scholarly journals Nonselective Mevalonate Kinase Inhibitor as a Novel Class of Antibacterial Agents

Cholesterol ◽  
2015 ◽  
Vol 2015 ◽  
pp. 1-3 ◽  
Author(s):  
Mohammad Gharehbeglou ◽  
Ghasem Arjmand ◽  
Mohammad Reza Haeri ◽  
Mohammad Khazeni
Keyword(s):  
Cell Wall ◽  
Bacterial Resistance ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Dilution Method ◽  
Mevalonate Kinase ◽  
E Coli ◽  
New Antibiotics ◽  
Serial Dilution Method ◽  
Cell Wall Inhibition

Introduction. There are a few evidences about targeting isoprenoids biosynthesis pathway in bacteria for finding new antibiotics. This study was conducted to assess antibacterial effects of vanadyl sulfate (VS), one of the mevalonate kinase inhibitors to find a new target for killing bacteria. Materials and Methods. Antibacterial effect of VS alone and in combination with glycine or EDTA was assessed on Escherichia coli and Pseudomonas aeruginosa as Gram-negative and Staphylococcus aureus and Enterococcus faecalis as Gram-positive bacteria using serial dilution method and minimum inhibitory concentrations (MICs) identified. Result. MICs for S. aureus and E. coli were 4 and 8 mg/mL, respectively. VS could not affect the growth of two other bacteria. However, VS in combination with glycine not only inhibited the growth of E. faecalis and P. aeruginosa, but also reduced MICs for VS-sensitive bacteria (S. aureus and E. coli). EDTA could reduce MIC for E. coli and P. aeruginosa. Conclusion. VS could inhibit the growth of S. aurous and E. coli, and adding glycine or EDTA improved VS antibacterial activity presumably via instability of the cell wall and enhanced transport of VS through bacterial cell wall. Inhibition of the isoprenoid pathway might provide new tools to overcome bacterial resistance.

Phyto-Assisted Synthesis and Characterization of V2O5 Nanomaterial and their Electrochemical and Antimicrobial Investigations

Nano LIFE ◽  
2020 ◽  
Vol 10 (03) ◽  
pp. 2050003 ◽  
Author(s):  
Sonali Gautam ◽  
Anuj Kumar ◽  
Vinod Kumar Vashistha ◽  
Deepak Kumar Das
Keyword(s):  
Antimicrobial Activity ◽  
Dilution Method ◽  
Standard Drug ◽  
E Coli ◽  
Serial Dilution Method ◽  
Voltammetric Studies ◽  
Li Ion ◽  
Cyclic Voltammetric Studies ◽  
Neem Leaf Extract

The chemical and physical synthetic strategies for the preparation of nanomaterials are time-consuming, costly and toxic. To address these issues, Phyto-assisted synthesis of nanomaterials can be considered as a promising strategy. Herein, V2O5 nanomaterial has been synthesized by using Azadirachta indica (Neem) leaf extract. The V2O5 nanomaterial was characterized by employing multiple techniques, such as UV-Vis, FTIR, XRD, FE-SEM and EDX. The results showed that V2O5 nanomaterial possesses nanoplate’s type morphology with 30–50[Formula: see text]nm diameters. Further, cyclic voltammetric studies showed the good durability during the voltammetric scans in 2M KCl electrolyte at 50[Formula: see text]mV/s scan rate and the V2O5 nanoplates may be served as a promising cathodic candidate in Li-ion secondary batteries. Moreover, the antimicrobial activity of the prepared V2O5 nanoplates was evaluated against the bacteria viz. S. typhi, S. aureus, B. subtilis, E. coli and fungi; F. species, A. flavus, P. triticina and A. niger by using the serial dilution method. The results suggested that V2O5 nanoplates possess comparable antimicrobial activity comparable to standard drug Streptomycin against the used pathogens.

scholarly journals Teeth Whitening and Antibacterial Effects of Juglans regia Bark: A Preliminary Study

