Broad Spectrum Antimicrobial Activity of Licochalcones A and E against MDR (Multidrug Resistant) Strains of Clinical Origin

The aim of this study was to evaluate the antibacterial activity of the licochalcones A (1) and E (2) against drug resistant strains of clinical origin. The results indicate that the licochalcones had a broad inhibitory activity against tested bacteria. Compared to vancomycin and teicoplanin, these compounds provided weaker activity against non-MDR Staphylococcus aureus and Enterococcus but broader activity against MRSA and VRE strains. The results provide promising baseline information for the potential use of 1 and 2 from Glycyrrhiza inflata in the treatment of drug resistant bacterial infections.

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Antimicrobial Contribution of Chitosan Surface-Modified Nanoliposomes Combined with Colistin against Sensitive and Colistin-Resistant Clinical Pseudomonas aeruginosa

Pharmaceutics ◽

10.3390/pharmaceutics13010041 ◽

2020 ◽

Vol 13 (1) ◽

pp. 41

Author(s):

Valentina Laverde-Rojas ◽

Yamil Liscano ◽

Sandra Patricia Rivera-Sánchez ◽

Ivan Darío Ocampo-Ibáñez ◽

Yeiston Betancourt ◽

...

Keyword(s):

Antimicrobial Activity ◽

Physicochemical Parameters ◽

Bacterial Infections ◽

Public Health Problem ◽

Md Simulations ◽

Multidrug Resistant ◽

Drug Resistant ◽

Resistant Strains ◽

Surface Modified ◽

Antibiotic Peptide

Colistin is a re-emergent antibiotic peptide used as a last resort in clinical practice to overcome multi-drug resistant (MDR) Gram-negative bacterial infections. Unfortunately, the dissemination of colistin-resistant strains has increased in recent years and is considered a public health problem worldwide. Strategies to reduce resistance to antibiotics such as nanotechnology have been applied successfully. In this work, colistin was characterized physicochemically by surface tension measurements. Subsequently, nanoliposomes coated with highly deacetylated chitosan were prepared with and without colistin. The nanoliposomes were characterized using dynamic light scattering and zeta potential measurements. Both physicochemical parameters fluctuated relatively to the addition of colistin and/or polymer. The antimicrobial activity of formulations increased by four-fold against clinical isolates of susceptible Pseudomona aeruginosa but did not have antimicrobial activity against multidrug-resistant (MDR) bacteria. Interestingly, the free coated nanoliposomes exhibited the same antibacterial activity in both sensitive and MDR strains. Finally, the interaction of colistin with phospholipids was characterized using molecular dynamics (MD) simulations and determined that colistin is weakly associated with micelles constituted by zwitterionic phospholipids.

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Essential Oils and Non-volatile Compounds Derived from Chamaecyparis obtusa: Broad Spectrum Antimicrobial Activity against Infectious Bacteria and MDR(multidrug resistant) Strains

Natural Product Communications ◽

10.1177/1934578x1601100536 ◽

2016 ◽

Vol 11 (5) ◽

pp. 1934578X1601100 ◽

Cited By ~ 1

Author(s):

Min-Suk Bae ◽

Dae-Hun Park ◽

Chul-Yung Choi ◽

Gye-Yeop Kim ◽

Jin-Cheol Yoo ◽

...

Keyword(s):

Antimicrobial Activity ◽

Essential Oil ◽

Methicillin Resistant Staphylococcus Aureus ◽

Chamaecyparis Obtusa ◽

Multidrug Resistant ◽

Drug Resistant ◽

Vancomycin Resistant Enterococci ◽

Resistant Strains ◽

Vancomycin Resistant ◽

Drug Resistant Strains

The aim of this study was to evaluate the antibacterial activity of essential oil from Chamaecyparis obtusa against general infectious microbes and drug resistant strains of clinical origin. The results indicate that both essential oil and non-volatile residue have broad inhibitory activity against test strains. Essential oil and non-volatile residues showed antimicrobial activity not only against general infectious bacteria, but also against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) strains.

