scholarly journals Antibacterial activity and mechanism of sanguinarine against Providencia rettgeri in vitro

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9543
Author(s):  
Qian Zhang ◽  
Yansi Lyu ◽  
Jingkai Huang ◽  
Xiaodong Zhang ◽  
Na Yu ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Crystal Violet ◽  
Membrane Integrity ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Crystal Violet Staining ◽  
Providencia Rettgeri ◽  
Intracellular Atp ◽  
Atp Concentration

Background Sanguinarine (SAG), a benzophenanthridine alkaloid, occurs in Papaveraceas, Berberidaceae and Ranunculaceae families. Studies have found that SAG has antioxidant, anti-inflammatory, and antiproliferative activities in several malignancies and that it exhibits robust antibacterial activities. However, information reported on the action of SAG against Providencia rettgeri is limited in the literature. Therefore, the present study aimed to evaluate the antimicrobial and antibiofilm activities of SAG against P. rettgeri in vitro. Methods The agar dilution method was used to determine the minimum inhibitory concentration (MIC) of SAG against P. rettgeri. The intracellular ATP concentration, intracellular pH (pHin), and cell membrane integrity and potential were measured. Confocal laser scanning microscopy (CLSM), field emission scanning electron microscopy (FESEM), and crystal violet staining were used to measure the antibiofilm formation of SAG. Results The MIC of SAG against P. rettgeri was 7.8 μg/mL. SAG inhibited the growth of P. rettgeri and destroyed the integrity of P. rettgeri cell membrane, as reflected mainly through the decreases in the intracellular ATP concentration, pHin and cell membrane potential and significant changes in cellular morphology. The findings of CLSM, FESEM and crystal violet staining indicated that SAG exhibited strong inhibitory effects on the biofilm formation of P. rettgeri and led to the inactivity of biofilm-related P. rettgeri cells.

scholarly journals In Vitro Antibacterial Activity and Mechanism of Vanillic Acid against Carbapenem-Resistant Enterobacter cloacae

Antibiotics ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 220 ◽  
Author(s):  
Weidong Qian ◽  
Yuting Fu ◽  
Miao Liu ◽  
Ting Wang ◽  
Jianing Zhang ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Membrane Potential ◽  
Cell Membrane ◽  
Crystal Violet ◽  
Vanillic Acid ◽  
Membrane Integrity ◽  
Enterobacter Cloacae ◽  
Carbapenem Resistant ◽  
Atp Concentration

Vanillic acid (VA) is a flavoring agent found in edible plants and fruits. Few recent studies exhibited robust antibacterial activity of VA against several pathogen microorganisms. However, little was reported about the effect of VA on carbapenem-resistant Enterobacter cloacae (CREC). The purpose of the current study was to assess in vitro antimicrobial and antibiofilm activities of VA against CREC. Here, minimum inhibitory concentrations (MIC) of VA against CREC was determined via gradient diffusion method. Furthermore, the antibacterial mode of VA against CREC was elucidated by measuring changes in intracellular adenosine triphosphate (ATP) concentration, intracellular pH (pHin), cell membrane potential and membrane integrity. In addition, antibiofilm formation of VA was measured by crystal violet assay and visualized with field emission scanning electron microscopy (FESEM) and confocal laser scanning microscopy (CLSM). The results showed that MIC of VA against E. cloacae was 600 μg/mL. VA was capable of inhibiting the growth of CREC and destroying the cell membrane integrity of CREC, as confirmed by the decrease of intracellular ATP concentration, pHin and membrane potential as well as distinctive variation in cellular morphology. Moreover, crystal violet staining, FESEM and CLSM results indicated that VA displayed robust inhibitory effects on biofilm formation of CREC and inactivated biofilm-related CREC cells. These findings revealed that VA exhibits potent antibacterial activity against CREC, and thus has potential to be exploited as a natural preservative to control the CREC associated infections.

scholarly journals Biofilm Formation and Methylene Blue-mediated Photodynamic Inactivation of Vibrio Parahaemolyticus in the Sea Food Industry

