Witch Hazel Significantly Improves the Efficacy of Commercially Available Teat Dips

Bovine intramammary infections (IMIs) are the main cause of economic loss in milk production. Antibiotics are often ineffective in treating infections due to antimicrobial resistance and the formation of bacterial biofilms that enhance bacterial survival and persistence. Teat dips containing germicides are recommended to prevent new IMIs and improve udder health and milk quality. IMIs are often caused by staphylococci, which are Gram-positive bacteria that become pathogenic by forming biofilms and producing toxins. As a model for a teat dip (DIP), the BacStop iodine-based teat dip (DIP) was used. Witch hazel extract (whISOBAX (WH)) was tested because it contains a high concentration of the anti-biofilm/anti-toxin phenolic compound hamamelitannin. We found that the minimal inhibitory or bactericidal concentrations of DIP against planktonic S. epidermidis cells increased up to 160-fold in the presence of WH, and that DIP was 10-fold less effective against biofilm cells. While both DIP and WH are effective in inhibiting the growth of S. aureus, only WH inhibits toxin production (tested for enterotoxin-A). Importantly, WH also significantly enhances the antibacterial effect of DIP against Gram-negative bacteria that can cause IMIs, like Escherichia coli and Pseudomonas aeruginosa. Put together, these results suggest that the antibacterial activity of DIP combined with WH is significantly higher, and thus have potential in eradicating bacterial infections, both in acute (planktonic-associated) and in chronic (biofilm-associated) conditions.

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Contemporary threats of bacterial infections in freshwater fish

Journal of Veterinary Research ◽

10.2478/jvetres-2018-0037 ◽

2018 ◽

Vol 62 (3) ◽

pp. 261-267 ◽

Cited By ~ 9

Author(s):

Agnieszka Pękala-Safińska

Keyword(s):

Bacterial Infections ◽

Clinical Signs ◽

Freshwater Ecosystems ◽

Streptococcus Iniae ◽

Gram Negative Bacteria ◽

Positive Bacterium ◽

Gram Positive ◽

Gram Positive Bacteria ◽

Fish Pathology ◽

Dynamic Variations

AbstractChanges occurring in freshwater ecosystems seem to be fundamental in the development of all microorganisms, including those pathogenic to fish. This has been especially evident in recent years during which dynamic variations in bacterial fish pathology have been observed. Gram-negative bacteria commonly known to be pathogenic to fish, likeAeromonasspp.,Flavobacteriumspp.,Pseudomonasspp., andShewanella putrefaciensare replaced by other species, which until now have not been known to be virulent or even conditionally pathogenic to fish. Nowadays, among these other speciesAcinetobacterspp.,Plesiomonas shigelloides,Sphingomonas paucimobilis, andStenotrophomonas maltophiliaare the most frequently isolated from fish exhibiting clinical signs of disease. Two Gram-positive bacteria have become pathogens of particular importance in fish pathology in Poland:Lactococcus garviaeandStreptococcus iniae. In addition, infections caused by the Gram-positive bacteriumKocuria rhizophilahave appeared in recent years. This bacterium has not been known until now to be pathogenic to fish. Therefore, this infection could be called an emergent disease.

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Lactate production by aerobic bacteria grown in cerebrospinal fluid.

Clinical Chemistry ◽

10.1093/clinchem/30.11.1875 ◽

1984 ◽

Vol 30 (11) ◽

pp. 1875-1876 ◽

Cited By ~ 10

Author(s):

F L Kiechle ◽

M A Kamela ◽

R W Starnes

Keyword(s):

Cerebrospinal Fluid ◽

Bacterial Meningitis ◽

Lactate Concentration ◽

Lactate Production ◽

Aerobic Bacteria ◽

Gram Negative Bacteria ◽

High Concentration ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria

Abstract The source of the abnormally high concentration of lactate in the cerebrospinal fluid in patients with bacterial meningitis is not known. It may represent a bacterial metabolite. To determine whether cerebrospinal fluid possesses appropriate substrates to support the growth of pathogenic aerobic bacteria, three Gram-positive and nine Gram-negative bacteria were separately inoculated in pooled normal cerebrospinal fluid. After incubation for 24 h, all Gram-positive bacteria increased lactate, eight Gram-negative bacteria decreased lactate, and one Gram-negative bacteria failed to significantly change the lactate concentration. We conclude that lactate produced in cerebrospinal fluid in patients with aerobic bacterial meningitis is not necessarily a bacterial metabolite.