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The Biology and Role of Interleukin-32 in Tuberculosis

Journal of Immunology Research ◽

10.1155/2018/1535194 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Wu Li ◽

Wanyan Deng ◽

Jianping Xie

Keyword(s):

Multidrug Resistant ◽

Drug Resistant ◽

Host Molecule ◽

Tuberculosis Control ◽

Promising Alternative ◽

Extensively Drug Resistant ◽

Important Host ◽

Resistant Strains ◽

Drug Resistant Strains

Tuberculosis, caused by Mycobacterium tuberculosis, remains a leading cause of morbidity and mortality globally, with nearly 10.4 million new cases of incidence and over 1.7 million deaths annually. Drug-resistant M. tuberculosis strains, especially multidrug-resistant or extensively drug-resistant strains, have further intensified the problem associated with tuberculosis control. Host-directed therapy is a promising alternative for tuberculosis control. IL-32 is increasingly recognized as an important host molecule against tuberculosis. In this review, we highlight the proinflammatory properties of IL-32 and the mode of action of IL-32 in mycobacterial infections to inspire the development of novel immunity-based countermeasures and host-directed therapies against tuberculosis.

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CURRENTLY USED ANTI-TUBERCULAR AGENTS, THEIR ANALOGUES AND RECENTLY DEVELOPED DRUGS

INDIAN DRUGS ◽

10.53879/id.49.07.p0005 ◽

2012 ◽

Vol 49 (07) ◽

pp. 5-19

Author(s):

A Mohammad ◽

Keyword(s):

Antimicrobial Activity ◽

Side Effects ◽

Multidrug Resistant ◽

Drug Resistant ◽

Duration Of Treatment ◽

Duration Of Therapy ◽

Drug Molecules ◽

Prolonged Duration ◽

Resistant Strains ◽

Reduced Toxicity

Tuberculosis (TB) is one of most prevailing diseases, responsible for the morbidity and mortality of a large number of populations worldwide. Traditionally, it has relied on a limited number of drugs such as isoniazid, rifampicin, ethambutol, streptomycin, ethionamide and pyrazinamide. However, many of these drugs have different disadvantages such as prolonged duration of treatment, host toxicity and ineffectiveness against resistant strains. This has motivated the search of newer drug molecules, capable of rapid mycobactericidal action with shortened duration of therapy, reduced toxicity and enhanced activity against multidrug resistant strains. These observations have been guiding for the currently used and newly developed anti-tubercular agents that possess potent antimicrobial activity and their side effects, activity against multi drug resistant Mycobacterium, and also in patients co-infected with HIV/AIDS.

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Antituberculosis activities of clofazimine and its new analogs B4154 and B4157.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.40.3.633 ◽

1996 ◽

Vol 40 (3) ◽

pp. 633-636 ◽

Cited By ~ 46

Author(s):

V M Reddy ◽

G Nadadhur ◽

D Daneluzzi ◽

J F O'Sullivan ◽

P R Gangadharam

Keyword(s):

