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Biomaterials Apr 2022Emerging antimicrobial resistance in infections asks for novel intervention strategies. Galacto-oligosaccharides (GOS) might be attractive alternatives to antibiotics...
Emerging antimicrobial resistance in infections asks for novel intervention strategies. Galacto-oligosaccharides (GOS) might be attractive alternatives to antibiotics due to their anti-inflammatory and anti-adhesive properties. Mannheimia haemolytica is one of the major Pasteurellaceae associated with bovine lung infections. Using M. haemolytica, we demonstrated that GOS have the capacity to reduce bacterial viability and can be used as adjuvant to improve antibiotic efficacy. Using M. haemolytica-treated primary bronchial epithelial cells (PBECs) of calves, we identified the anti-adhesive and anti-invasive activities of GOS. The observed inhibition of cytokine/chemokine release and the prevention of airway epithelial barrier dysfunction in M. haemolytica-treated PBECs by GOS might be related to the downregulation of "toll-like receptor 4/nuclear factor-κB" pathway and the anti-invasive and anti-adhesive properties of GOS. Particularly, GOS lowered lipopolysaccharides- but not flagellin-induced cytokine/chemokine release in calf and human airway epithelial cells. Finally, we performed in vivo experiments in calves and demonstrated for the first time that intranasal application of GOS can relieve lung infections/inflammation and lower M. haemolytica positivity in the lungs without affecting clinical performance. These findings not only shed light on the anti-inflammatory mechanisms of GOS during lung infections, but GOS might also be a promising anti-bacterial agent for preventing (lung) infections.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Cattle; Humans; Lung; Mannheimia haemolytica; Oligosaccharides; Pneumonia
PubMed: 35286857
DOI: 10.1016/j.biomaterials.2022.121461 -
Clinical Infectious Diseases : An... Apr 2018We sought to determine if clinical data validate the dogma that bactericidal antibiotics are more clinically effective than bacteriostatic agents. We performed a...
We sought to determine if clinical data validate the dogma that bactericidal antibiotics are more clinically effective than bacteriostatic agents. We performed a systematic literature review of published, randomized, controlled trials (RCTs) that compared a bacteriostatic agent to a bactericidal agent in the treatment of clinical, bacterial infections. Of 56 identified trials published since 1985, 49 found no significant difference in efficacy between bacteriostatic and bactericidal agents. In 6 trials it was found that the bacteriostatic agent was superior to the bactericidal agent in efficacy. Only 1 trial found that the bactericidal agent was superior; in that case, the inferiority of the static agent was explainable by underdosing of the drug based on pharmacokinetic-pharmacodynamic analysis. Thus, virtually all available data from high-quality, RCTs demonstrate no intrinsic superiority of bactericidal compared to bacteriostatic agents. Other drug characteristics such as optimal dosing, pharmacokinetics, and tissue penetration may be more important efficacy drivers.
Topics: Anti-Bacterial Agents; Bacteria; Bacterial Infections; Humans; Microbial Sensitivity Tests; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 29293890
DOI: 10.1093/cid/cix1127 -
Biochemical Pharmacology Jun 2017An ideal antibiotic is an antibacterial agent that kills or inhibits the growth of all harmful bacteria in a host, regardless of site of infection without affecting... (Review)
Review
An ideal antibiotic is an antibacterial agent that kills or inhibits the growth of all harmful bacteria in a host, regardless of site of infection without affecting beneficial gut microbes (gut flora) or causing undue toxicity to the host. Sadly, no such antibiotics exist. What exist are many effective Gram-positive antibacterial agents as well as broad-spectrum agents that provide treatment of certain Gram-negative bacteria but not holistic treatment of all bacteria. However effectiveness of all antibacterial agents is being rapidly eroded due to resistance. This viewpoint provides an overview of today's antibiotics, challenges and potential path forward of discovery and development of new (ideal) antibiotics.
Topics: Anti-Bacterial Agents; Drug Discovery; Gram-Negative Bacteria; Humans; Microbial Sensitivity Tests
PubMed: 28087253
DOI: 10.1016/j.bcp.2017.01.003 -
Journal of Traditional Chinese Medicine... Aug 2021To investigate the anti-bacterial and anti-viral effects of Fengreqing oral liquid (, FRQ) in vitro and in vivo.
OBJECTIVE
To investigate the anti-bacterial and anti-viral effects of Fengreqing oral liquid (, FRQ) in vitro and in vivo.
METHODS
The minimum inhibitory concentrations of Fengreqing Oral Liquid against six gram-positive bacteria (Staphylococcus aureus, Streptococcus mutans, Peptostreptococcus anaerobius, Hemolytic streptococcus, Streptococcus pneumoniae, Klebsiella pneumoniae), seven gram-negative bacteria (Escherichia coli, Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Haemophilus influenzae, Helicobacter pylori, Pseudomonas aeruginosa, Gardnerella vaginalis) and Candida albicans were detected by the paper disc diffusion method. The inhibition rate of A/PuertoRico/8/34(H1N1) (PR8) influenza virus in different concentrations of Fengreqing oral solution was detected by chicken embryo method. CCK8 method was used to detect the half-cell infection of RSV, VSV and CVB3. The effect of FRQ on the survival curve of mice was detected by using co-infection model of Streptococcus pneumoniae and influenza virus.