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Riham Al-Rawi ◽  
Yusra Bashir ◽  
Aseel Mustafa ◽  
Mennatalla Omar ◽  
Noor AL-Rawi ◽  
...  
Keyword(s):  
Inhibitory Concentration ◽  
Juglans Regia ◽  
Ethanol Extract ◽  
Dilution Method ◽  
Antimicrobial Effects ◽  
E Coli ◽  
The Past ◽  
Serial Dilution Method ◽  
Preliminary Study

Objectives. Natural folk medicines with antimicrobial effects have been under investigation during the past decades. The aim of this study was to evaluate the teeth whitening and antimicrobial effects of ethanol extract of Persian walnut “Juglans regia” barks. Materials and Methods. Minimum inhibitory concentration (MIC) was determined using a broth microdilution assay which was conducted through a 2-fold serial dilution method, and a whitening experiment was done in vitro on extracted teeth, with a pH test being performed on 2-fold dilutions of the ethanol extract. Result. It was found that the MIC for Enterobacter and E. coli and Staphylococcus and Pseudomonas was found to be 5 mg/ml and 2.5 mg/ml, respectively. Both dilutions were found to be acidic, and the extract of Juglans regia bark also demonstrated the ability of teeth whitening. Conclusion. This study supports the use of Juglans regia bark as a natural product in dentistry because of the confirmed antimicrobial ability as well as its whitening effect. Clinical Relevance. Herb extract might be incorporated within commercially available kinds of toothpaste to enhance its whitening and antimicrobial effects.

Sites of Adsorption of the Bacteriophages T3 and T5 on the Wall of Escherichia Coli B.

1967 ◽  
Vol 25 ◽  
pp. 96-97
Author(s):  
Manfred E. Bayer
Keyword(s):  
Escherichia Coli ◽  
Cell Wall ◽  
Electron Microscope ◽  
Uranyl Acetate ◽  
E Coli ◽  
Receptor Sites ◽  
Rigid Cell Wall ◽  
Host Cell Surface ◽  
Bacterial Viruses ◽  
Escherichia Coli B

Bacterial viruses adsorb specifically to receptors on the host cell surface. Although the chemical composition of some of the cell wall receptors for bacteriophages of the T-series has been described and the number of receptor sites has been estimated to be 150 to 300 per E. coli cell, the localization of the sites on the bacterial wall has been unknown.When logarithmically growing cells of E. coli are transferred into a medium containing 20% sucrose, the cells plasmolize: the protoplast shrinks and becomes separated from the somewhat rigid cell wall. When these cells are fixed in 8% Formaldehyde, post-fixed in OsO4/uranyl acetate, embedded in Vestopal W, then cut in an ultramicrotome and observed with the electron microscope, the separation of protoplast and wall becomes clearly visible, (Fig. 1, 2). At a number of locations however, the protoplasmic membrane adheres to the wall even under the considerable pull of the shrinking protoplast. Thus numerous connecting bridges are maintained between protoplast and cell wall. Estimations of the total number of such wall/membrane associations yield a number of about 300 per cell.

scholarly journals Thrombotic microangiopathy in dasatinib-treated patients with chronic myeloid leukemia

2019 ◽  
Vol 4 (1-2) ◽  
pp. 41-45 ◽  
Author(s):  
Takeo Koshida ◽  
Sylvia Wu ◽  
Hitoshi Suzuki ◽  
Rimda Wanchoo ◽  
Vanesa Bijol ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Tyrosine Kinase ◽  
Tyrosine Kinase Inhibitor ◽  
Tyrosine Kinase Inhibitors ◽  
Thrombotic Microangiopathy ◽  
Myeloid Leukemia ◽  
Kinase Inhibitors ◽  
Kidney Biopsy ◽  
Kinase Inhibitor ◽  
Target Effect