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Bacteriocins, Antimicrobial Peptides from Bacterial Origin: Overview of Their Biology and Their Impact against Multidrug-Resistant Bacteria

Microorganisms ◽

10.3390/microorganisms8050639 ◽

2020 ◽

Vol 8 (5) ◽

pp. 639 ◽

Cited By ~ 13

Author(s):

Alexis Simons ◽

Kamel Alhanout ◽

Raphaël E. Duval

Keyword(s):

Antimicrobial Resistance ◽

Bacterial Infections ◽

Antimicrobial Agents ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Gram Negative Bacteria ◽

Multidrug Resistant Bacteria ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Further Development

Currently, the emergence and ongoing dissemination of antimicrobial resistance among bacteria are critical health and economic issue, leading to increased rates of morbidity and mortality related to bacterial infections. Research and development for new antimicrobial agents is currently needed to overcome this problem. Among the different approaches studied, bacteriocins seem to be a promising possibility. These molecules are peptides naturally synthesized by ribosomes, produced by both Gram-positive bacteria (GPB) and Gram-negative bacteria (GNB), which will allow these bacteriocin producers to survive in highly competitive polymicrobial environment. Bacteriocins exhibit antimicrobial activity with variable spectrum depending on the peptide, which may target several bacteria. Already used in some areas such as agro-food, bacteriocins may be considered as interesting candidates for further development as antimicrobial agents used in health contexts, particularly considering the issue of antimicrobial resistance. The aim of this review is to present an updated global report on the biology of bacteriocins produced by GPB and GNB, as well as their antibacterial activity against relevant bacterial pathogens, and especially against multidrug-resistant bacteria.

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Toxicity of hydrogen peroxide produced by electroplated coatings to pathogenic bacteria

Canadian Journal of Microbiology ◽

10.1139/w98-030 ◽

1998 ◽

Vol 44 (5) ◽

pp. 441-447 ◽

Cited By ~ 9

Author(s):

Zhi-Hong Zhao ◽

Yoshikazu Sakagami ◽

Tetsuya Osaka

Keyword(s):

Hydrogen Peroxide ◽

Metal Ions ◽

Pathogenic Bacteria ◽

Methicillin Resistant Staphylococcus Aureus ◽

Survival Rates ◽

Gram Negative Bacteria ◽

Bacterial Survival ◽

Gram Positive Bacteria ◽

Inhibitory Ability ◽

Nickel Zinc

The ability of various electroplated coatings (cobalt, zinc, copper, and cobalt-containing alloys of nickel, zinc, chromium, etc.) to inhibit the growth of pathogenic bacteria (Gram-positive bacteria Enterococcus faecalis and methicillin-resistant Staphylococcus aureus and Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa, andKlebsiella pneumoniae) was determined by a drop-method antibacterial experiment. The amounts of H2O2 produced and metal ions dissolved from the surfaces of various electroplated coatings were measured and it was found that the inhibitory ability of coatings corresponded to the amounts of H2O2 produced. The more significant the inhibition of the coating to bacterial growth, the greater the amount of H2O2 production. In addition, the bacterial survival rates on the surfaces of coatings were almost zero when H2O2 was produced in amounts greater than 10-6 mmol/cm2. However, the dominant concentrations of metal ions dissolved from coatings were outside of the bacterial lethal range.Key words: electroplated coatings, pathogenic bacteria, inhibitory ability, hydrogen peroxide.