Multidrug Resistant ◽

New Drugs ◽

Drug Resistant ◽

Antituberculosis Drugs ◽

Resistant Tuberculosis ◽

Chemotherapeutic Activity ◽

Resistant Strains ◽

Intracellular Activities ◽

Moderate Resistance ◽

Drug Resistant Strains

In our efforts to develop new drugs for the treatment of tuberculosis, especially that caused by multidrug-resistant strains, we investigated clofazimine (CFM) and two of its analogs, B4154 and B4157, for their antituberculosis activities. Twenty M. tuberculosis strains were tested, including 16 drug-resistant strains (strains resistant to one or more antituberculosis drugs), for their susceptibilities to these three agents. All of the strains were found to be susceptible to B4154 and B4157, and one strain showed moderate resistance to CFM. The MICs of B4154, B4157, and CFM at which 90% of strains were inhibited were 0.25, 0.12, and < or = 1.0 microgram/ml, respectively. The intracellular activities of CFM and B4157 were superior to that of B4154. The chemotherapeutic activities of the three compounds were evaluated in C57BL/6 mice. At a dose of 20 mg/kg of body weight, the activity of CFM was slightly superior to that of B4157; however, both compounds prevented mortality and caused a significant reduction in the numbers of CFU in the lungs and spleens. The animals treated with B4157 showed less pigmentation than animals treated with CFM. The chemotherapeutic activity of CFM was comparable to those of rifampin and isoniazid. Complete susceptibility of multidrug-resistant strains to CFM and B4157 and the therapeutic efficacies of these compounds against mouse tuberculosis make these drugs attractive agents for the treatment of drug-resistant tuberculosis.

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Identification, Typing, Antifungal Resistance Profile, and Biofilm Formation ofCandida albicansIsolates from Lebanese Hospital Patients

BioMed Research International ◽

10.1155/2014/931372 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 13

Author(s):

Ibrahim Bitar ◽

Roy A. Khalaf ◽

Houda Harastani ◽

Sima Tokajian

Keyword(s):

Biofilm Formation ◽

Fungal Pathogens ◽

Recurrent Infection ◽

Multidrug Resistant ◽

Antifungal Resistance ◽

Drug Resistant ◽

Treatment Regimens ◽

Evolutionary Relatedness ◽

Resistant Strains ◽

Drug Resistant Strains

As leading opportunistic fungal pathogens identification and subtyping ofCandidaspecies are crucial in recognizing outbreaks of infection, recognizing particularly virulent strains, and detecting the emergence of drug resistant strains. In this study our objective was to compare identification ofCandida albicansby the hospitals through the use of conventional versus identification based on the ITS (Internal Transcribed Spacer) and to assess biofilm forming capabilities, drug resistance patterns and correlate these with MLST typing. ITS typing revealed a 21.2% hospital misidentification rate. Multidrug resistance to three drugs out of four tested was detected within 25% of the isolates raising concerns about the followed treatment regimens. Drug resistant strains as well as biofilm formers were phylogenetically related, with some isolates with significant biofilm forming capabilities being correlated to those that were multidrug resistant. Such isolates were grouped closely together in a neighbor-joining tree generated by MLST typing indicating phylogenetic relatedness, microevolution, or recurrent infection. In conclusion, this pilot study gives much needed insight concerningC. albicansisolates circulating in Lebanese hospitals and is the first study of its kind correlating biofilm formation, antifungal resistance, and evolutionary relatedness.

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Multidrug-Resistant Tuberculosis in Alberta and British Columbia, 1989 to 1998

Canadian Respiratory Journal ◽

10.1155/1999/456395 ◽

1999 ◽

Vol 6 (2) ◽

pp. 155-160 ◽

Cited By ~ 11

Author(s):

Ahmed Hersi ◽

Kevin Elwood ◽

Robert Cowie ◽

Dennis Kunimoto ◽

Richard Long

Keyword(s):

