Advances in aPDT based on the combination of a porphyrinic formulation with potassium iodide: Effectiveness on bacteria and fungi planktonic/biofilm forms and viruses

2019 ◽  
Vol 23 (04n05) ◽  
pp. 534-545 ◽  
Author(s):  
Cátia Vieira ◽  
Adriele Santos ◽  
Mariana Q. Mesquita ◽  
Ana T. P. C. Gomes ◽  
M. Graça P. M. S. Neves ◽  
...  
Keyword(s):  
Treatment Time ◽  
Low Cost ◽  
Alternative Methods ◽  
Gram Positive ◽  
Gram Negative ◽  
Potentiation Effect ◽  
Low Concentrations ◽  
Form Alone ◽  
Planktonic Form ◽  
Bacteria And Fungi

The increasing world-wide rate of antibiotic resistance as well as the capacity of microorganisms to form biofilms, have led to a higher incidence of mortal infections that require alternative methods for their control. Antimicrobial photodynamic therapy (aPDT) emerged as an effective solution against resistant strains. The present work aims to evaluate the aPDT efficiency of a photosensitizer (PS) based on a low-cost formulation constituted by five cationic porphyrins (FORM) and its potentiation effect by KI on a broad spectrum of microorganisms under white light (380–700 nm, 25 W/m[Formula: see text]. The aPDT assays were performed with different concentrations of FORM (0.1 to 5.0 [Formula: see text]M) and 100 mM of KI on planktonic and biofilm forms of gram-positive (methicillin resistant Staphylococcus aureus–MRSA) and gram-negative (Escherichia coli resistant to chloramphenicol and ampicillin) bacteria, of the fungi Candida albicans and on a T4-like bacteriophage as a mammalian virus model. The results indicate that the FORM alone is an efficient PS to photoinactivate not only gram-negative and gram-positive bacteria, but also C. albicans, in planktonic and biofilm forms, and T4-like phage at low concentrations (<5.0 [Formula: see text]M). The presence of KI enhanced the photodynamic effect of this FORM for all microorganisms on the planktonic form, allowing the reduction of PS concentration and treatment time. The results also show that the combination FORM/KI is highly efficient in the elimination of already well-established biofilms of E. coli,S. aureus and C. albicans. This effect is probably associated with longer-lived iodine reactive species produced during the aPDT treatment.

Serum biomarkers to differentiate Gram-negative, Gram-positive and fungal infection in febrile patients

2021 ◽  
Vol 70 (7) ◽  
Author(s):  
Dongguang Niu ◽  
Qian Huang ◽  
Fan Yang ◽  
Weiliang Tian ◽  
Chen Li ◽  
...  
Keyword(s):  
Bloodstream Infection ◽  
Bacterial Infections ◽  
Fungal Infections ◽  
Serum Levels ◽  
Serum Biomarker ◽  
Diagnostic Efficiency ◽  
Gram Positive ◽  
Gram Negative ◽  
Neutrophil Lymphocyte Ratio ◽  
Bacteria And Fungi

Introduction. Contamination of specimens and overuse of broad spectrum antibiotics contribute to false positives and false negatives, respectively. Therefore, useful and applicable biomarkers of bacteremia are still required. Hypothesis/Gap Statement. IL-6 can be used as a serum biomarker to discriminate among bacterial infections and fungal infections in febrile patients with a bloodstream infection. Aim. We aimed to evaluate the diagnostic efficiency of neutrophil/lymphocyte ratio (NLR), procalcitonin (PCT) and interleukin-6 (IL-6) in discriminating Gram-negative (G−) bacteria from Gram-positive (G+) bacteria and fungi in febrile patients. Methodology. A total of 567 patients with fever were evaluated. Serum levels of IL-6, PCT, NLR and CRP were compared among a G− group (n=188), a G+ group (n=168), a fungal group (n=38) and a culture negative group (n=173). Sensitivity, specificity, Yuden’s index and area under the Receiver operating characteristic (ROC) curve (AUC) were obtained to analyse the diagnostic abilities of these biomarkers in discriminating bloodstream infection caused by different pathogens. Results. Serum IL-6 and PCT in the G− group increased significantly when compared with both the G+ group and fungal group (P <0.05). AUC of IL-6 (0.767, 95 % CI:0.725–0.805) is higher than AUC of PCT (0.751, 95 % CI:0.708–0.796) in discriminating the G− group from G+ group. When discriminating the G− group from fungal group, the AUC of IL-6 (0.695, 95 % CI:0.651–0.747) with a cut-off value of 464.3 pg ml−1 was also higher than the AUC of PCT (0.630, 95 % CI:0.585–0.688) with a cut-off value of 0.68 ng ml−1. Additionally, AUC of NLR (0.685, 95 % CI:0.646–0.727) in discriminating the fungal group from G+ group at the cut-off value of 9.03, was higher than AUC of IL-6, PCT and CRP. Conclusion. This study suggests that IL-6 could be used as a serum biomarker to discriminate among bacterial infections and fungal infections in febrile patients with a bloodstream infection. In addition, NLR is valuable to discriminate fungal infections from Gram-positive infections in febrile patients with a bloodstream infection.

