizing bacteria. For successful survival and colonization of the host, bacteria have a series of mechanisms to interfere with AMP activity, and AMP resistance is intimately connected with the virulence potential of bacterial pathogens. In particular, because AMPs are considered as potential novel antimicrobial drugs, it is vital to understand bacterial AMP resistance mechanisms. This review gives a comparative overview of Gram-positive and Gram-negative bacterial strategies of resistance to various AMPs, such as repulsion or sequestration by bacterial surface structures, alteration of membrane charge or fluidity, degradation and removal by efflux pumps.This article is part of the themed issue 'Evolutionary ecology of arthropod antimicrobial peptides'. © 2016 The Author(s).

In Vivo, In Vitro, and In Silico Characterization of Peptoids as Antimicrobial Agents

DEFF Research Database (Denmark)

Czyzewski, Ann M.; Jenssen, Håvard; Fjell, Christopher D.

2016-01-01

report a new QSAR model that we developed based on 27 diverse peptoid sequences, which accurately correlates antimicrobial peptoid structure with antimicrobial activity. We have identified a number of peptoids that have potent, broad-spectrum in vitro activity against multi-drug resistant bacterial......Bacterial resistance to conventional antibiotics is a global threat that has spurred the development of antimicrobial peptides (AMPs) and their mimetics as novel anti-infective agents. While the bioavailability of AMPs is often reduced due to protease activity, the non-natural structure of AMP...... potential of peptoids as antimicrobial agents....

Antimicrobial Lemongrass Essential Oil—Copper Ferrite Cellulose Acetate Nanocapsules

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Ioannis L. Liakos

2016-04-01

Full Text Available Cellulose acetate (CA nanoparticles were combined with two antimicrobial agents, namely lemongrass (LG essential oil and Cu-ferrite nanoparticles. The preparation method of CA nanocapsules (NCs, with the two antimicrobial agents, was based on the nanoprecipitation method using the solvent/anti-solvent technique. Several physical and chemical analyses were performed to characterize the resulting NCs and to study their formation mechanism. The size of the combined antimicrobial NCs was found to be ca. 220 nm. The presence of Cu-ferrites enhanced the attachment of LG essential oil into the CA matrix. The magnetic properties of the combined construct were weak, due to the shielding of Cu-ferrites from the polymeric matrix, making them available for drug delivery applications where spontaneous magnetization effects should be avoided. The antimicrobial properties of the NCs were significantly enhanced with respect to CA/LG only. This work opens novel routes for the development of organic/inorganic nanoparticles with exceptional antimicrobial activities.

Antimicrobial Lemongrass Essential Oil-Copper Ferrite Cellulose Acetate Nanocapsules.

Science.gov (United States)

Liakos, Ioannis L; Abdellatif, Mohamed H; Innocenti, Claudia; Scarpellini, Alice; Carzino, Riccardo; Brunetti, Virgilio; Marras, Sergio; Brescia, Rosaria; Drago, Filippo; Pompa, Pier Paolo

2016-04-20

Cellulose acetate (CA) nanoparticles were combined with two antimicrobial agents, namely lemongrass (LG) essential oil and Cu-ferrite nanoparticles. The preparation method of CA nanocapsules (NCs), with the two antimicrobial agents, was based on the nanoprecipitation method using the solvent/anti-solvent technique. Several physical and chemical analyses were performed to characterize the resulting NCs and to study their formation mechanism. The size of the combined antimicrobial NCs was found to be ca. 220 nm. The presence of Cu-ferrites enhanced the attachment of LG essential oil into the CA matrix. The magnetic properties of the combined construct were weak, due to the shielding of Cu-ferrites from the polymeric matrix, making them available for drug delivery applications where spontaneous magnetization effects should be avoided. The antimicrobial properties of the NCs were significantly enhanced with respect to CA/LG only. This work opens novel routes for the development of organic/inorganic nanoparticles with exceptional antimicrobial activities.

The quest for optimal antimicrobial therapy

NARCIS (Netherlands)

Mol, Petrus Gerardus Maria

2005-01-01

Since the discovery of sulphonam ides and penicillin in the 1930's, and their widespread use in clinical practice during World War II a plethora of new antimicrobial agents have entered the market. Initial optim ism has faded that these new drugs would eliminate infectious diseases as killer

Discovery of antimicrobial compounds targeting bacterial type FAD synthetases.

Science.gov (United States)

Sebastián, María; Anoz-Carbonell, Ernesto; Gracia, Begoña; Cossio, Pilar; Aínsa, José Antonio; Lans, Isaías; Medina, Milagros

2018-12-01

The increase of bacterial strains resistant to most of the available antibiotics shows a need to explore novel antibacterial targets to discover antimicrobial drugs. Bifunctional bacterial FAD synthetases (FADSs) synthesise the flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). These cofactors act in vital processes as part of flavoproteins, making FADS an essential enzyme. Bacterial FADSs are potential antibacterial targets because of differences to mammalian enzymes, particularly at the FAD producing site. We have optimised an activity-based high throughput screening assay targeting Corynebacterium ammoniagenes FADS (CaFADS) that identifies inhibitors of its different activities. We selected the three best high-performing inhibitors of the FMN:adenylyltransferase activity (FMNAT) and studied their inhibition mechanisms and binding properties. The specificity of the CaFADS hits was evaluated by studying also their effect on the Streptococcus pneumoniae FADS activities, envisaging differences that can be used to discover species-specific antibacterial drugs. The antimicrobial effect of these compounds was also evaluated on C. ammoniagenes, S. pneumoniae, and Mycobacterium tuberculosis cultures, finding hits with favourable antimicrobial properties.

A comparative study on the cost of new antibiotics and drugs of other therapeutic categories.

Science.gov (United States)

Falagas, Matthew E; Fragoulis, Konstantinos N; Karydis, Ioannis

2006-12-20

Drug treatment is becoming more expensive due to the increased cost for the introduction of new drugs, and there seems to be an uneven distribution of medication cost for different therapeutic categories. We hypothesized that the cost of new antimicrobial agents may differ from that of other therapeutic categories and this may play a role in the stagnation of development of new antibiotics. We performed a pharmaco-economical comparative analysis of the drug cost of treatment for new agents introduced in the United States drug market in various therapeutic categories. We calculated the drug cost (in US dollars) of a ten-day treatment of all new drugs approved by the FDA during the period between January 1997 and July 2003, according to the 2004 Red Book Pharmacy's Fundamental Reference. New anti-neoplastic agents were found to be the most expensive drugs in comparison to all other therapeutic categories, with a median ten-day drug-treatment cost of US$848 compared to the median ten-day drug-treatment costs of all other categories ranging from US$29 to US$301. On the other hand, new antimicrobial drugs were found to be much less expensive, with a median ten-day drug-treatment cost of US$137 and $US85 for all anti-microbial agents and for anti-microbial agents excluding anti-HIV medications, respectively. The drug-treatment cost of new medications varies considerably by different therapeutic categories. This fact may influence industry decisions regarding the development of new drugs and may play a role in the shortage of new antimicrobial agents in the fight against the serious problem of antimicrobial resistance.

Haemophilus paragallinarum in chickens in Indonesia: III. Antimicrobial drug sensitivity test ofHaemophilus paragallinarum from chickens suffering of coryza

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Sri Poernomo

1998-12-01

Full Text Available An agar disc diffusion method was used to examine the sensitivity of 27 Haemophilus paragallinarum (Hpg isolates consisted of 23 local isolates, 4 standard isolates (serotype A and Escherichia coli ATCC 24922 as a control to eight antimicrobial drugs (ampicillin, erythromycin, oxytetracycline, doxycycline, neomycin, streptomycin, colistine and sulphanlethoxazole-trimethoprim . Twenty one out of 23 local isolates of Hpg were sensitive to doxycycline, 19 isolates to ampsllin, 18 isolates to oxytetracycline, 17 isolates to sulphametoxazole-trimethoprim, 16 isolates to erythromycin, and 13 isolates to neomycin, while 13 isolates were resistance to colistine and 11 isolates were also resistance to streptomycin .

Synthesis and antimicrobial activity of some 2 ...

African Journals Online (AJOL)

These compounds were investigated for their antimicrobial activity against ten bacteria and five fungi by serial plate dilution method using standard drugs, namely, ofloxacin and ketoconazole, respectively, and their minimum inhibitory concentrations (MICs) were also determined. Results: A total of eighteen new compounds ...

Application of firefly luciferase assay for adenosine triphosphate (ATP) to antimicrobial drug sensitivity testing

Science.gov (United States)

Picciolo, G. L.; Tuttle, S. A.; Schrock, C. G.; Deming, J. W.; Barza, M. J.; Wienstein, L.; Chappelle, E. W.

1977-01-01

The development of a rapid method for determining microbial susceptibilities to antibiotics using the firefly luciferase assay for adenosine triphosphate (ATP) is documented. The reduction of bacterial ATP by an antimicrobial agent was determined to be a valid measure of drug effect in most cases. The effect of 12 antibiotics on 8 different bacterial species gave a 94 percent correlation with the standard Kirby-Buer-Agar disc diffusion method. A 93 percent correlation was obtained when the ATP assay method was applied directly to 50 urine specimens from patients with urinary tract infections. Urine samples were centrifuged first to that bacterial pellets could be suspended in broth. No primary isolation or subculturing was required. Mixed cultures in which one species was predominant gave accurate results for the most abundant organism. Since the method is based on an increase in bacterial ATP with time, the presence of leukocytes did not interfere with the interpretation of results. Both the incubation procedure and the ATP assays are compatible with automation.

Antimicrobial Stewardship for a Geriatric Behavioral Health Population

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Kristen Ellis

2016-01-01

Full Text Available Antimicrobial resistance is a growing public health concern. Antimicrobial stewardship and multi-disciplinary intervention can prevent inappropriate antimicrobial use and improve patient care. Special populations, especially older adults and patients with mental health disorders, can be particularly in need of such intervention. The purpose of this project was to assess the impact of pharmacist intervention on appropriateness of antimicrobial prescribing on a geriatric psychiatric unit (GPU. Patients ≥18 years old prescribed oral antibiotics during GPU admission were included. Antimicrobial appropriateness was assessed pre- and post-pharmacist intervention. During the six-month pre- and post-intervention phase, 63 and 70 patients prescribed antibiotics were identified, respectively. Subjects in the post-intervention group had significantly less inappropriate doses for indication compared to the pre-intervention group (10.6% vs. 23.9%, p = 0.02, and significantly less antibiotics prescribed for an inappropriate duration (15.8% vs. 32.4%, p < 0.01. There were no significant differences for use of appropriate drug for indication or appropriate dose for renal function between groups. Significantly more patients in the post intervention group had medications prescribed with appropriate dose, duration, and indication (51% vs. 66%, p = 0.04. Pharmacist intervention was associated with decreased rates of inappropriate antimicrobial prescribing on a geriatric psychiatric unit.

Antimicrobial Resistance Risks of Cholera Prophylaxis for United Nations Peacekeepers.

Science.gov (United States)

Kunkel, Amber; Lewnard, Joseph A; Pitzer, Virginia E; Cohen, Ted

2017-08-01

More than 5 years after a United Nations peacekeeping battalion introduced cholera to Haiti, over 150,000 peacekeepers continue to be deployed annually from countries where cholera is endemic. The United Nations has thus far declined to provide antimicrobial chemoprophylaxis to peacekeepers, a policy based largely on concerns that the risks of drug resistance generation and spread would outweigh the potential benefits of preventing future cholera importations. In this study, we sought to better understand the relative benefits and risks of cholera chemoprophylaxis for peacekeepers in terms of antibiotic resistance. Using a stochastic model to quantify the potential impact of chemoprophylaxis on importation and transmission of drug-resistant and drug-sensitive Vibrio cholerae , we found that chemoprophylaxis would decrease the probability of cholera importation but would increase the expected number of drug-resistant infections if an importation event were to occur. Despite this potential increase, we found that at least 10 drug-sensitive infections would likely be averted per excess drug-resistant infection under a wide range of assumptions about the underlying prevalence of drug resistance and risk of acquired resistance. Given these findings, policymakers should reconsider whether the potential resistance risks of providing antimicrobial chemoprophylaxis to peacekeepers are sufficient to outweigh the anticipated benefits. Copyright © 2017 American Society for Microbiology.

Performance evaluation of nanoclay enriched anti-microbial hydrogels for biomedical applications

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Sonali Karnik

2016-02-01

Full Text Available A major factor contributing to the failure of orthopedic and orthodontic implants is post-surgical infection. Coating metallic implant surfaces with anti-microbial agents has shown promise but does not always prevent the formation of bacterial biofilms. Furthermore, breakdown of these coatings within the human body can cause release of the anti-microbial drugs in an uncontrolled or unpredictable fashion. In this study, we used a calcium alginate and calcium phosphate cement (CPC hydrogel composite as the base material and enriched these hydrogels with the anti-microbial drug, gentamicin sulfate, loaded within a halloysite nanotubes (HNTs. Our results demonstrate a sustained and extended release of gentamicin from hydrogels enriched with the gentamicin-loaded HNTs. When tested against the gram-negative bacteria, the hydrogel/nanoclay composites showed a pronounced zone of inhibition suggesting that anti-microbial doped nanoclay enriched hydrogels can prevent the growth of bacteria. The release of gentamicin sulfate for a period of five days from the nanoclay-enriched hydrogels would supply anti-microbial agents in a sustained and controlled manner and assist in preventing microbial growth and biofilm formation on the titanium implant surface. A pilot study, using mouse osteoblasts, confirmed that the nanoclay enriched surfaces are also cell supportive as osteoblasts readily, proliferated and produced a type I collagen and proteoglycan matrix.

Antimicrobial storage and antibiotic knowledge in the community: a cross-sectional pilot study in north-western Angola.

Science.gov (United States)

Cortez, Joana; Rosário, Edite; Pires, João E; Taborda Lopes, João; Francisco, Moisés; Vlieghe, Erika; Brito, Miguel

2017-07-01

Antimicrobials are drugs that were once lifesavers and mainly curative. Nowadays their value is increasingly under pressure because of the rapid and worldwide emergence of antimicrobial resistance, which, in low-resource settings, frequently occurs in microorganisms that are likely to be transmitted in the community. This was a cross-sectional pilot study including 102 households within the 10th Health and Demographic Surveillance System round in Dande, Bengo Province, Angola. Of the total 102 households piloted, 79 (77.45%) were urban. Fifty-seven respondents were female (56.44%), and the mean age of the respondents was 39.70±15.35years. Overall, storage of antimicrobials was found in 55/102 households (53.92%). More than 66% of the antimicrobials stored were prescribed by a health professional and the majority of antimicrobials were bought at pharmacies or at a street market. Penicillin and its derivatives, antimalarial drugs, and metronidazole were the antimicrobials most frequently stored. Households with female respondents reported storing any drugs at home more frequently (82.50%; p=0.002) and also storing antimicrobials more frequently (64.91%; p=0.016) as compared to households with male respondents. Reported use of antimicrobials was significantly higher in urban households (60.76%, 48/79) as compared to rural households (30.43%, 7/23) (p=0.010). Overall, 74 of 101 respondents (73.26%) reported having already heard about antibiotics. The common reasons given for their use were cough and other respiratory symptoms, wounds, flu and body muscle pain, fever, bladder complaints, and diarrhoea and/or presumed typhoid fever. Nearly 40% (28/74) of the respondents thought that antibiotics should be stopped as soon as the person does not feel sick anymore. Community interventions for appropriate use of antibiotics should be designed with a special focus on women. This should be done through public awareness campaigns and improving access to reliable medical

Impact of Denmark's ban on antimicrobials for growth promotion.

Science.gov (United States)

Jensen, Helen H; Hayes, Dermot J

2014-06-01

Denmark was among the first countries to ban the use of antimicrobials for growth promotion (AGPs) in animal production through an on-going series of actions and regulations since 1995. In 2010 the Yellow Card scheme was adopted to decrease total antimicrobial consumption in pig production through additional restrictions on pig farmers. The withdrawal of AGPs and other restrictions have reduced total antimicrobial use, but at the same time therapeutic drug use has increased and resistance in key zoonotic bacteria has not decreased. Improved use of vaccines and management practices can help reduce losses especially for weaner pigs, but come with additional costs to producers. Copyright © 2014 Elsevier Ltd. All rights reserved.

Deep Learning Improves Antimicrobial Peptide Recognition.

Science.gov (United States)

Veltri, Daniel; Kamath, Uday; Shehu, Amarda

2018-03-24

Bacterial resistance to antibiotics is a growing concern. Antimicrobial peptides (AMPs), natural components of innate immunity, are popular targets for developing new drugs. Machine learning methods are now commonly adopted by wet-laboratory researchers to screen for promising candidates. In this work we utilize deep learning to recognize antimicrobial activity. We propose a neural network model with convolutional and recurrent layers that leverage primary sequence composition. Results show that the proposed model outperforms state-of-the-art classification models on a comprehensive data set. By utilizing the embedding weights, we also present a reduced-alphabet representation and show that reasonable AMP recognition can be maintained using nine amino-acid types. Models and data sets are made freely available through the Antimicrobial Peptide Scanner vr.2 web server at: www.ampscanner.com. amarda@gmu.edu for general inquiries and dan.veltri@gmail.com for web server information. Supplementary data are available at Bioinformatics online.

Chemical Composition and Antimicrobial Activity of Echinophora spinosa L. (Apiaceae Essential Oil

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Jasmina M. Glamočlija

2011-01-01

Full Text Available The present study was undertaken to investigate the chemical composition and effectiveness of the essential oil isolated from Echinophora spinosa on different bacterial and fungal species. Chemical analysis (GC/MS showed that δ³-carene (60,86 %, α-phellandrene (7,12%, p-cymene (6,22 %, myrcene (4,82 % and β-phellandrene (2,73 % were dominant components in this oil. Essential oil tested showed good antimicrobial activity. Antimicrobial potential of this oil was higher than potential of commercial antimicrobial drugs tested, streptomycin, bifonozole and ketoconazole.

Antimicrobial activities of the leaves and roots of Elaeagnus ...

African Journals Online (AJOL)

AZHAR

2013-11-27

Nov 27, 2013 ... Key words: Elaeagnus umbellata, extracts, fungi, yeast, antibiotic discs. INTRODUCTION. Biological screening is an important step in the evaluation of medicinal ... criminate and repetitive use of antimicrobial drugs. (Shariff ...

Human Health Consequences of Use of Antimicrobial Agents in Aquaculture

DEFF Research Database (Denmark)

Heuer, Ole Eske; Kruse, H.; Grave, K.

2009-01-01

industry in many regions of the world and the widespread, intensive, and often unregulated use of antimicrobial agents in this area of animal production, efforts are needed to prevent development and spread of antimicrobial resistance in aquaculture to reduce the risk to human health....... in aquaculture, several are classified by the World Health Organisation as critically important for use in humans. Occurrence of resistance to these antimicrobial agents in human pathogens severely limits the therapeutic options in human infections. Considering the rapid growth and importance of aquaculture...... gene transfer and reach human pathogens, or drug-resistant pathogens from the aquatic environment may reach humans directly. Horizontal gene transfer may occur in the aquaculture environment, in the food chain, or in the human intestinal tract. Among the antimicrobial agents commonly used...

Changes of Antimicrobial Resistance among Staphylococcus Aureus Isolated in 8 Consecutive Years in the First Bethune Hospital

Science.gov (United States)

Xu, Wei; Zhou, Qi; Yang, Chunguang; Yao, Hanxin; Xu, Jiancheng

This study was to investigate the antimicrobial resistance of Staphylococcus aureus isolated in 8 consecutive years in the First Bethune Hospital. Disk diffusion test was used to study the antimicrobial resistance. The data were analyzed by WHONET 5 software according to Clinical and Laboratory Standards Institute (CLSI). Most of 1469 strains of Staphylococcus aureus were collected from sputum 705 (18.0%), secretions 206 (14.0%), pus 177 (12.0%) during the past 8 years. The rates of methicillin-resistant Staphylococcus aureus (MRSA) were between 50.8% and 83.3% during the past 8 years, respectively. In recent 8 years, the antimicrobial resistance of Staphylococcus aureus had increased. Monitoring the antimicrobial resistance to Staphylococcus aureus should be strengthened. The change of the antimicrobial resistance should be investigated in order to direct rational drug usage in the clinic and prevent bacterial strain of drug resistance from being transmitted.

Drug Pollution from Manufacturing and Antimicrobial Resistance: How Does the European Union Manage the Potential Environmental and Health Risks of Importing Pharmaceutical Active Ingredients From Third Countries?

DEFF Research Database (Denmark)

le Gal, Elodie Jeanine Odette

pollution and anti-micro-bacterial resistance within their own borders by buying and importing drugs manufactured in third countries, such as India and China. With a focus on drug pollution from manufacturing, the goal of this paper is to explore the European drug import safety regime. It intends to better...... and environmental failures. Over the past three decades, the scientific literature has been increasingly reporting case studies on environmental pollution from drug manufacturing, human excretions and improper disposal of unused or expired drug residues in different parts of the world. Active ingredients, which...... are responsible for the biological activity of drugs, have been identified as the main vector of pharmaceutical pollution. Associated with the environmental risk of pharmaceutical pollution in soils and waterways is the predicted risk of antimicrobial resistance (AMR) expected to increase and to dramatically...

Patterns Of Antimicrobial Use For Respiratory Tract Infections In Elderly Patients

International Nuclear Information System (INIS)

Taha, H.M.; Rasheedy, D.; Mahmoud, A.H.

2013-01-01

Background: Elderly patients are prone to respiratory tract infections (RTIs) both; acute bronchitis and pneumonia. A large proportion of the antibiotics prescribed are unlikely to provide clinical benefit to patients. There is an increased need to decrease excess antibiotic use in elderly to minimize antibiotic resistance. Objective: To describe patterns of antimicrobial use for respiratory tract infections (RTIs) among elderly Patients and methods: A cross sectional study was conducted on one hundred elderly patients, aged > 60 years, both males and females to describe patterns of antimicrobial use for respiratory tract infections (RTIs) among elderly patients. RTIs, categorized as acute bronchitis, and pneumonia, were studied for appropriateness of antimicrobial use, type of antibiotics used, and factors associated with their use. We rated antibiotic use as appropriate (when an effective drug was used), inappropriate (when a more effective drug was indicated), or unjustified (when use of any antimicrobial was not indicated). Results: Of 100 patients with RTI, overall treatment was appropriate in 79% of episodes, inappropriate in 9%, and unjustified in 12%. For acute bronchitis, treatment was appropriate in 85% and unjustified in 15% of cases. For pneumonia, treatment was appropriate in 55% of episodes. Among the most commonly used antimicrobials, B.Lactam + macrolides their use were unjustified in 41% of cases. There were statistical significant differences in the patterns of antibiotic use when stratified by age, gender, and co- morbid conditions including chronic obstructive pulmonary disease. Conclusion: Antimicrobials are unjustifiably used for 12% of RTIs and 15% of cases of acute bronchitis, thus suggesting a need for programs to improve antibiotic prescribing at hospitals.

Antimicrobial resistance challenged with metal-based antimicrobial macromolecules.

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Abd-El-Aziz, Alaa S; Agatemor, Christian; Etkin, Nola

2017-02-01

Antimicrobial resistance threatens the achievements of science and medicine, as it deactivates conventional antimicrobial therapeutics. Scientists respond to the threat by developing new antimicrobial platforms to prevent and treat infections from these resistant strains. Metal-based antimicrobial macromolecules are emerging as an alternative to conventional platforms because they combine multiple mechanisms of action into one platform due to the distinctive properties of metals. For example, metals interact with intracellular proteins and enzymes, and catalyse various intracellular processes. The macromolecular architecture offers a means to enhance antimicrobial activity since several antimicrobial moieties can be conjugated to the scaffold. Further, these macromolecules can be fabricated into antimicrobial materials for contact-killing medical implants, fabrics, and devices. As volatilization or leaching out of the antimicrobial moieties from the macromolecular scaffold is reduced, these medical implants, fabrics, and devices can retain their antimicrobial activity over an extended period. Recent advances demonstrate the potential of metal-based antimicrobial macromolecules as effective platforms that prevent and treat infections from resistant strains. In this review these advances are thoroughly discussed within the context of examples of metal-based antimicrobial macromolecules, their mechanisms of action and biocompatibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antimicrobial susceptibility of Clostridium difficile isolated in Thailand

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Papanin Putsathit

2017-06-01

Full Text Available Abstract Background Exposure to antimicrobials is the major risk factor associated with Clostridium difficile infection (CDI. Paradoxically, treatment of CDI with antimicrobials remains the preferred option. To date, only three studies have investigated the antimicrobial susceptibility of C. difficile from Thailand, two of which were published in the 1990s. This study aimed to investigate the contemporary antibiotic susceptibility of C. difficile isolated from patients in Thailand. Methods A collection of 105 C. difficile isolated from inpatients admitted at Siriraj Hospital in Bangkok in 2015 was tested for their susceptibility to nine antimicrobials via an agar incorporation method. Results All isolates were susceptible to vancomycin, metronidazole, amoxicillin/clavulanate and meropenem. Resistance to clindamycin, erythromycin and moxifloxacin was observed in 73.3%, 35.2% and 21.0% of the isolates, respectively. The in vitro activity of fidaxomicin (MIC50/MIC90 0.06/0.25 mg/L was superior to first-line therapies vancomycin (MIC50/MIC90 1/2 mg/L and metronidazole (MIC50/MIC90 0.25/0.25 mg/L. Rifaximin exhibited potent activity against 85.7% of the isolates (MIC ≤0.03 mg/L, and its MIC50 (0.015 mg/L was the lowest among all antimicrobials tested. The prevalence of multi-drug resistant C. difficile, defined by resistance to ≥3 antimicrobials, was 21.9% (23/105. Conclusions A high level of resistance against multiple classes of antimicrobial was observed, emphasising the need for enhanced antimicrobial stewardship and educational programmes to effectively disseminate information regarding C. difficile awareness and appropriate use of antimicrobials to healthcare workers and the general public.

Guanidylation and tail effects in cationic antimicrobial lipopeptoids.

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Brandon Findlay

Full Text Available Cationic antimicrobial peptides (CAMPs are attractive scaffolds for the next generation of antimicrobial compounds, due to their broad spectrum of activity against multi-drug resistant bacteria and the reduced fitness of CAMP-insensitive mutants. Unfortunately, they are limited by poor in vivo performance, including ready cleavage by endogenous serum proteases.To explore the potential for peptoid residues to replace well studied CAMP scaffolds we have produced a series of antimicrobial lipopeptoids, with sequences similar to previously reported lipopeptides. The activity of the peptoids was assessed against a panel of clinically relevant and laboratory reference bacteria, and the potential for non-specific binding was determined through hemolytic testing and repeating the antimicrobial testing in the presence of added bovine serum albumin (BSA. The most active peptoids displayed good to moderate activity against most of the gram positive strains tested and moderate to limited activity against the gram negatives. Antimicrobial activity was positively correlated with toxicity towards eukaryotic cells, but was almost completely eliminated by adding BSA.The lipopeptoids had similar activities to the previously reported lipopeptides, confirming their potential to act as replacement, proteolytically stable scaffolds for CAMPs.

Blue light irradiation triggers the antimicrobial potential of ZnO nanoparticles on drug-resistant Acinetobacter baumannii.

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Yang, Ming-Yeh; Chang, Kai-Chih; Chen, Liang-Yu; Wang, Po-Ching; Chou, Chih-Chiang; Wu, Zhong-Bin; Hu, Anren

2018-03-01

Photodynamic inactivation (PDI) is a non-invasive and safe therapeutic method for microbial infections. Bacterial antibiotic resistance is caused by antibiotics abuse. Drug-resistant Acinetobacter spp. is a serious problem in hospitals around the world. These pathogens from nosocomial infections have high mortality rates in frailer people, and Acinetobacter spp. is commonly found in immunocompromised patients. Visible light is safer than ultraviolet light (UV) for PDI of nosocomial pathogens with mammalian cells. Zinc oxide nanoparticles (ZnO-NPs) were used in this study as an antimicrobial agent and a photosensitizer. ZnO is recognized as safe and has extensive usage in food additives, medical and cosmetic products. In this study, we used 0.125 mg/ml ZnO-NPs combined with 10.8 J/cm 2 blue light (BL) on Acinetobacter baumannii (A. baumannii) that could significantly reduce microbial survival. However, individual exposure to ZnO-NPs does not affect the viability of A. baumannii. BL irradiation could trigger the antimicrobial ability of ZnO nanoparticles on A. baumannii. The mechanism of photocatalytic ZnO-NPs treatment for sterilization occurs through bacterial membrane disruptions. Otherwise, the photocatalytic ZnO-NPs treatment showed high microbial eradication in nosocomial pathogens, including colistin-resistant and imipenem-resistant A. baumannii and Klebsiella pneumoniae. Based on our results, the photocatalytic ZnO-NPs treatment could support hygiene control and clinical therapies without antibiotics to nosocomial bacterial infections. Copyright © 2018. Published by Elsevier B.V.

Phytochemical and antimicrobial study of an antidiabetic plant: Scoparia dulcis L.

Science.gov (United States)

Latha, M; Ramkumar, K M; Pari, L; Damodaran, P N; Rajeshkannan, V; Suresh, T

2006-01-01

The antimicrobial and antifungal effects of different concentrations of chloroform/methanol fractions of Scoparia dulcis were investigated. The isolated fractions were tested against different bacteria like Salmonella typhii, Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Proteus vulgaris and fungal strains such as Alternaria macrospora, Candida albicans, Aspergillus niger, and Fusarium oxysporum. The isolated fractions exhibited significant antimicrobial and antifungal activity against all the tested organisms compared with respective reference drugs. The isolated fractions of S. dulcis showed properties like antimicrobial and antifungal activities that will enable researchers in turn to look for application-oriented principles.

Evaluation of antimicrobial consumption in Campania Region, Italy

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Simona Cammarota

2008-01-01

Full Text Available Introduction: the antibiotic usage in Italy is above the European average. From several years the Campania was the first Italian region in terms of antimicrobial consumption. Aim: to evaluate antibiotic utilisation in primary health care in Campania, a region of approximately 5.7 million inhabitants in the south of Italy. Method: we collected, from an electronic database, all prescription drugs reimbursed in 2005. The cohort was defined as the population of subjects receiving at least one prescription of any antimicrobial agent for systemic use, classified according to their therapeutic role using Anatomic Therapeutic Chemical (ATC classification. Drugs cost and consumption were quantified using National Health Service (NHS prospective and Defined Daily Dose system (DDD respectively. All costs were expressed in Euro 2005. Results: antiinfectives agents (ATC J was the second class of drugs in terms of cost, representing 16.1% of the regional drug expenditure. Their consumption were 33 DDD/1000 inhabitants/day. Stratifying by age antibiotic use was highest in children and elderly subjects. Penicillins, macrolides and cephalosporins were the most prescribed antibiotic classes in all age groups. Discussion: despite guidelines introduced to limit the prescription of parenteral antibiotics to the patients who are most likely to benefit from it, they were mostly prescribed. This represented a serious problem for the development of drug-resistant bacteria.