Dasatinib is the second-generation tyrosine kinase inhibitor used in the treatment of chronic myeloid leukemia. Proteinuria has been reported with this agent. We describe two kidney biopsy–proven cases of dasatinib-induced thrombotic microangiopathy that responded to stoppage of dasatinib and using an alternate tyrosine kinase inhibitor. Certain specific tyrosine kinase inhibitors lead to endothelial injury and renal-limited thrombotic microangiopathy. Hematologists and nephrologists need to be familiar with this off-target effect of dasatinib.

scholarly journals Computational evaluation of potent 2-(1H-imidazol-2-yl) pyridine derivatives as potential V600E-BRAF inhibitors

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Abdullahi Bello Umar ◽  
Adamu Uzairu ◽  
Gideon Adamu Shallangwa ◽  
Sani Uba
Keyword(s):  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Acquired Resistance ◽  
Docking Studies ◽  
Major Protein ◽  
Pharmacological Properties ◽  
Braf Inhibitors ◽  
Protein Target ◽  
Computational Evaluation ◽  
Better Than

Abstract Background V600E-BRAF is a major protein target involved in various types of human cancers. However, the acquired resistance of the V600E-BRAF kinase to the vemurafenib and the side effects of other identified drugs initiate the search for efficient inhibitors. In the current paper, virtual docking screening combined with drug likeness and ADMET properties predictions were jointly applied to evaluate potent 2-(1H-imidazol-2-yl) pyridines as V600E-BRAF kinase inhibitors. Results Most of the studied compounds showed better docking scores and favorable interactions with theiV600E-BRAF target. Among the screened compounds, the two most potent (14 and 30) with good rerank scores (−124.079 and − 122.290) emerged as the most effective, and potent V600E-BRAF kinase inhibitors which performed better than vemurafenib (−116.174), an approved V600E-BRAF kinase inhibitor. Thus, the docking studies exhibited that these compounds have shown competing inhibition of V600E-BRAF kinase with vemurafenib at the active site and revealed better pharmacological properties based on Lipinski’s and Veber’s drug-likeness rules for oral bioavailability and ADMET properties. Conclusion The docking result, drug-likeness rules, and ADMET parameters identified compounds (14 and 30) as the best hits against V600E-BRAF kinase with better pharmacological properties. This suggests that these compounds may be developed as potent V600E-BRAF inhibitors.

scholarly journals Distinct Effects of Escherichia coli,Pseudomonas aeruginosa and Staphylococcus aureus Cell Wall Component-Induced Inflammation on the Iron Metabolism of THP-1 Cells

2021 ◽  
Vol 22 (3) ◽  
pp. 1497
Author(s):  
Edina Pandur ◽  
Kitti Tamási ◽  
Ramóna Pap ◽  
Gergely Jánosa ◽  
Katalin Sipos
Keyword(s):  
Cell Wall ◽  
Inflammatory Cytokines ◽  
Iron Metabolism ◽  
Inflammatory Cytokine ◽  
Cytokine Production ◽  
Storage Proteins ◽  
Iron Storage ◽  
E Coli ◽  
Iron Storage Proteins ◽  
Pro Inflammatory Cytokines

Macrophages are essential immune cells of the innate immune system. They participate in the development and regulation of inflammation. Macrophages play a fundamental role in fighting against bacterial infections by phagocytosis of bacteria, and they also have a specific role in immunomodulation by secreting pro-inflammatory cytokines. In bacterial infection, macrophages decrease the serum iron concentration by removing iron from the blood, acting as one of the most important regulatory cells of iron homeostasis. We examined whether the Gram-positive and Gram-negative cell wall components from various bacterial strains affect the cytokine production and iron transport, storage and utilization of THP-1 monocytes in different ways. We found that S. aureus lipoteichoic acid (LTA) was less effective in activating pro-inflammatory cytokine expression that may related to its effect on fractalkine production. LTA-treated cells increased iron uptake through divalent metal transporter-1, but did not elevate the expression of cytosolic and mitochondrial iron storage proteins, suggesting that the cells maintained iron efflux via the ferroportin iron exporter. E. coli and P. aeruginosa lipopolysaccharides (LPSs) acted similarly on THP-1 cells, but the rates of the alterations of the examined proteins were different. E. coli LPS was more effective in increasing the pro-inflammatory cytokine production, meanwhile it caused less dramatic alterations in iron metabolism. P. aeruginosa LPS-treated cells produced a smaller amount of pro-inflammatory cytokines, but caused remarkable elevation of both cytosolic and mitochondrial iron storage proteins and intracellular iron content compared to E. coli LPS. These results prove that LPS molecules from different bacterial sources alter diverse molecular mechanisms in macrophages that prepossess the outcome of the bacterial infection.