Utility of 3-(thiophen-2-yl)prop-2-enoyl isothiocyanate in heterocyclic synthesis

2019 ◽  
Vol 43 (9-10) ◽  
pp. 307-312
Author(s):  
Amira A El-Sayed ◽  
Saad R Atta-Allah ◽  
Magdy M Hemdan
Keyword(s):  
Antibacterial Activity ◽  
Spectral Data ◽  
Gram Negative Bacteria ◽  
Heterocyclic Synthesis ◽  
Gram Positive ◽  
Thiourea Derivatives ◽  
Gram Negative ◽  
Bacteria And Fungi

Convenient syntheses of quinazoline, benzothiazole, thiadiazole, imidazole, and thiourea derivatives starting from 3-(thiophen-2-yl)prop-2-enoyl isothiocyanate are described. The structures of the synthesized compounds are confirmed from their microanalytical and spectral data. Some of the products are examined for their antibacterial activity against Gram-positive and Gram-negative bacteria and fungi.

Rifampicin

1970 ◽  
Vol 8 (3) ◽  
pp. 11-12
Keyword(s):  
Messenger Rna ◽  
Viral Infections ◽  
Drug Resistant ◽  
Gram Positive ◽  
Gram Negative ◽  
Low Concentrations ◽  
Resistant Mutants ◽  
Gram Negative Organisms

Rifampicin (Rifadin-Lepetit; Rimactane-Ciba) is a semi-synthetic antibiotic derived from Streptomyces mediterranei which inhibits the synthesis of bacterial messenger-RNA. In vitro it is active against Gram-positive organisms and mycobacteria in low concentrations (0.0002 – 0.5 mcg/ml); and against Gram-negative organisms in higher concentrations (1 – 10 mcg/ml). Drug-resistant mutants readily emerge if rifampicin is used alone.1 It is already established as an important agent in the treatment of tuberculosis. Its usefulness in other bacterial and in viral infections is uncertain.

Environmentally benign one-pot synthesis and antimicrobial activity of 1-methyl-2,6-diarylpiperidin-4-ones

2011 ◽  
Vol 65 (5) ◽  
Author(s):  
Pattusamy Nithya ◽  
Fazlur-Rahman Nawaz Khan ◽  
Selvaraj Roopan ◽  
Uma Shankar ◽  
Jong Jin
Keyword(s):  
Antimicrobial Activity ◽  
Environmentally Benign ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
One Pot ◽  
Gram Negative ◽  
One Pot Synthesis ◽  
Bacteria And Fungi

AbstractAn efficient and environmentally benign one-pot method for the synthesis of 1-methyl-2,6-diarylpiperidin-4-ones using montmorillonite K-10 as a catalyst has been developed. Antimicrobial activity of the compounds has been tested against selected representatives of Gram-positive and Gram-negative bacteria and fungi.

scholarly journals Synthesis, antioxidant and antimicrobial activity of carbohydrazones

2017 ◽  
Vol 82 (5) ◽  
pp. 495-508 ◽  
Author(s):  
Aleksandra Bozic ◽  
Nenad Filipovic ◽  
Irena Novakovic ◽  
Snezana Bjelogrlic ◽  
Jasmina Nikolic ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antioxidant Activity ◽  
Dimethyl Sulphoxide ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Gram Negative ◽  
Antioxidant Compound ◽  
Antioxidant And Antimicrobial Activity ◽  
Bacteria And Fungi

Fourteen mono- and bis-carbohydrazone ligands have been synthesized and characterized. Antioxidant activity of the substances was investigated together with possible (E)/(Z) isomerization, and explained on the most active antioxidant compound 4 in various dimethyl sulphoxide?water mixtures. The addition of water to the system was involved in the formation of hydrated molecules which was confirmed in NMR after the addition of D2O. The ligands were tested in vitro against Gram-positive and Gram-negative bacteria and fungi, and their activity was discussed in relation to the structure of investigated carbohydrazone.

scholarly journals Synthesis, Antibacterial and Antifungal Properties of Cyclohexane Tosyloxyimine Derivative

2019 ◽  
Vol 4 (3) ◽  
pp. 1-4
Author(s):  
Shoaib M
Keyword(s):  
Antimicrobial Agents ◽  
Sulfonyl Chloride ◽  
Antimicrobial Properties ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Bacteria And Fungi ◽  
Agar Well Diffusion Assay ◽  
Antibacterial And Antifungal ◽  
Candida Pseudotropicalis