Antibiotic Conjugated Fluorescent Carbon Dots as a Theranostic Agent for Controlled Drug Release, Bioimaging, and Enhanced Antimicrobial Activity

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Mukeshchand Thakur

2014-01-01

Full Text Available A novel report on microwave assisted synthesis of bright carbon dots (C-dots using gum arabic (GA and its use as molecular vehicle to ferry ciprofloxacin hydrochloride, a broad spectrum antibiotic, is reported in the present work. Density gradient centrifugation (DGC was used to separate different types of C-dots. After careful analysis of the fractions obtained after centrifugation, ciprofloxacin was attached to synthesize ciprofloxacin conjugated with C-dots (Cipro@C-dots conjugate. Release of ciprofloxacin was found to be extremely regulated under physiological conditions. Cipro@C-dots were found to be biocompatible on Vero cells as compared to free ciprofloxacin (1.2 mM even at very high concentrations. Bare C-dots (∼13 mg mL−1 were used for microbial imaging of the simplest eukaryotic model—Saccharomyces cerevisiae (yeast. Bright green fluorescent was obtained when live imaging was performed to view yeast cells under fluorescent microscope suggesting C-dots incorporation inside the cells. Cipro@C-dots conjugate also showed enhanced antimicrobial activity against both model gram positive and gram negative microorganisms. Thus, the Cipro@C-dots conjugate paves not only a way for bioimaging but also an efficient new nanocarrier for controlled drug release with high antimicrobial activity, thereby serving potential tool for theranostics.

Drug induced aseptic meningitis

African Journals Online (AJOL)

PROF. EZECHUKWU

2013-09-29

Sep 29, 2013 ... Abstract. Drug-induced aseptic meningitis (DIAM) is a rare but important and often challenging diagnosis for the physician. Intake of antimicrobials, steroids, anal- gesics amongst others has been implicated. Signs and symptoms generally develop within 24-48 hours of drug ingestion. The pa- tient often ...

Protein-only, antimicrobial peptide-containing recombinant nanoparticles with inherent built-in antibacterial activity.

Science.gov (United States)

Serna, Naroa; Sánchez-García, Laura; Sánchez-Chardi, Alejandro; Unzueta, Ugutz; Roldán, Mónica; Mangues, Ramón; Vázquez, Esther; Villaverde, Antonio

2017-09-15

The emergence of bacterial antibiotic resistances is a serious concern in human and animal health. In this context, naturally occurring cationic antimicrobial peptides (AMPs) might play a main role in a next generation of drugs against bacterial infections. Taking an innovative approach to design self-organizing functional proteins, we have generated here protein-only nanoparticles with intrinsic AMP microbicide activity. Using a recombinant version of the GWH1 antimicrobial peptide as building block, these materials show a wide antibacterial activity spectrum in absence of detectable toxicity on mammalian cells. The GWH1-based nanoparticles combine clinically appealing properties of nanoscale materials with full biocompatibility, structural and functional plasticity and biological efficacy exhibited by proteins. Because of the largely implemented biological fabrication of recombinant protein drugs, the protein-based platform presented here represents a novel and scalable strategy in antimicrobial drug design, that by solving some of the limitations of AMPs offers a promising alternative to conventional antibiotics. The low molecular weight antimicrobial peptide GWH1 has been engineered to oligomerize as self-assembling protein-only nanoparticles of around 50nm. In this form, the peptide exhibits potent and broad antibacterial activities against both Gram-positive and Gram-negative bacteria, without any harmful effect over mammalian cells. As a solid proof-of-concept, this finding strongly supports the design and biofabrication of nanoscale antimicrobial materials with in-built functionalities. The protein-based homogeneous composition offer advantages over alternative materials explored as antimicrobial agents, regarding biocompatibility, biodegradability and environmental suitability. Beyond the described prototype, this transversal engineering concept has wide applicability in the design of novel nanomedicines for advanced treatments of bacterial infections

Activities and influence of veterinary drug marketers on antimicrobial usage in livestock production in Oyo and Kaduna States, Nigeria

OpenAIRE

Olufemi Ernest Ojo; Olajoju Jokotola Awoyomi; Eniola Fabusoro; Morenike Atinuke Dipeolu

2017-01-01

Antimicrobial usage in animals contributes to the emergence of antimicrobial resistant bacterial strains. Investigations were carried out on how the characteristics, knowledge, attitude and practices of antimicrobial marketers influenced antimicrobials usage in animal production in Oyo and Kaduna States, Nigeria. Focus group discussions, in-depth interviews and structured questionnaires were used to gather information about the characteristics and activities of antimicrobial marketers. Overal...

Declines in Outpatient Antimicrobial Use in Canada (1995–2010)

Science.gov (United States)

Finley, Rita; Glass-Kaastra, Shiona K.; Hutchinson, Jim; Patrick, David M.; Weiss, Karl; Conly, John

2013-01-01

Background With rising reports of antimicrobial resistance in outpatient communities, surveillance of antimicrobial use is imperative for supporting stewardship programs. The primary objective of this article is to assess the levels of antimicrobial use in Canada over time. Methods Canadian antimicrobial use data from 1995 to 2010 were acquired and assessed by four metrics: population-adjusted prescriptions, Defined Daily Doses, spending on antimicrobials (inflation-adjusted), and average Defined Daily Doses per prescription. Linear mixed models were built to assess significant differences among years and antimicrobial groups, and to account for repeated measurements over time. Measures were also compared to published reports from European countries. Results Temporal trends in antimicrobial use in Canada vary by metric and antimicrobial grouping. Overall reductions were seen for inflation-adjusted spending, population-adjusted prescription rates and Defined Daily Doses, and increases were observed for the average number of Defined Daily Doses per prescription. The population-adjusted prescription and Defined Daily Doses values for 2009 were comparable to those reported by many European countries, while the average Defined Daily Dose per prescription for Canada ranked high. A significant reduction in the use of broad spectrum penicillins occurred between 1995 and 2004, coupled with increases in macrolide and quinolone use, suggesting that replacement of antimicrobial drugs may occur as new products arrive on the market. Conclusions There have been modest decreases of antimicrobial use in Canada over the past 15 years. However, continued surveillance of antimicrobial use coupled with data detailing antimicrobial resistance within bacterial pathogens affecting human populations is critical for targeting interventions and maintaining the effectiveness of these products for future generations. PMID:24146863

Non-observance of guidelines for surgical antimicrobial prophylaxis and surgical-site infections.

Science.gov (United States)

Lallemand, S; Thouverez, M; Bailly, P; Bertrand, X; Talon, D

2002-06-01

A prospective multicentre study was conducted to assess major aspects of surgical prophylaxis and to determine whether inappropriate antimicrobial prophylaxis was a factor associated (risk or protective factor) with surgical site infection (SSI). Surgical prophylaxis practices were assessed by analysing four variables: indication, antimicrobial agent, timing and duration. Univariate and multivariate analyses were carried out to identify predictors of SSI among patient-specific, operation-specific and antimicrobial prophylaxis-specific factors. The frequency of SSI was 2.7% (13 SSI in 474 observations). Total compliance of the prescription with guidelines was observed in 41.1% of cases (195 prescriptions). Of the 139 patients who received an inappropriate drug, 126 (90.6%) received a drug with a broader spectrum than the recommended drug. Prophylaxis was prolonged in 71 (87.7%) of the 81 patients who received prophylaxis for inappropriate lengths of time and 43 (61.4%) of the 70 patients who did not receive prophylaxis at the optimal moment were treated too late. Multivariate analysis clearly demonstrated that SSI was associated with multiple procedures (relative risk 8.5), short duration of prophylaxis (relative risk 12.7) and long-term therapy with antimicrobial agents during the previous year (relative risk 8.8). The ecological risk of the emergence of resistance associated with the frequent use of broad-spectrum antibiotics and prophylaxis for longer periods was not offset by individual benefit to the patients who received inappropriate prophylaxis.

Factors associated with the inappropriate use of antimicrobials.

Science.gov (United States)

McIntosh, W; Dean, W

2015-04-01

Antimicrobial resistance continues to grow and antimicrobial use in food animal production and to a lesser extent in human patients is under fire. Much of the criticism has to do with the misapplication of these drugs in both settings. Research indicates that patients, food animal producers, physicians and veterinarians have all played a part in misusing antimicrobials, often because of mistaken beliefs. This paper reviews this research and introduces a theoretical perspective, the Theory of Planned Behavior (TPB), which broadens our understanding of the motivations for misuse. In particular this approach shows that individuals making decisions about antimicrobial use take into account social pressures from and a sense of obligation to significant others in their social networks. Our own work summarized in this paper indicates that both feedlot veterinarians and feedlot managers' antimicrobial decisions are influenced by both expectations from and obligations to a variety of actors in the feedlot network (other veterinarians, feedlot clients, consumers, pharmaceutical companies, and regulatory bodies). Generally across 4 circumstances of antimicrobial use (for acutely sick cattle, chronically-sick cattle, at-risk cattle, high-risk cattle), it is largely the perception that peers and clients expect feedlot veterinarians to use antimicrobials and feedlot veterinarians sense of obligation to these groups that have the most influence on their decisions to recommend antimicrobials. Based on these findings, the question of engaging in changing the choices made by those working with food animals must start with those who influence the decision to proscribe or use antimicrobials. As our data come from the United States and may be unique relative to other countries, these efforts should begin by ascertaining who influences these decisions. The next step is to then change the beliefs of these significant others. © 2014 Blackwell Verlag GmbH.

Global Governance Mechanisms to Address Antimicrobial Resistance.

Science.gov (United States)

Padiyara, Ponnu; Inoue, Hajime; Sprenger, Marc

2018-01-01

Since their discovery, antibiotics, and more broadly, antimicrobials, have been a cornerstone of modern medicine. But the overuse and misuse of these drugs have led to rising rates of antimicrobial resistance, which occurs when bacteria adapt in ways that render antibiotics ineffective. A world without effective antibiotics can have drastic impacts on population health, global development, and the global economy. As a global common good, antibiotic effectiveness is vulnerable to the tragedy of the commons, where a shared limited resource is overused by a community when each individual exploits the finite resource for their own benefit. A borderless threat like antimicrobial resistance requires global governance mechanisms to mitigate its emergence and spread, and it is the responsibility of all countries and relevant multilateral organizations. These mechanisms can be in the form of legally binding global governance mechanisms such as treaties and regulatory standards or nonbinding mechanisms such as political declarations, resolutions, or guidelines. In this article, we argue that while both are effective methods, the strong, swift, and coordinated action needed to address rising rates of antimicrobial resistance will be better served through legally binding governance mechanisms.

Repurposing Clinical Molecule Ebselen to Combat Drug Resistant Pathogens.

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Thangamani, Shankar; Younis, Waleed; Seleem, Mohamed N

2015-01-01

Without a doubt, our current antimicrobials are losing the battle in the fight against newly-emerged multidrug-resistant pathogens. There is a pressing, unmet need for novel antimicrobials and novel approaches to develop them; however, it is becoming increasingly difficult and costly to develop new antimicrobials. One strategy to reduce the time and cost associated with antimicrobial innovation is drug repurposing, which is to find new applications outside the scope of the original medical indication of the drug. Ebselen, an organoselenium clinical molecule, possesses potent antimicrobial activity against clinical multidrug-resistant Gram-positive pathogens, including Staphylococcus, Streptococcus, and Enterococcus, but not against Gram-negative pathogens. Moreover, the activity of ebselen against Gram-positive pathogens exceeded those activities determined for vancomycin and linezolid, drugs of choice for treatment of Enterococcus and Staphylococcus infections. The minimum inhibitory concentrations of ebselen at which 90% of clinical isolates of Enterococcus and Staphylococcus were inhibited (MIC90) were found to be 0.5 and 0.25 mg/L, respectively. Ebselen showed significant clearance of intracellular methicillin-resistant S. aureus (MRSA) in comparison to vancomycin and linezolid. We demonstrated that ebselen inhibits the bacterial translation process without affecting mitochondrial biogenesis. Additionally, ebselen was found to exhibit excellent activity in vivo in a Caenorhabditis elegans MRSA-infected whole animal model. Finally, ebselen showed synergistic activities with conventional antimicrobials against MRSA. Taken together, our results demonstrate that ebselen, with its potent antimicrobial activity and safety profiles, can be potentially used to treat multidrug resistant Gram-positive bacterial infections alone or in combination with other antibiotics and should be further clinically evaluated.

Expanded therapeutic potential in activity space of next-generation 5-nitroimidazole antimicrobials with broad structural diversity

Science.gov (United States)

Miyamoto, Yukiko; Kalisiak, Jarosław; Korthals, Keith; Lauwaet, Tineke; Cheung, Dae Young; Lozano, Ricardo; Cobo, Eduardo R.; Upcroft, Peter; Upcroft, Jacqueline A.; Berg, Douglas E.; Gillin, Frances D.; Fokin, Valery V.; Sharpless, K. Barry; Eckmann, Lars

2013-01-01

Metronidazole and other 5-nitroimidazoles (5-NI) are among the most effective antimicrobials available against many important anaerobic pathogens, but evolving resistance is threatening their long-term clinical utility. The common 5-NIs were developed decades ago, yet little 5-NI drug development has since taken place, leaving the true potential of this important drug class unexplored. Here we report on a unique approach to the modular synthesis of diversified 5-NIs for broad exploration of their antimicrobial potential. Many of the more than 650 synthesized compounds, carrying structurally diverse functional groups, have vastly improved activity against a range of microbes, including the pathogenic protozoa Giardia lamblia and Trichomonas vaginalis, and the bacterial pathogens Helicobacter pylori, Clostridium difficile, and Bacteroides fragilis. Furthermore, they can overcome different forms of drug resistance, and are active and nontoxic in animal infection models. These findings provide impetus to the development of structurally diverse, next-generation 5-NI drugs as agents in the antimicrobial armamentarium, thus ensuring their future viability as primary therapeutic agents against many clinically important infections. PMID:24101497

World Health Organization Ranking of Antimicrobials According to Their Importance in Human Medicine: A Critical Step for Developing Risk Management Strategies to Control Antimicrobial Resistance From Food Animal Production.

Science.gov (United States)

Collignon, Peter C; Conly, John M; Andremont, Antoine; McEwen, Scott A; Aidara-Kane, Awa; Agerso, Yvonne; Andremont, Antoine; Collignon, Peter; Conly, John; Dang Ninh, Tran; Donado-Godoy, Pilar; Fedorka-Cray, Paula; Fernandez, Heriberto; Galas, Marcelo; Irwin, Rebecca; Karp, Beth; Matar, Gassan; McDermott, Patrick; McEwen, Scott; Mitema, Eric; Reid-Smith, Richard; Scott, H Morgan; Singh, Ruby; DeWaal, Caroline Smith; Stelling, John; Toleman, Mark; Watanabe, Haruo; Woo, Gun-Jo

2016-10-15

Antimicrobial use in food animals selects for antimicrobial resistance in bacteria, which can spread to people. Reducing use of antimicrobials-particularly those deemed to be critically important for human medicine-in food production animals continues to be an important step for preserving the benefits of these antimicrobials for people. The World Health Organization ranking of antimicrobials according to their relative importance in human medicine was recently updated. Antimicrobials considered the highest priority among the critically important antimicrobials were quinolones, third- and fourth-generation cephalosporins, macrolides and ketolides, and glycopeptides. The updated ranking allows stakeholders in the agriculture sector and regulatory agencies to focus risk management efforts on drugs used in food animals that are the most important to human medicine. In particular, the current large-scale use of fluoroquinolones, macrolides, and third-generation cephalosporins and any potential use of glycopeptides and carbapenems need to be addressed urgently. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

In Vitro Antimicrobial Potential of the Lichen Parmotrema sp. Extracts against Various Pathogens.

Science.gov (United States)

Chauhan, Ritika; Abraham, Jayanthi

2013-07-01

The ongoing increasing antibiotic resistance is one of the biggest challenges faced by global public health. The perennial need for new antimicrobials against a background of increasing antibiotic resistance in pathogenic and opportunistic microorganisms obliges the scientific community to constantly develop new drugs and antimicrobial agents. Lichens are known prolific sources of natural antimicrobial drugs and biologically active natural products. This study was aimed to explore in vitro antimicrobial activity of lichen Parmotrema sp. The methanol and aqueous extracts of lichen Parmotrema sp. was extracted using Soxhlet extractor. Antibiotic assessment of methanol and aqueous extracts was done against eight bacterial (Escherichia coli, Staphylococcus aureus, Proteus mirabilis, Salmonella sp., Shigella sp., Enterococci faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae,) clinical pathogens and five plant pathogenic fungal strains (Aspergillus terreus strain JAS1, Scedosporium sp. JAS1, Ganoderma sp. JAS4, Candida tropicalis and Fusarium sp.) by Kirby-Bauer method. The methanol lichen Parmotrema sp. extract inhibited all the test organisms. The highest antibacterial activity was found against Pseudomonas aeruginosa and Staphylococcus aureus. The weakest activity was manifested in Salmonella sp. and Scedosporium sp. JAS1. Strong antifungal effect was found against Ganoderma sp. JAS4 and Fusarium sp. The aqueous lichen Parmotrema sp. extract revealed neither antibacterial nor antifungal activity. The present study shows that tested lichen Parmotrema sp. extracts demonstrated a strong antimicrobial effect. That suggests the active components from methanol extracts of the investigated lichen Parmotrema sp. can be used as natural antimicrobial agent against pathogens.

Guidelines for the diagnosis and antimicrobial therapy of canine superficial bacterial folliculitis (Antimicrobial Guidelines Working Group of the International Society for Companion Animal Infectious Diseases)

DEFF Research Database (Denmark)

Hillier, Andrew; Lloyd, David H.; Weese, J. Scott

2014-01-01

from diplomates of the American and European Colleges of Veterinary Dermatology. They describe optimal methods for the diagnosis and management of SBF, including isolation of the causative organism, antimicrobial susceptibility testing, selection of antimicrobial drugs, therapeutic protocols and advice......BACKGROUND: Superficial bacterial folliculitis (SBF) is usually caused by Staphylococcus pseudintermedius and routinely treated with systemic antimicrobial agents. Infection is a consequence of reduced immunity associated with alterations of the skin barrier and underlying diseases that may...... be difficult to diagnose and resolve; thus, SBF is frequently recurrent and repeated treatment is necessary. The emergence of multiresistant bacteria, particularly meticillin-resistant S. pseudintermedius (MRSP), has focused attention on the need for optimal management of SBF. OBJECTIVES: Provision...

Self-assembling systems based on quaternized derivatives of 1,4-diazabicyclo[2.2.2]octane in nutrient broth as antimicrobial agents and carriers for hydrophobic drugs.

Science.gov (United States)

Pashirova, Tatiana N; Lukashenko, Svetlana S; Zakharov, Sergey V; Voloshina, Alexandra D; Zhiltsova, Elena P; Zobov, Vladimir V; Souto, Eliana B; Zakharova, Lucia Ya

2015-03-01

Aggregation properties of mono (mono-CS) and dicationic (di-CS) surfactants, namely quaternised derivatives of 1,4-diazabicyclo[2.2.2]octane (DABCO), have been evaluated in water and in nutrient broths of different pH, i.e. in Hottinger broth (рН=7.2) and Sabouraud dextrose broth (рН=5.6). Aggregation capacity of surfactants was shown to be responsible for the solubilization properties of a complex composed of a hydrophobic probe (Sudan I) and a selected drug (quercetin), contributing to the antimicrobial activity of this surfactant system. The effect of N-methyl-d-glucamine (NmDg) additive on the antimicrobial activity of mono-CS, and its aggregation and solubilization parameters, has also been evaluated. A substantial decrease in critical micelle concentration (CMC) of cationic surfactants in nutrient broths (up to 60 times) has been reported. Twofold dilution of monocationic surfactant by NmDg slightly changed the CMC of surfactant; however, it provided a remarkable increase in solubilization capacity (∼by 4 times) and decrease in its toxicity. The data anticipate the potential use of DABCO quaternized derivatives as innovative non-toxic delivery systems for hydrophobic drugs. Copyright © 2015 Elsevier B.V. All rights reserved.

Chitosan based metallic nanocomposite scaffolds as antimicrobial wound dressings.

Science.gov (United States)

Mohandas, Annapoorna; Deepthi, S; Biswas, Raja; Jayakumar, R

2018-09-01

Chitosan based nanocomposite scaffolds have attracted wider applications in medicine, in the area of drug delivery, tissue engineering and wound healing. Chitosan matrix incorporated with nanometallic components has immense potential in the area of wound dressings due to its antimicrobial properties. This review focuses on the different combinations of Chitosan metal nanocomposites such as Chitosan/nAg, Chitosan/nAu, Chitosan/nCu, Chitosan/nZnO and Chitosan/nTiO 2 towards enhancement of healing or infection control with special reference to the antimicrobial mechanism of action and toxicity.

Will new antimicrobials overcome resistance among Gram-negatives?

Science.gov (United States)

Bassetti, Matteo; Ginocchio, Francesca; Mikulska, Małgorzata; Taramasso, Lucia; Giacobbe, Daniele Roberto

2011-10-01

The spread of resistance among Gram-positive and Gram-negative bacteria represents a growing challenge for the development of new antimicrobials. The pace of antibiotic drug development has slowed during the last decade and, especially for Gram-negatives, clinicians are facing a dramatic shortage in the availability of therapeutic options to face the emergency of the resistance problem throughout the world. In this alarming scenario, although there is a shortage of compounds reaching the market in the near future, antibiotic discovery remains one of the keys to successfully stem and maybe overcome the tide of resistance. Analogs of already known compounds and new agents belonging to completely new classes of antimicrobials are in early stages of development. Novel and promising anti-Gram-negative antimicrobials belong both to old (cephalosporins, carbapenems, β-lactamase inhibitors, monobactams, aminoglycosides, polymyxin analogues and tetracycline) and completely new antibacterial classes (boron-containing antibacterial protein synthesis inhibitors, bis-indoles, outer membrane synthesis inhibitors, antibiotics targeting novel sites of the 50S ribosomal subunit and antimicrobial peptides). However, all of these compounds are still far from being introduced into clinical practice. Therefore, infection control policies and optimization in the use of already existing molecules are still the most effective approaches to reduce the spread of resistance and preserve the activity of antimicrobials.

Evaluation of new antimicrobials for the hospital formulary. Policies restricting antibiotic use in hospitals.

Science.gov (United States)

Pujol, Miquel; Delgado, Olga; Puigventós, Francesc; Corzo, Juan E; Cercenado, Emilia; Martínez, José Antonio

2013-09-01

In Spain, the inclusion of new antibiotics in hospital formularies is performed by the Infection Policy Committee or the Pharmacy and Therapeutic Committee, although now the decision is moving to a regional level. Criteria for the evaluation of new drugs include efficacy, safety and cost. For antimicrobial drugs evaluation it is necessary to consider local sensibility and impact in bacterial resistance to determinate the therapeutic positioning. There is compelling evidence that the use of antibiotics is associated with increasing bacterial resistance, and a great number of antibiotics are used incorrectly. In order to decrease the inappropriate use of antibiotics, several approaches have been proposed. Limiting the use of antimicrobials through formulary restrictions, often aimed at drugs with a specific resistance profile, shows benefits in improving antimicrobial susceptibilities and decreasing colonization by drug-resistant organisms. However, the restriction of one agent may result in the increased utilization of other agents. By using antibiotic cycling, the amount of antibiotics is maintained below the threshold where bacterial resistance develops, thus preserving highly efficient antibiotics. Unfortunately, cumulative evidence to date suggests that antibiotic cycling has limited efficacy in preventing antibiotic resistance. Finally, although there is still little clinical evidence available on antibiotic heterogeneity, the use of most of the existing antimicrobial classes could limit the emergence of resistance. This review summarizes information regarding antibiotic evaluation and available restrictive strategies to limit the use of antibiotics at hospitals with the aim of curtailing increasing antibiotic resistance. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Antimicrobial susceptibility of Staphylococcus aureus isolated from bovine mastitis in Europe and the United States

DEFF Research Database (Denmark)

De Oliveira, A. P.; Watts, J. L.; Salmon, S. A.

2000-01-01

Minimum inhibitory concentrations were determined for 811 strains of Staphylococcus aureus isolated from cases of bovine mastitis in 11 countries. The countries and number of isolates included Denmark (105), England (92), Finland (95), Germany (103), Iceland (22), Ireland (42), Norway (101), Sweden...... antimicrobial agents tested regardless of country. Given the differences in antimicrobial use in various countries, the widespread adoption of mastitis control programs to prevent infections limits the exposure of S. aureus infected animals to antimicrobial drugs....

Multistrain models predict sequential multidrug treatment strategies to result in less antimicrobial resistance than combination treatment

DEFF Research Database (Denmark)

Ahmad, Amais; Zachariasen, Camilla; Christiansen, Lasse Engbo

2016-01-01

Background: Combination treatment is increasingly used to fight infections caused by bacteria resistant to two or more antimicrobials. While multiple studies have evaluated treatment strategies to minimize the emergence of resistant strains for single antimicrobial treatment, fewer studies have...... the sensitive fraction of the commensal flora.Growth parameters for competing bacterial strains were estimated from the combined in vitro pharmacodynamic effect of two antimicrobials using the relationship between concentration and net bacterial growth rate. Predictions of in vivo bacterial growth were...... (how frequently antibiotics are alternated in a sequential treatment) of the two drugs was dependent upon the order in which the two drugs were used.Conclusion: Sequential treatment was more effective in preventing the growth of resistant strains when compared to the combination treatment. The cycling...

78 FR 26935 - Data Requirements for Antimicrobial Pesticides

Science.gov (United States)

2013-05-08

... pesticides used in conjunction with the manufacturing and processing of foods, at that time, were regulated....S.C. 136 et seq., and section 408 of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C.... Antimicrobial pesticides are used to control microbiological contamination in healthcare applications, and...

Chemical constituents, in vitro antimicrobial and cytotoxic potentials of the extracts from Macaranga barteri Mull-Arg

Directory of Open Access Journals (Sweden)

Akintayo Ogundajo

2017-07-01

Conclusions: Methanol fraction of M. barteri is a potent and safe antimicrobial and antifungal alternative which can be useful in the search for new antimicrobial drugs. The study also confirmed the orthodox usage of M. barteri in combating infectious diseases.

Analytical method development and validation of spectrofluorimetric and spectrophotometric determination of some antimicrobial drugs in their pharmaceuticals

Science.gov (United States)

Ibrahim, F.; Wahba, M. E. K.; Magdy, G.

2018-01-01

In this study, three novel, sensitive, simple and validated spectrophotometric and spectrofluorimetric methods have been proposed for estimation of some important antimicrobial drugs. The first two methods have been proposed for estimation of two important third-generation cephalosporin antibiotics namely, cefixime and cefdinir. Both methods were based on condensation of the primary amino group of the studied drugs with acetyl acetone and formaldehyde in acidic medium. The resulting products were measured by spectrophotometric (Method I) and spectrofluorimetric (Method II) tools. Regarding method I, the absorbance was measured at 315 nm and 403 nm with linearity ranges of 5.0-140.0 and 10.0-100.0 μg/mL for cefixime and cefdinir, respectively. Meanwhile in method II, the produced fluorophore was measured at λem 488 nm or 491 nm after excitation at λex 410 nm with linearity ranges of 0.20-10.0 and 0.20-36.0 μg/mL for cefixime and cefdinir, respectively. On the other hand, method III was devoted to estimate nifuroxazide spectrofluorimetrically depending on formation of highly fluorescent product upon reduction of the studied drug with Zinc powder in acidic medium. Measurement of the fluorescent product was carried out at λem 335 nm following excitation at λex 255 nm with linearity range of 0.05 to 1.6 μg/mL. The developed methods were subjected to detailed validation procedure, moreover they were used for the estimation of the concerned drugs in their pharmaceuticals. It was found that there is a good agreement between the obtained results and those obtained by the reported methods.

Antimicrobial and Herbal Drug Resistance in Enteric Bacteria Isolated from Faecal Droppings of Common House Lizard/Gecko (Hemidactylus frenatus

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Bhoj R. Singh

2013-01-01

Full Text Available From 194 faecal dropping samples of common house geckos collected from offices (60, houses (88, integrated farm units (IFS,18 and hostels, guest houses, and dining rooms of different canteen/mess (HGM, 28, 326 bacterial isolates of enteric bacteria belonging to 17 genera and 34 species were detected. Escherichia coli were the most frequently (39 isolated followed by Citrobacter freundii (33, Klebsiella pneumonia (27, Salmonella indica (12, Enterobacter gergoviae (12, and Ent. agglomerans (11. Other important bacteria isolated from gecko droppings were Listonella damsela (2, Raoultella terrigena (3, S. salamae (2, S. houtenae (3, Edwardsiella tarda (4, Edwardsiella hoshinae (1, and Klebsiella oxytoca (2. Of the 223 isolates tested for antimicrobial drug sensitivity, 27 (12.1% had multiple drug resistance (MDR. None of the salmonellae or edwardsiellae had MDR however, MDR strains were significantly more common among Escherichia spp. (P=1.9×10-5 and isolates from IFS units (P=3.58×10-23. The most effective herbal drug, Ageratum conyzoides extract, inhibited growth of only 27.8% of strains tested followed by ethanolic extract of Zanthoxylum rhetsa (13.9%, eucalyptus oil (5.4%, patchouli oil (5.4%, lemongrass oil (3.6%, and sandalwood oil (3.1%, and Artemisia vulgaris essential oil (3.1%.

Repurposing Clinical Molecule Ebselen to Combat Drug Resistant Pathogens.

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Shankar Thangamani

Full Text Available Without a doubt, our current antimicrobials are losing the battle in the fight against newly-emerged multidrug-resistant pathogens. There is a pressing, unmet need for novel antimicrobials and novel approaches to develop them; however, it is becoming increasingly difficult and costly to develop new antimicrobials. One strategy to reduce the time and cost associated with antimicrobial innovation is drug repurposing, which is to find new applications outside the scope of the original medical indication of the drug. Ebselen, an organoselenium clinical molecule, possesses potent antimicrobial activity against clinical multidrug-resistant Gram-positive pathogens, including Staphylococcus, Streptococcus, and Enterococcus, but not against Gram-negative pathogens. Moreover, the activity of ebselen against Gram-positive pathogens exceeded those activities determined for vancomycin and linezolid, drugs of choice for treatment of Enterococcus and Staphylococcus infections. The minimum inhibitory concentrations of ebselen at which 90% of clinical isolates of Enterococcus and Staphylococcus were inhibited (MIC90 were found to be 0.5 and 0.25 mg/L, respectively. Ebselen showed significant clearance of intracellular methicillin-resistant S. aureus (MRSA in comparison to vancomycin and linezolid. We demonstrated that ebselen inhibits the bacterial translation process without affecting mitochondrial biogenesis. Additionally, ebselen was found to exhibit excellent activity in vivo in a Caenorhabditis elegans MRSA-infected whole animal model. Finally, ebselen showed synergistic activities with conventional antimicrobials against MRSA. Taken together, our results demonstrate that ebselen, with its potent antimicrobial activity and safety profiles, can be potentially used to treat multidrug resistant Gram-positive bacterial infections alone or in combination with other antibiotics and should be further clinically evaluated.