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whISOBAXTM Inhibits Bacterial Pathogenesis and Enhances the Effect of Antibiotics

Antibiotics ◽

10.3390/antibiotics9050264 ◽

2020 ◽

Vol 9 (5) ◽

pp. 264 ◽

Cited By ~ 1

Author(s):

Reuven Rasooly ◽

Hwang-Yong Choi ◽

Paula Do ◽

Gianluca Morroni ◽

Lucia Brescini ◽

...

Keyword(s):

Gallic Acid ◽

Staphylococcus Epidermidis ◽

Biofilm Formation ◽

Bacterial Infections ◽

Phenolic Content ◽

Toxin Production ◽

Gram Negative Bacteria ◽

Persistent Infections ◽

Toxin Inhibition

As bacteria are becoming more resistant to commonly used antibiotics, alternative therapies are being sought. whISOBAX (WH) is a witch hazel extract that is highly stable (tested up to 2 months in 37 °C) and contains a high phenolic content, where 75% of it is hamamelitannin and traces of gallic acid. Phenolic compounds like gallic acid are known to inhibit bacterial growth, while hamamelitannin is known to inhibit staphylococcal pathogenesis (biofilm formation and toxin production). WH was tested in vitro for its antibacterial activity against clinically relevant Gram-positive and Gram-negative bacteria, and its synergy with antibiotics determined using checkerboard assays followed by isobologram analysis. WH was also tested for its ability to suppress staphylococcal pathogenesis, which is the cause of a myriad of resistant infections. Here we show that WH inhibits the growth of all bacteria tested, with variable efficacy levels. The most WH-sensitive bacteria tested were Staphylococcus epidermidis, Staphylococcus aureus, Enterococcus faecium and Enterococcus faecalis, followed by Acinetobacter baumannii, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Streptococcus agalactiae and Streptococcus pneumoniae. Furthermore, WH was shown on S. aureus to be synergistic to linezolid and chloramphenicol and cumulative to vancomycin and amikacin. The effect of WH was tested on staphylococcal pathogenesis and shown here to inhibit biofilm formation (tested on S. epidermidis) and toxin production (tested on S. aureus Enterotoxin A (SEA)). Toxin inhibition was also evident in the presence of subinhibitory concentrations of ciprofloxacin that induces pathogenesis. Put together, our study indicates that WH is very effective in inhibiting the growth of multiple types of bacteria, is synergistic to antibiotics, and is also effective against staphylococcal pathogenesis, often the cause of persistent infections. Our study thus suggests the benefits of using WH to combat various types of bacterial infections, especially those that involve resistant persistent bacterial pathogens.

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Aptamer Affinity-Bead Mediated Capture and Displacement of Gram-Negative Bacteria Using Acoustophoresis

Micromachines ◽

10.3390/mi10110770 ◽

2019 ◽

Vol 10 (11) ◽

pp. 770

Author(s):

SangWook Lee ◽

Byung Woo Kim ◽

Hye-Su Shin ◽

Anna Go ◽

Min-Ho Lee ◽

...

Keyword(s):