Due to increasing antimicrobial resistance, functionally substituted cyclohexane derivatives are being explored as potential antimicrobial agents. Reaction of diethyl 4 - hydroxy - 6 - (hyd - roxyimino) - 4 - methyl - 2 - phenylcyclohexane - 1,3 - dicarboxylate with 4 - toluene sulfonyl chloride in boiling acetone in the presence of equimolar triethylamine resulted in formation of diethyl - 4 - hydroxy - 4 - methyl - 2 - phenyl - 6 - ((tosyloxy)imino) cyclohexane - 1,3 - dicarboxylate. The structure of novel compound was characterized by 1 H and 13 C NMR spectra and elemental analysis was performed. Agar well diffusion assay was used to screen novel compound against Gram - positive bacteria, Gram - negative bacteria and fungi. Test compound showed better antimicrobial properties against Gram - negative bac teria as compared to Gram - positive bacteria and fungi. Acinetobacter baumannii BDU - 32 was found to be most sensitive bacteria while Candida pseudotropicalis BDU MA88 was found to be most sensitive yeast.

scholarly journals Antimicrobial Biophotonic Treatment of Ampicillin-Resistant Pseudomonas aeruginosa with Hypericin and Ampicillin Cotreatment Followed by Orange Light

Pharmaceutics ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 641 ◽  
Author(s):  
Seemi Tasnim Alam ◽  
Tram Anh Ngoc Le ◽  
Jin-Soo Park ◽  
Hak Cheol Kwon ◽  
Kyungsu Kang
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Cell Wall ◽  
Gram Positive ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Wall Structures ◽  
Global Issue ◽  
Life Threatening ◽  
Bacteria And Fungi

Bacterial antibiotic resistance is an alarming global issue that requires alternative antimicrobial methods to which there is no resistance. Antimicrobial photodynamic therapy (APDT) is a well-known method to combat this problem for many pathogens, especially Gram-positive bacteria and fungi. Hypericin and orange light APDT efficiently kill Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and the yeast Candida albicans. Although Gram-positive bacteria and many fungi are readily killed with APDT, Gram-negative bacteria are difficult to kill due to their different cell wall structures. Pseudomonas aeruginosa is one of the most important opportunistic, life-threatening Gram-negative pathogens. However, it cannot be killed successfully by hypericin and orange light APDT. P. aeruginosa is ampicillin resistant, but we hypothesized that ampicillin could still damage the cell wall, which can promote photosensitizer uptake into Gram-negative cells. Using hypericin and ampicillin cotreatment followed by orange light, a significant reduction (3.4 log) in P. aeruginosa PAO1 was achieved. P. aeruginosa PAO1 inactivation and gut permeability improvement by APDT were successfully shown in a Caenorhabditis elegans model.

scholarly journals Synthesis of certain pyrrole derivatives as antimicro-bial agents

2009 ◽  
Vol 59 (2) ◽  
pp. 145-158 ◽  
Author(s):  
Mosaad Mohamed ◽  
Ramdan El-Domany ◽  
Rania Abd El-Hameed
Keyword(s):  
Antimicrobial Activity ◽  
Aromatic Amines ◽  
Gram Negative Bacteria ◽  
Gram Positive ◽  
Pyrrole Derivatives ◽  
Gram Negative ◽  
Primary Aromatic Amines ◽  
Aryl Amines ◽  
Bacteria And Fungi

Synthesis of certain pyrrole derivatives as antimicro-bial agentsIn an effort to establish new pyrroles and pyrrolo[2,3-d] pyrimidines with improved antimicrobial activity we report here the synthesis andin vitromicrobiological evaluation of a series of pyrrole derivatives. A series of new 2-aminopyrrole-3-carbonitriles (1a-d) were synthesized from the reaction of benzoin, primary aromatic amines and malononitrile, from which a number of pyrrole derivatives (2a-dto5a-d) and pyrrolo[2,3-d]pyrimidines (6a-dto10a, d) were synthesized. Thein vitroantimicrobial testing of the synthesized compounds was carried out against Gram-positive, Gram-negative bacteria and fungi. Some of the prepared compounds, [2-amino-1-(2-methylphenyl)-4,5-diphenyl-1H-pyrrole-3-carbonitriles (1b), 2-amino-3-carbamoyl-1-(3-methylphenyl)-4,5-diphenyl-1H-pyrroles (2b),N-(3-cyano-1-(2-methylphenyl)-4,5-diphenyl-1H-pyrrol-2-yl)-acetamides (3b),N-(3-cyano-1-(3-methylphenyl)-4,5-diphenyl-1H-pyrrol-2-yl)-acetamides (3c), 2-amino-1-(4-methoxyphenyl)-4,5-diphenyl-3-tetrazolo-1H-pyrroles (5d),7-(4-methoxyphenyl)-5,6-diphenyl-7H-pyrrolo [2,3-d]pyrimidin-4(3H)-ones (7d), 7-(3-methylphenyl)-5,6-diphenyl-7H-pyrrolo[2,3-d]pyrimidin-4(3H)-thione (9b) andN-(7-(2-methylphenyl)-5,6-diphenyl-7H-pyrrolo[2,3-d] pyrimidine)-N-aryl amines (10a)] showed potent antimicrobial activity.

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