ANTIMICROBIAL ACTIVITY OF GYMNOSPERMA GLUTINOSUM (SPRENG.) LESS. (ASTERACEAE) METHANOL EXTRACTS AGAINST HELICOBACTER PYLORI

OpenAIRE

Gomez-Flores, Ricardo; Espinosa-Ramos, David; Quintanilla-Licea, Ramiro; Barr?n-Gonzalez, Mar?a Porfiria; Tamez-Guerra, Patricia; Tamez-Guerra, Reyes; Rodriguez-Padilla, Cristina

2016-01-01

Background: Prolonged use of antibiotics may lead to the selection of drug-resistant bacteria; as a result, efforts are being made to identify new and effective antimicrobial agents, particularly, from medicinal plants, against bacterial infections. Antimicrobial activity of Gymnosperma glutinosum against Helicobacter pylori has not yet been reported. Materials and methods: The antibacterial in vitro effect of Gymnosperma glutinosum methanol leaf extracts against Helicobacter pylori (ATCC 435...

Antimicrobials used for surgical prophylaxis by equine veterinary practitioners in Australia.

Science.gov (United States)

Hardefeldt, L Y; Browning, G F; Thursky, K; Gilkerson, J R; Billman-Jacobe, H; Stevenson, M A; Bailey, K E

2018-01-01

Antimicrobials are widely used in Australian veterinary practices, but no investigation into the classes of antimicrobials used, or the appropriateness of use in horses, has been conducted. The aim of the study was to describe antimicrobial use for surgical prophylaxis in equine practice in Australia. Cross-sectional questionnaire survey. An online questionnaire was used to document antimicrobial usage patterns. Information solicited in the questionnaire included demographic details of the respondents, the frequency with which antimicrobials were used for specific surgical conditions (including the dose, timing and duration of therapy) and practice antimicrobial use policies and sources of information about antimicrobials and their uses. A total of 337 members of the Australian veterinary profession completed the survey. Generally, the choice of antimicrobial was appropriate for the specified equine surgical condition, but the dose and duration of therapy varied greatly. While there was poor optimal compliance with British Equine Veterinary Association guidelines in all scenarios (range 1-15%), except removal of a nonulcerated dermal mass (42%), suboptimal compliance (compliant antimicrobial drug selection but inappropriate timing, dose or duration of therapy) was moderate for all scenarios (range 48-68%), except for an uninfected contaminated wound over the thorax, where both optimal and suboptimal compliance was very poor (1%). Veterinarians practicing at a university hospital had higher odds of compliance than general practice veterinarians (Odds ratio 3.2, 95% CI, 1.1-8.9, P = 0.03). Many survey responses were collected at conferences which may introduce selection bias, as veterinarians attending conferences may be more likely to have been exposed to contemporary antimicrobial prescribing recommendations. Antimicrobial use guidelines need to be developed and promoted to improve the responsible use of antimicrobials in equine practice in Australia. An emphasis

Deep Subseafloor Fungi as an Untapped Reservoir of Amphipathic Antimicrobial Compounds.

Science.gov (United States)

Navarri, Marion; Jégou, Camille; Meslet-Cladière, Laurence; Brillet, Benjamin; Barbier, Georges; Burgaud, Gaëtan; Fleury, Yannick

2016-03-10

The evolving global threat of antimicrobial resistance requires a deep renewal of the antibiotic arsenal including the isolation and characterization of new drugs. Underexplored marine ecosystems may represent an untapped reservoir of novel bioactive molecules. Deep-sea fungi isolated from a record-depth sediment core of almost 2000 m below the seafloor were investigated for antimicrobial activities. This antimicrobial screening, using 16 microbial targets, revealed 33% of filamentous fungi synthesizing bioactive compounds with activities against pathogenic bacteria and fungi. Interestingly, occurrence of antimicrobial producing isolates was well correlated with the complexity of the habitat (in term of microbial richness), as higher antimicrobial activities were obtained at specific layers of the sediment core. It clearly highlights complex deep-sea habitats as chemical battlefields where synthesis of numerous bioactive compounds appears critical for microbial competition. The six most promising deep subseafloor fungal isolates were selected for the production and extraction of bioactive compounds. Depending on the fungal isolates, antimicrobial compounds were only biosynthesized in semi-liquid or solid-state conditions as no antimicrobial activities were ever detected using liquid fermentation. An exception was made for one fungal isolate, and the extraction procedure designed to extract amphipathic compounds was successful and highlighted the amphiphilic profile of the bioactive metabolites.

Antimicrobial sensitivity and frequency of DRUG resistance among bacterial strains isolated from cancer patients

International Nuclear Information System (INIS)

Faiz, M.; Bashir, T.

2004-01-01

Blood stream infections (bacteremia) is potentially life threatening. Concomitant with a change in the incidence and epidemiology of infecting organisms, there has been an increase in resistance to many antibiotic compounds. The widespread emergence of resistance among bacterial pathogens has an impact on our ability to treat patients effectively. The changing spectrum of microbial pathogens and widespread emergence of microbial resistance to antibiotic drugs has emphasized the need to monitor the prevalence of resistance in these strains. In the present study frequency of isolation of clinically significant bacteria and their susceptibility and resistance pattern against a wide range of antimicrobial drugs from positive blood cultures collected during 2001-2003 was studied. A total of 102 consecutive isolates were found with 63% gram positive and 44% gram negative strains. The dominating pathogens were Staphylococcus aureus (51%), Streptococci (31%), Pseudomonas (40%), Proteus (13%), Klebsiella (13%). The isolated strains were tested against a wide range of antibiotics belonging to cephalosporins, aminoglycosides and quinolone derivative group by disk diffusion method. It has been observed that isolated strains among gram positive and negative strains showed different level of resistance against aminoglycosides and cephalosporin group of antibiotics with gram positives showing highest number and frequency of resistance against aminoglycosides (40-50%) and cephalosporins.(35-45%) whereas cephalosporins were found to be more effective against gram negatives with low frequency of resistant strains. Cabapenem and quinolone derivative drugs were found to be most effective among other groups in both gram positive and negative strains with 23-41% strains found sensitive to these two drugs. The frequency of sensitive strains against aminoglycoside and cephalosporin in gram negative and gram positive strains were found to be decreasing yearwise with a trend towards an

Assessment of veterinary drug use and determination of ...

African Journals Online (AJOL)

A cross-sectional study was conducted between October 2009 and January 2010 to assess veterinary drug usage by broiler chicken farmers and to determine antimicrobial residues in broiler meat in Urban district, Zanzibar, Tanzania. Fifty five smallholder farmers were interviewed on types of antimicrobials, reasons for use, ...

Spectrum of microbial growth and antimicrobial usage in an ...

African Journals Online (AJOL)

Intensive-care units (ICUs) are a source of multidrug-resistant organisms, owing to the indiscriminate usage of broad-spectrum antimicrobial drugs. In such ... Staphylococcus aureus was the most common isolate from blood and central venous lines, and Pseudomonas aeruginosa from tracheal aspirates and wound swabs.

A comparison of antimicrobial usage in human and veterinary medicine in France from 1999 to 2005.

Science.gov (United States)

Moulin, Gérard; Cavalié, Philippe; Pellanne, Isabelle; Chevance, Anne; Laval, Arlette; Millemann, Yves; Colin, Pierre; Chauvin, Claire

2008-09-01

The antimicrobials allowed and amounts sold in veterinary and human medicine in France were compared to see if the same antimicrobial drugs are used in veterinary and human medicine, and to the same extent. Registers of all approved antimicrobial commercial products, kept by the French Agency for Veterinary Medicinal Products (AFSSA ANMV) for animals and the French Health Products Safety Agency (AFSSAPS) for humans, were compared to determine whether the same antimicrobials were approved in 2007 for use in both human and animal populations. Sales data were collected from pharmaceutical companies between 1999 and 2005 by the AFSSA ANMV and AFSSAPS. Usage of the different antimicrobial anatomical therapeutic chemical (ATC) classes in human and veterinary medicines was recorded. Data were expressed in tonnes of active ingredients and were then related to the animal and human biomasses to compare usages expressed in mg/kg. All antimicrobial ATC classes were used in both human and veterinary medicine. Tetracyclines accounted for the most sales in veterinary medicine. beta-Lactams predominated in human medicine. A decrease in the amounts consumed by both human and animal populations was observed during the study. In 2005, 760 tonnes were used in human medicine and 1320 tonnes in veterinary medicine, corresponding to 199 and 84 mg/kg of live weight in human and animal populations, respectively. The same antimicrobial drugs were used in human and veterinary medicines but the quantitative patterns of use were different. Expression of antimicrobial usage is a key point to address when comparing usage trends.

THE STRATEGY OF ANTIMICROBIAL THERAPY OF ACUTE UNCOMPLICATED PYELONEPHRITIS FROM THE POSITION OF ETIOLOGICAL DATA

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A. D. Kaprin

2015-01-01

Full Text Available Abstract:Acute pyelonephritis is one of the common diseases both in outpatient and in the hospital practice. The leading causative agent of this disease is E. coli. Obstructive uropathy, foreign body, vesicoureteral reflux, sexual activity, use of local contraceptives contribute to the upward development of urinary infection. The goals of antimicrobial therapy for acute uncomplicated pyelonephritis are: relief of symptoms, restoration of social activity, prevention of complications and relapse prevention. The choice of an antimicrobial agent in most cases is carried out empirically based on the data on the dominant pathogens and their regional resistance. In acute uncomplicated pyelonephritis duration of antimicrobial therapy should be 7–14 days. The drugs of choice for treatment of acute uncomplicated pyelonephritis non-severe in adults are ciprofloxacin and levofloxacin, ceftibuten and cefixime. Patients with acute uncomplicated pyelonephritis severe emergency hospitalization is shown in urological outpatient and parenteral antimicrobial therapy (carbapenems or protected aminopenicillins combined with or without amikacin with subsequent conversion to oral drugs and infusion therapy.

Effect of BMAP-28 antimicrobial peptides on Leishmania major promastigote and amastigote growth

DEFF Research Database (Denmark)

Lynn, Miriam A.; Kindrachuk, Jason; Marr, Alexandra K.

2011-01-01

Background: Protozoan parasites, such as Leishmania, still pose an enormous public health problem in many countries throughout the world. Current measures are outdated and have some associated drug resistance, prompting the search into novel therapies. Several innovative approaches are under...... of the cathelicidin family of HDPs have demonstrated significant antimicrobial activities against various parasites including Leishmania. The cathelicidin bovine myeloid antimicrobial peptide 28 (BMAP-28) has broad antimicrobial activities and confers protection in animal models of bacterial infection or sepsis. We...... with early osmotic cell lysis caused by the antimicrobial peptides. Furthermore, BMAP-28 and its isomers demonstrated anti-leishmanial activities against intracellular amastigotes within a macrophage infection model. Conclusions/Significance: Interestingly, D-BMAP-28 appears to be the most potent...

Size-dependent antimicrobial properties of the cobalt ferrite nanoparticles

Science.gov (United States)

Žalnėravičius, Rokas; Paškevičius, Algimantas; Kurtinaitiene, Marija; Jagminas, Arūnas

2016-10-01

The growing resistance of bacteria to conventional antibiotics elicited considerable interest to non-typical drugs. In this study, antimicrobial investigations were performed on low-size dispersion cobalt ferrite nanoparticles (Nps) fabricated by co-precipitation approach in several average sizes, in particular, 15.0, 5.0, and 1.65 nm. A variety of experimental tests demonstrated that the size of these Nps is determinant for antimicrobial efficiency against S. cerevisiae and several Candida species, in particular, C. parapsilosis, C. krusei, and C. albicans. The small and ultra-small fractions of CoFe2O4 Nps possess especially strong antimicrobial activity against all tested microorganisms. The possible reasons are discussed. Nps were characterized by means of transmission and high-resolution transmission electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy and atomic force microscopy, chemical analysis and magnetic measurements.

Size-dependent antimicrobial properties of the cobalt ferrite nanoparticles

International Nuclear Information System (INIS)

Žalnėravičius, Rokas; Paškevičius, Algimantas; Kurtinaitiene, Marija; Jagminas, Arūnas

2016-01-01

The growing resistance of bacteria to conventional antibiotics elicited considerable interest to non-typical drugs. In this study, antimicrobial investigations were performed on low-size dispersion cobalt ferrite nanoparticles (Nps) fabricated by co-precipitation approach in several average sizes, in particular, 15.0, 5.0, and 1.65 nm. A variety of experimental tests demonstrated that the size of these Nps is determinant for antimicrobial efficiency against S. cerevisiae and several Candida species, in particular, C. parapsilosis, C. krusei, and C. albicans. The small and ultra-small fractions of CoFe_2O_4 Nps possess especially strong antimicrobial activity against all tested microorganisms. The possible reasons are discussed. Nps were characterized by means of transmission and high-resolution transmission electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy and atomic force microscopy, chemical analysis and magnetic measurements.Graphical Abstract

Chitosan-based nanosystems and their exploited antimicrobial activity.

Science.gov (United States)

Perinelli, Diego Romano; Fagioli, Laura; Campana, Raffaella; Lam, Jenny K W; Baffone, Wally; Palmieri, Giovanni Filippo; Casettari, Luca; Bonacucina, Giulia

2018-05-30

Chitosan is a biodegradable and biocompatible natural polysaccharide that has a wide range of applications in the field of pharmaceutics, biomedical, chemical, cosmetics, textile and food industry. One of the most interesting characteristics of chitosan is its antibacterial and antifungal activity, and together with its excellent safety profile in human, it has attracted considerable attention in various research disciplines. The antimicrobial activity of chitosan is dependent on a number of factors, including its molecular weight, degree of deacetylation, degree of substitution, physical form, as well as structural properties of the cell wall of the target microorganisms. While the sole use of chitosan may not be sufficient to produce an adequate antimicrobial effect to fulfil different purposes, the incorporation of this biopolymer with other active substances such as drugs, metals and natural compounds in nanosystems is a commonly employed strategy to enhance its antimicrobial potential. In this review, we aim to provide an overview on the different approaches that exploit the antimicrobial activity of chitosan-based nanosystems and their applications, and highlight the latest advances in this field. Copyright © 2018 Elsevier B.V. All rights reserved.

NSAIDs: can the presence of infectious agent influence the choice of analgesic drug?

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О. А. Podpletnya

2017-08-01

Full Text Available Purpose. Considering the significant prevalence of comorbid pathology there is a high probability of NSAID use in patients with concomitant infection. In view of this screening of antimicrobial properties of their main groups was conducted for the purpose of selecting the most promising ones for further in-depth study. Materials and methods. The study of microorganisms’ sensitivity was conducted using standard research methods – the method of "wells" and by determining the antibacterial properties of drugs, using tablets, based on the ability of the drug to diffuse into agar, used for sowing the test-culture. As the test cultures S. aureus, S. mutans, S. pyogenes, P. aeruginosa, E. Coli, isolated from patients who were treated in hospital were used. Predominant blocker of COX-1 (acetylsalicylic acid, ASA, nonselective blockers of COX-1 and COX-2 (ketorolac, diclofenac sodium, ibuprofen, mefenamic acid, dexketoprofen, predominant blockers of COX-2 (meloxicam and nimesulide, selective blockers of COX-2 (celecoxib, selective blockers of COX-3 (COX-1 in the brain paracetamol and metamizole were tested. Results. The studies found that most of the tested NSAIDs have antimicrobial activity. Leader drugs in expressiveness of antimicrobial effects are drugs that have sufficient COX-1 (3 - activity: ASA, diclofenac, dexketoprofen, metamizole, and lesser extent – paracetamol. Tested NSAIDs showed the highest activity against gram-positive coccal flora, mostly affecting S. Pyogenes. Blockers of COX-3 paracetamol and metamizole, unlike other studied drugs, showed stronger antipseudomonal (both – moderate and antistaphylococcal action (metamizole. Conclusions. NSAIDs with antimicrobial activity can potentially increase the activity of antiinfectious therapy. At the same time, the antimicrobial activity of NSAIDs, theoretically, can promote microbial resistance because of existence of microorganisms in a medium with subthreshold concentrations of drugs

Plant-Derived Antimicrobials: Insights into Mitigation of Antimicrobial Resistance

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Shun-Kai Yang

2018-07-01

Full Text Available Antibiotic resistance had first been reported not long after the discovery of the first antibiotic and has remained a major public health issue ever since. Challenges are constantly encountered during the mitigation process of antibiotic resistance in the clinical setting; especially with the emergence of the formidable superbug, a bacteria with multiple resistance towards different antibiotics; this resulted in the term multidrug resistant (MDR bacteria. This rapid evolution of the resistance phenomenon has propelled researchers to continuously uncover new antimicrobial agents in a bid to hopefully, downplay the rate of evolution despite a drying pipeline. Recently, there has been a paradigm shift in the mining of potential antimicrobials; in the past, targets for drug discovery were from microorganisms and at current, the focus has moved onto plants, this is mainly due to the beneficial attributes that plants are able to confer over that of microorganisms. This review will briefly discuss antibiotic resistance mechanisms employed by resistant bacteria followed by a detailed expository regarding the use of secondary metabolites from plants as a potential solution to the MDR pathogen. Finally, future prospects recommending enhancements to the usage of plant secondary metabolites to directly target antibiotic resistant pathogens will be discussed.

Susceptibility of Aeromonas Hydophila Isolates to Antimicrobial Drugs

Directory of Open Access Journals (Sweden)

Igor Stojanov

2010-05-01

Full Text Available Aeromonas hydrophila is a microorganism widely distributed in nature: in water, soil, food. It is also part of the normal bacterial flora of many animals. As an opportune microorganism it is a secondary biological agent that contributes to the occurrence of a fish disease and its deterioration. Frequently, its presence is an indication of bad zoohygiene and zootechnical conditions in fish ponds. Reduced quality and quantity of feed, mechanical injuries, parasitosis, seasonal oscillation in temperature present some of the factors that produce favorable conditions for bacterial proliferation of aeromonas in fish ponds, so clinical symptoms of the disease occur. Aeromonas is almost always present in clinical isolates and may be unjustly accused for bad health of fish. Antibiotic therapy is applied even when the clinical findings are clear, what certainly effects the susceptibility to chemotherapeutics. The subject of our work was bacteriological examination of the material obtained from the carps with the observed skin changes and the carps without these changes. Also, antimicrobial susceptibility of Aeromonas hydrophila was tested. The aim of this research was to determined the presence of Aeromonas hydrophilia in the carp ponds and to test antibiotic susceptibility. The material consisted of the samples from the fish ponds where the carps were with and without changed skin. The method the isolation of Aeromonas hydrophila was used. The diffusion disk technique was used for testing antibiotic susceptibility. The isolates were tested for their susceptibility to Florephenikol, Flumequine, Olaqindox and Oxitetracycline. The obtained results point that antimicrobial susceptibility was the same regardless of the origin of the samples, i.e. the resistance was the same for both groups of samples (the strains isolated from the fish with skin changes and the strains from fish without changes on skin. The strains were highly resistant: 35% were resistant to

In vitro antimicrobial activity of five essential oils on multidrug resistant Gram-negative clinical isolates.

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Sakkas, Hercules; Gousia, Panagiota; Economou, Vangelis; Sakkas, Vassilios; Petsios, Stefanos; Papadopoulou, Chrissanthy

2016-01-01

The emergence of drug-resistant pathogens has drawn attention on medicinal plants for potential antimicrobial properties. The objective of the present study was the investigation of the antimicrobial activity of five plant essential oils on multidrug resistant Gram-negative bacteria. Basil, chamomile blue, origanum, thyme, and tea tree oil were tested against clinical isolates of Acinetobacter baumannii (n = 6), Escherichia coli (n = 4), Klebsiella pneumoniae (n = 7), and Pseudomonas aeruginosa (n = 5) using the broth macrodilution method. The tested essential oils produced variable antibacterial effect, while Chamomile blue oil demonstrated no antibacterial activity. Origanum, Thyme, and Basil oils were ineffective on P. aeruginosa isolates. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values ranged from 0.12% to 1.50% (v/v) for tea tree oil, 0.25-4% (v/v) for origanum and thyme oil, 0.50% to >4% for basil oil and >4% for chamomile blue oil. Compared to literature data on reference strains, the reported MIC values were different by 2SD, denoting less successful antimicrobial activity against multidrug resistant isolates. The antimicrobial activities of the essential oils are influenced by the strain origin (wild, reference, drug sensitive, or resistant) and it should be taken into consideration whenever investigating the plants' potential for developing new antimicrobials.

Challenges with gonorrhea in the era of multi-drug and extensively drug resistance – are we on the right track?

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Unemo, Magnus; Golparian, Daniel; Shafer, William M

2015-01-01

Neisseria gonorrhoeae has retained antimicrobial resistance to drugs previously recommended for first-line empiric treatment of gonorrhea, and resistance to ceftriaxone, the last option for monotherapy, is evolving. Crucial actions to combat this developing situation include implementing response plans; considering use of dual antimicrobial regimens; enhancing surveillance of gonorrhea, gonococcal antimicrobial resistance, treatment failures and antimicrobial use/misuse and improving prevention, early diagnosis, contact tracing and treatment. The ways forward also include an intensified research to identify novel antimicrobial resistance determinants and develop and evaluate appropriate use of molecular antimicrobial resistance testing, ideally point-of-care and with simultaneous detection of gonococci, to supplement culture-based methods and ideally guide tailored treatment. It is crucial with an enhanced understanding of the dynamics of the national and international emergence, transmission and evolution of antimicrobial-resistant gonococcal strains. Genome sequencing combined with epidemiological metadata will detail these issues and might also revolutionize the molecular antimicrobial resistance testing. Ultimately, novel antimicrobials are essential and some antimicrobials in development have shown potent in vitro activity against gonococci. Several of these antimicrobials deserve further attention for potential future treatment of gonorrhea. PMID:24702589

[Resistance of urinary tract pathogens and the choice of antimicrobial therapy: deceptive simplicity].

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Rafalskiy, V V; Dovgan, E V

2017-07-01

Urinary tract infection (UTI) is one of the most common reasons for prescribing antibiotics in outpatient and inpatient settings. One of the main criteria for selecting antimicrobial drugs for treating UTI is data on the antibiotic resistance of uropathogens. The article discusses the difficulties in interpreting the results of antimicrobial sensitivity testing of uropathogens and the impact of antibiotic resistance of uropathogens on the clinical effectiveness of managing UTI.

Redesigned Spider Peptide with Improved Antimicrobial and Anticancer Properties.

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Troeira Henriques, Sónia; Lawrence, Nicole; Chaousis, Stephanie; Ravipati, Anjaneya S; Cheneval, Olivier; Benfield, Aurélie H; Elliott, Alysha G; Kavanagh, Angela Maria; Cooper, Matthew A; Chan, Lai Yue; Huang, Yen-Hua; Craik, David J

2017-09-15

Gomesin, a disulfide-rich antimicrobial peptide produced by the Brazilian spider Acanthoscurria gomesiana, has been shown to be potent against Gram-negative bacteria and to possess selective anticancer properties against melanoma cells. In a recent study, a backbone cyclized analogue of gomesin was shown to be as active but more stable than its native form. In the current study, we were interested in improving the antimicrobial properties of the cyclic gomesin, understanding its selectivity toward melanoma cells and elucidating its antimicrobial and anticancer mode of action. Rationally designed analogues of cyclic gomesin were examined for their antimicrobial potency, selectivity toward cancer cells, membrane-binding affinity, and ability to disrupt cell and model membranes. We improved the activity of cyclic gomesin by ∼10-fold against tested Gram-negative and Gram-positive bacteria without increasing toxicity to human red blood cells. In addition, we showed that gomesin and its analogues are more toxic toward melanoma and leukemia cells than toward red blood cells and act by selectively targeting and disrupting cancer cell membranes. Preference toward some cancer types is likely dependent on their different cell membrane properties. Our findings highlight the potential of peptides as antimicrobial and anticancer leads and the importance of selectively targeting cancer cell membranes for drug development.

Public health risk of antimicrobial resistance transfer from companion animals.

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Pomba, Constança; Rantala, Merja; Greko, Christina; Baptiste, Keith Edward; Catry, Boudewijn; van Duijkeren, Engeline; Mateus, Ana; Moreno, Miguel A; Pyörälä, Satu; Ružauskas, Modestas; Sanders, Pascal; Teale, Christopher; Threlfall, E John; Kunsagi, Zoltan; Torren-Edo, Jordi; Jukes, Helen; Törneke, Karolina

2017-04-01

Antimicrobials are important tools for the therapy of infectious bacterial diseases in companion animals. Loss of efficacy of antimicrobial substances can seriously compromise animal health and welfare. A need for the development of new antimicrobials for the therapy of multiresistant infections, particularly those caused by Gram-negative bacteria, has been acknowledged in human medicine and a future corresponding need in veterinary medicine is expected. A unique aspect related to antimicrobial resistance and risk of resistance transfer in companion animals is their close contact with humans. This creates opportunities for interspecies transmission of resistant bacteria. Yet, the current knowledge of this field is limited and no risk assessment is performed when approving new veterinary antimicrobials. The objective of this review is to summarize the current knowledge on the use and indications for antimicrobials in companion animals, drug-resistant bacteria of concern among companion animals, risk factors for colonization of companion animals with resistant bacteria and transmission of antimicrobial resistance (bacteria and/or resistance determinants) between animals and humans. The major antimicrobial resistance microbiological hazards originating from companion animals that directly or indirectly may cause adverse health effects in humans are MRSA, methicillin-resistant Staphylococcus pseudintermedius, VRE, ESBL- or carbapenemase-producing Enterobacteriaceae and Gram-negative bacteria. In the face of the previously recognized microbiological hazards, a risk assessment tool could be applied in applications for marketing authorization for medicinal products for companion animals. This would allow the approval of new veterinary medicinal antimicrobials for which risk levels are estimated as acceptable for public health. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For

Antimicrobial biosurfactants from marine Bacillus circulans: extracellular synthesis and purification.

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Mukherjee, S; Das, P; Sivapathasekaran, C; Sen, R

2009-03-01

To purify the biosurfactant produced by a marine Bacillus circulans strain and evaluate the improvement in surface and antimicrobial activities. The study of biosurfactant production by B. circulans was carried out in glucose mineral salts (GMS) medium using high performance thin layer chromatography (HPTLC) for quantitative estimation. The biosurfactant production by this strain was found to be growth-associated showing maximum biosurfactant accumulation at 26 h of fermentation. The crude biosurfactants were purified using gel filtration chromatography with Sephadex G-50 matrix. The purification attained by employing this technique was evident from UV-visible spectroscopy and TLC analysis of crude and purified biosurfactants. The purified biosurfactants showed an increase in surface activity and a decrease in critical micelle concentration values. The antimicrobial action of the biosurfactants was also enhanced after purification. The marine B. circulans used in this study produced biosurfactants in a growth-associated manner. High degree of purification could be obtained by using gel filtration chromatography. The purified biosurfactants showed enhanced surface and antimicrobial activities. The antimicrobial biosurfactant produced by B. circulans could be effectively purified using gel filtration and can serve as new potential drugs in antimicrobial chemotherapy.

Screening of antimicrobial potential of in vitro calli and adult leaf ...

African Journals Online (AJOL)

pc

2013-02-27

Feb 27, 2013 ... varying inhibitory action against the test organisms. ... methods could lead to maintain bioactive potential of plants and to formulate antimicrobial drugs of .... aerogenes (Gram negative bacteria) and a fungus, Candida albicans ...

Use of antimicrobials in veterinary medicine and mechanisms of resistance.

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Schwarz, S; Chaslus-Dancla, E

2001-01-01

This review deals with the application of antimicrobial agents in veterinary medicine and food animal production and the possible consequences arising from the widespread and multipurpose use of antimicrobials. The various mechanisms that bacteria have developed to escape the inhibitory effects of the antimicrobials most frequently used in the veterinary field are reported in detail. Resistance of bacteria to tetracyclines, macrolide-lincosamide-streptogramin antibiotics, beta-lactam antibiotics, aminoglycosides, sulfonamides, trimethoprim, fluoroquinolones and chloramphenicol/florfenicol is described with regard to enzymatic inactivation, decreased intracellular drug accumulation and modification/protection/replacement of the target sites. In addition, basic information is given about mobile genetic elements which carry the respective resistance genes, such as plasmids, transposons, and gene cassettes/integrons, and their ways of spreading via conjugation, mobilisation, transduction, and transformation.

Reduction of the use of antimicrobial drugs following the rapid detection of Streptococcus agalactiae in the vagina at delivery by real-time PCR assay.

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Poncelet-Jasserand, E; Forges, F; Varlet, M-N; Chauleur, C; Seffert, P; Siani, C; Pozzetto, B; Ros, A

2013-08-01

To assess whether the determination of the presence of group B streptococci (GBS) in the vagina using a rapid polymerase chain reaction (PCR) assay at delivery was able to spare useless antimicrobial treatments, as compared with conventional culture at 34-38 weeks of gestation. Practical evaluation and prospective cost-effectiveness analysis. A university hospital in France. A cohort of 225 women in labour at the University-Hospital of Saint-Etienne. Each woman had a conventional culture performed at 34-38 weeks of gestation. At the beginning of labour, two vaginal swabs were sampled for rapid PCR testing and culture. The decision to prescribe a prophylactic antimicrobial treatment or not was taken according to the result of the PCR test. A comparative cost-effectiveness analysis of the two diagnostic strategies was carried out. Number of women receiving inadequate prophylactic antimicrobial drugs following each testing strategy, costs of PCR testing and culture, frequency of vaginal GBS, and diagnostic performance of the PCR test at delivery. The percentage of unnecessarily treated women was significantly reduced using the rapid test versus conventional culture (4.5 and 13.6%, respectively; P < 0.001). The rate of vaginal GBS at delivery was 12.5%. The incremental cost-effectiveness ratio (ICER) for each inadequate management avoided was €36 and €173 from the point of view of the healthcare system and hospital, respectively. The PCR assay reduced the number of inadequate antimicrobial treatments aimed to prevent the early onset of GBS disease. However, this strategy generates extra costs that must be put into balance with its clinical benefits. © 2013 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2013 RCOG.

Role of Nutrients and Phyto-compounds in the Modulation of Antimicrobial Resistance.