Binding Affinity ◽

High Purity ◽

Bacterial Infections ◽

High Volume ◽

Flow Mode ◽

Separation Performance ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria

Here, we report a simple and effective method for capturing and displacement of gram-negative bacteria using aptamer-modified microbeads and acoustophoresis. As acoustophoresis allows for simultaneous washing and size-dependent separation in continuous flow mode, we efficiently obtained gram-negative bacteria that showed high affinity without any additional washing steps. The proposed device has a simple and efficient channel design, utilizing a long, square-shaped microchannel that shows excellent separation performance in terms of the purity, recovery, and concentration factor. Microbeads (10 µm) coated with the GN6 aptamer can specifically bind gram-negative bacteria. After incubation of bacteria culture sample with aptamer affinity bead, gram-negative bacteria-bound microbeads, and other unbound/contaminants can be separated by size with high purity and recovery. The device demonstrated excellent separation performance, with high recovery (up to 98%), high purity (up to 99%), and a high-volume rate (500 µL/min). The acoustophoretic separation performances were conducted using 5 Gram-negative bacteria and 5 Gram-positive bacteria. Thanks to GN6 aptamer’s binding affinity, aptamer affinity bead also showed binding affinity to multiple strains of gram-negative bacteria, but not to gram-positive bacteria. GN6 coated bead can capture Gram-negative bacteria but not Gram-positive bacteria. This study may present a different perspective in the field of early diagnosis in bacterial infectious diseases. In addition to detecting living bacteria or bacteria-derived biomarkers, this protocol can be extended to monitoring the contamination of water resources and may aid quick responses to bioterrorism and pathogenic bacterial infections.

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Epidemiology of patients with central nervous system infections, mainly neurosurgical patients: a retrospective study from 2012 to 2019 in a teaching hospital in China

BMC Infectious Diseases ◽

10.1186/s12879-021-06561-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Zheng Zhang ◽

Yan Song ◽

Jianbang Kang ◽

Surong Duan ◽

Qi Li ◽

...

Keyword(s):

Risk Factors ◽

Escherichia Coli ◽

Central Nervous System ◽

Nervous System ◽

Retrospective Study ◽

Bacterial Infections ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Cns Infections

Abstract Background Central nervous system (CNS) infections are relatively rare but are associated with high mortality worldwide. Empirical antimicrobial therapy is crucial for the survival of patients with CNS infections, and should be based on the knowledge of the pathogen distribution and antibiotic sensitivities. The aim of this study was to investigate the features of pathogens in patients with CNS infections in North China and evaluate the risk factors for mortality and multi-drug-resistant (MDR) bacterial infections. Methods A retrospective study was conducted with patients with positive cerebrospinal fluid (CSF) cultures in a teaching hospital from January 2012 to December 2019. The following data were collected: demographic characteristics, laboratory data, causative organisms and antimicrobial sensitivity results. Data were analyzed with SPSS 16.0. Univariate analysis and binary logistic regression analyses were performed to identify the risk factors for mortality and MDR bacterial infections. Results A total of 72 patients were diagnosed with CNS infections, and 86 isolates were identified. The proportions of Gram-positive bacteria, Gram-negative bacteria and fungi were 59.3, 30.2 and 10.5%, respectively. The predominant Gram-positive bacteria was Coagulase-negative Staphylococci. Acinetobacter baumannii, Escherichia coli and Klebsiella spp. were the predominant Gram-negative bacteria. Compared to 2012–2015 years, the proportion of Gram-negative bacteria increased markedly during 2016–2019 years. Coagulase-negative Staphylococci, Streptococcus pneumoniae and Enterococcus faecium had 100% sensitivity to vancomycin, teicoplanin and linezolid. Acinetobacter baumannii and Klebsiella pneumoniae were 100% sensitive to tigecycline. Escherichia coli had 100% sensitivity to amikacin, meropenem and imipenem. The overall mortality rate in the 72 patients was 30.6%. In multivariate analysis, age > 50 years, pulmonary infections and CSF glucose level < the normal value were associated with poor outcomes. CSF adenosine deaminase level > the normal value and the presence of external ventricular drainage/lumbar cistern drainage were associated with MDR bacterial infections. Conclusions The mortality rate due to CNS infections reached 30.6% in our study. The proportion of Gram-negative bacteria has increased markedly in recent years. We should give particular attention to patients with risk factors for mortality and MDR bacterial infections mentioned above.