2020 ◽  
Vol 10 (3) ◽  
Author(s):  
Xiaoting Zhang ◽  
Qian Wu ◽  
Shuze Tang ◽  
William W Riley ◽  
Zhenqiang Chen
Keyword(s):  
Methylene Blue ◽  
Crystal Violet ◽  
Biofilm Formation ◽  
Vibrio Parahaemolyticus ◽  
Food Industry ◽  
Membrane Integrity ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Photodynamic Inactivation ◽  
Log Reduction

This study was conducted to better understand the mechanism of Vibrio Parahaemolyticus biofilm formation and to assess the inactivation effects of methylene blue-mediated photodynamic inactivation (PDI) technology as a preventative measure. Optical microscopy, following crystal violet staining, was used to observe the kinetics of V. parahaemolyticus biofilm formation. The crystal violet-based assay was performed in microtiter plates, and it was employed to determine which factors were most influential in the formation of the biofilms. Colony counting and confocal laser scanning microscopy (CLSM) were used to test the inactivation effect of methylene blue-mediated photodynamic technology on the biofilms. V. parahaemolyticus has the ability to form biofilms, as evidenced by their immediate adherence to glass surfaces and rapid maturity, within 24 h. High (7%) or low (0.5%) salinity was not conducive to the formation of biofilms, and rotational speed greater than 130 rpm also inhibited the process. A 4.05 log reduction in the concentration of viable biofilm cells was obtained with 100 μg/mL methylene blue and 20 min irradiation (24.996 J/cm2), but planktonic cells were more susceptible to the methylene blue-mediated photodynamic reaction (5.46 log reduction). The results presented here show that the methylene blue-mediated PDI technology is an effective means to inactivate V. parahaemolyticus by disrupting its membrane integrity and to inhibit the pathogen’s formation of protective biofilms. This technology is a valid tool that can be used to enhance food safety in the sea food industry.

scholarly journals Biofilm Forming Ability Of Salmonella Enteritidis In Vitro

2015 ◽  
Vol 65 (3) ◽  
pp. 371-389 ◽  
Author(s):  
Čabarkapa Ivana ◽  
Škrinjar Marija ◽  
Lević Jovanka ◽  
Kokić Bojana ◽  
Blagojev Nevena ◽  
...  
Keyword(s):  
Crystal Violet ◽  
Congo Red ◽  
Laser Scanning ◽  
Salmonella Enteritidis ◽  
Incubation Temperature ◽  
Three Dimensional ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Microtiter Plates

AbstractSalmonella entericaserotype Enteritidis is an important alimentary pathogen that recently gained special attention due to the ability of a large number of strains to form biofilms. Qualitative testing of biofilm forming ability was performed by observing the morphotype of the colonies on Congo Red agar and by conducting the pellicle test, while quantitative testing was carried out by Cristal violet assay on microtiter plates. A total of 14 isolates of S. Enteritidis were tested for biofilm forming ability, while Salmonella Enteritidis ATTC 13076 was used as the reference strain. Based on the morphotype of colonies cultivated on Congo Red agar at 25°C incubation temperature, among tested isolates three morphotypes were detected – red, dry and rough (rdar), brown, dry and rough (bdar) and smooth and white (saw). Half of the tested isolates demonstrated rdar morphotype. All isolates that showed a specific morphotype at this incubation temperature also formed the corresponding type of pellicle at the air-liquid interface. Additionally, comparing OD (optical density) values obtained by crystal violet test between groups of isolates that represent one of the three detected morphotypes (rdar, bdar and saw), statistically significant differences were detected. Based on OD values obtained by crystal violet test at both applied incubation temperatures, isolates were classified into three categories, regarding their ability to form biofilms: strong, moderate and weak biofilm producers. By comparing the amounts of the biofilms formed after 48h at 25°C and 37°C, statistically significant differences were noted (P<0.05). In this research we presented micrographs and a reconstruction of three-dimensional projections of biofilm developing phases of rdar morphotype isolates, which were obtained using confocal laser scanning microscopy.