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Harakeh, Steve; Khan, Imran; Almasaudi, Saad B; Azhar, Esam I; Al-Jaouni, Soad; Niedzweicki, Aleksandra

2017-01-01

Antimicrobial resistance is quickly spreading and has become a major public health problem worldwide. If this issue is not resolved, it may cause a shift back to the pre-antibiotics era and infectious disease will again be a serious problem, especially in developing countries. Since the discovery of antibiotics, bacterial resistance has emerged, enabling certain bacteria to withstand antibiotic action. The emergence of antibiotic resistance is fueled by excessive and improper use of antimicrobial agents, especially in developing countries. For this reason, alternatives to or modifications of current treatment methods have been sought. The aim of this review is to highlight the possible synergies of various agents that can augment antibiotic activities. A structured literature search was conducted using only papers that have been published in PubMed with the focus on the agents that are likely to modulate antimicrobial resistance. In this review, data was retrieved from the literature regarding the possible synergies that exist between commercially available antimicrobial drugs with agents of interest. The papers included were summarized and analyzed, critiqued and compared for their contents using a conceptual frame-work. In total, one hundred and twenty six papers were reviewed. The number of papers that dealt with the different topics included are as follows (): emergence of antimicrobial resistance (22), bioactive phyto-compounds (36) (phytobiologics, and phytochemicals), Antioxidants (40) (N-acetylcysteine, Ambroxol, Ascorbic acid, Glutathione and vitamin E), Peptide synergies (14) (Synthetic cationic α-helical AMPs, CopA3, Alafosfalin, PMAP-36, Phosphonopeptide L-norvalyl-L-1-aminoethylphosphonic acid and norcardicin-A), nano-antibiotics (10), drug-compound interactions (4).This review addressed the new strategies using the above compounds in the modulation of antimicrobial resistance to avoid issues related to resistance of bacteria to antibiotics. The

Antimicrobial resistance trends among Escherichia coli isolates obtained from dairy cattle in the northeastern United States, 2004-2011.

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Cummings, Kevin J; Aprea, Victor A; Altier, Craig

2014-01-01

Monitoring antimicrobial resistance trends among bacteria isolated from food animals and people is necessary to inform risk analyses and guide public policy regarding antimicrobial use. Our objectives were to describe the antimicrobial resistance status of Escherichia coli isolates from dairy cattle in the northeastern United States and to identify trends in resistance to selected antimicrobial agents over time. We collected data retrospectively for all bovine E. coli isolates that were obtained from samples submitted to Cornell University's Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. We investigated temporal trends in the prevalence of resistant E. coli for each antimicrobial agent using the Cochran-Armitage trend test. Antimicrobial susceptibility testing was performed on 3373 bovine E. coli isolates from clinical samples submitted during the study period. Overall resistance to each antimicrobial agent ranged from 2.7% (enrofloxacin) to 91.3% (oxytetracycline). There was evidence of a significantly decreasing trend in prevalence of resistance to several agents: chlortetracycline, florfenicol, neomycin, oxytetracycline, spectinomycin, and trimethoprim/sulfamethoxazole. However, a significantly increasing trend in prevalence of resistance to enrofloxacin was also evident. These results do not support the idea that current antimicrobial use practices on dairy operations are driving a general increase in the emergence and dissemination of drug-resistant E. coli in the region served by the laboratory. However, resistance to some drugs remained consistently high during the study period, and increasing resistance to enrofloxacin is a key area of concern.

Antimicrobial drugs for persistent diarrhoea of unknown or non-specific cause in children under six in low and middle income countries: systematic review of randomized controlled trials

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Hart C Anthony

2009-03-01

Full Text Available Abstract Background A high proportion of children with persistent diarrhoea in middle and low income countries die. The best treatment is not clear. We conducted a systematic review to evaluate the effectiveness of antimicrobial drug treatment for persistent diarrhoea of unknown or non-specific cause. Methods We included randomized comparisons of antimicrobial drugs for the treatment of persistent diarrhoea of unknown or non-specific cause in children under the age of six years in low and middle income countries. We searched the electronic databases MEDLINE, EMBASE, LILACS, WEB OF SCIENCE, and the Cochrane Central Register of Controlled Trials (CENTRAL to May 2008 for relevant randomized or quasi randomized controlled trials. We summarised the characteristics of the eligible trials, assessed their quality using standard criteria, and extracted relevant outcomes data. Where appropriate, we combined the results of different trials. Results Three trials from South East Asia and one from Guatemala were included, all were small, and three had adequate allocation concealment. Two were in patients with diarrhoea of unknown cause, and two were in patients in whom known bacterial or parasitological causes of diarrhoea had been excluded. No difference was demonstrated for oral gentamicin compared with placebo (presence of diarrhoea at 6 or 7 days; 2 trials, n = 151; and for metronidazole compared with placebo (presence of diarrhoea at 3, 5 and 7 days; 1 trial, n = 99. In one small trial, sulphamethoxazole-trimethoprim appeared better than placebo in relation to diarrhoea at seven days and total stool volume (n = 55. Conclusion There is little evidence as to whether or not antimicrobials help treat persistent diarrhoea in young children in low and middle income countries.

Antimicrobial drugs for persistent diarrhoea of unknown or non-specific cause in children under six in low and middle income countries: systematic review of randomized controlled trials

Science.gov (United States)

2009-01-01

Background A high proportion of children with persistent diarrhoea in middle and low income countries die. The best treatment is not clear. We conducted a systematic review to evaluate the effectiveness of antimicrobial drug treatment for persistent diarrhoea of unknown or non-specific cause. Methods We included randomized comparisons of antimicrobial drugs for the treatment of persistent diarrhoea of unknown or non-specific cause in children under the age of six years in low and middle income countries. We searched the electronic databases MEDLINE, EMBASE, LILACS, WEB OF SCIENCE, and the Cochrane Central Register of Controlled Trials (CENTRAL) to May 2008 for relevant randomized or quasi randomized controlled trials. We summarised the characteristics of the eligible trials, assessed their quality using standard criteria, and extracted relevant outcomes data. Where appropriate, we combined the results of different trials. Results Three trials from South East Asia and one from Guatemala were included, all were small, and three had adequate allocation concealment. Two were in patients with diarrhoea of unknown cause, and two were in patients in whom known bacterial or parasitological causes of diarrhoea had been excluded. No difference was demonstrated for oral gentamicin compared with placebo (presence of diarrhoea at 6 or 7 days; 2 trials, n = 151); and for metronidazole compared with placebo (presence of diarrhoea at 3, 5 and 7 days; 1 trial, n = 99). In one small trial, sulphamethoxazole-trimethoprim appeared better than placebo in relation to diarrhoea at seven days and total stool volume (n = 55). Conclusion There is little evidence as to whether or not antimicrobials help treat persistent diarrhoea in young children in low and middle income countries. PMID:19257885

Anti-microbial and anti-biofilm compounds from Indonesian medicinal plants

NARCIS (Netherlands)

Pratiwi, Sylvia U.T.

2015-01-01

Microbial biofilms causing elevated resistance to both most anti-microbial drugs and the host defense systems, which often results in persistent and difficult-to-treat infections. The discovery of anti-infective agents which are active against planktonic and biofilm microorganisms are therefore

Antimicrobial activity of photo-activated cow urine against certain ...

African Journals Online (AJOL)

ONOS

2010-01-25

Jan 25, 2010 ... cow urine has shown 32 to 36 mm inhibition zone diameter homogeneously against all bacterial strains. It proves very high antimicrobial ... For control of microbial infections and diseases, various synthetic drugs and chemical ..... Protein and amino acid metabolism in the intestinal tract of growing bulls.

Size-dependent antimicrobial properties of the cobalt ferrite nanoparticles

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Žalnėravičius, Rokas [State Research Institute Center for Physical Sciences and Technology (Lithuania); Paškevičius, Algimantas [Nature Research Centre, Laboratory of Biodeterioration Research (Lithuania); Kurtinaitiene, Marija; Jagminas, Arūnas, E-mail: arunas.jagminas@ftmc.lt [State Research Institute Center for Physical Sciences and Technology (Lithuania)

2016-10-15

The growing resistance of bacteria to conventional antibiotics elicited considerable interest to non-typical drugs. In this study, antimicrobial investigations were performed on low-size dispersion cobalt ferrite nanoparticles (Nps) fabricated by co-precipitation approach in several average sizes, in particular, 15.0, 5.0, and 1.65 nm. A variety of experimental tests demonstrated that the size of these Nps is determinant for antimicrobial efficiency against S. cerevisiae and several Candida species, in particular, C. parapsilosis, C. krusei, and C. albicans. The small and ultra-small fractions of CoFe{sub 2}O{sub 4} Nps possess especially strong antimicrobial activity against all tested microorganisms. The possible reasons are discussed. Nps were characterized by means of transmission and high-resolution transmission electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy and atomic force microscopy, chemical analysis and magnetic measurements.Graphical Abstract.

Anti-biofilm and antimicrobial activity of Mentha pulegium L essential ...

African Journals Online (AJOL)

Purpose: To investigate the antimicrobial and anti-biofilm activities of essential oil from Mentha pulegieum L. (EOMP) on multi-drug resistant (MDR) isolates of A. baumannii, as well as its phytochemical composition, antioxidant properties and cytotoxic activity. Methods: The phytochemical composition of EOMP was ...

Antimicrobials Treatment

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Drosinos, Eleftherios H.; Skandamis, Panagiotis N.; Mataragas, Marios

The use of antimicrobials is a common practice for preservation of foods. Incorporation, in a food recipe, of chemical antimicrobials towards inhibition of spoilage and pathogenic micro-organisms results in the compositional modification of food. This treatment is nowadays undesirable for the consumer, who likes natural products. Scientific community reflecting consumers demand for natural antimicrobials has made efforts to investigate the possibility to use natural antimicrobials such us bacteriocins and essential oils of plant origin to inhibit microbial growth.

Antioxidant, Antigenotoxic, Antimicrobial Activities and Phytochemical Analysis of Dianthus carmelitarum

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Rezzan Aliyazicioglu

2017-05-01

Full Text Available In this study, we investigated the phytochemical composition, antioxidant, antimicrobial, and antigenotoxic properties of the aqueous extract of Dianthus carmelitarum for the first time. The phenolic and volatile compounds, antioxidant, antimicrobial and antigenotoxic activities of the extract were determined by HPLC and SPME-GC-FID/MS, spectrophotometric, agar well diffusion methods and comet assay, respectively. The polyphenolic content and ferric reducing power values of the extract were found 12.6 ± 0.27 mg gallic acid and 238 ± 2.89 μM trolox equivalents per g sample, respectively. Syringaldehyde and chlorogenic acid were detected as major phenolic compounds, while terpenes were determined as major volatile compound. Dianthus carmelitarum extract especially exhibited moderate antimicrobial activity against Mycobacterium smegmatis. Extract reduced H 2O 2-induced DNA damage in a concentration dependent manner in fibroblast cells compared to positive control (only 20 μM H 2O 2 treatment. Dianthus carmelitarum can be considered in the food, cosmetic, and drug industries due to its antioxidant, antimicrobial, and antigenotoxic activities.

Optimization and high-throughput screening of antimicrobial peptides.

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Blondelle, Sylvie E; Lohner, Karl

2010-01-01

While a well-established process for lead compound discovery in for-profit companies, high-throughput screening is becoming more popular in basic and applied research settings in academia. The development of combinatorial libraries combined with easy and less expensive access to new technologies have greatly contributed to the implementation of high-throughput screening in academic laboratories. While such techniques were earlier applied to simple assays involving single targets or based on binding affinity, they have now been extended to more complex systems such as whole cell-based assays. In particular, the urgent need for new antimicrobial compounds that would overcome the rapid rise of drug-resistant microorganisms, where multiple target assays or cell-based assays are often required, has forced scientists to focus onto high-throughput technologies. Based on their existence in natural host defense systems and their different mode of action relative to commercial antibiotics, antimicrobial peptides represent a new hope in discovering novel antibiotics against multi-resistant bacteria. The ease of generating peptide libraries in different formats has allowed a rapid adaptation of high-throughput assays to the search for novel antimicrobial peptides. Similarly, the availability nowadays of high-quantity and high-quality antimicrobial peptide data has permitted the development of predictive algorithms to facilitate the optimization process. This review summarizes the various library formats that lead to de novo antimicrobial peptide sequences as well as the latest structural knowledge and optimization processes aimed at improving the peptides selectivity.

Antimicrobial properties of nudibranchs tissues extracts from South Andaman, India

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Kota Veeraswamy Reddy

2015-07-01

Full Text Available Objective: To evaluate the antimicrobial properties of tissues extracts of different nudibranchs such as Phyllidia varicosa, Plakobranchus ocellatus, Phyllidiella rosans and Halgerda stricklandi against bacterial and fungal pathogens. Methods: Nudibranchs tissue samples were subjected to organic solvent extraction for antimicrobial activity by well diffusion method. Results: The crude extract 50 μL (0.2 mg of Phyllidia varicosa showed the maximum inhibitory zone (22 mm against Shigella flexneri. Plakobranchus ocellatus extract of 50 μL (0.2 mg showed the maximum inhibitory zone against Shigella flexneri (22 mm and Staphylococcus aureus (19 mm and no significant activity was found against the fungal pathogens. Conclusions: This work reveals that nudibranch tissues contain the antimicrobial secondary metabolites, which leads the significant activity against bacterial pathogens and further emphasizes detailed study on novel drug discovery from nudibranch tissues against certain human bacterial infections.

Antimicrobial and biophysical properties of surfactant supplemented with an antimicrobial peptide for treatment of bacterial pneumonia.

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Banaschewski, Brandon J H; Veldhuizen, Edwin J A; Keating, Eleonora; Haagsman, Henk P; Zuo, Yi Y; Yamashita, Cory M; Veldhuizen, Ruud A W

2015-01-01

Antibiotic-resistant bacterial infections represent an emerging health concern in clinical settings, and a lack of novel developments in the pharmaceutical pipeline is creating a "perfect storm" for multidrug-resistant bacterial infections. Antimicrobial peptides (AMPs) have been suggested as future therapeutics for these drug-resistant bacteria, since they have potent broad-spectrum activity, with little development of resistance. Due to the unique structure of the lung, bacterial pneumonia has the additional problem of delivering antimicrobials to the site of infection. One potential solution is coadministration of AMPs with exogenous surfactant, allowing for distribution of the peptides to distal airways and opening of collapsed lung regions. The objective of this study was to test various surfactant-AMP mixtures with regard to maintaining pulmonary surfactant biophysical properties and bactericidal functions. We compared the properties of four AMPs (CATH-1, CATH-2, CRAMP, and LL-37) suspended in bovine lipid-extract surfactant (BLES) by assessing surfactant-AMP mixture biophysical and antimicrobial functions. Antimicrobial activity was tested against methillicin-resistant Staphylococcus aureus and Pseudomonas aeruginosa. All AMP/surfactant mixtures exhibited an increase of spreading compared to a BLES control. BLES+CATH-2 mixtures had no significantly different minimum surface tension versus the BLES control. Compared to the other cathelicidins, CATH-2 retained the most bactericidal activity in the presence of BLES. The BLES+CATH-2 mixture appears to be an optimal surfactant-AMP mixture based on in vitro assays. Future directions involve investigating the potential of this mixture in animal models of bacterial pneumonia. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Antimicrobial use in Chinese swine and broiler poultry production.

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Krishnasamy, Vikram; Otte, Joachim; Silbergeld, Ellen

2015-01-01

Antimicrobial use for growth promotion in food animal production is now widespread. A major concern is the rise of antimicrobial resistance and the subsequent impact on human health. The antimicrobials of concern are used in concentrated animal feeding operations (CAFOs) which are responsible for almost all meat production including swine and poultry in the US. With global meat consumption rising, the CAFO model has been adopted elsewhere to meet this demand. One such country where this has occurred is China, and evidence suggests 70% of poultry production now occurs outside of traditional small farms. Moreover, China is now the largest aggregate consumer of meat products in the world. With this rapid rise in consumption, the Chinese production model has changed along with the use of antimicrobials in feeds. However, the specific antibiotic use in the Chinese food animal production sector is unclear. Additionally, we are aware of high quantities of antimicrobial use because of reports of high concentrations of antimicrobials in animal waste and surface waters surrounding animal feeding operations. In this report, we estimate the volume of antibiotics used for swine and poultry production as these are the two meat sources with the highest levels of production and consumption in China. We adopt a model developed by Mellon et al. in the US for estimating drug use in feed for poultry and swine production to estimate overall antimicrobial use as well as antimicrobial use by class. We calculate that 38.5 million kg [84.9 million lbs] were used in 2012 in China's production of swine and poultry. By antibiotic class, the highest weights are tetracyclines in swine and coccidiostats in poultry. The volume of antimicrobial use is alarming. Although there are limitations to these data, we hope our report will stimulate further analysis and a sense of urgency in assessing the consequences of such high levels of utilization in terms of antibiotic resistance in the food supply

Multiple Antimicrobial Resistance of Escherichia coli Isolated from Chickens in Iran.

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Talebiyan, Reza; Kheradmand, Mehdi; Khamesipour, Faham; Rabiee-Faradonbeh, Mohammad

2014-01-01

Antimicrobial agents are used extremely in order to reduce the great losses caused by Escherichia coli infections in poultry industry. In this study, 318 pathogenic Escherichia coli (APEC) strains isolated from commercial broiler flocks with coli-septicemia were examined for antimicrobials of both veterinary and human significance by disc diffusion method. Multiple resistances to antimicrobial agents were observed in all the isolates. Resistance to the antibiotics was as follows: Tylosin (88.68%), Erythromycin (71.70%), Oxytetracycline (43.40%), Sulfadimethoxine-Trimethoprim (39.62%), Enrofloxacin (37.74%), Florfenicol (35.85%), Chlortetracycline (33.96%), Doxycycline (16.98%), Difloxacin (32.08%), Danofloxacin (28.30%), Chloramphenicol (20.75%), Ciprofloxacin (7.55%), and Gentamicin (5.66%). This study showed resistance against the antimicrobial agents that are commonly applied in poultry, although resistance against the antibiotics that are only applied in humans or less frequently used in poultry was significantly low. This study emphasizes on the occurrence of multiple drug resistant E. coli among diseased broiler chickens in Iran. The data revealed the relative risks of using antimicrobials in poultry industry. It also concluded that use of antibiotics must be limited in poultry farms in order to reduce the antibiotic resistances.

Multiple Antimicrobial Resistance of Escherichia coli Isolated from Chickens in Iran

Directory of Open Access Journals (Sweden)

Reza Talebiyan

2014-01-01

Full Text Available Antimicrobial agents are used extremely in order to reduce the great losses caused by Escherichia coli infections in poultry industry. In this study, 318 pathogenic Escherichia coli (APEC strains isolated from commercial broiler flocks with coli-septicemia were examined for antimicrobials of both veterinary and human significance by disc diffusion method. Multiple resistances to antimicrobial agents were observed in all the isolates. Resistance to the antibiotics was as follows: Tylosin (88.68%, Erythromycin (71.70%, Oxytetracycline (43.40%, Sulfadimethoxine-Trimethoprim (39.62%, Enrofloxacin (37.74%, Florfenicol (35.85%, Chlortetracycline (33.96%, Doxycycline (16.98%, Difloxacin (32.08%, Danofloxacin (28.30%, Chloramphenicol (20.75%, Ciprofloxacin (7.55%, and Gentamicin (5.66%. This study showed resistance against the antimicrobial agents that are commonly applied in poultry, although resistance against the antibiotics that are only applied in humans or less frequently used in poultry was significantly low. This study emphasizes on the occurrence of multiple drug resistant E. coli among diseased broiler chickens in Iran. The data revealed the relative risks of using antimicrobials in poultry industry. It also concluded that use of antibiotics must be limited in poultry farms in order to reduce the antibiotic resistances.

Chitosan preparations for wounds and burns: antimicrobial and wound-healing effects

Science.gov (United States)

Dai, Tianhong; Tanaka, Masamitsu; Huang, Ying-Ying; Hamblin, Michael R

2011-01-01

Since its discovery approximately 200 years ago, chitosan, as a cationic natural polymer, has been widely used as a topical dressing in wound management owing to its hemostatic, stimulation of healing, antimicrobial, nontoxic, biocompatible and biodegradable properties. This article covers the antimicrobial and wound-healing effects of chitosan, as well as its derivatives and complexes, and its use as a vehicle to deliver biopharmaceuticals, antimicrobials and growth factors into tissue. Studies covering applications of chitosan in wounds and burns can be classified into in vitro, animal and clinical studies. Chitosan preparations are classified into native chitosan, chitosan formulations, complexes and derivatives with other substances. Chitosan can be used to prevent or treat wound and burn infections not only because of its intrinsic antimicrobial properties, but also by virtue of its ability to deliver extrinsic antimicrobial agents to wounds and burns. It can also be used as a slow-release drug-delivery vehicle for growth factors to improve wound healing. The large number of publications in this area suggests that chitosan will continue to be an important agent in the management of wounds and burns. PMID:21810057

Frequency of serovars and antimicrobial resistance in Shigella spp. from Brazil

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Gisele Peirano

2006-05-01

Full Text Available A total of 296 Shigella spp. were received from State Public Health Laboratories, during the period from 1999 to 2004, by National Reference Laboratory for Cholera and Enteric Diseases (NRLCED - IOC/Fiocruz, Rio de Janeiro, Brazil. The frequency of Shigella spp. was: S. flexneri (52.7%, S. sonnei (44.2%, S. boydii (2.3%, and S. dysenteriae (0.6%. The most frequent S. flexneri serovars were 2a and 1b. The highest incidence rates of Shigella isolation were observed in the Southeast (39% and Northeast (34% regions and the lowest rate in the South (3% of Brazil. Strains were further analyzed for antimicrobial susceptibility by disk diffusion method as part of a surveillance program on antimicrobial resistance. The highest rates of antimicrobial resistance were to trimethoprim-sulfamethozaxole (90%, tetracycline (88%, ampicillin (56%, and chloramphenicol (35%. The patterns of antimicrobial resistance among Shigella isolates pose a major difficulty in the determination of an appropriate drug for shigellosis treatment. Continuous monitoring of antimicrobial susceptibilities of Shigella spp. through a surveillance system is thus essential for effective therapy and control measures against shigellosis.

Antimicrobial treatment for early, limited Mycobacterium ulcerans infection : a randomised controlled trial

NARCIS (Netherlands)

Nienhuis, Willemien A.; Stienstra, Ymkje; Thompson, William A.; Awuah, Peter C.; Abass, K. Mohammed; Tuah, Wilson; Awua-Boateng, Nana Yaa; Ampadu, Edwin O.; Siegmund, Vera; Schouten, Jan P.; Adjei, Ohene; Bretzel, Gisela; van der Werf, Tjip S.

2010-01-01

Background Surgical debridement was the standard treatment for Mycobacterium ulcerans infection (Buruli ulcer disease) until WHO issued provisional guidelines in 2004 recommending treatment with antimicrobial drugs (streptomycin and rifampicin) in addition to surgery. These recommendations were

Antimicrobial effects of 14 Medicinal plant speices of Dashti in Bushehr province

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Afshin Shirkani

2014-04-01

Full Text Available Background: Medicinal plants are used in treating diseases as low-risk, available and inexpensive natural materials with higher consumption by people comparing to synthetic antimicrobial drugs. Excessive use of antimicrobial drugs led to medicinal resistance against different antibiotics in most bacteria. Material and Methods: In this empirical experimental study, the antimicrobial effects of methanolic extracts of 14 medicinal plants species were examined comparing to conventional therapeutic antibiotics against standard bacterial strains. The plant species were collected from dashti of Bushehr province.The methanolic extract of the cultivations broths were prepared in different concentrations (0/25%, 0/5%, 1%, 2% and 4% dissolved in DMSO/ Methanolic solution and their antibacterial potency respected on the inhibition zone using the disc diffusion assay. Results: The maximum effects on Escherichia coli belonged to Arundo donax and the least effects belonged to Calotropis procera. The maximum effects on Staphylococcus aureus belonged to Lawsonia inermis and the least effects belonged to Calotropis procera. The maximum effects on Micrococcus luteus belonged to Phoeniex doctylifera and the least effects belonged to Oligomeris baccatus. The maximum effects on Klebsiella pneumonia belonged to mnocarpos decander and the least effects belonged Oligomeris baccatus. The maximum effects on pseudomonas aeroginosa belonged to Arundo donax. The maximum effects on Bacillus subtilis belonged to Astragalus arbusculinus. Conclusion: The antimicrobial effects of 4% methanolic extracts of Arundo donax were comparable to Cephalotin (30mcg, Piperacilin (30mcg and Amikacin (30mcg against Escherichia coli and pseudomonas aeroginosa. The antimicrobial effects of %4 extracts of Lawsonia inermis were similar to Amikacin (30mcg and Chloramphenicol (30mcg against Klebsiella penumoniae.

In vivo selection of resistant E. coli after ingestion of milk with added drug residues.

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Richard Van Vleck Pereira

Full Text Available Antimicrobial resistance represents a major global threat to modern medicine. In vitro studies have shown that very low concentrations of drugs, as frequently identified in the environment, and in foods and water for human and animal consumption, can select for resistant bacteria. However, limited information is currently available on the in vivo impact of ingested drug residues. The objective of our study was to evaluate the effect of feeding preweaned calves milk containing antimicrobial drug residues (below the minimum inhibitory concentration, similar to concentrations detected in milk commonly fed to dairy calves, on selection of resistant fecal E. coli in calves from birth to weaning. At birth, thirty calves were randomly assigned to a controlled feeding trial where: 15 calves were fed raw milk with no drug residues (NR, and 15 calves were fed raw milk with drug residues (DR by adding ceftiofur, penicillin, ampicillin, and oxytetracycline at final concentrations in the milk of 0.1, 0.005, 0.01, and 0.3 µg/ml, respectively. Fecal samples were rectally collected from each calf once a week starting at birth prior to the first feeding in the trial (pre-treatment until 6 weeks of age. A significantly greater proportion of E. coli resistant to ampicillin, cefoxitin, ceftiofur, streptomycin and tetracycline was observed in DR calves when compared to NR calves. Additionally, isolates from DR calves had a significant decrease in susceptibility to ceftriaxone and ceftiofur when compared to isolates from NR calves. A greater proportion of E. coli isolates from calves in the DR group were resistant to 3 or more antimicrobial drugs when compared to calves in the ND group. These findings highlight the role that low concentrations of antimicrobial drugs have on the evolution and selection of resistance to multiple antimicrobial drugs in vivo.

Antimicrobial stewardship in a Gastroenterology Department: Impact on antimicrobial consumption, antimicrobial resistance and clinical outcome.

Science.gov (United States)

Bedini, Andrea; De Maria, Nicola; Del Buono, Mariagrazia; Bianchini, Marcello; Mancini, Mauro; Binda, Cecilia; Brasacchio, Andrea; Orlando, Gabriella; Franceschini, Erica; Meschiari, Marianna; Sartini, Alessandro; Zona, Stefano; Paioli, Serena; Villa, Erica; Gyssens, Inge C; Mussini, Cristina

2016-10-01

A major cause of the increase in antimicrobial resistance is the inappropriate use of antimicrobials. To evaluate the impact on antimicrobial consumption and clinical outcome of an antimicrobial stewardship program in an Italian Gastroenterology Department. Between October 2014 and September 2015 (period B), a specialist in infectious diseases (ID) controlled all antimicrobial prescriptions and decided about the therapy in agreement with gastroenterologists. The defined daily doses of antimicrobials (DDDs), incidence of MDR-infections, mean length of stay and overall in-hospital mortality rate were compared with those of the same period in the previous 12-months (period A). During period B, the ID specialist performed 304 consultations: antimicrobials were continued in 44.4% of the cases, discontinued in 13.8%, not recommended in 12.1%, de-escalated 9.9%, escalated in 7.9%, and started in 4.0%. Comparing the 2 periods, we observed a decreased of antibiotics consumption (from 109.81 to 78.45 DDDs/100 patient-days, p=0.0005), antifungals (from 41.28 to 24.75 DDDs/100pd, p=0.0004), carbapenems (from 15.99 to 6.80 DDDsx100pd, p=0.0032), quinolones (from 35.79 to 17.82 DDDsx100pd, p=0.0079). No differences were observed in incidence of MDR-infections, length of hospital stay (LOS), and mortality rate. ASP program had a positive impact on reducing the consumption of antimicrobials, without an increase in LOS and mortality. Copyright © 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Animation of Antimicrobial Resistance

Medline Plus

Full Text Available ... Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing options ... of Animation of Antimicrobial Resistance More in Antimicrobial ... Antimicrobial Resistance Monitoring System About NARMS 2015 NARMS Integrated ...

Prevalence of resistance to 11 antimicrobials among Campylobacter coill isolated from pigs on 80 grower-finisher farms in Ontario.

Science.gov (United States)

Varela, Norma P; Friendship, Robert; Dewey, Cate

2007-07-01

We carried out a cross-sectional study to investigate antimicrobial resistance patterns of Campylobacter coli isolated from Ontario grower-finisher pigs. From January to June 2004, 1200 samples were collected from 80 farms by obtaining a constant number (15) of fecal samples per farm. Susceptibility of the isolates to 11 antimicrobial drugs was determined by the agar-dilution technique. The overall prevalence of resistance to 1 or more antimicrobials among the isolates was 99.2%. High levels of resistance were observed for azithromycin, clindamycin, erythromycin, streptomycin, and tetracycline: 91.7%, 82.5%, 81.4%, 70.7%, and 63.7%, respectively. For sulfamethoxazole, ampicillin, and nalidixic acid, resistance was observed in 40.3%, 26.6%, and 22.7% of the isolates, respectively. Although at very low levels, resistance was observed for ciprofloxacin (a fluoroquinolone), chloramphenicol, and gentamicin: in 2.4%, 1.7%, and 0.2%, respectively. Many of the isolates (29.7%) were resistant to 5 antimicrobials, the most common being azithromycin, clindamycin, erythromycin, streptomycin, and tetracycline. Isolates from the same farm showed at least 5 patterns of resistance. Results from this study indicate high levels of resistance to the antimicrobial drugs most commonly used in the Canadian swine industry (macrolides, lincosamides, and tetracyclines) among C. coli isolated from grower-finisher pigs in Ontario. Macrolides and fluoroquinolones are the drugs most commonly used to treat severe human campylobacteriosis. Fortunately, at present, there is little resistance to fluoroquinolones among C. coli from pigs in Ontario.

The Phytochemical and Antimicrobial Properties of Entomopathogenic Fungi in Nueva Vizcaya, Philippines

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Fitzgerald L. Fabelico

2015-12-01

Full Text Available Entomopathogenicfungi (EPF are potential biocontrol agents against agricultural pests and insects. These fungi are also known to be a source of secondary metabolites and could be a potential source of antibiotic drugs in the future. This study aims to determine the phytochemical and antimicrobial properties of EPF isolated from different host insects and their larvae in the province of Nueva Vizcaya.The method employed in this study includes the collection of EPF from dead insects and their larvae, isolation and mass production of the fungi, identification of the different fungi, extraction of secondary metabolites from the fungi, phytochemical screening, and antimicrobial assay. The results revealed that the antimicrobial properties of the different EPF could be explained by their phytochemical properties.When compared to the positive control, the significantly high antifungal activities of the Pandora neoaphidis(EPF 1 against the Candida albicans can be due to the presence of sterols. Conversely, the significantly high antibacterial activities of Beauveria alba (EPF 5 against Bacillus subtiliscould be due to the presence ofsteroids, triterpenoids, glycosides, and fatty acids.These findings indicate that entomopathogenic fungi could be a potential source of antibiotic drugs against pathogenic microorganism in the near future. To realize this, future research is highly recommended for the isolation, elucidation, and evaluation of the safety of the bioactive compounds of entomopathogenic fungi responsible for the antimicrobial activities, prior to their use in humans.