British Columbia ◽

Multidrug Resistant ◽

Drug Resistant ◽

Foreign Born ◽

Resistant Tuberculosis ◽

Multidrug Resistant Tuberculosis ◽

Mdr Tb ◽

Resistant Strains ◽

Drug Resistant Strains ◽

Culture Positive

OBJECTIVE: To describe the extent of the problem of multidrug-resistant tuberculosis (MDR-TB) in Alberta and British Columbia from 1989 to 1998.DESIGN: A retrospective, population-based descriptive study of all notified MDR-TB cases in the context of all notified TB cases, all notified culture-positive TB cases and all notified drug-resistant TB cases.SETTING: Provinces of Alberta and British Columbia, and their TB registries.PATIENTS: All people with TB reported to the TB registries of Alberta and British Columbia between January 1, 1989 and June 30, 1998.MAIN OUTCOME MEASURES: Drug susceptibility testing was performed in all cases of culture-positive TB. Demographic, clinical and laboratory data on all cases of MDR-TB were recorded.RESULTS: Of 4606 notified cases of TB, 3553 (77.1%) were culture positive. Of these, 365 (10.3%) were drug resistant; of the drug-resistant cases, 24 (6.6%) were MDR. Most MDR-TB patients were foreign-born; of the four Canadian-born patients, two were infected while travelling abroad. Although foreign-born patients were significantly more likely to harbour drug-resistant strains, 14.3% versus 4.8%, respectively (P<0.001), among those who were harbouring a drug-resistant strain, the proportion of Canadian-born versus foreign-born patients with an MDR strain was the same (6.7% versus 6.6%, respectively). From 1994 to 1998 versus 1989 to 1993, the proportion of all drug-resistant strains that were MDR was greater (9.0% versus 4.3%, respectively), but the difference was not statistically significant. Isolates from 16 of the 24 MDR-TB cases had been archived. Each of these was fingerprinted and found to be unique. Most MDR-TB cases (88%) were respiratory. Of those tested for human immunodeficiency virus (n=17), only one was seropositive. MDR-TB was ‘acquired’ in 67% and ‘primary’ in 33% of cases. Eight (33%) of the MDR-TB cases received curative courses of treatment, six (25%) are still being treated, and the remainder have either died (five, 21%), transferred out (four, 17%) or become ‘chronic’ (one, 4%). No secondary case of MDR-TB has been identified in Alberta and British Columbia.CONCLUSIONS: Most MDR-TB in Alberta and British Columbia is imported. The proportion of all drug-resistant cases that are MDR appears to be increasing, but not because of disease acquired from recent contact with MDR-TB in Canada.

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In Vitro Activity and MIC of Sitafloxacin against Multidrug-Resistant and Extensively Drug-Resistant Mycobacterium tuberculosis Isolated in Thailand

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00825-17 ◽

2017 ◽

Vol 62 (1) ◽

Cited By ~ 1

Author(s):

Manoon Leechawengwongs ◽

Therdsak Prammananan ◽

Sarinya Jaitrong ◽

Pamaree Billamas ◽

Nampueng Makhao ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Critical Concentration ◽

Multidrug Resistant ◽

Quinolone Resistance ◽

Drug Resistant ◽

Content Type ◽

Extensively Drug Resistant ◽

Resistant Strains ◽

Drug Resistant Strains

ABSTRACT New fluoroquinolones (FQs) have been shown to be more active against drug-resistant Mycobacterium tuberculosis strains than early FQs, such as ofloxacin. Sitafloxacin (STFX) is a new fluoroquinolone with in vitro activity against a broad range of bacteria, including M. tuberculosis. This study aimed to determine the in vitro activity of STFX against all groups of drug-resistant strains, including multidrug-resistant M. tuberculosis (MDR M. tuberculosis), MDR M. tuberculosis with quinolone resistance (pre-XDR), and extensively drug-resistant (XDR) strains. A total of 374 drug-resistant M. tuberculosis strains were tested for drug susceptibility by the conventional proportion method, and 95 strains were randomly submitted for MIC determination using the microplate alamarBlue assay (MABA). The results revealed that all the drug-resistant strains were susceptible to STFX at a critical concentration of 2 μg/ml. Determination of the MIC90s of the strains showed different MIC levels; MDR M. tuberculosis strains had a MIC90 of 0.0625 μg/ml, whereas pre-XDR and XDR M. tuberculosis strains had identical MIC90s of 0.5 μg/ml. Common mutations within the quinolone resistance-determining region (QRDR) of gyrA and/or gyrB did not confer resistance to STFX, except that double mutations of GyrA at Ala90Val and Asp94Ala were found in strains with a MIC of 1.0 μg/ml. The results indicated that STFX had potent in vitro activity against all the groups of drug-resistant M. tuberculosis strains and should be considered a new repurposed drug for treatment of multidrug-resistant and extensively drug-resistant TB.