Vacuoles Induced in Mammalian Cells by Helicobacter Cytotoxin are Acidic Organelles

1990 ◽  
Vol 48 (3) ◽  
pp. 168-169
Author(s):  
M. H. Chestnut ◽  
C. E. Catrenich
Keyword(s):  
Acridine Orange ◽  
Mammalian Cells ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Ulcer Disease ◽  
Gastroduodenal Disease ◽  
H Pylori

Helicobacter pylori is a non-invasive, Gram-negative spiral bacterium first identified in 1983, and subsequently implicated in the pathogenesis of gastroduodenal disease including gastritis and peptic ulcer disease. Cytotoxic activity, manifested by intracytoplasmic vacuolation of mammalian cells in vitro, was identified in 55% of H. pylori strains examined. The vacuoles increase in number and size during extended incubation, resulting in vacuolar and cellular degeneration after 24 h to 48 h. Vacuolation of gastric epithelial cells is also observed in vivo during infection by H. pylori. A high molecular weight, heat labile protein is believed to be responsible for vacuolation and to significantly contribute to the development of gastroduodenal disease in humans. The mechanism by which the cytotoxin exerts its effect is unknown, as is the intracellular origin of the vacuolar membrane and contents. Acridine orange is a membrane-permeant weak base that initially accumulates in low-pH compartments. We have used acridine orange accumulation in conjunction with confocal laser scanning microscopy of toxin-treated cells to begin probing the nature and origin of these vacuoles.

scholarly journals Effect of dissolution rate and subsequent ion release on cytocompatibility properties of borophosphate glasses

2019 ◽  
Vol 5 (1) ◽  
pp. 85-97
Author(s):  
Nusrat Sharmin ◽  
Mohammad S. Hasan ◽  
Md. Towhidul Islam ◽  
Chengheng Pang ◽  
Fu Gu ◽  
...  
Keyword(s):  
Dissolution Rate ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Ion Release ◽  
Scanning Calorimetry ◽  
Cell Culture Study ◽  
Borophosphate Glasses ◽  
Mg63 Cells

AbstractPresent work explores the relationship between the composition, dissolution rate, ion release and cytocompatibility of a series of borophosphate glasses. While, the base glass was selected to be 40mol%P2O5-16mol%CaO-24mol%MgO-20mol%Na2O, three B2O3 modified glass compositions were formulated by replacing Na2O with 1, 5 and 10 mol% B2O3. Ion release study was conducted using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The thermal scans of the glasses as determined by differential scanning calorimetry (DSC) revealed an increment in the thermal properties with increasing B2O3 content in the glasses. On the other hand, the dissolution rate of the glasses decreased with increasing B2O3 content. To identify the effect of boron ion release on the cytocompatibility properties of the glasses, MG63 cells were cultured on the surface of the glass discs. The in vitro cell culture study suggested that glasses with 5 mol% B2O3 (P40B5) showed better cell proliferation and metabolic activity as compares to the glasses with 10 mol% (P40B10) or with no B2O3 (P40B0). The confocal laser scanning microscopy (CLSM) images of live/dead stained MG63 cells attached to the surface of the glasses also revealed that the number of dead cells attached to P40B5 glasses were significantly lower than both P40B0 and P40B10 glasses.

scholarly journals Cephalosporin nitric oxide-donor prodrug DEA-C3D disperses biofilms formed by clinical cystic fibrosis isolates of Pseudomonas aeruginosa

2019 ◽  
Vol 75 (1) ◽  
pp. 117-125 ◽  
Author(s):  
Odel Soren ◽  
Ardeshir Rineh ◽  
Diogo G Silva ◽  
Yuming Cai ◽  
Robert P Howlin ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Clinical Isolates ◽  
Nitric Oxide Donor ◽  
Confocal Laser ◽  
Broth Microdilution Method

Abstract Objectives The cephalosporin nitric oxide (NO)-donor prodrug DEA-C3D (‘DiEthylAmin-Cephalosporin-3′-Diazeniumdiolate’) has been shown to initiate the dispersal of biofilms formed by the Pseudomonas aeruginosa laboratory strain PAO1. In this study, we investigated whether DEA-C3D disperses biofilms formed by clinical cystic fibrosis (CF) isolates of P. aeruginosa and its effect in combination with two antipseudomonal antibiotics, tobramycin and colistin, in vitro. Methods β-Lactamase-triggered release of NO from DEA-C3D was confirmed using a gas-phase chemiluminescence detector. MICs for P. aeruginosa clinical isolates were determined using the broth microdilution method. A crystal violet staining technique and confocal laser scanning microscopy were used to evaluate the effects of DEA-C3D on P. aeruginosa biofilms alone and in combination with tobramycin and colistin. Results DEA-C3D was confirmed to selectively release NO in response to contact with bacterial β-lactamase. Despite lacking direct, cephalosporin/β-lactam-based antibacterial activity, DEA-C3D was able to disperse biofilms formed by three P. aeruginosa clinical isolates. Confocal microscopy revealed that DEA-C3D in combination with tobramycin produces similar reductions in biofilm to DEA-C3D alone, whereas the combination with colistin causes near complete eradication of P. aeruginosa biofilms in vitro. Conclusions DEA-C3D is effective in dispersing biofilms formed by multiple clinical isolates of P. aeruginosa and could hold promise as a new adjunctive therapy to patients with CF.