Antimicrobial resistance in clinical Escherichia coli isolates from poultry and livestock, China.

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Afrah Kamal Yassin

Full Text Available Poultry and livestock are the most important reservoirs for pathogenic Escherichia coli and use of antimicrobials in animal farming is considered the most important factor promoting the emergence, selection and dissemination of antimicrobial-resistant microorganisms. The aim of our study was to investigate antimicrobial resistance in E. coli isolated from food animals in Jiangsu, China. The disc diffusion method was used to determine susceptibility to 18 antimicrobial agents in 862 clinical isolates collected from chickens, ducks, pigs, and cows between 2004 and 2012. Overall, 94% of the isolates showed resistance to at least one drug with 83% being resistance to at least three different classes of antimicrobials. The isolates from the different species were most commonly resistant to tetracycline, nalidixic acid, sulfamethoxazole, trimethoprim/sulfamethoxazole and ampicillin, and showed increasing resistance to amikacin, aztreonam, ceftazidime, cefotaxime, chloramphenicol, ciprofloxacin. They were least resistant to amoxicillin/clavulanic acid (3.4% and ertapenem (0.2%. MDR was most common in isolates from ducks (44/44, 100%, followed by chickens (568/644, 88.2%, pigs (93/113, 82.3% and cows (13/61, 21.3%. Our finding that clinical E. coli isolates from poultry and livestock are commonly resistant to multiple antibiotics should alert public health and veterinary authorities to limit and rationalize antimicrobial use in China.

Drug monitoring and individual dose optimization of antimicrobial drugs : oxazolidinones

NARCIS (Netherlands)

Cattaneo, Dario; Alffenaar, Jan-Willem; Neely, Michael

INTRODUCTION: Oxazolidinones are synthetic antibiotics with bacteriostatic activity against Gram-positive pathogens. Linezolid, the first marketed oxazolidinone, has shown also activity against Mycobaterium tuberculosis, including multidrug-resistant and extensively drug-resistant strains. Recently,

Improving antimicrobial prescribing in Irish primary care through electronic data collection and surveillance: a feasibility study.

Science.gov (United States)

Galvin, Sandra; Callan, Aoife; Cormican, Martin; Duane, Sinead; Bennett, Kathleen; Murphy, Andrew W; Vellinga, Akke

2015-07-02

The increase in the spread of antimicrobial resistance (AMR) in bacterial pathogens and limited availability of new antimicrobials places immense pressure on general practitioners (GPs) to prescribe appropriately. Currently, electronic antimicrobial prescribing data is not routinely collected from GPs in Ireland for surveillance purposes to assess regional specific fluctuations or trends in antimicrobial prescribing. The current study aimed to address this issue by assessing the feasibility of remotely extracting antimicrobial prescribing data from primary care practices in Ireland, for the purpose of assessing prescribing quality using the European Surveillance of Antimicrobial Consumption (ESAC) drug specific quality indicators. Participating practices (n = 30) uploaded data to the Irish Primary Care Research Network (IPCRN). The IPCRN data extraction facility is integrated within the practice patient management software system and permitted the extraction of anonymised patient prescriptions for a one year period, from October 2012 to October 2013. The quality of antimicrobial prescribing was evaluated using the twelve ESAC drug specific quality indicators using the defined daily dose (DDD) per 1,000 inhabitants per day (DID) methodology. National and European prescribing surveillance data (based on total pharmacy sales) was obtained for a comparative analysis. Antimicrobial prescriptions (n = 57,079) for 27,043 patients were obtained from the thirty study practices for a one year period. On average, study practices prescribed a greater proportion of quinolones (37 % increase), in summer compared with winter months, a variation which was not observed in national and European data. In comparison with national data, study practices prescribed higher proportions of β-lactamase-sensitive penicillins (4.98 % vs. 4.3 %) and a greater use of broad spectrum compared to narrow-spectrum antimicrobials (ratio = 9.98 vs. 6.26) was observed. Study practices exceeded the

Antimicrobial Activity of Some Medicinal Plant Extracts against Multidrug Resistant Bacteria

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Majid Masoumian

2017-11-01

Full Text Available Background: Nowadays, it is necessary to discover new and efficient antifungal or antimicrobial drugs because of increasing drug resistance organisms. Using medicinal plants for natural treatment of diseases caused by bacterial origin has mainly been considered. Objectives: In this study, the impacts of antimicrobial medicinal plants extract were compared based on four bacteria in vitro. Methods: In this experimental study, disc diffusion assay and the minimum inhibitory concentration (MIC method were used to investigate the antibacterial effects of selected plant extract elicited by two different solvent on S. aureus, E. coli, P. aeruginosa and S. enteric. Data were analyzed with a statistical software program (SPSS 16. Results: The hydro-alcoholic extract of Myrtus communis (myrtle and water extract of Cinnamomun zeylanicum (cinnamon were the most active extracts screened for antimicrobial activities against different four bacteria as tested organisms. The diameter of inhibition zones ranged from 23 to 28 mm. Comparison of the antibacterial effect of plant extracts and commercial drug revealed that the size of inhibition zone of penicillin against Staphylococcus aureus bacterium was larger than the plant extracts. However, myrtle extract at the minimum inhibitory concentration (MIC of 30 mg/mL showed more powerful antibacterial activity compared to the other extracts and even penicillin. Petroselinum crispum (parsley, Nerium oleander (Oleander and Glycyrihiza glabra (licorice were found to have the least effect on the tested bacteria. Conclusions: In the present study, plant extracts with different compounds showed antibacterial activity (especially myrtle and cinnamon. Hence, they can be used as new source for antibacterial substances.

Altered distribution of technetium-99m sodium pertechnetate associated with antimicrobial therapy

International Nuclear Information System (INIS)

Castronuovo, J.J.; Chervu, L.R.; Milstein, D.M.

1985-01-01

Three patients underwent brain scanning for evaluation of central nervous system disease and were simultaneously treated for infectious diseases unrelated to the central nervous process. All revealed intense vascular pooling on their brain images. The imaging studies had been performed following the administration of Tc-99m pertechnetate. None of the patients had prior nuclear medicine examinations to suggest the causal effect of stannous ion as a source of interference. All of the patients were on combination antimicrobial drugs: two on sulfamethoxazole and trimethoprim, and one on isoniazid and ethambutol. One patient revealed 75% Tc-99m red cell tagging. Another patient's repeat brain scan with Tc-99m DTPA revealed normal distribution. Our findings suggest that patients on antimicrobial combination drug regimens who require brain scans should be imaged routinely with agents other than Tc-99m

Survey of metals on antimicrobial and deodorant agents in household Necessities; Mukikei kokinsei kakoseihin no shiyojittai

Energy Technology Data Exchange (ETDEWEB)

Kan, Teruo

1999-11-01

It measured the metal bearing quantity in household necessities in order to clarify use actual condition of the metal system drug. And, it tried the detection of the drug used from detected metal. Too there is the report until now in the investigation of the metallic element in household necessities. However, metals examined this time are silver and zinc, four of copper and aluminum that it says that it has the antimicrobial action and is Key element of inorganic system antimicrobial agent. And, it carried out the analysis by inductive coupling plasma emission analysis method, after the wet digestion of the sample was done. (NEDO)

Label-free detection of biomolecular interaction — DNA — Antimicrobial peptide binding

DEFF Research Database (Denmark)

Fojan, Peter; Jensen, Kasper Risgaard; Gurevich, Leonid

2011-01-01

the molecule. In particular, surface plasmon resonance (SPR) sensors have been already demonstrated suitable for food-safety control, label-free screening for various disease markers in bodily fluids, as well as for real-time continuous monitoring of drug levels in intensive care environment. We envisage...... of plasmon based biosensors to the study of the interaction of Antimicrobial peptide IL4 and DNA. Our results indicate high affinity binding between IL4 and DNA thereby preventing DNA replication and eventually killing the affected cell. We speculate that this is common for a large class of Antimicrobial...

Synthesis of modified pyridine and bipyridine substituted coumarins as potent antimicrobial agents

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Lad Hemali B.

2015-01-01

Full Text Available In search for new antimicrobial agents a series of new modified pyridine and bipyridine substituted coumarins 5a-y was designed and synthesized by adopting molecular hybridization strategy. All the synthesized compounds were evaluated for their in vitro antimicrobial activity using broth dilution method against selected bacterial (Gram-positive and Gram-negative and fungal strains. Compounds 5a, 5f, 5g, 5n, 5r, 5t, 5w, 5x and 5y demonstrated promising antibacterial activity while other derivatives showed comparable activity to standard drugs used as reference.

Current and future challenges in the development of antimicrobial agents.

Science.gov (United States)

Rennie, Robert P

2012-01-01

Micro-organisms exist to survive. Even in the absence of antimicrobial agents, many have determinants of resistance that may be expressed phenotypically, should the need arise. With the advent of the antibiotic age, as more and more drugs were developed to treat serious infections, micro-organisms (particularly bacteria) rapidly developed resistance determinants to prevent their own demise.The most important determinants of resistance have been in the Gram-positive and Gram-negative bacteria. Among Gram-positive bacteria, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and penicillin-resistant Streptococcus pneumoniae (PRSP) have taxed researchers and pharmaceutical companies to develop new agents that are effective against these resistant strains. Among the Gram-negative bacteria, extended-spectrum beta-lactamase (ESBL) enzymes, carbapenemases (CREs) and the so-called amp-C enzymes that may be readily transferred between species of enterobacteriaceae and other facultative species have created multi-drug resistant organisms that are difficult to treat. Other resistance determinants have been seen in other clinically important bacterial species such as Neisseria gonorrhoeae, Clostridium difficile, Haemophilus influenzae and Mycobacterium tuberculosis. These issues have now spread to fungal agents of infection.A variety of modalities have been used to stem the tide of resistance. These include the development of niche compounds that target specific resistance determinants. Other approaches have been to find new targets for antimicrobial activity, use of combination agents that are effective against more than one target in the cell, or new delivery mechanism to maximize the concentration of antimicrobial agents at the site of infection without causing toxicity to the host. It is important that such new modalities have been proved effective for clinical therapy. Animal models and non-mammalian systems have been developed to

[Antimicrobial resistance of Bartonella bacilliformis strains from regions endemic to bartonellosis in Peru].

Science.gov (United States)

Mendoza-Mujica, Giovanna; Flores-León, Diana

2015-10-01

To evaluate in vitro antimicrobial susceptibility to chloramphenicol (CHL) and ciprofloxacin (CIP) in strains of Bartonella bacilliformis from areas that are endemic to Bartonellosis in Peru, through three laboratory methods. Antimicrobial susceptibility to CHL and CIP from 100 strains of Bartonella bacilliformis isolated in patients from the regions of Ancash, Cusco, Cajamarca, Lima and La Libertad were evaluated. Strains were evaluated by: disk diffusion, E-test and agar dilution. 26% of the strains of Bartonella bacilliformis evaluated were resistant to CIP and 1% to CHL. Similar patterns of antimicrobial sensitivity / resistance were obtained in all three methods. Bartonella bacilliformis strains circulating in Peru have high levels of in vitro resistance to CIP, so it is advisable to expand research on the use of drug treatment regimens of the Bartonellosis. The methods of E-test and disk diffusion were the most suitable for assessment in vitro of antimicrobial susceptibility of the microorganism.

Antimicrobial use in Danish pig herds with and without postweaning multisystemic wasting syndrome

DEFF Research Database (Denmark)

Jensen, Vibeke Frøkjær; Enøe, Claes; Wachmann, Henrik

2010-01-01

A retrospective cohort study was performed on 130 pig herds in Denmark, to assess the effect of PMWS on the use of antimicrobial drug. The study comprised 65 herds diagnosed with PMWS during 2003–2004, and matched by the veterinary practitioner with 65 herds free from PMWS. Information...... on antimicrobial use 1 year before and 1 year after the diagnosis was achieved from the National Prescription Medicine Monitoring Database, VetStat, and summarized on quarter within age group and herd. The multiple linear regression analysis comprised antimicrobial use as the outcome variable with (1) quarter...... relative to diagnosis of PMWS in the positive herd (same date for the negative match), (2) diagnosis of PMWS (same date used for matched PMWS(−) herd), (3) season and (4) temporal trend as fixed effects. Relative to the unaffected herds, the antimicrobial use in the sow units in the PMWS(+) herds...

Clinical pharmacokinetics of antimicrobial drugs in cystic fibrosis

NARCIS (Netherlands)

Touw, D J

The disposition of many drugs in cystic fibrosis is abnormal compared with healthy individuals. In general, changes include an increased volume of distribution expressed in liters per kg bodyweight for highly hydrophilic drugs such as aminoglycosides, and, to a lesser extent, for penicillins and

Metal oxide nanoparticles as antimicrobial agents: a promise for the future.

Science.gov (United States)

Raghunath, Azhwar; Perumal, Ekambaram

2017-02-01

Microbial infectious diseases are a global threat to human health. Excess and improper use of antibiotics has created antimicrobial-resistant microbes that can defy clinical treatment. The hunt for safe and alternate antimicrobial agents is on in order to overcome such resistant micro-organisms, and the birth of nanotechnology offers promise to combat infectious organisms. Over the past two decades, metal oxide nanoparticles (MeO-NPs) have become an attractive alternative source to combat microbes that are highly resistant to various classes of antibiotics. Their vast array of physicochemical properties enables MeO-NPs to act as antimicrobial agents through various mechanisms. Apart from exhibiting antimicrobial properties, MeO-NPs also serve as carriers of drugs, thus barely providing a chance for micro-organisms to develop resistance. These immense multiple properties exhibited by MeO-NPs will have an impact on the treatment of deadly infectious diseases. This review discusses the mechanisms of action of MeO-NPs against micro-organisms, safety concerns, challenges and future perspectives. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Evaluation of antimicrobial activity of the fruitrind of Picralima nitida ...

African Journals Online (AJOL)

... Proteus mirabilis for the (M) extract of PN. These results provide a rationalization for the traditional use of both plants for the treatment of infections diseases. Keywords: Antimicrobial activity, Cylicodiscus gabunensis, Picralima nitida. West African Journal of Pharmacology and Drug Research Vol. 21 (1&2) 2005: pp. 6-12 ...

Prevalence of resistance to 11 antimicrobials among Campylobacter coli isolated from pigs on 80 grower-finisher farms in Ontario

OpenAIRE

Varela, Norma P.; Friendship, Robert; Dewey, Cate

2007-01-01

We carried out a cross-sectional study to investigate antimicrobial resistance patterns of Campylobacter coli isolated from Ontario grower-finisher pigs. From January to June 2004, 1200 samples were collected from 80 farms by obtaining a constant number (15) of fecal samples per farm. Susceptibility of the isolates to 11 antimicrobial drugs was determined by the agar-dilution technique. The overall prevalence of resistance to 1 or more antimicrobials among the isolates was 99.2%. High levels ...

Thusin, a novel two-component lantibiotic with potent antimicrobial activity against several Gram-positive pathogens

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Bingyue Xin

2016-07-01

Full Text Available Due to the rapidly increasing prevalence of multidrug-resistant bacterial strains, the need for new antimicrobial drugs to treat infections has become urgent. Bacteriocins, which are antimicrobial peptides of bacterial origin, are considered potential alternatives to conventional antibiotics and have attracted widespread attention in recent years. Among these bacteriocins, lantibiotics, especially two-component lantibiotics, exhibit potent antimicrobial activity against some clinically relevant Gram-positive pathogens and have potential applications in the pharmaceutical industry. In this study, we characterized a novel two-component lantibiotic termed thusin that consists of Thsα, Thsβ and Thsβ' (mutation of Thsβ, A14G and that was isolated from a B. thuringiensis strain BGSC 4BT1. Thsα and Thsβ (or Thsβ' exhibit optimal antimicrobial activity at a 1:1 ratio and act sequentially to affect target cells, and they are all highly thermostable (100°C for 30 min and pH tolerant (pH 2.0 to 9.0. Thusin shows remarkable efficacy against all tested Gram-positive bacteria and greater activities than two known lantibiotics thuricin 4A-4 and ticin A4, and one antibiotic vancomycin against various bacterial pathogens (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus (MRSA, Staphylococcus sciuri, Enterococcus faecalis, and Streptococcus pneumoniae. Moreover, thusin is also able to inhibit the outgrowth of Bacillus cereus spores. The potent antimicrobial activity of thusin against some Gram-positive pathogens indicates that it has potential for the development of new drugs.

Emerging Resistance, New Antimicrobial Agents  …  but No Tests! The Challenge of Antimicrobial Susceptibility Testing in the Current US Regulatory Landscape.

Science.gov (United States)

Humphries, R M; Hindler, J A

2016-07-01

Accurate and timely performance of antimicrobial susceptibility testing (AST) by the clinical laboratory is paramount to combating antimicrobial resistance. The ability of laboratories in the United States to effectively perform ASTs is challenged by several factors. Some, such as new resistance mechanisms and the associated evolution of testing recommendations and breakpoints, are inevitable. Others are entirely man-made. These include unnecessarily strict US Food and Drug Administration (FDA) limitations on how commercial AST systems can be used for diagnostic testing, the absence of up-to-date performance data on these systems, and the lack of commercially available FDA-cleared tests for newer antimicrobial agents or for older agents with updated breakpoints. This viewpoint will highlight contemporary AST challenges faced by the clinical laboratory, and propose some solutions. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Exploring Post-Treatment Reversion of Antimicrobial Resistance in Enteric Bacteria of Food Animals as a Resistance Mitigation Strategy.

Science.gov (United States)

Volkova, Victoriya V; KuKanich, Butch; Riviere, Jim E

2016-11-01

Antimicrobial drug use in food animals is associated with an elevation in relative abundance of bacteria resistant to the drug among the animal enteric bacteria. Some of these bacteria are potential foodborne pathogens. Evidence suggests that at least in the enteric nontype-specific Escherichia coli, after treatment the resistance abundance reverts to the background pre-treatment levels, without further interventions. We hypothesize that it is possible to define the distribution of the time period after treatment within which resistance to the administered drug, and possibly other drugs in case of coselection, in fecal bacteria of the treated animals returns to the background pre-treatment levels. Furthermore, it is possible that a novel resistance mitigation strategy for microbiological food safety could be developed based on this resistance reversion phenomenon. The strategy would be conceptually similar to existing antimicrobial drug withdrawal periods, which is a well-established and accepted mitigation strategy for avoiding violative drug residues in the edible products from the treated animals. For developing resistance-relevant withdrawals, a mathematical framework can be used to join the necessary pharmacological, microbiological, and animal production components to project the distributions of the post-treatment resistance reversion periods in the production animal populations for major antimicrobial drug classes in use. The framework can also help guide design of empirical studies into the resistance-relevant withdrawal periods and development of mitigation approaches to reduce the treatment-associated elevation of resistance in animal enteric bacteria. We outline this framework, schematically and through exemplar equations, and how its components could be formulated.

Antimicrobial and antibiofilm potential of biosurfactants isolated from lactobacilli against multi-drug-resistant pathogens

Science.gov (United States)

2014-01-01

Background Biosurfactants (BS) are amphiphilic compounds produced by microbes, either on the cell surface or secreted extracellularly. BS exhibit strong antimicrobial and anti-adhesive properties, making them good candidates for applications used to combat infections. In this study, our goal was to assess the in vitro antimicrobial, anti-adhesive and anti-biofilm abilities of BS produced by Lactobacillus jensenii and Lactobacillus rhamnosus against clinical Multidrug Resistant (MDR) strains of Acinetobacter baumannii, Escherichia coli, and Staphylococcus aureus (MRSA). Cell-bound BS from both L. jensenii and L. rhamnosus were extracted and isolated. The surface activities of crude BS samples were evaluated using an oil spreading assay. The antimicrobial, anti-adhesive and anti-biofilm activities of both BS against the above mentioned MDR pathogens were determined. Results Surface activities for both BS ranged from 6.25 to 25 mg/ml with clear zones observed between 7 and 11 cm. BS of both L. jensenii and L. rhamnosus showed antimicrobial activities against A. baumannii, E. coli and S. aureus at 25-50 mg/ml. Anti-adhesive and anti-biofilm activities were also observed for the aforementioned pathogens between 25 and 50 mg/ml. Finally, analysis by electron microscope indicated that the BS caused membrane damage for A. baumannii and pronounced cell wall damage in S. aureus. Conclusion Our results indicate that BS isolated from two Lactobacilli strains has antibacterial properties against MDR strains of A. baumannii, E. coli and MRSA. Both BS also displayed anti-adhesive and anti-biofilm abilities against A. baumannii, E. coli and S. aureus. Together, these capabilities may open up possibilities for BS as an alternative therapeutic approach for the prevention and/or treatment of hospital-acquired infections. PMID:25124936

Antimicrobial susceptibility patterns of Brazilian Haemophilus parasuis field isolates

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Michela Miani

Full Text Available ABSTRACT: Haemophilus parasuis is the etiological agent of Glässer’s disease (GD, an ubiquitous infection of swine characterized by systemic fibrinous polyserositis, polyarthritis and meningitis. Intensive use of antimicrobial agents in swine husbandries during the last years triggered the development of antibiotic resistances in bacterial pathogens. Thus, regular susceptibility testing is crucial to ensure efficacy of different antimicrobial agents to this porcine pathogen. In this study, 50 clinical isolates from South Brazilian pig herds were characterized and analyzed for their susceptibility to commonly used antibiotic. The identification and typing of clinical isolates was carried out by a modified indirect hemagglutination assay combined with a multiplex PCR. The susceptibility of each isolate was analyzed by broth microdilution method against a panel of 21 antimicrobial compounds. We found that field isolates are highly resistance to gentamycin, bacitracin, lincomycin and tiamulin, but sensitive to ampicillin, clindamycin, neomycin, penicillin, danofloxacin and enrofloxacin. Furthermore, an individual susceptibility analysis indicated that enrofloxacin is effective to treat clinical isolates with the exception of those classified as serovar 1. The results presented here firstly demonstrate the susceptibility of Brazilian clinical isolates of H. parasuis to antimicrobials widely used by swine veterinary practitioners and strengthen the need to perform susceptibility test prior to antibiotic therapy during GD outbreaks. In addition, because only six antimicrobial drugs (28.6% were found effective against field isolates, a continuous surveillance of the susceptibility profile should be of major concern to the swine industry.

Heavy metals in liquid pig manure in light of bacterial antimicrobial resistance

Energy Technology Data Exchange (ETDEWEB)

Hoelzel, Christina S., E-mail: Christina.Hoelzel@wzw.tum.de [Chair of Animal Hygiene, Technische Universitaet Muenchen, Weihenstephaner Berg 3, 85354 Freising (Germany); Mueller, Christa [Institute for Agroecology, Organic Farming and Soil Protection, Bavarian State Research Center for Agriculture (LfL), Lange Point 12, 85354 Freising (Germany); Harms, Katrin S. [Chair of Animal Hygiene, Technische Universitaet Muenchen, Weihenstephaner Berg 3, 85354 Freising (Germany); Mikolajewski, Sabine [Department for Quality Assurance and Analytics, Bavarian State Research Center for Agriculture (LfL), Lange Point 4, 85354 Freising (Germany); Schaefer, Stefanie; Schwaiger, Karin; Bauer, Johann [Chair of Animal Hygiene, Technische Universitaet Muenchen, Weihenstephaner Berg 3, 85354 Freising (Germany)

2012-02-15

Heavy metals are regularly found in liquid pig manure, and might interact with bacterial antimicrobial resistance. Concentrations of heavy metals were determined by atomic spectroscopic methods in 305 pig manure samples and were connected to the phenotypic resistance of Escherichia coli (n=613) against 29 antimicrobial drugs. Concentrations of heavy metals (/kg dry matter) were 0.08-5.30 mg cadmium, 1.1-32.0 mg chrome, 22.4-3387.6 mg copper, <2.0-26.7 mg lead, <0.01-0.11 mg mercury, 3.1-97.3 mg nickel and 93.0-8239.0 mg zinc. Associated with the detection of copper and zinc, resistance rates against {beta}-lactams were significantly elevated. By contrast, the presence of mercury was significantly associated with low antimicrobial resistance rates of Escherichia coli against {beta}-lactams, aminoglycosides and other antibiotics. Effects of subinhibitory concentrations of mercury on bacterial resistance against penicillins, cephalosporins, aminoglycosides and doxycycline were also demonstrated in a laboratory trial. Antimicrobial resistance in the porcine microflora might be increased by copper and zinc. By contrast, the occurrence of mercury in the environment might, due to co-toxicity, act counter-selective against antimicrobial resistant strains.

Antimicrobial susceptibilities of Listeria monocytogenes human strains isolated from 1970 to 2008 in Brazil

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Cristhiane Moura Falavina dos Reis

2011-04-01

Full Text Available INTRODUCTION: Listeria monocytogenes is the causative agent of listeriosis, a foodborne illness that affects mainly pregnant women, the elderly and immunocompromised patients. The primary treatment is a combination of ampicillin with an aminoglycoside, in addition to a second-choice drug represented by chloramphenicol, erythromycin, tetracycline and rifampicin. The aim of this study was to analyze the antimicrobial susceptibility profile of strains isolated from human sources in the last four decades. METHODS: Sixty-eight strains were selected from the culture collection of the Laboratory of Bacterial Zoonoses/LABZOO/FIOCRUZ isolated in different regions of Brazil from 1970 to 2008 and primarily isolated from cerebrospinal fluid and blood culture. Susceptibility tests to antimicrobials drugs were evaluated using the criteria established by Soussy using the Kirby-Bauer method and E-Test strips were used to determine the minimum inhibitory concentration (MIC. RESULTS: Among the strains tested, serovar L4b (60.3% was the most prevalent, followed by serovar 1/2a (20.6%, 1/2b (13.2% and the more uncommon serovars 1/2c, 3b and 4ab (5.9%. All strains were susceptible to ampicillin, cephalothin, erythromycin, gentamicin, teicoplanin and vancomycin. Only one strain (1.5% showed resistance to rifampin, and two (3% were resistant to trimethoprim-sulfamethoxazole. MICs with values up to 2μg/ml reinforce the need for microbiological surveillance. CONCLUSIONS: The study demonstrated low prevalence of strains resistant to the antimicrobial drugs indicated in the treatment of human listeriosis. Monitoring antimicrobial resistance profile is still very important to determine adequate treatment, especially in immunocompromised patients.

Nanoparticles as Antituberculosis Drugs Carriers: Effect on Activity Against Mycobacterium tuberculosis in Human Monocyte-Derived Macrophages

International Nuclear Information System (INIS)

Anisimova, Y.V.; Gelperina, S.I.; Peloquin, C.A.; Heifets, L.B.

2000-01-01

This is the first report evaluating the nanoparticle delivery system for three antituberculosis drugs: isoniazid, rifampin, and streptomycin. The typical particle size is 250 nm. We studied accumulation of these drugs in human monocytes as well as their antimicrobial activity against Mycobacterium tuberculosis residing in human monocyte-derived macrophages. Nanoparticle encapsulation increased the intracellular accumulation (cell-association) of all three tested drugs, but it enhanced the antimicrobial activity of isoniazid and streptomycin only. On the other hand, the activity of encapsulated rifampin against intracellular bacteria was not higher than that of the free drug

A fabric phase sorptive extraction-High performance liquid chromatography-Photo diode array detection method for the determination of twelve azole antimicrobial drug residues in human plasma and urine.

Science.gov (United States)

Locatelli, Marcello; Kabir, Abuzar; Innosa, Denise; Lopatriello, Teresa; Furton, Kenneth G

2017-01-01

This paper reports a novel fabric phase sorptive extraction-high performance liquid chromatography-photodiode array detection (FPSE-HPLC-PDA) method for the simultaneous extraction and analysis of twelve azole antimicrobial drug residues that include ketoconazole, terconazole, voriconazole, bifonazole, clotrimazole, tioconazole, econazole, butoconazole, miconazole, posaconazole, ravuconazole, and itraconazole in human plasma and urine samples. The selected azole antimicrobial drugs were well resolved by using a Luna C 18 column (250mm×4.6mm; 5μm particle size) in gradient elution mode within 36min. The analytical method was calibrated and validated in the range from 0.1 to 8μg/mL for all the drug compounds. Blank human plasma and urine were used as the sample matrix for the analysis; while benzyl-4-hydroxybenzoate was used as the internal standard (IS). The limit of quantification of the FPSE-HPLC-PDA method was found as 0.1μg/mL and the weighted-matrix matched standard calibration curves of the drugs showed a good linearity upto a concentration of 8μg/mL. The parallelism tests were also performed to evaluate whether overrange sample can be analyzed after dilution, without compromising the analytical performances of the validated method. The intra- and inter-day precision (RSD%) values were found ≤13.1% and ≤13.9%, respectively. The intra- and inter-day trueness (bias%) values were found in the range from -12.1% to 10.5%. The performances of the validated FPSE-HPLC-PDA were further tested on real samples collected from healthy volunteers after a single dose administration of itraconazole and miconazole. To the best of our knowledge, this is the first FPSE extraction procedure applied on plasma and urine samples for the simultaneous determination of twelve azole drugs possessing a wide range of logK ow values (extending from 0.4 for fluconazole to 6.70 of butoconazole) and could be adopted as a rapid and robust green analytical tool for clinical and

The Spider Venom Peptide Lycosin-II Has Potent Antimicrobial Activity against Clinically Isolated Bacteria

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Yongjun Wang

2016-04-01

Full Text Available Antimicrobial peptides have been accepted as excellent candidates for developing novel antibiotics against drug-resistant bacteria. Recent studies indicate that spider venoms are the source for the identification of novel antimicrobial peptides. In the present study, we isolated and characterized an antibacterial peptide named lycosin-II from the venom of the spider Lycosa singoriensis. It contains 21 amino acid residue lacking cysteine residues and forms a typical linear amphipathic and cationic α-helical conformation. Lycosin-II displays potent bacteriostatic effect on the tested drug-resistant bacterial strains isolated from hospital patients, including multidrug-resistant A. baumannii, which has presented a huge challenge for the infection therapy. The inhibitory ability of lycosin-II might derive from its binding to cell membrane, because Mg2+ could compete with the binding sites to reduce the bacteriostatic potency of lycosin-II. Our data suggest that lycosin-II might be a lead in the development of novel antibiotics for curing drug-resistant bacterial infections.

Synthesis and Antimicrobial Studies of New Series of Pyrazoline Bearing Bis-Heterocycles via 1,3-Dipolar Cycloaddition Reactions

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B. Jayashankara

2008-01-01

Full Text Available Biologically interesting bis-heterocycles bearing pyrazoline and imidazole moieties have been synthesized. 1H NMR, 13C NMR, IR and elemental analyses characterized the newly synthesized compounds. All the synthesized compounds were evaluated for their antimicrobial activity and were compared with the standard drugs. All the compounds demonstrated potent to weak antimicrobial activity.

Different patterns of inappropriate antimicrobial use in surgical and medical units at a tertiary care hospital in Switzerland: a prevalence survey.