scholarly journals Evaluation of the Antimicrobial Activity of Some Components of the Essential Oils of Plants Used in the Traditional Medicine of the Tehuacán-Cuicatlán Valley, Puebla, México

Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 295
Author(s):  
Sebastián Candelaria-Dueñas ◽  
Rocío Serrano-Parrales ◽  
Marisol Ávila-Romero ◽  
Samuel Meraz-Martínez ◽  
Julieta Orozco-Martínez ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Essential Oils ◽  
Qualitative Evaluation ◽  
Bactericidal Effect ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Diffusion Technique ◽  
Agar Dilution

In Tehuacán-Cuicatlán valley (Mexico), studies have been carried out on the essential oils of medicinal plants with antimicrobial activity and it was found that they present compounds in common such as: α-pinene, β-pinene, carvacrol, eugenol, limonene, myrcene, ocimene, cineole, methyl salicylate, farnesene, and thymol. The goal of this study was to assess the antimicrobial activity of essential oils’ compounds. The qualitative evaluation was carried out by the Kirby Baüer agar diffusion technique in Gram-positive bacteria (11 strains), Gram-negative bacteria (18 strains), and yeasts (8 strains). For the determination of the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), the agar dilution method was used. All the evaluated compounds presented antimicrobial activity. The compounds eugenol and carvacrol showed the largest inhibition zones. Regarding yeasts, the compounds ocimene, cineole, and farnesene did not show any activity. The compounds eugenol, carvacrol, and thymol presented the lowest MIC; bactericidal effect was observed at MIC level for S. aureus 75MR, E. coli 128 MR, and C albicans CUSI, for different compounds, eugenol, carvacrol, and thymol. Finally, this study shows that the essential oils of plants used by the population of Tehuacán-Cuicatlán valley share compounds and some of them have antibacterial and fungicidal activity.

scholarly journals Targeting USP47 overcomes tyrosine kinase inhibitor resistance and eradicates leukemia stem/progenitor cells in chronic myelogenous leukemia

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Hu Lei ◽  
Han-Zhang Xu ◽  
Hui-Zhuang Shan ◽  
Meng Liu ◽  
Ying Lu ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Progenitor Cells ◽  
Chronic Myelogenous Leukemia ◽  
Drug Targets ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Myelogenous Leukemia ◽  
Tki Resistance

AbstractIdentifying novel drug targets to overcome resistance to tyrosine kinase inhibitors (TKIs) and eradicating leukemia stem/progenitor cells are required for the treatment of chronic myelogenous leukemia (CML). Here, we show that ubiquitin-specific peptidase 47 (USP47) is a potential target to overcome TKI resistance. Functional analysis shows that USP47 knockdown represses proliferation of CML cells sensitive or resistant to imatinib in vitro and in vivo. The knockout of Usp47 significantly inhibits BCR-ABL and BCR-ABLT315I-induced CML in mice with the reduction of Lin−Sca1+c-Kit+ CML stem/progenitor cells. Mechanistic studies show that stabilizing Y-box binding protein 1 contributes to USP47-mediated DNA damage repair in CML cells. Inhibiting USP47 by P22077 exerts cytotoxicity to CML cells with or without TKI resistance in vitro and in vivo. Moreover, P22077 eliminates leukemia stem/progenitor cells in CML mice. Together, targeting USP47 is a promising strategy to overcome TKI resistance and eradicate leukemia stem/progenitor cells in CML.