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Rapid demonstration of septic or infectious arthritis due to Gram-negative bacteria

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123830 ◽

1992 ◽

Vol 50 (1) ◽

pp. 686-687

Author(s):

Jacob S. Hanker ◽

Paul R. Gross ◽

Beverly L. Giammara

Keyword(s):

Chronic Arthritis ◽

Blood Cultures ◽

Gram Negative Bacteria ◽

Infectious Arthritis ◽

Bacterial Arthritis ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria

Blood cultures are positive in approximately only 50 per cent of the patients with nongonococcal bacterial infectious arthritis and about 20 per cent of those with gonococcal arthritis. But the concept that gram-negative bacteria could be involved even in chronic arthritis is well-supported. Gram stains are more definitive in staphylococcal arthritis caused by gram-positive bacteria than in bacterial arthritis due to gram-negative bacteria. In the latter situation where gram-negative bacilli are the problem, Gram stains are helpful for 50% of the patients; they are only helpful for 25% of the patients, however, where gram-negative gonococci are the problem. In arthritis due to gram-positive Staphylococci. Gramstained smears are positive for 75% of the patients.

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Antibacterial activity of magnesium oxide nanoparticles prepared by Calcination method

International Journal of Pharmaceutical Quality Assurance ◽

10.25258/ijpqa.10.3.25 ◽

2019 ◽

Vol 10 (03) ◽

Author(s):

Elaf Ayad Kadhem ◽

Miaad Hamzah Zghair ◽

Sarah , Hussam H. Tizkam, Shoeb Alahmad Salih Mahdi ◽

Hussam H. Tizkam ◽

Shoeb Alahmad

Keyword(s):

Antibacterial Activity ◽

Magnesium Oxide ◽

Diffusion Method ◽

Oxide Nanoparticles ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Magnesium Oxide Nanoparticles ◽

Agar Disc

magnesium oxide nanoparticles (MgO NPs) were prepared by simple wet chemical method using different calcination temperatures. The prepared NPs were characterized by Electrostatic Discharge (ESD), Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD). It demonstrates sharp intensive peak with the increase of crystallinty and increase of the size with varying morphologies with respect to increase of calcination temperature. Antibacterial studies were done on gram negative bacteria (E.coli) and gram positive bacteria (S.aureus) by agar disc diffusion method. The zones of inhibitions were found larger for gram positive bacteria than gram negative bacteria, this mean, antibacterial MgO NPs activity more active on gram positive bacteria than gram negative bacteria because of the structural differences. It was found that antibacterial activity of MgO NPs was found it has directly proportional with their concentration.

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Synthesis, Spectral and Antimicrobial Investigation of 2-(Naphthalenel-ylamino)-2- Phenylacetonitrile and 1, 10-Phenanthroline with Five Divalent Transition Metal Ions

International Journal of Pharmaceutical Quality Assurance ◽

10.25258/ijpqa.10.1.6 ◽

2019 ◽

Vol 10 (01) ◽

Author(s):

Mohammed Al-Amery1 ◽

Ashraf Saad Rasheed ◽

Dina A. Najeeb

Keyword(s):

Transition Metal ◽

Metal Ions ◽

Transition Metal Ions ◽

Molar Conductance ◽

Octahedral Geometry ◽

Mixed Ligand ◽

Gram Negative Bacteria ◽

Magnetic Studies ◽

Gram Positive Bacteria

Five new mixed ligand metal complexes have been synthesized by the reaction of divalent transition metal ions (Hg, Ni, Zn, Cu and Cd) with 2-(naphthalen-l-ylamino)-2-phenylacetonitrile (L1 ) and 1,10-phenanthroline (L2). The coordination likelihood of the two ligands toward metal ions has been suggested in the light of elemental analysis, UV-Vis spectra, FTIR, 1H-NMR, flam atomic absorption, molar conductance and magnetic studies. Results data suggest that the octahedral geometry for all the prepared complexes. Antibacterial examination of synthesized complexes in vitro was performed against four bacterias. Firstly, Gram-negative bacteria namely, Pseudomonas aerugin and Escherichia. Secondly, Gram-positive bacteria namely, Bacillus subtilis, Staphylococcuaurouss. Results data exhibit that the synthesized complexes exhibited more biological activity than tetracycline pharmaceutical.

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