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Alexia Cusini

Full Text Available BACKGROUND: Unnecessary or inappropriate use of antimicrobials is associated with the emergence of antimicrobial resistance, drug toxicity, increased morbidity and health care costs. Antimicrobial use has been reported to be incorrect or not indicated in 9-64% of inpatients. We studied the quality of antimicrobial therapy and prophylaxis in hospitalized patients at a tertiary care hospital to plan interventions to improve the quality of antimicrobial prescription. METHODOLOGY/PRINCIPAL FINDINGS: Experienced infectious diseases (ID fellows performed audits of antimicrobial use at regular intervals among all patients--with or without antimicrobials--hospitalized in predefined surgical, medical, haemato-oncological, or intensive care units. Data were collected from medical and nursing patient charts with a standardized questionnaire. Appropriateness of antimicrobial use was evaluated using a modified algorithm developed by Gyssens et al.; the assessment was double-checked by a senior ID specialist. We evaluated 1577 patients of whom 700 (44.4% had antimicrobials, receiving a total of 1270 prescriptions. 958 (75.4% prescriptions were for therapy and 312 (24.6% for prophylaxis. 37.0% of therapeutic and 16.6% of prophylactic prescriptions were found to be inappropriate. Most frequent characteristics of inappropriate treatments included: No indication (17.5%; incorrect choice of antimicrobials (7.6%; incorrect application of drugs (9.3%; and divergence from institutional guidelines (8%. Characteristics of inappropriate prophylaxes were: No indication (9%; incorrect choice of antimicrobials (1%; duration too long or other inappropriate use (6.7%. Patterns of inappropriate antimicrobial varied widely in the different hospital units; empirical prescriptions were more frequently incorrect than prescriptions based on available microbiological results. CONCLUSIONS/SIGNIFICANCE: Audits of individual patient care provide important data to identify local

Antimicrobial Peptides: a promising class of antimicrobial compounds against BWA and multi-drug resistant bacteria: in the spotlight: the lactoferrin chimera

NARCIS (Netherlands)

Bikker, F.J.; Sijbrandij, T.; Nazmi, K.; Bolscher, J.G.M.; Veerman, E.C.I.; Jansen, H-J.

2014-01-01

Anti-Microbial Peptides (AMPs) are part of the innate immune defense system and considered as promising lead compounds for the development of novel anti-bacterial agents. In general, AMPs are simple, short peptides with broad-spectrum activity against Gram-negative and Gram-positive bacteria, fungi,

Isolation and characterization of pigmented bacteria showing antimicrobial activity from Malaysian marine environment

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Ahmad, A.

2013-01-01

Full Text Available Aims: Natural products play a prominent role in the discovery of leads for the development of drugs in the treatment ofhuman diseases. Much of nature remains to be explored, especially marine and microbial environments.Methodology and results: Fifty-five pigmented marine bacteria were isolated from sponges, seawater, mangrovesediment, sea cucumber and mussel from different coastal area of Malaysia. The antimicrobial activities of thesebacteria were investigated by disk diffusion method against pathogenic bacteria. Out of 55 isolates, 18 isolates exhibitedantimicrobial activity, which based on morphological characterization, 53% of them were Gram positive and 47% wereGram negative. All active isolates were able to tolerate more than 4% NaCl in the nutrient agar medium that indicatedthey were autochthonous to marine environment and moderate salt tolerant in nature. Molecular identification of isolatesby the strong antimicrobial activities indicates that isolates WPRA3 (JX020764 and SM11-3j belong to genus Serratiaand isolate SDPM1 (JQ083392 belongs to genus Zooshikella.Conclusion, significance and impact of study: The results of present study revealed that the active isolates arepotential producer of antimicrobial secondary metabolites and might be utilized as drug candidate.

Polymyxins: Antimicrobial susceptibility concerns and therapeutic options

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V Balaji

2011-01-01

Full Text Available The increasing prevalence of multidrug-resistant nosocomial pathogens such as Acinetobacter baumannii, Pseudomonas aeruginosa and Klebsiella pneumoniae poses a great challenge to the treating physicians. The paucity of newer effective antimicrobials has led to renewed interest in the polymyxin group of drugs, as a last resort for treatment of gram-negative bacterial infections. There is a dearth of information on the pharmacological properties of colistin, leading to difficulties in selecting the right dose, dosing interval, and route of administration for treatment, especially in critically-ill patients. The increasing use of colistin over the last few years necessitates the need for accurate and reliable in vitro susceptibility testing methods. Development of heteroresistant strains as a result of colistin monotherapy is also a growing concern. There is a compelling need from the clinicians to provide options for probable and possible colistin combination therapy for multidrug-resistant bacterial infections in the ICU setting. Newer combination drug synergy determination tests are being developed and reported. There are no standardized recommendations from antimicrobial susceptibility testing reference agencies for the testing and interpretation of these drug combinations. Comparison and analysis of these reported methodologies may help to understand and assist the microbiologist to choose the best method that produces accurate results at the earliest. This will help clinicians to select the appropriate combination therapy. In this era of multidrug resistance it is important for the microbiology laboratory to be prepared, by default, to provide timely synergistic susceptibility results in addition to routine susceptibility, if warranted. Not as a favour or at request, but as a responsibility.

Synergistic Efficacy of Aedes aegypti Antimicrobial Peptide Cecropin A2 and Tetracycline against Pseudomonas aeruginosa

OpenAIRE

Zheng, Zhaojun; Tharmalingam, Nagendran; Liu, Qingzhong; Jayamani, Elamparithi; Kim, Wooseong; Fuchs, Beth Burgwyn; Zhang, Rijun; Vilcinskas, Andreas; Mylonakis, Eleftherios

2017-01-01

The increasing prevalence of antibiotic resistance has created an urgent need for alternative drugs with new mechanisms of action. Antimicrobial peptides (AMPs) are promising candidates that could address the spread of multidrug-resistant bacteria, either alone or in combination with conventional antibiotics. We studied the antimicrobial efficacy and bactericidal mechanism of cecropin A2, a 36-residue α-helical cationic peptide derived from Aedes aegypti cecropin A, focusing on the common pat...

Antimicrobial nature and use of some medicinal plants in Nigeria

African Journals Online (AJOL)

SERVER

2008-03-04

Mar 4, 2008 ... Forty eight medicinal plants in Nigeria were screened for their antimicrobial ... are capable of producing toxic materials, which may exert some ... is commonly used as a means of evaluating drugs or .... zones of growth inhibition and the diameter of these zones were ..... region of Eastern Ghat, S India. Sci.

Diagnostic Accuracy of Global Pharma Health Fund Minilab™ in Assessing Pharmacopoeial Quality of Antimicrobials.

Science.gov (United States)

Pan, Hui; Ba-Thein, William

2018-01-01

Global Pharma Health Fund (GPHF) Minilab™, a semi-quantitative thin-layer chromatography (TLC)-based commercially available test kit, is widely used in drug quality surveillance globally, but its diagnostic accuracy is unclear. We investigated the diagnostic accuracy of Minilab system for antimicrobials, using high-performance liquid chromatography (HPLC) as reference standard. Following the Minilab protocols and the Pharmacopoeia of the People's Republic of China protocols, Minilab-TLC and HPLC were used to test five common antimicrobials (506 batches) for relative concentration of active pharmaceutical ingredients. The prevalence of poor-quality antimicrobials determined, respectively, by Minilab TLC and HPLC was amoxicillin (0% versus 14.9%), azithromycin (0% versus 17.4%), cefuroxime axetil (14.3% versus 0%), levofloxacin (0% versus 3.0%), and metronidazole (0% versus 38.0%). The Minilab TLC had false-positive and false-negative detection rates of 2.6% (13/506) and 15.2% (77/506) accordingly, resulting in the following test characteristics: sensitivity 0%, specificity 97.0%, positive predictive value 0, negative predictive value 0.8, positive likelihood ratio 0, negative likelihood ratio 1.0, diagnostic odds ratio 0, and adjusted diagnostic odds ratio 0.2. This study demonstrates unsatisfying diagnostic accuracy of Minilab system in screening poor-quality antimicrobials of common use. Using Minilab as a stand-alone system for monitoring drug quality should be reconsidered.

Identification and antimicrobial resistance of microflora colonizing feral pig (Sus scrofa of Brazilian Pantanal

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SS Lessa

2011-06-01

Full Text Available Antimicrobial resistance of bacteria is a worldwide problem affecting wild life by living with resistant bacteria in the environment. This study presents a discussion of outside factors environment on microflora of feral pigs (Sus scrofa from Brazilian Pantanal. Animals had samples collected from six different body sites coming from two separated geographic areas, Nhecolandia and Rio Negro regions. With routine biochemical tests and commercial kits 516 bacteria were identified, with 240 Gram-positive, predominantly staphylococci (36 and enterococci (186 strains. Among Gram-negative (GN bacteria the predominant specimens of Enterobacteriaceae (247 mainly represented by Serratia spp. (105, Escherichia coli (50, and Enterobacter spp. (40 and specimens not identified (7. Antimicrobial susceptibility was tested against 17 drugs by agar diffusion method. Staphylococci were negative to production of enterotoxins and TSST-1, with all strains sensitive towards four drugs and highest resistance toward ampicillin (17%. Enterococci presented the highest sensitivity against vancomycin (98%, ampicillin (94% and tetracycline (90%, and highest resistance pattern toward oxacillin (99%, clindamycin (83%, and cotrimoxazole (54%. In GN the highest resistance was observed with Serratia marcescens against CFL (98%, AMC (66% and AMP (60% and all drugs was most effective against E. coli SUT, TET (100%, AMP, TOB (98%, GEN, CLO (95%, CFO, CIP (93%. The results show a new profile of oxacillin-resistant enterococci from Brazilian feral pigs and suggest a limited residue and spreading of antimicrobials in the environment, possibly because of low anthropogenic impact reflected by the drug susceptibility profile of bacteria isolated.

Natural Cinnamic Acids, Synthetic Derivatives and Hybrids with Antimicrobial Activity

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Juan David Guzman

2014-11-01

Full Text Available Antimicrobial natural preparations involving cinnamon, storax and propolis have been long used topically for treating infections. Cinnamic acids and related molecules are partly responsible for the therapeutic effects observed in these preparations. Most of the cinnamic acids, their esters, amides, aldehydes and alcohols, show significant growth inhibition against one or several bacterial and fungal species. Of particular interest is the potent antitubercular activity observed for some of these cinnamic derivatives, which may be amenable as future drugs for treating tuberculosis. This review intends to summarize the literature data on the antimicrobial activity of the natural cinnamic acids and related derivatives. In addition, selected hybrids between cinnamic acids and biologically active scaffolds with antimicrobial activity were also included. A comprehensive literature search was performed collating the minimum inhibitory concentration (MIC of each cinnamic acid or derivative against the reported microorganisms. The MIC data allows the relative comparison between series of molecules and the derivation of structure-activity relationships.

Quality Assessment of the Commonly Prescribed Antimicrobial Drug ...

African Journals Online (AJOL)

have an effective means of monitoring the quality of generic drug products in the market. This results in widespread ... countries. Marketing of such drugs has been widely reported in Africa, Asia, and Latin America. © CNCS .... three-fourth of the plate. The plate was dried in air for 15 minutes and examined under UV-light,.

Synthesis of New Macrocyclic Polyamides as Antimicrobial Agent Candidates

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Osama I. Abd El-Salam

2012-12-01

Full Text Available A series of macrocyclic imides and Schiff-bases have been prepared via the cyclocondensation of pyridine-2,6-dicarbonyl dichloride (1 with L-ornithine methyl ester to give the corresponding macrocyclic bisester 2. Treatment of 2 with hydrazine hydrate gave macrocyclic bisacid hydrazide 3, which was used as starting material. Condensation of bishydrazide 3 with diacid anhydrides or aromatic aldehydes in refluxing acetic acid or ethanol gave the corresponding macrocyclic bisimides 4, 5a,b and macrocyclic bis- hydrazones 6a–j, respectively. The structure assignments of the new compounds were based on chemical and spectroscopic evidence. The antimicrobial screening showed that many of these newly synthesized compounds have good antimicrobial activities, comparable to ampicillin and ketaconazole used as reference drugs.

Antimicrobial and biocompatible properties of nanomaterials.

Science.gov (United States)

Ul-Islam, M; Shehzad, A; Khan, S; Khattak, W A; Ullah, M W; Park, J K

2014-01-01

The rapid development of drug-resistant characteristics in pathogenic viral, bacterial, and fungal species and the consequent spread of infectious diseases are currently receiving serious attention. Indeed, there is a pressing demand to explore novel materials and develop new strategies that can address these issues of serious concern. Nanomaterials are currently proving to be the most capable therapeutic agents to cope with such hazards. The exceptional physiochemical properties and impressive antimicrobial capabilities of nanoparticles have provoked their utilization in biomedical fields. Nanomaterials of both organic and inorganic nature have shown the capabilities of disrupting microbial cells through different mechanisms. Along with the direct influence on the microbial cell membrane, DNA and proteins, these nanomaterials produce reactive oxygen species (ROS) that damage cell components and viruses. Currently, a serious hazard associated with these antimicrobial nanomaterials is their toxicity to human and animal cells. Extensive studies have reported the dose, time, and cell-dependent toxicology of various nanomaterials, and some have shown excellent biocompatible properties. Nevertheless, there is still debate regarding the use of nanomaterials for medical applications. Therefore, in this review, the antimicrobial activities of various nanomaterials with details of their acting mechanisms were compiled. The relative toxic and biocompatible behavior of nanomaterials emphasized in this study provides information pertaining to their practical applicability in medical fields.

Antimicrobial-Induced Cytopenia and Bone Marrow Hypocellularity in Patients with Cirrhosis

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Anupama Patil

2018-01-01

Full Text Available There is great variation in cytopenias in cirrhotic patients with same severity and hypersplenism and their causative factors are not clear. Recent studies have highlighted the role of gut microbiome in regulation of constant and emergency hematopoiesis. Broad-spectrum antibiotics can disrupt the homeostatic or adaptive microbiota in cirrhosis, leading to impaired hematopoiesis and a higher susceptibility to infections. We studied all patients with cirrhosis with cytopenia (anemia, leucopenia, and/or thrombocytopenia, admitted in the Institute of Liver & Biliary Sciences, between January 2016 and July 2017, who underwent a bone marrow examination. The effect of the different antimicrobial agents on peripheral blood counts and bone marrow cellularity was assessed. A total of 196 patients’ data was analyzed for this study. Patients on antimicrobials (n=115 had significantly lower hemoglobin (p<0.001, total leucocyte count (p=0.048, and platelet count (p=0.043 compared to patients not on antimicrobials. On unadjusted analysis, significant association with thrombocytopenia existed in beta-lactams (OR = 1.56, 95% CI = 1.06–2.40, quinolones (OR = 1.66, 95% CI = 1.11–2.61, and antifungals (OR = 2.24, 95% CI = 1.96–4.34. Cephalosporins were found to be significantly associated with anemia (OR = 1.91, 95% CI = 1.07–3.41. Patients who received antimicrobials had hypocellular marrow (p<0.001 as compared to nonrecipients of antibiotics. The adjusted analysis showed that quinolones and beta-lactam antibiotics are the drug classes having significant association with thrombocytopenia and alternative class of drug should be explored in these patients to avoid severe thrombocytopenia.

Nanostructured mesoporous silica: new perspectives for fighting antimicrobial resistance

International Nuclear Information System (INIS)

Voicu, Georgeta; Dogaru, Ionuţ; Meliţă, Daniela; Meştercă, Raluca; Spirescu, Vera; Stan, Eliza; Tote, Eliza; Mogoantă, Laurenţiu; Mogoşanu, George Dan; Grumezescu, Alexandru Mihai; Truşcă, Roxana; Vasile, Eugeniu; Iordache, Florin; Chifiriuc, Mariana-Carmen; Holban, Alina Maria

2015-01-01

This paper investigates the antimicrobial potential of nanostructured mesoporous silica (NMS) functionalized with essential oils (EOs) and antibiotics (ATBs). The NMS networks were obtained by the basic procedure from cetyltrimethylammonium bromide and tetraethyl orthosilicate in the form of granules with diameters ranging from 100 to 300 nm with an average pore diameter of 2.2 nm, as confirmed by the BET–TEM analyses. The Salvia officinalis (SO) and Coriandrum sativum (CS) EOs and the streptomycin and neomycin ATBs were loaded in the NMS pores. TG analysis was performed in order to estimate the amount of the entrapped volatile EOs. The results of the biological analyses revealed that NMS/SO and NMS/CS exhibited a very good antimicrobial activity to an extent comparable or even superior to the one triggered by ATB, and a good in vitro and in vivo biocompatibility. Due to their regular pores, high biocompatibility, antimicrobial activity, and capacity to stabilize the volatile EOs, the obtained NMS can be used as an efficient drug delivery system for further biomedical applications

Nanostructured mesoporous silica: new perspectives for fighting antimicrobial resistance

Energy Technology Data Exchange (ETDEWEB)

Voicu, Georgeta; Dogaru, Ionuţ; Meliţă, Daniela; Meştercă, Raluca; Spirescu, Vera; Stan, Eliza; Tote, Eliza [Politehnica University of Bucharest, Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science (Romania); Mogoantă, Laurenţiu [University of Medicine and Pharmacy of Craiova, Research Center for Microscopic Morphology and Immunology (Romania); Mogoşanu, George Dan [University of Medicine and Pharmacy of Craiova, Department of Pharmacognosy & Phytotherapy, Faculty of Pharmacy (Romania); Grumezescu, Alexandru Mihai, E-mail: grumezescu@yahoo.com [Politehnica University of Bucharest, Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science (Romania); Truşcă, Roxana [Metav SA-CD S.A. (Romania); Vasile, Eugeniu [Politehnica University of Bucharest, Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science (Romania); Iordache, Florin [Institute of Cellular Biology and Pathology of Romanian Academy, “Nicolae Simionescu”, Department of Fetal and Adult Stem Cell Therapy (Romania); Chifiriuc, Mariana-Carmen [University of Bucharest, Microbiology Department, Faculty of Biology (Romania); Holban, Alina Maria [Politehnica University of Bucharest, Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science (Romania)

2015-05-15

This paper investigates the antimicrobial potential of nanostructured mesoporous silica (NMS) functionalized with essential oils (EOs) and antibiotics (ATBs). The NMS networks were obtained by the basic procedure from cetyltrimethylammonium bromide and tetraethyl orthosilicate in the form of granules with diameters ranging from 100 to 300 nm with an average pore diameter of 2.2 nm, as confirmed by the BET–TEM analyses. The Salvia officinalis (SO) and Coriandrum sativum (CS) EOs and the streptomycin and neomycin ATBs were loaded in the NMS pores. TG analysis was performed in order to estimate the amount of the entrapped volatile EOs. The results of the biological analyses revealed that NMS/SO and NMS/CS exhibited a very good antimicrobial activity to an extent comparable or even superior to the one triggered by ATB, and a good in vitro and in vivo biocompatibility. Due to their regular pores, high biocompatibility, antimicrobial activity, and capacity to stabilize the volatile EOs, the obtained NMS can be used as an efficient drug delivery system for further biomedical applications.

Intrinsic, adaptive and acquired antimicrobial resistance in Gram-negative bacteria.

Science.gov (United States)

Arzanlou, Mohsen; Chai, Wern Chern; Venter, Henrietta

2017-02-28

Gram-negative bacteria are responsible for a large proportion of antimicrobial-resistant infections in humans and animals. Among this class of bacteria are also some of the most successful environmental organisms. Part of this success is their adaptability to a variety of different niches, their intrinsic resistance to antimicrobial drugs and their ability to rapidly acquire resistance mechanisms. These mechanisms of resistance are not exclusive and the interplay of several mechanisms causes high levels of resistance. In this review, we explore the molecular mechanisms underlying resistance in Gram-negative organisms and how these different mechanisms enable them to survive many different stress conditions. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Chemical Composition and Antimicrobial Activities of Iranian Propolis

Science.gov (United States)

Afrouzan, Houshang; Tahghighi, Azar; Zakeri, Sedigheh; Es-haghi, Ali

2018-01-01

Background: With considering the importance of natural products for their remedial and therapeutic value, this research was aimed to analyze the chemical compositions and antimicrobial activity of four propolis samples from different areas of Iran (Chenaran, Taleghan, Morad Beyg, and Kalaleh) with various climates and flora. Methods: Ethanolic (70% EtOH) and dichlromethane (DCM) extracts of Iranian propolis were analyzed by gas chromatography-mass spectrometry (GC-MS) methods, and antimicrobial activity was evaluated against Candida albicans, Escherichia coli, and Staphylococcus aureus using disk diffusion antimicrobial method. Results: The results of GC-MS analysis showed the presence of fatty acids, flavonoids, terpenes, aromatic-aliphatic acids, and their related esters. The total flavonoids in DCM extract of Chenaran, Taleghan, Morad Beyg, and Kalaleh propolis were pinocembrin and pinostrobin chalcone. The common phenolic and terpene compounds detected in all four tested EtOH extracts were P-cumaric acid and dimethyl -1,3,5,6-tetramethyl-[1,3-(13C2)] bicycloce [5.5.0] dodeca-1,3,5,6,8,10-hexaene-9,10-dicarboxylate, respectively. The highest inhibitory diameter zone of the Iranian propolis against C. albicans, E. coli, and S. aureus was for DCM extract of Kalaleh propolis (13.33 mm), Morad Beyg propolis (12 mm), and Kalaleh (11.67 mm), respectively. Conclusion: Iranian propolis showed antimicrobial activities against C. albicans, E. coli, and S. aurous, perhaps due to the presence of flavonoids, phenolic acids, and terpenes as active components that can be used alone or in combination with the selected antibiotics to synergize antibiotic effect, as well as to prevent microbial resistance to available antimicrobial drugs. PMID:28558440

Antimicrobial sensitivity pattern of urine isolates from asymptomatic bacteriuria during pregnancy

International Nuclear Information System (INIS)

Khattak, A.M.; Khan, H.U.; Mashud, I.U.; Ashiq, B.; Shah, S.H.

2006-01-01

Screening women for asymptomatic bacteriuria (ASB) on the first antenatal visit is a part of standard obstetric care. Treating women with ASB decreases the chances of maternal and foetal complications. This study was conducted to find out the spectrum of urine pathogens and their drug susceptibility pattern for ASB during pregnancy. The study was conducted in the Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre Karachi, from September 2001 to March 2002. Two hundred and ninety women, apparently normal with confirmed pregnancy, were registered. A voided midstream urine specimen was collected and cultured. A significant growth i.e. >105 organisms/ml was identified with Analytical Profile Index 20 tests for identification of Enterobacteriaceae (API-20-E) and for Gram positive cocci by other standard methods. The prevalence of ASB was found 6.2%. Antimicrobial sensitivity was determined by disc diffusion Kirby Bauyer method after matching the turbidity with 0.5 McFarland's standard. Most of the recommended drugs were found to have encouraging results, however, Escherichia coli showed 66.67% resistance to ampicillins and sulphonamides. Enterobacters showed 100% resistance to ampicillins, cephalosporins and nitrofurantoin. Staphylococcus saprophyticus showed 66.67% resistance to ampicillins and sulphonamides. It was concluded that detection of ASB during pregnancy and appropriate use of antimicrobials is only possible after culture of urine. Empirical anti-microbial therapy cannot be relied upon because of possible risk of resistance. (author)

Antimicrobial topical agents used in the vagina.

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Frey Tirri, Brigitte

2011-01-01

Vaginally applied antimicrobial agents are widely used in the vagina in women with lower genital tract infections. An 'antimicrobial' is a general term that refers to a group of drugs that are effective against bacteria, fungi, viruses and protozoa. Topical treatments can be prescribed for a wide variety of vaginal infections. Many bacterial infections, such as bacterial vaginosis, desquamative inflammatory vaginitis or, as some European authors call it, aerobic vaginitis as well as infection with Staphylococcus aureus or group A streptococci, may be treated in this way. Candida vulvovaginitis is a fungal infection that is very amenable to topical treatment. The most common viral infections which can be treated with topical medications are condylomata acuminata and herpes simplex. The most often encountered protozoal vaginitis, which is caused by Trichomonas vaginalis, may be susceptible to topical medications, although this infection is treated systemically. This chapter covers the wide variety of commonly used topical antimicrobial agents for these diseases and focuses on the individual therapeutic agents and their clinical efficacy. In addition, potential difficulties that can occur in practice, as well as the usage of these medications in the special setting of pregnancy, are described in this chapter. Copyright © 2011 S. Karger AG, Basel.

Transcriptome Profiling of Antimicrobial Resistance in Pseudomonas aeruginosa

OpenAIRE

Khaledi, Ariane; Schniederjans, Monika; Pohl, Sarah; Rainer, Roman; Bodenhofer, Ulrich; Xia, Boyang; Klawonn, Frank; Bruchmann, Sebastian; Preusse, Matthias; Eckweiler, Denitsa; Dötsch, Andreas; Häussler, Susanne

2016-01-01

Emerging resistance to antimicrobials and the lack of new antibiotic drug candidates underscore the need for optimization of current diagnostics and therapies to diminish the evolution and spread of multidrug resistance. As the antibiotic resistance status of a bacterial pathogen is defined by its genome, resistance profiling by applying next-generation sequencing (NGS) technologies may in the future accomplish pathogen identification, prompt initiation of targeted individualized treatment, a...

Vigilancia del consumo de antimicrobianos en hospitales de México: situación actual y guía práctica para su implementación Surveillance of antimicrobial drug use in Mexican hospitals: current situation and practical guidelines for its implementation

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Odalis Rodríguez-Ganen

2012-11-01

Full Text Available En México se han constatado un elevado consumo de antibióticos, su uso irracional en la atención primaria y altas tasas de resistencia en bacterias causantes de infecciones nosocomiales. Se hace necesario revisar la metodología recomendada para informar el consumo de antimicrobianos, de manera que la cuantificación se realice mediante estudios de utilización de medicamentos. Estos estudios, que permiten conocer los medicamentos utilizados en el hospital, requieren de una fuente de datos de consumo de antimicrobianos accesible y con el menor riesgo de sesgos, un sistema de identificación único para los fármacos y la adopción de unidades de medida extrapolables. Se propone usar la metodología elaborada por el Centro Colaborador de la Organización Mundial de la Salud para la Metodología Estadística de Medicamentos, basada en la clasificación anatómica, terapéutica y química (ATC y la dosis diaria definida (DDD. A pesar de sus limitaciones, el empleo de esta metodología para el monitoreo local del consumo de antimicrobianos permite detectar diferencias en los patrones de uso respecto a otras instituciones y, sobre todo, las tendencias dentro de una misma institución. Esto ayudaría a alertar oportunamente sobre posibles problemas en la utilización de antimicrobianos y la necesidad de implementar intervenciones específicas.Antibiotic use in Mexico is characterized by high levels of consumption, irrational use in primary care services, and high rates of bacterial resistance that cause hospital infections. Changes are needed in the recommended method for reporting antimicrobial drug use, so that quantification can be carried out through drug utilization studies. Such studies, which make it possible to know which drugs are used in hospitals, require an accessible source of data on antimicrobial drug use with the least risk of biases, a single drug identification system, and the adoption of units of measure that can be extrapolated

Government policy interventions to reduce human antimicrobial use: protocol for a systematic review and meta-analysis.

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Rogers Van Katwyk, Susan; Grimshaw, Jeremy M; Mendelson, Marc; Taljaard, Monica; Hoffman, Steven J

2017-12-13

Antimicrobial resistance (AMR) is a recognized threat to global public health. Increasing AMR and a dry pipeline of novel antimicrobial drugs have put AMR in the international spotlight. One strategy to combat AMR is to reduce antimicrobial drug consumption. Governments around the world have been experimenting with different policy interventions, such as regulating where antimicrobials can be sold, restricting the use of last-resort antimicrobials, funding AMR stewardship programs, and launching public awareness campaigns. To inform future action, governments should have access to synthesized data on the effectiveness of large-scale AMR interventions. This planned systematic review will (1) identify and describe previously evaluated government policy interventions to reduce human antimicrobial use and (2) estimate the effectiveness of these different strategies. An electronic search strategy has been developed in consultation with two research librarians. Seven databases (MEDLINE, CINAHL, EMBASE, CENTRAL, PAIS Index, Web of Science, and PubMed excluding MEDLINE) will be searched, and additional studies will be identified using several gray literature search strategies. To be included, a study must (1) clearly describe the government policy and (2) use a rigorous design to quantitatively measure the impact of the policy on human antibiotic use. The intervention of interest is any policy intervention enacted by a government or government agency in any country to change human antimicrobial use. Two independent reviewers will screen for eligibility using criteria defined a priori. Data will be extracted with Covidence software using a customized extraction form. If sufficient data exists, a meta-analysis by intervention type will be conducted as part of the effectiveness review. However, if there are too few studies or if the interventions are too heterogeneous, data will be tabulated and a narrative synthesis strategy will be used. This evidence synthesis is intended

Secular trends in Klebsiella pneumoniae isolated in a tertiary-care hospital: increasing prevalence and accelerated decline in antimicrobial susceptibility

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Rodrigo de Carvalho Santana

2016-04-01

Full Text Available Abstract: INTRODUCTION Klebsiella pneumoniae has become an increasingly important etiologic agent of nosocomial infections in recent years. This is mainly due to the expression of virulence factors and development of resistance to several antimicrobial drugs. METHODS This retrospective study examines data obtained from the microbiology laboratory of a Brazilian tertiary-care hospital. To assess temporal trends in prevalence and antimicrobial susceptibility, K. pneumoniae isolates were analyzed from 2000 to 2013. The relative frequencies of K. pneumoniae isolation were calculated among all Gram-negative bacilli isolated in each period analyzed. Susceptibility tests were performed using automated systems. RESULTS: From 2000-2006, K. pneumonia isolates comprised 10.7% of isolated Gram-negative bacilli (455/4260. From 2007-2013, this percentage was 18.1% (965/5331. Strictly considering isolates from bloodstream infections, the relative annual prevalence of K. pneumoniae increased from 14-17% to 27-32% during the same periods. A progressive decrease in K. pneumoniae susceptibility to all antimicrobial agents assessed was detected. Partial resistance was also observed to antimicrobial drugs that have been used more recently, such as colistin and tigecycline. CONCLUSIONS Our study indicates that K. pneumoniae has become a major pathogen among hospitalized patients and confirms its recent trend of increasing antimicrobial resistance.

Conformational study of melectin and antapin antimicrobial peptides in model membrane environments

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Kocourková, Lucie; Novotná, Pavlína; Čujová, Sabína; Čeřovský, Václav; Urbanová, Marie; Setnička, Vladimír

2017-01-01

Antimicrobial peptides have long been considered as promising compounds against drug-resistant pathogens. In this work, we studied the secondary structure of antimicrobial peptides melectin and antapin using electronic (ECD) and vibrational circular dichroism (VCD) spectroscopies that are sensitive to peptide secondary structures. The results from quantitative ECD spectral evaluation by Dichroweb and CDNN program and from the qualitative evaluation of the VCD spectra were compared. The antimicrobial activity of the selected peptides depends on their ability to adopt an amphipathic α-helical conformation on the surface of the bacterial membrane. Hence, solutions of different zwitterionic and negatively charged liposomes and micelles were used to mimic the eukaryotic and bacterial biological membranes. The results show a significant content of α-helical conformation in the solutions of negatively charged liposomes mimicking the bacterial membrane, thus correlating with the antimicrobial activity of the studied peptides. On the other hand in the solutions of zwitterionic liposomes used as models of the eukaryotic membranes, the fraction of α-helical conformation was lower, which corresponds with their moderate hemolytic activity.