RESULTS
In vitro, FRQ can inhibit Actinobacillus actinomycetemcomitans, Helicobacter pylori, Gardnerella vaginalis, Staphylococcus aureus, Streptococcus mutans and Streptococcus pneumoniae and has an antiviral effect on the envelope virus H1N1. In vivo, Fengreqing oral solution had therapeutic effect on influenza-Streptococcus pneumoniae co-infection in mice, significantly improving the survival rate of mice. The medium dose and low dose FRQ significantly prolonged the survival time of mice.
CONCLUSION
FRQ has good anti-bacterial and anti-viral effectsin vivo and in vitro.
Topics: Animals; Anti-Bacterial Agents; Antiviral Agents; Chick Embryo; Helicobacter pylori; Influenza A Virus, H1N1 Subtype; Mice; Microbial Sensitivity Tests; Staphylococcus aureus
PubMed: 34392645
DOI: 10.19852/j.cnki.jtcm.2021.03.005 -
Molecules (Basel, Switzerland) Aug 2023Rakicidin B1 was isolated and purified from the culture broth of a marine sp. as a potent anti-cancer agent, and lately the compound and its derivatives have firstly...
Rakicidin B1 was isolated and purified from the culture broth of a marine sp. as a potent anti-cancer agent, and lately the compound and its derivatives have firstly been found to possess anti- (CD) activity but with high cytotoxicity. Herein, following our previous discovery on anti-CD activity of Rakicidin B1, structure modification was performed at the OH position of Rakicidin B1 and a new Rakicidin B1-PEG hybrids FIMP2 was facilely designed and synthesized by conjugating the PEG2000 with the scaffolds of Rakicidin B1 via the linkage of carbamate. The cytotoxicity of the FIMP2 was first evaluated against three different cancer cell lines, including HCT-8 cells, PANC-1, and Caco-2, with IC values at 0.519 μM, 0.815 μM, and 0.586 μM, respectively. Obviously, as compared with a positive control group treated with Rakicidin B1, the IC value of FIMP2 increased by nearly 91-fold, 50-fold, and 67-fold, suggesting that the PEGylation strategy significantly reduced the cytotoxicity of FIMP2. Thus, this preliminary result may be beneficial to increase its safety index (SI) value due to the decreased cytotoxicity of FIMP2. In addition, this decreased cytotoxicity of FIMP2 was further confirmed based on a zebrafish screening model in vivo. Thereafter, the anti-CD activity of FIMP2 was evaluated in vivo, and its efficacy to treat CDI was found to be better than that of vancomycin. The mortality and recurrence rate of FIMP2 is not as low compared with that of vancomycin; these results demonstrated that compound FIMP2 is a new, promising anti-CD agent with significant efficacy against CD recurrence with low cytotoxicity towards bodies.
Topics: Humans; Animals; Anti-Bacterial Agents; Vancomycin; Caco-2 Cells; Zebrafish; Clostridioides difficile
PubMed: 37630404
DOI: 10.3390/molecules28166152 -
International Journal of Food... Jan 2021Recently, natural essential oils have been extensively studied for anti-bacterial application in foods due to their safety and high biological activity. Herein, Litsea...
Recently, natural essential oils have been extensively studied for anti-bacterial application in foods due to their safety and high biological activity. Herein, Litsea cubeba essential oil (LC-EO) was applied as a natural anti-bacterial agent for exploring its anti-bacterial mechanism against Enterohemorrhagic Escherichia coli O157:H7 (EHEC O157:H7). The LC-EO could effectively inhibit the growth of EHEC O157:H7 and the minimal inhibitory concentration (MIC) was 0.5 mg/mL. In the study of anti-bacterial mechanism, the LC-EO was proved with good membrane penetration ability, which could destroy bacterial cell structure and disorder membrane permeability, thereby causing the leakage of intracellular organic matters. Furthermore, the inhibitory effects of LC-EO on physiological metabolism of EHEC O157:H7, including respiratory metabolism, enzyme activity, the replication of nucleic acid and the transcription level of main virulence genes (stx1, stx2, ehxA, eae), were also demonstrated in this study. Specially, the possible action mechanism of different components of LC-EO on bacterial genetic material was revealed deeply on molecular level by the molecular docking technology. Finally, the results of application evaluation indicated that the addition of LC-EO at MIC in different vegetable juices could maintain anti-bacterial rate above 99.9% for 4 days without remarkable influence on foods sensory quality. The information in this study provides the necessary theoretical foundation for extending the application of LC-EO in food preservation.