scholarly journals Use of electromagnetic stimulation on an Enterococcus faecalis biofilm on root canal treated teeth in vitro

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Beatriz H. D. Panariello ◽  
Justin K. Kindler ◽  
Kenneth J. Spolnik ◽  
Ygal Ehrlich ◽  
George J. Eckert ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Root Canal ◽  
Laser Scanning ◽  
Confocal Imaging ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Microscopy Imaging ◽  
Electromagnetic Stimulation ◽  
Root Canal Disinfection

AbstractRoot canal disinfection is of utmost importance in the success of the treatment, thus, a novel method for achieving root canal disinfection by electromagnetic waves, creating a synergistic reaction via electric and thermal energy, was created. To study electromagnetic stimulation (EMS) for the disinfection of root canal in vitro, single rooted teeth were instrumented with a 45.05 Wave One Gold reciprocating file. Specimens were sterilized and inoculated with Enterococcus faecalis ATCC 29,212, which grew for 15 days to form an established biofilm. Samples were treated with 6% sodium hypochlorite (NaOCl), 1.5% NaOCl 1.5% NaOCl with EMS, 0.9% saline with EMS or 0.9% saline. After treatments, the colony forming units (CFU) was determined. Data was analyzed by Wilcoxon Rank Sums Test (α = 0.05). One sample per group was scored and split for confocal laser scanning microscopy imaging. There was a significant effect with the use of NaOCl with or without EMS versus 0.9% saline with or without EMS (p = 0.012 and 0.003, respectively). CFUs were lower when using 0.9% saline with EMS versus 0.9% saline alone (p = 0.002). Confocal imaging confirmed CFU findings. EMS with saline has an antibiofilm effect against E. faecalis and can potentially be applied for endodontic disinfection.

scholarly journals Cocktail of carbohydrases from Aspergillus niger: an economical and eco-friendly option for biofilm clearance from biopolymer surfaces

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Arashdeep Kaur ◽  
Sanjeev Kumar Soni ◽  
Shania Vij ◽  
Praveen Rishi
Keyword(s):  
Aspergillus Niger ◽  
Laser Scanning ◽  
Statistical Modelling ◽  
Laser Scanning Microscopy ◽  
Enzyme Treatment ◽  
Confocal Laser ◽  
Abiotic Surfaces ◽  
Enzyme Cocktail ◽  
Natural Variant

AbstractBiofilm formation on both biotic and abiotic surfaces accounts for a major factor in spread of antimicrobial resistance. Due to their ubiquitous nature, biofilms are of great concern for environment as well as human health. In the present study, an integrated process for the co-production of a cocktail of carbohydrases from a natural variant of Aspergillus niger was designed. The enzyme cocktail was found to have a noteworthy potential to eradicate/disperse the biofilms of selected pathogens. For application of enzymes as an antibiofilm agent, the enzyme productivities were enhanced by statistical modelling using response surface methodology (RSM). The antibiofilm potential of the enzyme cocktail was studied in terms of (i) in vitro cell dispersal assay (ii) release of reducing sugars from the biofilm polysaccharides (iii) the effect of enzyme treatment on biofilm cells and architecture by confocal laser scanning microscopy (CLSM). Potential of the enzyme cocktail to disrupt/disperse the biofilm of selected pathogens from biopolymer surfaces was also assessed by field emission scanning electron microscopy (FESEM) analysis. Further, their usage in conjunction with antibiotics was assessed and it was inferred from the results that the use of enzyme cocktail augmented the efficacy of the antibiotics. The study thus provides promising insights into the prospect of using multiple carbohydrases for management of heterogeneous biofilms formed in natural and clinical settings.