Alternative Antimicrobial Approach: Nano-Antimicrobial Materials

OpenAIRE

Nurit Beyth; Yael Houri-Haddad; Avi Domb; Wahid Khan; Ronen Hazan

2015-01-01

Despite numerous existing potent antibiotics and other antimicrobial means, bacterial infections are still a major cause of morbidity and mortality. Moreover, the need to develop additional bactericidal means has significantly increased due to the growing concern regarding multidrug-resistant bacterial strains and biofilm associated infections. Consequently, attention has been especially devoted to new and emerging nanoparticle-based materials in the field of antimicrobial chemotherapy. The ...

New perspectives for natural antimicrobial peptides: application as antinflammatory drugs in a murine model.

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Capparelli, Rosanna; De Chiara, Francesco; Nocerino, Nunzia; Montella, Rosa Chiara; Iannaccone, Marco; Fulgione, Andrea; Romanelli, Alessandra; Avitabile, Concetta; Blaiotta, Giuseppe; Capuano, Federico

2012-11-17

Antimicrobial peptides (AMPs) are an ancient group of defense molecules. AMPs are widely distributed in nature (being present in mammals, birds, amphibians, insects, plants, and microorganisms). They display bactericidal as well as immunomodulatory properties. The aim of this study was to investigate the antimicrobial and anti-inflammatory activities of a combination of two AMPs (temporin B and the royal jellein I) against Staphylococcus epidermidis. The temporin B (TB-KK) and the royal jelleins I, II, III chemically modified at the C terminal (RJI-C, RJII-C, RJIII-C), were tested for their activity against 10 different Staphylococcus epidermidis strains, alone and in combination. Of the three royal jelleins, RJI-C showed the highest activity. Moreover, the combination of RJI-C and TB-KK (MIX) displayed synergistic activity. In vitro, the MIX displayed low hemolytic activity, no NO2- production and the ability to curb the synthesis of the pro-inflammatory cytokines TNF-α and IFN-γ to the same extent as acetylsalicylic acid. In vivo, the MIX sterilized mice infected with Staphylococcus epidermidis in eleven days and inhibited the expression of genes encoding the prostaglandin-endoperoxide synthase 2 (COX-2) and CD64, two important parameters of inflammation. The study shows that the MIX - a combination of two naturally occurring peptides - displays both antimicrobial and anti-inflammatory activities.

Cell physiology based pharmacodynamic modeling of antimicrobial drug combinations

OpenAIRE

Hethey, Christoph Philipp

2017-01-01

Mathematical models of bacterial growth have been successfully applied to study the relationship between antibiotic drug exposure and the antibacterial effect. Since these models typically lack a representation of cellular processes and cell physiology, the mechanistic integration of drug action is not possible on the cellular level. The cellular mechanisms of drug action, however, are particularly relevant for the prediction, analysis and understanding of interactions between antibiotics. In...

Antimicrobial resistance of bacterial strains isolated from avian cellulitis

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MM Santos

2014-03-01

Full Text Available Avian cellulitis is an inflammatory process in the subcutaneous tissue, mainly located in the abdomen and thighs. This problem is commonly observed in poultry at slaughter and it is considered one of the major causes of condemnation of carcasses in Brazil. The aim of this study was to perform the microbial isolation of lesions of avian cellulitis from a processing plant located in the State of Goiás in order to analyze antimicrobial resistance by antibiogram test and to detect resistance genes by polymerase chain reaction. A total of 25 samples of avian cellulitis lesions were analyzed, from which 30 bacterial strains were isolated. There were eleven (44% strains of Escherichia coli, nine (36% strains of Staphylococcus epidermidis, seven (28% strains of Proteus mirabilis and three (12% strains of Manheimiahaemolytica. The antibiogram test showed that all strains were resistant to at least one antimicrobial. The gene of antimicrobial resistance tetB was detected in E. coli, S. epidermidis and P. mirabilis strains, and was the most frequently observed gene. The gene of antimicrobial resistance Sul1 was detected in all bacterial species, while tetA was found in E. coli and S. epidermidis strains, SHV in E. coli strains, S. epidermidis and P. mirabilis,and cat1 in one P. mirabilis strain. The results suggest a potential public health hazard due to the ability of these microorganisms to transmit antimicrobial resistancegenes to other microorganisms present in the intestinal tract of humans and animals, which may affect clinical-medical usage of these drugs.

N-halamine-based rechargeable antimicrobial and biofilm-controlling polyurethane

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Sun, Xinbo; Cao, Zhengbing; Porteous, Nuala; Sun, Yuyu

2012-01-01

An N-halamine precursor, 5, 5-dimethyl hydantoin (DMH), was covalently linked to the surface of polyurethane (PU) with 1,6-hexamethylene diisocyanate (HDI) as a coupling agent. The reaction pathways were investigated using propyl isocyanate (PI) as a model compound, and the results suggested that the imide and amide groups of DMH had very similar reactivity toward the isocyanate groups on PU surfaces activated with HDI. After bleach treatment, the covalently bound DMH moieties were transformed into N-halamines. The new N-halmaine-based PU provided potent antimicrobial effects against Staphylococcus aureus (S. aureus, Gram-positive), Escherichia coli (E. coli, Gram-negative), methicillin-resistant staphylococcus aureus (MRSA, drug resistant Gram-positive bacteria), vancomycin-resistant enterococcus (VRE, drug resistant Gram-positive bacteria), and Candida albicans (C. ablicans, fungi), and successfully prevented bacterial and fungal biofilm formation. The antimicrobial and biofilm-controlling effects were stable for longer than 6 months under normal storage in open air. Furthermore, if the functions were lost due to prolonged use, they could be recharged by another chlorination treatment. The recharging could be repeated as needed to achieve long-term protection against microbial contamination and biofilm-formation. PMID:22244984

Preparation and properties of a drug sustained-release hydrogel film

International Nuclear Information System (INIS)

Yue Ling; Yang Zhanshan; Yang Shuqin; Li Qinghua

2009-01-01

A hydrogel film of drug sustained-release was prepared to accelerate wound healing. The hydrogel films containing drug or not were prepared by the freezing and thawing process. Their properties such as the physicochemical property and the drug release behavior in vitro were studied. Effect of the freezing and thawing process on antimicrobial efficacy of the gentamicin was evaluated by diffusion method. The results indicate that swelling ratio of the hydrogel films freezed for 4h is 841.21% and their gel fraction, tensile strength and elongation at break is 96.10%, 0.222 MPa and 673.50% respectively. The antimicrobial efficacy of the gentamicin has no change. The hydrogel film contained gentamicin releases the antibiotic to peak during 6 h with the cumulative drug release rate of 59.57%. The drug releases continually up to the 5th day. The drug delivery conforms to Higuchi kinetic equation, and mechanism of the drug release is matrix diffusion. The results show that the hydrogel film prepared by the freezing and thawing process display satisfactory physicochemical properties and can be used as a drug delivery system. (authors)

Clemastine as Antimicrobial Agent: Effectiveness and Mechanism of Action

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S.Fazli Bazaz

1991-07-01

Full Text Available In this investigation, the antimicrobial activity of Clemastine was studied.The Minimum Inhibitory Concentrations (MICs of this drug against some bacteria were determined using tube dilution method.To find out the bactericidal activity of Clemastine, the number of living bacteria in the presence of drug was counted by a culture method (pour plate method. Thereafter, the preservative effectiveness of Clemastine was studied in detail using standard method (USP 1985.The results show a good antibacterial but not antifungal activity."nIn considering the mechanism of action of Clemastine, it can be seen that the drug has some effect on cell membrane permeability and causes leakage of intracellular material including the K+ .Comparing the bactericidal results with the leakage of K+, shows that the leakage may be due to the bactericidal activity of the drug.

Fungi treated with small chemicals exhibit increased antimicrobial activity against facultative bacterial and yeast pathogens.

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Zutz, Christoph; Bandian, Dragana; Neumayer, Bernhard; Speringer, Franz; Gorfer, Markus; Wagner, Martin; Strauss, Joseph; Rychli, Kathrin

2014-01-01

For decades, fungi have been the main source for the discovery of novel antimicrobial drugs. Recent sequencing efforts revealed a still high number of so far unknown "cryptic" secondary metabolites. The production of these metabolites is presumably epigenetically silenced under standard laboratory conditions. In this study, we investigated the effect of six small mass chemicals, of which some are known to act as epigenetic modulators, on the production of antimicrobial compounds in 54 spore forming fungi. The antimicrobial effect of fungal samples was tested against clinically facultative pathogens and multiresistant clinical isolates. In total, 30 samples of treated fungi belonging to six different genera reduced significantly growth of different test organisms compared to the untreated fungal sample (growth log reduction 0.3-4.3). For instance, the pellet of Penicillium restrictum grown in the presence of butyrate revealed significant higher antimicrobial activity against Staphylococcus (S.) aureus and multiresistant S. aureus strains and displayed no cytotoxicity against human cells, thus making it an ideal candidate for antimicrobial compound discovery. Our study shows that every presumable fungus, even well described fungi, has the potential to produce novel antimicrobial compounds and that our approach is capable of rapidly filling the pipeline for yet undiscovered antimicrobial substances.

Costs and length of stay associated with antimicrobial resistance in acute kidney injury patients with bloodstream infection.

Science.gov (United States)

Vandijck, D M; Blot, S I; Decruyenaere, J M; Vanholder, R C; De Waele, J J; Lameire, N H; Claus, S; De Schuijmer, J; Dhondt, A W; Verschraegen, G; Hoste, E A

2008-01-01

Antimicrobial resistance negatively impacts on prognosis. Intensive care unit (ICU) patients, and particularly those with acute kidney injury (AKI), are at high risk for developing nosocomial bloodstream infections (BSI) due to multi-drug-resistant strains. Economic implications in terms of costs and length of stay (LOS) attributable to antimicrobial resistance are underevaluated. This study aimed to assess whether microbial susceptibility patterns affect costs and LOS in a well-defined cohort of ICU patients with AKI undergoing renal replacement therapy (RRT) who developed nosocomial BSI. Historical study (1995-2004) enrolling all adult RRT-dependent ICU patients with AKI and nosocomial BSI. Costs were considered as invoiced in the Belgian reimbursement system, and LOS was used as a surrogate marker for hospital resource allocation. Of the 1330 patients with AKI undergoing RRT, 92 had microbiologic evidence of nosocomial BSI (57/92, 62% due to a multi-drug-resistant microorganism). Main patient characteristics were equal in both groups. As compared to patients with antimicro-4 bial-susceptible BSI, patients with antimicrobial-resistant BSI were more likely to acquire Gram-positive infection (72.6% vs 25.5%, P0.05) or hospital costs (all P>0.05) when comparing patients with antimicrobial-resistant vs antimicrobial-susceptible BSI. However, although not statistically significant, patients with BSI caused by resistant Gram-negative-, Candida-, or anaerobic bacteria incurred substantial higher costs than those without. In a cohort of ICU patients with AKI and nosocomial BSI undergoing RRT, patients with antimicrobial-resistant vs antimicrobial-susceptible Gram-positive BSI did not have longer hospital stays, or higher hospital costs. Patients with resistant "other" (i.e. Gram-negative, Candida, or anaerobic) BSI were found to have a distinct trend towards increased resources use as compared to patients with susceptible "other" BSI, respectively.

Cellulose Nanocrystal Membranes as Excipients for Drug Delivery Systems

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Ananda M. Barbosa

2016-12-01

Full Text Available In this work, cellulose nanocrystals (CNCs were obtained from flax fibers by an acid hydrolysis assisted by sonochemistry in order to reduce reaction times. The cavitation inducted during hydrolysis resulted in CNC with uniform shapes, and thus further pretreatments into the cellulose are not required. The obtained CNC exhibited a homogeneous morphology and high crystallinity, as well as typical values for surface charge. Additionally, CNC membranes were developed from CNC solution to evaluation as a drug delivery system by the incorporation of a model drug. The drug delivery studies were carried out using chlorhexidine (CHX as a drug and the antimicrobial efficiency of the CNC membrane loaded with CHX was examined against Gram-positive bacteria Staphylococcus aureus (S. Aureus. The release of CHX from the CNC membranes is determined by UV-Vis. The obtaining methodology of the membranes proved to be simple, and these early studies showed a potential use in antibiotic drug delivery systems due to the release kinetics and the satisfactory antimicrobial activity.

An Injectable System for Local and Sustained Release of Antimicrobial Agents in the Periodontal Pocket.

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Morelli, Laura; Cappelluti, Martino Alfredo; Ricotti, Leonardo; Lenardi, Cristina; Gerges, Irini

2017-08-01

Periodontitis treatments usually require local administration of antimicrobial drugs with the aim to reduce the bacterial load inside the periodontal pocket. Effective pharmaceutical treatments may require sustained local drug release for several days in the site of interest. Currently available solutions are still not able to fulfill the clinical need for high-quality treatments, mainly in terms of release profiles and patients' comfort. This work aims to fill this gap through the development of an in situ gelling system, capable to achieve controlled and sustained release of antimicrobial agents for medium-to-long-term treatments. The system is composed of micrometer-sized β-cyclodextrin-based hydrogel (bCD-Jef-MPs), featured by a strong hydrophilic character, suspended in a synthetic block-co-polymer solution (Poloxamer 407), which is capable to undergo rapid thermally induced sol-gel phase transition at body temperature. The chemical structure of bCD-Jef-MPs was confirmed by cross-correlating data from Fourier transform infrared (FTIR) spectroscopy, swelling test, and degradation kinetics. The thermally induced sol-gel phase transition is demonstrated by rheometric tests. The effectiveness of the described system to achieve sustained release of antimicrobial agents is demonstrated in vitro, using chlorhexidine digluconate as a drug model. The results achieved in this work disclose the potential of the mentioned system in effectively treating periodontitis lesions. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Antimicrobial Resistance in Food Animals and the Environment in Nigeria: A Review

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Nurudeen Olalekan Oloso

2018-06-01

Full Text Available Antimicrobial resistance (AMR has emerged as a global health threat, which has elicited a high-level political declaration at the United Nations General Assembly, 2016. In response, member countries agreed to pay greater attention to the surveillance and implementation of antimicrobial stewardship. The Nigeria Centre for Disease Control called for a review of AMR in Nigeria using a “One Health approach”. As anecdotal evidence suggests that food animal health and production rely heavily on antimicrobials, it becomes imperative to understand AMR trends in food animals and the environment. We reviewed previous studies to curate data and evaluate the contributions of food animals and the environment (2000–2016 to the AMR burden in Nigeria using a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA flowchart focused on three areas: Antimicrobial resistance, residues, and antiseptics studies. Only one of the 48 antimicrobial studies did not report multidrug resistance. At least 18 bacterial spp. were found to be resistant to various locally available antimicrobials. All 16 residue studies reported high levels of drug residues either in the form of prevalence or concentration above the recommended international limit. Fourteen different “resistotypes” were found in some commonly used antiseptics. High levels of residues and AMR were found in food animals destined for the human food chain. High levels of residues and antimicrobials discharged into environments sustain the AMR pool. These had evolved into potential public health challenges that need attention. These findings constitute public health threats for Nigeria’s teeming population and require attention.

Heavy metals in liquid pig manure in light of bacterial antimicrobial resistance

International Nuclear Information System (INIS)

Hölzel, Christina S.; Müller, Christa; Harms, Katrin S.; Mikolajewski, Sabine; Schäfer, Stefanie; Schwaiger, Karin; Bauer, Johann

2012-01-01

Heavy metals are regularly found in liquid pig manure, and might interact with bacterial antimicrobial resistance. Concentrations of heavy metals were determined by atomic spectroscopic methods in 305 pig manure samples and were connected to the phenotypic resistance of Escherichia coli (n=613) against 29 antimicrobial drugs. Concentrations of heavy metals (/kg dry matter) were 0.08–5.30 mg cadmium, 1.1–32.0 mg chrome, 22.4–3387.6 mg copper, <2.0–26.7 mg lead, <0.01–0.11 mg mercury, 3.1–97.3 mg nickel and 93.0–8239.0 mg zinc. Associated with the detection of copper and zinc, resistance rates against β-lactams were significantly elevated. By contrast, the presence of mercury was significantly associated with low antimicrobial resistance rates of Escherichia coli against β-lactams, aminoglycosides and other antibiotics. Effects of subinhibitory concentrations of mercury on bacterial resistance against penicillins, cephalosporins, aminoglycosides and doxycycline were also demonstrated in a laboratory trial. Antimicrobial resistance in the porcine microflora might be increased by copper and zinc. By contrast, the occurrence of mercury in the environment might, due to co-toxicity, act counter-selective against antimicrobial resistant strains.

Human Antimicrobial Peptides and Proteins

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Guangshun Wang

2014-05-01

medicine to combat drug-resistant superbugs, fungi, viruses, parasites, or cancer. Alternatively, multiple factors (e.g., albumin, arginine, butyrate, calcium, cyclic AMP, isoleucine, short-chain fatty acids, UV B light, vitamin D, and zinc are able to induce the expression of antimicrobial peptides, opening new avenues to the development of anti-infectious drugs.

Antimicrobial resistance

DEFF Research Database (Denmark)

Llor, Carl; Bjerrum, Lars

2014-01-01

Antimicrobial resistance is a global public health challenge, which has accelerated by the overuse of antibiotics worldwide. Increased antimicrobial resistance is the cause of severe infections, complications, longer hospital stays and increased mortality. Overprescribing of antibiotics......-the-counter sale of antibiotics, the use of antimicrobial stewardship programmes, the active participation of clinicians in audits, the utilization of valid rapid point-of-care tests, the promotion of delayed antibiotic prescribing strategies, the enhancement of communication skills with patients with the aid...

Antimicrobial Resistance

Science.gov (United States)

... least 10 countries (Australia, Austria, Canada, France, Japan, Norway, Slovenia, South Africa, Sweden and the United Kingdom ... plan Global report on surveillance Country situation analysis Policy to combat antimicrobial resistance More on antimicrobial resistance ...

Antimicrobial Resistance

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... can prevent and manage antimicrobial resistance. It is collaborating with partners to strengthen the evidence base and ... on the global action plan. WHO has been leading multiple initiatives to address antimicrobial resistance: World Antibiotic ...

Antimicrobial resistance, infection control and planning for pandemics: the importance of knowledge transfer in healthcare resilience and emergency planning.

Science.gov (United States)

Cole, Jennifer

Over the last 70 years, the efficacy, ready availability and relatively low cost of antimicrobial drugs - medicines that kill microorganisms such as bacteria and viruses or inhibit their multiplication, growth and pathogenic action - has led to their considerable overuse. It is estimated that nearly 50 per cent of all antimicrobial use in hospitals is unnecessary or inappropriate1 while in neonatal care, the figure is even higher, with infection confirmed in only five per cent of neonates treated with antibiotics.2 The more antimicrobials are used, the faster the microorganisms they target evolve into new, resistant strains, a natural process of evolution that threatens to undermine the tremendous life-saving potential of these drugs. Antimicrobial resistance (AMR) is a growing concern not only for the healthcare sector3 but also, increasingly, for security and resilience. Pandemic influenza, comparable only to 'Catastrophic terrorist attacks' at the top of the UK's National Risk Register4 may well result from the emergence of a strain that cannot be treated effectively with currently available drugs or from one that quickly develops resistance to the stockpiled countermeasures. Multidrug-resistant tuberculosis impacts on immigration policy, methicillin-resistant Staphylococcus aureus (MRSA), a major cause of hospital-acquired infections is an ongoing challenge for the health sector and the increase in drug-resistant strains of malaria is problematic both in its own right and as an additional consequence of climate change. AMR places a significant burden on international governments and tackling it requires changes to thinking across a number of government departments. In 2011, the Transatlantic Taskforce on Antimicrobial Resistance (TATFAR) published Recommendations for future collaboration between the US and EU1 and both the EU and the UK's Department of Health have recently developed new AMR strategies and Action Plans. This paper will explore the cross

Rauvolfia grandiflora (Apocynaceae extract interferes with staphylococcal density, enterotoxin production and antimicrobial activity

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Lanamar de Almeida Carlos

2010-10-01

Full Text Available Staphylococci bacteria are involved in many human and animal infections and development of alternative antimicrobial drugs against pathogenic bacteria is of great interest to the pharmaceutical industry. This study investigated the in vitro effect of Rauvolfia grandiflora methanol extract (root bark fraction (RGE on the density of ATCC strains of Staphylococcus aureus and Staphylococcus epidermidis, and a clinical enterotoxin-producer, S. aureus bovine strain. The alkaloid, isoreserpiline, obtained from dichloromethane extract of R. grandiflora was ineffective against the strains tested. After incubation of staphylococci strains in the presence of 1.2 mg.mL-1 RGE, a significant inhibition of cell growth was observed using both spectrophotometry and ELISA assays. Twelve drugs were evaluated for their antimicrobial effects on culture RGE-treated cells using the disk diffusion method. Penicillin resistant strains became sensitive to the drug after RGE treatment. Furthermore, enterotoxin production by RGE-treated S. aureus was evaluated using a standardized ELISA method. Although staphylococcal LSA 88 bovine strain cells remained viable after exposure to the extract, enterotoxin production was precluded in 20% after RGE treatment. Significant interference in staphylococci cell density, drug sensitivity and enterotoxin secretion was observed after treatment. The study highlights the necessity to find new methods of disease prevention and new antibiotic therapies against staphylococcal infections.

Rauvolfia grandiflora (apocynaceae) extract interferes with staphylococcal density, enterotoxin production and antimicrobial activity.

Science.gov (United States)

de Almeida Carlos, Lanamar; da Silva Amaral, Kenas Aguiar; Curcino Vieira, Ivo José; Mathias, Leda; Braz-Filho, Raimundo; Silva Samarão, Solange; Vieira-da-Motta, Olney

2010-07-01

Staphylococci bacteria are involved in many human and animal infections and development of alternative antimicrobial drugs against pathogenic bacteria is of great interest to the pharmaceutical industry. This study investigated the in vitro effect of Rauvolfia grandiflora methanol extract (root bark fraction) (RGE) on the density of ATCC strains of Staphylococcus aureus and Staphylococcus epidermidis, and a clinical enterotoxin-producer, S. aureus bovine strain. The alkaloid, isoreserpiline, obtained from dichloromethane extract of R. grandiflora was ineffective against the strains tested. After incubation of staphylococci strains in the presence of 1.2 μg.mL(-1) RGE, a significant inhibition of cell growth was observed using both spectrophotometry and ELISA assays. Twelve drugs were evaluated for their antimicrobial effects on culture RGE-treated cells using the disk diffusion method. Penicillin resistant strains became sensitive to the drug after RGE treatment. Furthermore, enterotoxin production by RGE-treated S. aureus was evaluated using a standardized ELISA method. Although staphylococcal LSA 88 bovine strain cells remained viable after exposure to the extract, enterotoxin production was precluded in 20% after RGE treatment. Significant interference in staphylococci cell density, drug sensitivity and enterotoxin secretion was observed after treatment. The study highlights the necessity to find new methods of disease prevention and new antibiotic therapies against staphylococcal infections.

A Simple Assay to Screen Antimicrobial Compounds Potentiating the Activity of Current Antibiotics

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Junaid Iqbal

2013-01-01

Full Text Available Antibiotic resistance continues to pose a significant problem in the management of bacterial infections, despite advances in antimicrobial chemotherapy and supportive care. Here, we suggest a simple, inexpensive, and easy-to-perform assay to screen antimicrobial compounds from natural products or synthetic chemical libraries for their potential to work in tandem with the available antibiotics against multiple drug-resistant bacteria. The aqueous extract of Juglans regia tree bark was tested against representative multiple drug-resistant bacteria in the aforementioned assay to determine whether it potentiates the activity of selected antibiotics. The aqueous extract of J. regia bark was added to Mueller-Hinton agar, followed by a lawn of multiple drug-resistant bacteria, Salmonella typhi or enteropathogenic E. coli. Next, filter paper discs impregnated with different classes of antibiotics were placed on the agar surface. Bacteria incubated with extract or antibiotics alone were used as controls. The results showed a significant increase (>30% in the zone of inhibition around the aztreonam, cefuroxime, and ampicillin discs compared with bacteria incubated with the antibiotics/extract alone. In conclusion, our assay is able to detect either synergistic or additive action of J. regia extract against multiple drug-resistant bacteria when tested with a range of antibiotics.

Preparation, characterization, and antimicrobial activity of nanoemulsions incorporating citral essential oil

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Wen-Chien Lu

2018-01-01

Full Text Available Citral is a typical essential oil used in the food, cosmetic, and drug industries and has shown antimicrobial activity against microorganisms. Citral is unstable and hydrophobic under normal storage conditions, so it can easily lose its bactericide activity. Nanoemulsion technology is an excellent way to hydrophilize, microencapsulate, and protect this compound. In our studies, we used a mixed surfactant to form citral-in-water nanoemulsions, and attempted to optimize the formula for preparing nanoemulsions. Citral-in-water nanoemulsions formed at So 0.4 to 0.6 and ultrasonic power of 18 W for 120 seconds resulted in a droplet size of < 100 nm for nanoemulsions. The observed antimicrobial activities were significantly affected by the formulation of the nanoemulsions. The observed relationship between the formulation and activity can lead to the rational design of nanoemulsion-based delivery systems for essential oils, based on the desired function of antimicrobials in the food, cosmetics, and agrochemical industries.

In Vitro and In Vivo Activities of Antimicrobials against Nocardia brasiliensis

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Gomez-Flores, Alejandra; Welsh, Oliverio; Said-Fernández, Salvador; Lozano-Garza, Gerardo; Tavarez-Alejandro, Roman Erick; Vera-Cabrera, Lucio

2004-01-01

In Mexico mycetomas are mostly produced by Nocardia brasiliensis, which can be isolated from about 86% of cases. In the present work, we determined the sensitivities of 30 N. brasiliensis strains isolated from patients with mycetoma to several groups of antimicrobials. As a first screening step we carried out disk diffusion assays with 44 antimicrobials, including aminoglycosides, cephalosporins, penicillins, quinolones, macrolides, and some others. In these assays we observed that some antimicrobials have an effect on more than 66% of the strains: linezolid, amikacin, gentamicin, isepamicin, netilmicin, tobramycin, minocycline, amoxicillin-clavulanic acid, piperacillin-tazobactam, nitroxolin, and spiramycin. Drug activity was confirmed quantitatively by the broth microdilution method. Amoxicillin-clavulanic acid, linezolid, and amikacin, which have been used to treat patients, were tested in an experimental model of mycetoma in BALB/c mice in order to validate the in vitro results. Linezolid showed the highest activity in vivo, followed by the combination amoxicillin-clavulanic acid and amikacin. PMID:14982772

A brief multi-disciplinary review on antimicrobial resistance in medicine and its linkage to the global environmental microbiota

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Cantas, L.; Shah, Syed Q. A.; Cavaco, L. M.; Manaia, C. M.; Walsh, F.; Popowska, M.; Garelick, H.; Bürgmann, H.; Sørum, H.

2013-01-01

The discovery and introduction of antimicrobial agents to clinical medicine was one of the greatest medical triumphs of the 20th century that revolutionized the treatment of bacterial infections. However, the gradual emergence of populations of antimicrobial-resistant pathogenic bacteria resulting from use, misuse, and abuse of antimicrobials has today become a major global health concern. Antimicrobial resistance (AMR) genes have been suggested to originate from environmental bacteria, as clinically relevant resistance genes have been detected on the chromosome of environmental bacteria. As only a few new antimicrobials have been developed in the last decade, the further evolution of resistance poses a serious threat to public health. Urgent measures are required not only to minimize the use of antimicrobials for prophylactic and therapeutic purposes but also to look for alternative strategies for the control of bacterial infections. This review examines the global picture of antimicrobial resistance, factors that favor its spread, strategies, and limitations for its control and the need for continuous training of all stake-holders i.e., medical, veterinary, public health, and other relevant professionals as well as human consumers, in the appropriate use of antimicrobial drugs. PMID:23675371

Antimicrobial resistance in E. coli and Salmonella spp. isolates from calves in southern Chile

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Luis Hervé-Claude

2017-09-01

Full Text Available Objective: Description of antimicrobial resistance in E. coli and Salmonella spp. isolates from calves <30 days of age from southern Chile. Material and methods: Necropsy and microbiology reports of 107 calves <30 days of age received at the Animal Pathology Institute between 2002 and 2015 were considered. Additionally, an antimicrobial resistance score was generated to allow comparisons among isolates with different antimicrobial susceptibility profiles. Results: There was no clear trend in antimicrobial resistance during the study period, with similar levels of resistance for E. coli, β-hemolytic E. coli and Salmonella spp. Approximately 50% of isolates were sensitive to antimicrobials, and between 19 and 36% of samples showed possible extended- or pan- drug resistance. Multiple different antimicrobial resistance patterns were found, including 32 for E. coli, 17 for β-hemolytic E. coli and 10 for Salmonella spp. Conclusions: Overall, E. coli samples were most sensitive to ceftriaxone; β-hemolytic E. coli to florfenicol; and Salmonella spp. to gentamicin. In contrast, these agents were resistant to amoxicillin, ampicillin and oxytetracycline respectively. This study is unique in its approach and provides useful information for veterinarians and producers on the antibiotic resistance patterns of bacteria posing a serious threat to calves. These results can help field veterinarians to control and treat bacterial diarrhea in calves.

Low hanging fruit in infectious disease drug development.

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Kraus, Carl N

2008-10-01

Cost estimates for developing new molecular entities (NME) are reaching non-sustainable levels and coupled with increasing regulatory requirements and oversight have led many pharmaceutical sponsors to divest their anti-microbial development portfolios [Projan SJ: Why is big Pharma getting out of anti-bacterial drug discovery?Curr Opin Microbiol 2003, 6:427-430] [Spellberg B, Powers JH, Brass EP, Miller LG, Edwards JE, Jr: Trends in antimicrobial drug development: implications for the future.Clin Infect Dis 2004, 38:1279-1286]. Operational issues such as study planning and execution are significant contributors to the overall cost of drug development that can benefit from the leveraging of pre-randomization data in an evidence-based approach to protocol development, site selection and patient recruitment. For non-NME products there is even greater benefit from available data resources since these data may permit smaller and shorter study programs. There are now many available open source intelligence (OSINT) resources that are being integrated into drug development programs, permitting an evidence-based or 'operational epidemiology' approach to study planning and execution.

Diversity and antimicrobial activities of actinobacteria isolated from tropical mangrove sediments in Malaysia.