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Sontochin as a Guide to the Development of Drugs against Chloroquine-Resistant Malaria

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00100-12 ◽

2012 ◽

Vol 56 (7) ◽

pp. 3475-3480 ◽

Cited By ~ 10

Author(s):

Sovitj Pou ◽

Rolf W. Winter ◽

Aaron Nilsen ◽

Jane Xu Kelly ◽

Yuexin Li ◽

...

Keyword(s):

Multidrug Resistant ◽

Plasmodium Yoelii ◽

Significant Activity ◽

Drug Resistant ◽

Content Type ◽

Resistant Strains ◽

Drug Resistant Strains ◽

Derivatives Of

ABSTRACTSontochin was the original chloroquine replacement drug, arising from research by Hans Andersag 2 years after chloroquine (known as “resochin” at the time) had been shelved due to the mistaken perception that it was too toxic for human use. We were surprised to find that sontochin, i.e., 3-methyl-chloroquine, retains significant activity against chloroquine-resistant strains ofPlasmodium falciparum in vitro. We prepared derivatives of sontochin, “pharmachins,” with alkyl or aryl substituents at the 3 position and with alterations to the 4-position side chain to enhance activity against drug-resistant strains. Modified with an aryl substituent in the 3 position of the 7-chloro-quinoline ring, Pharmachin 203 (PH-203) exhibits low-nanomolar 50% inhibitory concentrations (IC50s) against drug-sensitive and multidrug-resistant strains andin vivoefficacy against patent infections ofPlasmodium yoeliiin mice that is superior to chloroquine. Our findings suggest that novel 3-position aryl pharmachin derivatives have the potential for use in treating drug resistant malaria.

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Nickel chelation therapy as an approach to combat multi-drug resistant enteric pathogens

Scientific Reports ◽

10.1038/s41598-019-50027-0 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Stéphane L. Benoit ◽

Alan A. Schmalstig ◽

John Glushka ◽

Susan E. Maier ◽

Arthur S. Edison ◽

...

Keyword(s):

Oral Delivery ◽

Galleria Mellonella ◽

Multidrug Resistant ◽

Enteric Pathogens ◽

Control Group ◽

Drug Resistant ◽

Novel Approach ◽

Resistant Strains ◽

Pathogen Colonization ◽

Drug Resistant Strains

Abstract The nickel (Ni)-specific chelator dimethylglyoxime (DMG) has been used for many years to detect, quantitate or decrease Ni levels in various environments. Addition of DMG at millimolar levels has a bacteriostatic effect on some enteric pathogens, including multidrug resistant (MDR) strains of Salmonella Typhimurium and Klebsiella pneumoniae. DMG inhibited activity of two Ni-containing enzymes, Salmonella hydrogenase and Klebsiella urease. Oral delivery of nontoxic levels of DMG to mice previously inoculated with S. Typhimurium led to a 50% survival rate, while 100% of infected mice in the no-DMG control group succumbed to salmonellosis. Pathogen colonization numbers from livers and spleens of mice were 10- fold reduced by DMG treatment of the Salmonella-infected mice. Using Nuclear Magnetic Resonance, we were able to detect DMG in the livers of DMG-(orally) treated mice. Inoculation of Galleria mellonella (wax moth) larvae with DMG prior to injection of either MDR K. pneumoniae or MDR S. Typhimurium led to 40% and 60% survival, respectively, compared to 100% mortality of larvae infected with either pathogen, but without prior DMG administration. Our results suggest that DMG-mediated Ni-chelation could provide a novel approach to combat enteric pathogens, including recalcitrant multi-drug resistant strains.

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