scholarly journals A Facile Synthesis and Studies of Some New Chalcones and Their Derivatives Based on Heterocyclic Ring

2012 ◽  
Vol 9 (4) ◽  
pp. 1897-1905 ◽  
Author(s):  
A. Solankee ◽  
K. Patel ◽  
R. Patel
Keyword(s):  
Inhibitory Concentration ◽  
Guanidine Hydrochloride ◽  
Heterocyclic Ring ◽  
Dilution Method ◽  
Facile Synthesis ◽  
Phenyl Hydrazine ◽  
Gram Negative ◽  
E Coli ◽  
Heterocyclic Aldehydes ◽  
Broth Dilution

Chalcones(6a-f)have been prepared by the condensation of ketone(5)and different aromatic and heterocyclic aldehydes. These chalcones(6a-f)on treatment with guanidine hydrochloride and phenyl hydrazine hydrochloride in presence of alkali give aminopyrimidines(7a-f)and phenylpyrazolines(8a-f)respectively. All the newly synthesized compounds have been characterized on the basis of IR,1HNMR spectral data as well as physical data. Antibacterial activity (minimum inhibitory concentration MIC) against Gram-positiveS. aureusMTCC 96 andS. pyogeneusMTCC 442 and Gram-negativeP. aeruginosaMTCC 1688 andE. coliMTCC 443 bacteria, as well as antifungal acivities (MIC) againstC. albicansMTCC 227,A. nigerMTCC 282 andA. clavatusMTCC 1323 were determined by broth dilution method.

scholarly journals Independent Behavior of Commensal Flora for Carriage of Fluoroquinolone-Resistant Bacteria in Patients at Admission

2010 ◽  
Vol 54 (12) ◽  
pp. 5193-5200 ◽  
Author(s):  
Victoire de Lastours ◽  
Françoise Chau ◽  
Florence Tubach ◽  
Blandine Pasquet ◽  
Etienne Ruppé ◽  
...  
Keyword(s):  
Risk Factors ◽  
Bacterial Resistance ◽  
Care Facility ◽  
Health Care Facility ◽  
Epidemiological Data ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
E Coli ◽  
Commensal Flora ◽  
Resistant Strains

ABSTRACT The important role of commensal flora as a natural reservoir of bacterial resistance is now well established. However, whether the behavior of each commensal flora is similar to that of other floras in terms of rates of carriage and risk factors for bacterial resistance is unknown. During a 6-month period, we prospectively investigated colonization with fluoroquinolone-resistant bacteria in the three main commensal floras from hospitalized patients at admission, targeting Escherichia coli in the fecal flora, coagulase-negative Staphylococcus (CNS) in the nasal flora, and α-hemolytic streptococci in the pharyngeal flora. Resistant strains were detected on quinolone-containing selective agar. Clinical and epidemiological data were collected. A total of 555 patients were included. Carriage rates of resistance were 8.0% in E. coli, 30.3% in CNS for ciprofloxacin, and 27.2% in streptococci for levofloxacin; 56% of the patients carried resistance in at least one flora but only 0.9% simultaneously in all floras, which is no more than random. Risk factors associated with the carriage of fluoroquinolone-resistant strains differed between fecal E. coli (i.e., colonization by multidrug-resistant bacteria) and nasal CNS (i.e., age, coming from a health care facility, and previous antibiotic treatment with a fluoroquinolone) while no risk factors were identified for pharyngeal streptococci. Despite high rates of colonization with fluoroquinolone-resistant bacteria, each commensal flora behaved independently since simultaneous carriage of resistance in the three distinct floras was uncommon, and risk factors differed. Consequences of environmental selective pressures vary in each commensal flora according to its local specificities (clinical trial NCT00520715 [http://clinicaltrials.gov/ct2/show/NCT00520715 ]).

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