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Lee, Learn-Han; Zainal, Nurullhudda; Azman, Adzzie-Shazleen; Eng, Shu-Kee; Goh, Bey-Hing; Yin, Wai-Fong; Ab Mutalib, Nurul-Syakima; Chan, Kok-Gan

2014-01-01

The aim of this study was to isolate and identify Actinobacteria from Malaysia mangrove forest and screen them for production of antimicrobial secondary metabolites. Eighty-seven isolates were isolated from soil samples collected at 4 different sites. This is the first report to describe the isolation of Streptomyces, Mycobacterium, Leifsonia, Microbacterium, Sinomonas, Nocardia, Terrabacter, Streptacidiphilus, Micromonospora, Gordonia, and Nocardioides from mangrove in east coast of Malaysia. Of 87 isolates, at least 5 isolates are considered as putative novel taxa. Nine Streptomyces sp. isolates were producing potent antimicrobial secondary metabolites, indicating that Streptomyces isolates are providing high quality metabolites for drug discovery purposes. The discovery of a novel species, Streptomyces pluripotens sp. nov. MUSC 135(T) that produced potent secondary metabolites inhibiting the growth of MRSA, had provided promising metabolites for drug discovery research. The biosynthetic potential of 87 isolates was investigated by the detection of polyketide synthetase (PKS) and nonribosomal polyketide synthetase (NRPS) genes, the hallmarks of secondary metabolites production. Results showed that many isolates were positive for PKS-I (19.5%), PKS-II (42.5%), and NRPS (5.7%) genes, indicating that mangrove Actinobacteria have significant biosynthetic potential. Our results highlighted that mangrove environment represented a rich reservoir for isolation of Actinobacteria, which are potential sources for discovery of antimicrobial secondary metabolites.

Animation of Antimicrobial Resistance

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Full Text Available ... video) Animation of Antimicrobial Resistance (text version) Arabic Translation of Animation of Antimicrobial Resistance Chinese Translation of Animation of Antimicrobial Resistance French Translation of ...

Application of luciferase assay for ATP to antimicrobial drug susceptibility

Science.gov (United States)

Chappelle, E. W.; Picciolo, G. L.; Vellend, H.; Tuttle, S. A.; Barza, M. J.; Weinstein, L. (Inventor)

1977-01-01

The susceptibility of bacteria, particularly those derived from body fluids, to antimicrobial agents is determined in terms of an ATP index measured by culturing a bacterium in a growth medium. The amount of ATP is assayed in a sample of the cultured bacterium by measuring the amount of luminescent light emitted when the bacterial ATP is reacted with a luciferase-luciferin mixture. The sample of the cultured bacterium is subjected to an antibiotic agent. The amount of bacterial adenosine triphosphate is assayed after treatment with the antibiotic by measuring the luminescent light resulting from the reaction. The ATP index is determined from the values obtained from the assay procedures.

Antimicrobial resistance of mastitis pathogens.

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Oliver, Stephen P; Murinda, Shelton E

2012-07-01

Antibiotics are used extensively in the dairy industry to combat disease and to improve animal performance. Antibiotics such as penicillin, cephalosporin, streptomycin, and tetracycline are used for the treatment and prevention of diseases affecting dairy cows caused by a variety of gram-positive and gram-negative bacteria. Antibiotics are often administrated routinely to entire herds to prevent mastitis during the dry period. An increase in the incidence of disease in a herd generally results in increased use of antimicrobials, which in turn increases the potential for antibiotic residues in milk and the potential for increased bacterial resistance to antimicrobials. Continued use of antibiotics in the treatment and prevention of diseases of dairy cows will continue to be scrutinized. It is clear that strategies employing the prudent use of antimicrobials are needed. This clearly illustrates the importance of effective herd disease prevention and control programs. Based on studies published to date, scientific evidence does not support widespread, emerging resistance among mastitis pathogens to antibacterial drugs even though many of these antibiotics have been used in the dairy industry for treatment and prevention of disease for several decades. However, it is clear that use of antibiotics in dairy cows can contribute to increased antimicrobial resistance. While antimicrobial resistance does occur, we are of the opinion that the advantages of using antibiotics for the treatment of mastitis far outweigh the disadvantages. The clinical consequences of antimicrobial resistance of dairy pathogens affecting humans appear small. Antimicrobial resistance among dairy pathogens, particularly those found in milk, is likely not a human health concern as long as the milk is pasteurized. However, there are an increasing number of people who choose to consume raw milk. Transmission of an antimicrobial-resistant mastitis pathogen and/or foodborne pathogen to humans could occur

Evaluating bionanoparticle infused fungal metabolites as a novel antimicrobial agent

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Kartikeya Rajpal

2016-01-01

Full Text Available Therapeutic properties of fungal metabolites and silver nanoparticles have been well documented. While fungal metabolites have been used for centuries as medicinal drugs, potential of biogenic silver nanoparticles has recently received attention. We have evaluated the antimicrobial potential of Aspergillus terreus crude extract, silver nanoparticles and an amalgamation of both against four pathogenic bacterial strains. Antimicrobial activity of the following was evaluated – A. terreus extract, biogenic silver nanoparticles, and a mixture containing extract and nanoparticles. Four pathogenic bacteria - Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, and Bacillus cereus were used as test organisms. Phenol, flavonoid, and alkaloid content of extract were determined to understand the chemical profile of the fungus. The extract contained significantly high amounts of phenols, flavonoids, and alkaloids. The extract and biogenic silver nanoparticle exhibited significant antibacterial activity at concentrations of 10 μg/ml and 1 μg/ml, respectively. When used in combination, the extract-nanoparticle mixture showed equally potent antibacterial activity at a much lower concentration of 2.5 μg/ml extract + 0.5 μg/ml nanoparticle. Given its high antibacterial potential, the fungal extract can be a promising source of novel drug lead compounds. The extract – silver nanoparticle mixture exhibited synergism in their antibacterial efficacy. This property can be further used to formulate new age drugs.

Preparation and characterization of antimicrobial nano-hydroxyapatite composites

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Yu, Juhong [The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, College of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Chu, Xiaobing [The First Affiliated Hospital, Zhejiang Chinese Medicine University, Hangzhou 310006 (China); Cai, Yurong [The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, College of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Tong, Peijian [The First Affiliated Hospital, Zhejiang Chinese Medicine University, Hangzhou 310006 (China); Yao, Juming, E-mail: yaoj@zstu.edu.cn [The Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Ministry of Education, College of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou 310018 (China)

2014-04-01

Deep infection of prosthesis is one of the most frequent complications after joint replacement. One of the most effective ways is to introduce directly some antibiotics in the local site of the surgery. In the present study, an antimicrobial composite has been fabricated using nano-hydroxyapatite particles as carriers for the antimicrobial drug of vancomycin hydrochloride (VAN) and the mixture of oxidation sodium alginate (OSA) and gelatin (GT) as a sticky matrix. Samples have been characterized using X-ray diffraction instrument (XRD), field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM) and Fourier transform infrared (FTIR) spectra, Brunauer–Emmett–Teller (BET) methods, the rotational rheometer and the texture analyzer. The release of VAN from nano-hydroxyapatite (nHAP) particles was detected by the ultraviolet–visible (UV–vis) spectrophotometer and then bactericidal property of the composite was evaluated using the Staphylococcus aureus (S. aureus) as a bacterial model. Experimental results showed that the composite possessed an adhesive property derived from the gel of OSA and GT, which implied that the composite could bond directly to the fracture surface of bones in surgery. Furthermore, VAN was loaded efficiently on the surface of nHAP particles and could be released slowly from these particles, which endowed the composite with an obvious and continuous antimicrobial performance. The sticky and antimicrobial composite may has a potential application in arthroplasty to overcome deep infection in a simple and direct manner. - Highlights: • A sticky and antimicrobial composite has been designed to overcome deep infection. • The composite was composed of antibiotic, antibiotic carrier and a viscous matrix. • The sticky matrix was obtained by blending of oxidation sodium alginate and gelatin. • Hydroxyapatite nanoparticle could be used as carrier to control release of antibiotic.

Preparation and characterization of antimicrobial nano-hydroxyapatite composites

International Nuclear Information System (INIS)

Yu, Juhong; Chu, Xiaobing; Cai, Yurong; Tong, Peijian; Yao, Juming

2014-01-01

Deep infection of prosthesis is one of the most frequent complications after joint replacement. One of the most effective ways is to introduce directly some antibiotics in the local site of the surgery. In the present study, an antimicrobial composite has been fabricated using nano-hydroxyapatite particles as carriers for the antimicrobial drug of vancomycin hydrochloride (VAN) and the mixture of oxidation sodium alginate (OSA) and gelatin (GT) as a sticky matrix. Samples have been characterized using X-ray diffraction instrument (XRD), field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM) and Fourier transform infrared (FTIR) spectra, Brunauer–Emmett–Teller (BET) methods, the rotational rheometer and the texture analyzer. The release of VAN from nano-hydroxyapatite (nHAP) particles was detected by the ultraviolet–visible (UV–vis) spectrophotometer and then bactericidal property of the composite was evaluated using the Staphylococcus aureus (S. aureus) as a bacterial model. Experimental results showed that the composite possessed an adhesive property derived from the gel of OSA and GT, which implied that the composite could bond directly to the fracture surface of bones in surgery. Furthermore, VAN was loaded efficiently on the surface of nHAP particles and could be released slowly from these particles, which endowed the composite with an obvious and continuous antimicrobial performance. The sticky and antimicrobial composite may has a potential application in arthroplasty to overcome deep infection in a simple and direct manner. - Highlights: • A sticky and antimicrobial composite has been designed to overcome deep infection. • The composite was composed of antibiotic, antibiotic carrier and a viscous matrix. • The sticky matrix was obtained by blending of oxidation sodium alginate and gelatin. • Hydroxyapatite nanoparticle could be used as carrier to control release of antibiotic

ACVIM Consensus Statement on Therapeutic Antimicrobial Use in Animals and Antimicrobial Resistance

OpenAIRE

Weese, J.S.; Gigu?re, S.; Guardabassi, L.; Morley, P.S.; Papich, M.; Ricciuto, D.R.; Sykes, J.E.

2015-01-01

The epidemic of antimicrobial resistant infections continues to challenge, compromising animal care, complicating food animal production and posing zoonotic disease risks. While the overall role of therapeutic antimicrobial use in animals in the development AMR in animal and human pathogens is poorly defined, veterinarians must consider the impacts of antimicrobial use in animal and take steps to optimize antimicrobial use, so as to maximize the health benefits to animals while minimizing the...

Antimicrobial Activity of Ephedra pachyclada Methanol Extract on Some Enteric Gram Negative Bacteria Which Causes Nosocomial Infections by Agar Dilution Method

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Amin Sadeghi Dosari

2016-10-01

Full Text Available Background Past history indicates that plants were served as an important source of medicine. Otherwise, in developing countries people use medicinal plants against infectious disease because they cannot afford expensive drugs. Due to increasing rate of drug-resistant diseases, there is an urgent need to detect novel antimicrobial compounds from medicinal plants. Objectives The aim of the present study was to determine Antimicrobial activity of Ephedra pachyclada methanol extract on some enteric Gram-negative bacteria which causes nosocomial infections by agar dilution method. Methods In this cross-sectional study, in order to examine the antimicrobial effects of Ephedra pachyclada extract on intestinal Gram-negative bacteria, we exposed them to 0/128, 0/25, 0/5, 1, 2, 4 and 8 mg/mL of the extract. Ephedra pachyclada was collected from Jiroft Heights and methanolic extract was prepared with maceration method, during which, 50 gr powder of Ephedra pachyclada was dissolved in 300 mL of 80% methanol. Results In this study, the antibacterial effects of Ephedra pachyclada extract on Gram-negative bacteria such as Pseudomonas aeruginosa, Escherichia coli (PTCC-O157, Escherichia coli (ATCC-25922, Klebsiella pnemoniae, Serratia marcescens was investigated, defining the minimum inhibitory concentration (MIC by agar dilution method. It has been demonstrated that methanolic extract of Ephedra pachyclada affect intestinal Gram-negative bacteria. Conclusions The result showed that, Ephedra pachyclada extract has effective antimicrobial ingredients which are cheap and readily available. It can be used for medicinal purposes in the production of antimicrobial drug.

Novel natural food antimicrobials.

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Juneja, Vijay K; Dwivedi, Hari P; Yan, Xianghe

2012-01-01

Naturally occurring antimicrobial compounds could be applied as food preservatives to protect food quality and extend the shelf life of foods and beverages. These compounds are naturally produced and isolated from various sources, including plants, animals and microorganisms, in which they constitute part of host defense systems. Many naturally occurring compounds, such as nisin, plant essential oils, and natamycin, have been widely studied and are reported to be effective in their potential role as antimicrobial agents against spoilage and pathogenic microorganisms. Although some of these natural antimicrobials are commercially available and applied in food processing, their efficacy, consumer acceptance and regulation are not well defined. This manuscript reviews natural antimicrobial compounds with reference to their applications in food when applied individually or in combination with other hurdles. It also reviews the mechanism of action of selected natural antimicrobials, factors affecting their antimicrobial activities, and future prospects for use of natural antimicrobials in the food industry.

Synthesis, Spectral and Antimicrobial Studies of Some N(2)-Substituted Tetrahydroindazoles

International Nuclear Information System (INIS)

Amirthaganesan, Shanmugasundaram; Aridoss, Gopalakrishnan; Park, Keun Soo; Lim, Kwon Taek; Jeong, Yeon Tae

2010-01-01

A series of N(2)-benzothiazolyl substituted tetrahydroindazoles has been synthesized via cyclic β keto esters. Optimum reaction condition was found as acidic toluene and effect of higher acidity towards substituted hydrazines in situ was described. Synthesized compounds have been achieved as single isomer and characterized by using 1D and 2D NMR spectral reports. Antimicrobial screening was carried out for the synthesized compounds along with a series of N(2)-pyridyl tetrahydroindazoles. 1 The results of the in vitro antimicrobial screening studies revealed that compounds 13, 16 against Staphylococcus aureus, 11 against Escherichia coli, 10-12, 16 against Pseudomonas aeruginosa and 12 against Klebsiella pneumoniae recorded almost two-fold better activity compared to the standard drug used

Antimicrobial peptides as potential anti-biofilm agents against multidrug-resistant bacteria.

Science.gov (United States)

Chung, Pooi Yin; Khanum, Ramona

2017-08-01

Bacterial resistance to commonly used drugs has become a global health problem, causing increased infection cases and mortality rate. One of the main virulence determinants in many bacterial infections is biofilm formation, which significantly increases bacterial resistance to antibiotics and innate host defence. In the search to address the chronic infections caused by biofilms, antimicrobial peptides (AMP) have been considered as potential alternative agents to conventional antibiotics. Although AMPs are commonly considered as the primitive mechanism of immunity and has been extensively studied in insects and non-vertebrate organisms, there is now increasing evidence that AMPs also play a crucial role in human immunity. AMPs have exhibited broad-spectrum activity against many strains of Gram-positive and Gram-negative bacteria, including drug-resistant strains, and fungi. In addition, AMPs also showed synergy with classical antibiotics, neutralize toxins and are active in animal models. In this review, the important mechanisms of action and potential of AMPs in the eradication of biofilm formation in multidrug-resistant pathogen, with the goal of designing novel antimicrobial therapeutics, are discussed. Copyright © 2017. Published by Elsevier B.V.

Antimicrobial activity of Algerian honey on subclinical mastitis pathogens isolated from goat's milk

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A. Bourabah

2014-04-01

Full Text Available Aim: The aim of the present study was to determine the susceptibility of subclinical mastitis pathogens isolated from goat's milk and to evaluate the antimicrobial activity of Algerian honey on mastitis causing bacteria. Materials and Methods: The antibacterial activity against the isolated bacteria was evaluated by determining the Minimal Inhibitory Concentration (MIC, using the agar incorporation method. Results: The results showed that both Micrococcus spp. and Klebsiella spp. were susceptible to Streptomycin and tetracycline, while Pseudomonas aeruginosa, E coli, Enterobacter spp., Bacillus spp., and Coagulase Negative Staphyloccoci (CNS were preferentially susceptible to Streptomycin. However, Streptococcus D was the most resistant to the tested antibiotics whereas Staphylococcus aureus was the most susceptible to all the studied antibiotics. As regards to the antimicrobial activity of honey, the measured values were comprised between 11 and 14%. Conclusion: The results reveal that antimicrobial drugs susceptibility tests in goat subclinical mastitis might be necessary before the treatment. Algerian honey exhibited in vitro antimicrobial activity against different isolated bacteria in goat mastitis.

Sustained antimicrobial activity and reduced toxicity of oxidative biocides through biodegradable microparticles.

Science.gov (United States)

Sofokleous, Panagiotis; Ali, Shanom; Wilson, Peter; Buanz, Asma; Gaisford, Simon; Mistry, Dharmit; Fellows, Adrian; Day, Richard M

2017-12-01

The spread of antibiotic-resistant pathogens requires new treatments. Small molecule precursor compounds that produce oxidative biocides with well-established antimicrobial properties could provide a range of new therapeutic products to combat resistant infections. The aim of this study was to investigate a novel biomaterials-based approach for the manufacture, targeted delivery and controlled release of a peroxygen donor (sodium percarbonate) combined with an acetyl donor (tetraacetylethylenediamine) to deliver local antimicrobial activity via a dynamic equilibrium mixture of hydrogen peroxide and peracetic acid. Entrapment of the pre-cursor compounds into hierarchically structured degradable microparticles was achieved using an innovative dry manufacturing process involving thermally induced phase separation (TIPS) that circumvented compound decomposition associated with conventional microparticle manufacture. The microparticles provided controlled release of hydrogen peroxide and peracetic acid that led to rapid and sustained killing of multiple drug-resistant organisms (methicillin-resistant Staphylococcus aureus and carbapenem-resistant Escherichia coli) without associated cytotoxicity in vitro nor intracutaneous reactivity in vivo. The results from this study demonstrate for the first time that microparticles loaded with acetyl and peroxygen donors retain their antimicrobial activity whilst eliciting no host toxicity. In doing so, it overcomes the detrimental effects that have prevented oxidative biocides from being used as alternatives to conventional antibiotics. The manuscript explores a novel approach to utilize the antimicrobial activity of oxidative species for sustained killing of multiple drug-resistant organisms without causing collateral tissue damage. The results demonstrate, for the first time, the ability to load pre-cursor compounds into porous polymeric structures that results in their release and conversion into oxidative species in a

Oral antimicrobials increase antimicrobial resistance in porcine E. coli--a systematic review.

Science.gov (United States)

Burow, E; Simoneit, C; Tenhagen, B-A; Käsbohrer, A

2014-03-01

Administration of antimicrobials to livestock increases the risk of antimicrobial resistance (AMR) in commensal bacteria. Antimicrobials in pig production are usually administered per pen via feed which implies treatment of sick alongside with healthy animals. The objective of this systematic literature review was to investigate the effect of orally administered antimicrobials on AMR in Escherichia coli of swine. Studies published in peer reviewed journals were retrieved from the international online databases ISI Web of Knowledge, PubMed, Scopus and the national electronic literature data base of Deutsches Institut für Medizinische Dokumentation und Information. The studies were assessed using the eligibility criteria English or German language, access to full paper version, defined treatment and control group (initial value or non-treatment) as well as administration and resistance testing of the same antimicrobial class. In the qualitative synthesis, only studies were included presenting the summary measures odds ratio or prevalence of resistance, the category of the applied antimicrobial and the dosage. An effect of the antimicrobial on AMR in E. coli was evaluated as an "increase", "no effect" or "decrease" if the odds or alternatively the prevalence ratio were >1.0, 1.0 or antimicrobial substance and dosage was missing in 4 and 5 of the 11 finally selected studies. The 36 identified trials were inhomogenous in usage and provision of information on sample size. Oral administration of antimicrobials increases the risk of AMR in E. coli from swine. There is however a lack of studies on the impact of dosage and longitudinal effects of treatment. The published studies have a number of issues concerning their scientific quality. More high quality research is needed to better address and quantifiy the effect of orally administered antimicrobials on AMR in swine. Copyright © 2014 Elsevier B.V. All rights reserved.

World Health Organization (WHO) guidelines on use of medically important antimicrobials in food-producing animals.

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Aidara-Kane, Awa; Angulo, Frederick J; Conly, John M; Minato, Yuki; Silbergeld, Ellen K; McEwen, Scott A; Collignon, Peter J

2018-01-01

Antimicrobial use in food-producing animals selects for antimicrobial resistance that can be transmitted to humans via food or other transmission routes. The World Health Organization (WHO) in 2005 ranked the medical importance of antimicrobials used in humans. In late 2017, to preserve the effectiveness of medically important antimicrobials for humans, WHO released guidelines on use of antimicrobials in food-producing animals that incorporated the latest WHO rankings. WHO commissioned systematic reviews and literature reviews, and convened a Guideline Development Group (GDG) of external experts free of unacceptable conflicts-of-interest. The GDG assessed the evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, and formulated recommendations using a structured evidence-to-decision approach that considered the balance of benefits and harms, feasibility, resource implications, and impact on equity. The resulting guidelines were peer-reviewed by an independent External Review Group and approved by the WHO Guidelines Review Committee. These guidelines recommend reductions in the overall use of medically important antimicrobials in food-producing animals, including complete restriction of use of antimicrobials for growth promotion and for disease prevention (i.e., in healthy animals considered at risk of infection). These guidelines also recommend that antimicrobials identified as critically important for humans not be used in food-producing animals for treatment or disease control unless susceptibility testing demonstrates the drug to be the only treatment option. To preserve the effectiveness of medically important antimicrobials, veterinarians, farmers, regulatory agencies, and all other stakeholders are urged to adopt these recommendations and work towards implementation of these guidelines.

Restrictions on antimicrobial use in food animal production: an international regulatory and economic survey

Science.gov (United States)

2013-01-01

Background The administration of antimicrobial drugs to food animals at low doses for extended durations for growth promotion and disease prevention has been linked to the global health crisis of antimicrobial resistance. Internationally, multiple jurisdictions have responded by restricting antimicrobial use for these purposes, and by requiring a veterinary prescription to use these drugs in food animals. Opponents of these policies have argued that restrictions have been detrimental to food animal production where they have been adopted. Methods We surveyed the antimicrobial use policies of 17 political jurisdictions outside of the United States with respect to growth promotion, disease prevention, and veterinary oversight, and reviewed the available evidence regarding their production impacts, including measures of animal health. Jurisdictions were included if they were a top-five importer of a major U.S. food animal product in 2011, as differences between the policies of the U.S. and other jurisdictions may lead to trade barriers to U.S. food animal product exports. Jurisdictions were also included if information on their policies was publicly available in English. We searched the peer-reviewed and grey literatures and corresponded with jurisdictions’ U.S. embassies, regulators, and local experts. Results Jurisdictions were categorized by whether they prohibit use of antimicrobials for growth promotion and/or use of antimicrobials without a veterinary prescription. Of the 17 jurisdictions surveyed, six jurisdictions have prohibited both types of use, five jurisdictions have prohibited one use but not the other use, and five jurisdictions have not prohibited either use, while information was not available for one jurisdiction. Data on the production impacts of these prohibitions were limited, although available data, especially from Denmark and Sweden, suggest that restrictions on growth promotion use can be implemented with minimal production consequences

Restrictions on antimicrobial use in food animal production: an international regulatory and economic survey.

Science.gov (United States)

Maron, Dina Fine; Smith, Tyler J S; Nachman, Keeve E

2013-10-16

The administration of antimicrobial drugs to food animals at low doses for extended durations for growth promotion and disease prevention has been linked to the global health crisis of antimicrobial resistance. Internationally, multiple jurisdictions have responded by restricting antimicrobial use for these purposes, and by requiring a veterinary prescription to use these drugs in food animals. Opponents of these policies have argued that restrictions have been detrimental to food animal production where they have been adopted. We surveyed the antimicrobial use policies of 17 political jurisdictions outside of the United States with respect to growth promotion, disease prevention, and veterinary oversight, and reviewed the available evidence regarding their production impacts, including measures of animal health. Jurisdictions were included if they were a top-five importer of a major U.S. food animal product in 2011, as differences between the policies of the U.S. and other jurisdictions may lead to trade barriers to U.S. food animal product exports. Jurisdictions were also included if information on their policies was publicly available in English. We searched the peer-reviewed and grey literatures and corresponded with jurisdictions' U.S. embassies, regulators, and local experts. Jurisdictions were categorized by whether they prohibit use of antimicrobials for growth promotion and/or use of antimicrobials without a veterinary prescription. Of the 17 jurisdictions surveyed, six jurisdictions have prohibited both types of use, five jurisdictions have prohibited one use but not the other use, and five jurisdictions have not prohibited either use, while information was not available for one jurisdiction. Data on the production impacts of these prohibitions were limited, although available data, especially from Denmark and Sweden, suggest that restrictions on growth promotion use can be implemented with minimal production consequences. A majority of leading U.S. trade

Synthesis and Antimicrobial Evaluation of Some New Fluoro Formazans

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Avinash Taterao Shinde

2016-05-01

Full Text Available A series of fluoro substituted formazan derivatives has been synthesized from the salt of diazonium chloride & fluoro schiff base in pyridine. The structure of newly synthesized formazans were established based on IR, 1H NMR and mass spectral data. All the synthesized compounds were screened for their antimicrobial activity. Some of the compounds showed very good activity compared to standard drugs against all pathogenic bacteria and fungi.

Molecular serotyping and antimicrobial resistance profiles of Actinobacillus pleuropneumoniae isolated from pigs in South Korea.

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Kim, Boram; Hur, Jin; Lee, Ji Yeong; Choi, Yoonyoung; Lee, John Hwa

2016-09-01

Actinobacillus pleuropneumoniae (APP) causes porcine pleuropneumonia (PP). Serotypes and antimicrobial resistance patterns in APP isolates from pigs in Korea were examined. Sixty-five APP isolates were genetically serotyped using standard and multiplex PCR (polymerase chain reaction). Antimicrobial susceptibilities were tested using the standardized disk-agar method. PCR was used to detect β-lactam, gentamicin and tetracycline-resistance genes. The random amplified polymorphic DNA (RAPD) patterns were determined by PCR. Korean pigs predominantly carried APP serotypes 1 and 5. Among 65 isolates, one isolate was sensitive to all 12 antimicrobials tested in this study. Sixty-two isolates was resistant to tetracycline and 53 isolates carried one or five genes including tet(B), tet(A), tet(H), tet(M)/tet(O), tet(C), tet(G) and/or tet(L)-1 markers. Among 64 strains, 9% and 26.6% were resistance to 10 and three or more antimicrobials, respectively. Thirteen different antimicrobial resistance patterns were observed and RAPD analysis revealed a separation of the isolates into two clusters: cluster II (6 strains resistant to 10 antimicrobials) and cluster I (the other 59 strains). Results show that APP serotypes 1 and 5 are the most common in Korea, and multi-drug resistant strains are prevalent. RAPD analysis demonstrated that six isolates resistant to 10 antimicrobials belonged to the same cluster.

Improving antimicrobial prescribing: implementation of an antimicrobial i.v.-to-oral switch policy.

Science.gov (United States)

McCallum, A D; Sutherland, R K; Mackintosh, C L

2013-01-01

Antimicrobial stewardship programmes reduce the risk of hospital associated infections (HAI) and antimicrobial resistance, and include early intravenous-to-oral switch (IVOS) as a key stewardship measure. We audited the number of patients on intravenous antimicrobials suitable for oral switch, assessed whether prescribing guidelines were followed and reviewed prescribing documentation in three clinical areas in the Western General Hospital, Edinburgh, in late 2012. Following this, the first cycle results and local guidelines were presented at a local level and at the hospital grand rounds, posters with recommendations were distributed, joint infection consult and antimicrobial rounds commenced and an alert antimicrobial policy was introduced before re-auditing in early 2013. We demonstrate suboptimal prescribing of intravenous antimicrobials, with 43.9% (43/98) of patients eligible for IVOS at the time of auditing. Only 56.1% (55/98) followed empiric prescribing recommendations. Documentation of antimicrobial prescribing was poor with stop dates recorded in 14.3%, indication on prescription charts in 18.4% and in the notes in 90.8%. The commonest reason for deferring IVOS was deteriorating clinical condition or severe sepsis. Further work to encourage prudent antimicrobial prescribing and earlier consideration of IVOS is required.

Antimicrobial resistance programs in canada 1995-2010: a critical evaluation

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Conly John M

2012-02-01

Full Text Available Abstract Background In Canada, systematic efforts for controlling antibiotic resistance began in 1997 following a national Consensus Conference. The Canadian strategy produced 27 recommendations, one of which was the formation of the Canadian Committee on Antibiotic Resistance (CCAR. In addition several other organizations began working on a national or provincial basis over the ensuing years on one or more of the 3 identified core areas of the strategy. Critical evaluation of the major programs within Canada which focused on antimicrobial resistance and the identified core components has not been previously conducted. Findings Data was collected from multiple sources to determine the components of four major AMR programs that were considered national based on their scope or in the delivery of their mandates. Assessment of program components was adapted from the report from the International Forum on Antibiotic Resistance colloquium. Most of the programs used similar tools but only the Do Bugs Need Drugs Program (DBND had components directed towards day cares and schools. Surveillance programs for antimicrobial resistant pathogens have limitations and/or significant sources of bias. Overall, there has been a 25.3% decrease in oral antimicrobial prescriptions in Canada since 1995, mainly due to decreases in β lactams, sulphonamides and tetracyclines in temporal association with multiple programs with the most comprehensive and sustained national programs being CCAR and DBND. Conclusions Although there has been a substantial decrease in oral antimicrobial prescriptions in Canada since 1995, there remains a lack of leadership and co-ordination of antimicrobial resistance activities.

Evolution of antimicrobial resistance of Salmonella enteritidis (1972–2005

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Jermaine Khumalo

2014-11-01

Full Text Available With the extensive use of antibiotics in livestock production, surveillance revealed an increase in Salmonella resistance to the commonly used antimicrobials in veterinary and public health. This serious threat to health care is further exacerbated by the limited epidemiological information about the common zoonotic agent, Salmonella enteritidis, required to determine antibiotic therapy. The aim was to characterise the antimicrobial resistance patterns of S. enteritidis isolates across different timelines (1972–2005 with accompanying genetic changes being investigated. Thirty-seven stored S. enteritidis isolates were collected from the Central Veterinary Laboratory, Harare, with antimicrobial susceptibility determined against eight antibiotics. Plasmids were isolated to analyse any genetic variation. An overall significant increase in resistance (p < 0.05 to nalidixic acid (0% – 10%, ampicillin (14.3% – 50%, tetracycline (14.3% – 30% and erythromycin (71.4% – 100% was observed across the timeline. However, the highest rates of susceptibility were maintained for gentamicin, sulphamethoxazole-trimethoprim, kanamycin and chloramphenicol. We report an increase in multidrug resistance (MDR of 14.2% – 50% with an increase in resistotypes and plasmid profiles across the timeline. Eleven plasmid profiles were obtained in the 37 isolates studied with a minority of isolates (21.6%, 8/37 harbouring a 54 kb plasmid, commonly serovar-specific. A concerning increase in antimicrobial resistance to commonly administered drugs was observed across the timeline. The surge in MDR is of great concern and implies the need for consistent antimicrobial stewardship. No correlation was observed between the plasmid and antibiotic profiles.