Topics: Anti-Bacterial Agents; Escherichia coli O157; Escherichia coli Proteins; Food Preservation; Fruit and Vegetable Juices; Gene Expression Regulation, Bacterial; Litsea; Microbial Sensitivity Tests; Molecular Docking Simulation; Oils, Volatile
PubMed: 33257098
DOI: 10.1016/j.ijfoodmicro.2020.108989 -
Die Pharmazie Jun 2016The antimicrobial agent tyrothricin is a representative of the group of antimicrobial peptides (AMP). It is produced by Bacillus brevis and consists of tyrocidines and... (Review)
Review
The antimicrobial agent tyrothricin is a representative of the group of antimicrobial peptides (AMP). It is produced by Bacillus brevis and consists of tyrocidines and gramicidins. The compound mixture shows activity against bacteria, fungi and some viruses. A very interesting feature of AMPs is the fact, that even in vitro it is almost impossible to induce resistances. Therefore, this class of molecules is discussed as one group that could serve as next generation antibiotics and overcome the increasing problem of bacterial resistances. In daily practice, the application of tyrothricin containing formulations is relatively limited: It is used in sore throat medications and in agents for the healing of infected superficial and small-area wounds. However, due to the broad spectrum antimicrobial activity and the low risk of resistance development it is worth to consider further fields of application.
Topics: Animals; Anti-Bacterial Agents; Antifungal Agents; Antiviral Agents; Humans; Skin Diseases, Infectious; Structure-Activity Relationship; Tyrothricin; Wound Infection
PubMed: 27455547
DOI: No ID Found -
Molecules (Basel, Switzerland) Oct 2023Phytochemicals are plant secondary metabolites that show health benefits for humans due to their bioactivity. There is a huge variety of phytochemicals that have already... (Review)
Review
Phytochemicals are plant secondary metabolites that show health benefits for humans due to their bioactivity. There is a huge variety of phytochemicals that have already been identified, and these compounds can act as antimicrobial and neuroprotection agents. Due to their anti-microbial activity and neuroprotection, several phytochemicals might have the potency to be used as natural therapeutic agents, especially for infection and neurodegenerative disease, which have become a global health concern nowadays. According to previous research, there are some connections between infection and neurodegenerative diseases, especially Alzheimer's disease. Hence, this comprehensive review examines different kinds of phytochemicals from natural sources as potential therapeutic agents to reduce infection and improve neurodegenerative disease. An additional large-scale study is needed to establish the connection between infection and neurodegenerative disease and how phytochemicals could improve this condition.
Topics: Humans; Helicobacter pylori; Helicobacter Infections; Neuroprotective Agents; Neurodegenerative Diseases; Anti-Bacterial Agents; Phytochemicals
PubMed: 37894629
DOI: 10.3390/molecules28207150 -
Polish Journal of Microbiology 2013Bacteriocines are small peptides with anti-bacterial properties. They are produced both by Gram-positive and Gram-negative bacteria. Until now, a few hundred... (Review)
Review
Bacteriocines are small peptides with anti-bacterial properties. They are produced both by Gram-positive and Gram-negative bacteria. Until now, a few hundred bacteriocines were described. Classification of bacteriocines undergoes continuous alterations, as new developments regarding their structure, amino acid sequence and recognised mechanism of their action are available. Some of bacteriocins (lantibiotics) contain atypical amino acids, such as lantionine (Lan), methyllantionine (MeLan), dehydroalanine (Dha), dehydrobutyrine (Dhb), or D-alanine (D-Ala). The best recognized bacteriocines are produced by lactic acid bacteria, including nisine produced by strains of Lactococcus lactis. These bacteriocines have been recognized to be fully safe for humans. At present, nisine is used in food industry, as a preserving agent. Other lactic acid bacteria bacteriocines and probiotic preparations provide an alternative for antibiotics, and are used in food and in animal feed.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Bacteriocins; Humans; Protein Structure, Secondary
PubMed: 24459827
DOI: No ID Found -
Profiles of Drug Substances,... 2014A comprehensive profile of moxifloxacin HCl with 198 references is reported. A full description including nomenclature, formulae, elemental analysis, and appearance is... (Review)
Review
A comprehensive profile of moxifloxacin HCl with 198 references is reported. A full description including nomenclature, formulae, elemental analysis, and appearance is included. Methods of preparation for moxifloxacin HCl, its intermediates, and derivatives are fully described. In addition, the physical properties, analytical methods, stability, uses and applications, and pharmacology of moxifloxacin HCl are also discussed.
Topics: Animals; Anti-Bacterial Agents; Chemistry, Pharmaceutical; Drug Stability; Fluoroquinolones; Humans; Molecular Structure; Moxifloxacin; Tissue Distribution
PubMed: 24794910
DOI: 10.1016/B978-0-12-800173-8.00007-6