scholarly journals pH and Reduction Dual-Responsive Bi-Drugs Conjugated Dextran Assemblies for Combination Chemotherapy and In Vitro Evaluation

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1515
Author(s):  
Xiukun Xue ◽  
Yanjuan Wu ◽  
Xiao Xu ◽  
Ben Xu ◽  
Zhaowei Chen ◽  
...  
Keyword(s):  
Combination Chemotherapy ◽  
Laser Scanning ◽  
Rational Design ◽  
A549 Cells ◽  
Chemotherapeutic Agents ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Tumor Resistance ◽  
Oxidized Dextran

Polymeric prodrugs, synthesized by conjugating chemotherapeutic agents to functional polymers, have been extensively investigated and employed for safer and more efficacious cancer therapy. By rational design, a pH and reduction dual-sensitive dextran-di-drugs conjugate (oDex-g-Pt+DOX) was synthesized by the covalent conjugation of Pt (IV) prodrug and doxorubicin (DOX) to an oxidized dextran (oDex). Pt (IV) prodrug and DOX were linked by the versatile efficient esterification reactions and Schiff base reaction, respectively. oDex-g-Pt+DOX could self-assemble into nanoparticles with an average diameter at around 180 nm. The acidic and reductive (GSH) environment induced degradation and drug release behavior of the resulting nanoparticles (oDex-g-Pt+DOX NPs) were systematically investigated by optical experiment, DLS analysis, TEM measurement, and in vitro drugs release experiment. Effective cellular uptake of the oDex-g-Pt+DOX NPs was identified by the human cervical carcinoma HeLa cells via confocal laser scanning microscopy. Furthermore, oDex-g-Pt+DOX NPs displayed a comparable antiproliferative activity than the simple combination of free cisplatin and DOX (Cis+DOX) as the extension of time. More importantly, oDex-g-Pt+DOX NPs exhibited remarkable reversal ability of tumor resistance compared to the cisplatin in cisplatin-resistant lung carcinoma A549 cells. Take advantage of the acidic and reductive microenvironment of tumors, this smart polymer-dual-drugs conjugate could serve as a promising and effective nanomedicine for combination chemotherapy.

scholarly journals PGC-1-Related Coactivator, a Novel, Serum-Inducible Coactivator of Nuclear Respiratory Factor 1-Dependent Transcription in Mammalian Cells

2001 ◽  
Vol 21 (11) ◽  
pp. 3738-3749 ◽  
Author(s):  
Ulf Andersson ◽  
Richard C. Scarpulla
Keyword(s):  
Transcriptional Activation ◽  
Mammalian Cells ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Peroxisome Proliferator ◽  
Nuclear Respiratory Factor ◽  
Nuclear Respiratory Factor 1 ◽  
Cell Extracts

ABSTRACT The thermogenic peroxisome proliferator-activated receptor γ (PPAR-γ) coactivator 1 (PGC-1) has previously been shown to activate mitochondrial biogenesis in part through a direct interaction with nuclear respiratory factor 1 (NRF-1). In order to identify related coactivators that act through NRF-1, we searched the databases for sequences with similarities to PGC-1. Here, we describe the first characterization of a 177-kDa transcriptional coactivator, designated PGC-1-related coactivator (PRC). PRC is ubiquitously expressed in murine and human tissues and cell lines; but unlike PGC-1, PRC was not dramatically up-regulated during thermogenesis in brown fat. However, its expression was down-regulated in quiescent BALB/3T3 cells and was rapidly induced by reintroduction of serum, conditions where PGC-1 was not detected. PRC activated NRF-1-dependent promoters in a manner similar to that observed for PGC-1. Moreover, NRF-1 was immunoprecipitated from cell extracts by antibodies directed against PRC, and both proteins were colocalized to the nucleoplasm by confocal laser scanning microscopy. PRC interacts in vitro with the NRF-1 DNA binding domain through two distinct recognition motifs that are separated by an unstructured proline-rich region. PRC also contains a potent transcriptional activation domain in its amino terminus adjacent to an LXXLL motif. The spatial arrangement of these functional domains coincides with those found in PGC-1, supporting the conclusion that PRC and PGC-1 are structurally and functionally related. We conclude that PRC is a functional relative of PGC-1 that operates through NRF-1 and possibly other activators in response to proliferative signals.

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