scholarly journals Dually Acting Nonclassical 1,4-Dihydropyridines Promote the Anti-Tuberculosis (Tb) Activities of Clofazimine

Molecules ◽  
2019 ◽  
Vol 24 (16) ◽  
pp. 2873 ◽  
Author(s):  
Fabian Lentz ◽  
Norbert Reiling ◽  
Gabriella Spengler ◽  
Annamária Kincses ◽  
Andrea Csonka ◽  
...  
Keyword(s):  
Efflux Pump ◽  
Substituent Effects ◽  
Drug Efficacy ◽  
Second Line ◽  
First Line ◽  
Resistance Development ◽  
Cell Line Model ◽  
Pump Activity ◽  
T Lymphoma ◽  
Poor Efficacy

The number of effective antituberculotic drugs is strongly limited to four first-line drugs in standard therapy. In case of resistances second-line antibiotics are used with a poor efficacy and tolerability. Therefore, novel antituberculotic drugs are urgently needed. We synthesized novel nonclassical 1,4-dihydropyridines and evaluated their antituberculotic properties depending on substituent effects. Preferred substituents could be identified. As related classical 1,4-dihydropyridines are known as inhibitors of the transmembrane efflux pump ABCB1 in cancer cells, we wondered whether a use of our compounds may be of favour to enhance the antituberculotic drug efficacy of the second-line antituberculotic drug clofazimine, which is a known substrate of ABCB1 by a suggested inhibition of a corresponding efflux pump in Mycobacterium tuberculosis (Mtb). For this, we determined the ABCB1 inhibiting properties of our compounds in a mouse T-lymphoma cell line model and then evaluated the drug-enhancing properties of selected compounds in a co-application with clofazimine in our Mtb strain. We identified novel enhancers of clofazimine toxicity which could prevent clofazimine resistance development mediated by an efflux pump activity.

Social Representations and Commitment

2018 ◽  
Vol 23 (3) ◽  
pp. 233-249 ◽  
Author(s):  
Eric Bonetto ◽  
Fabien Girandola ◽  
Grégory Lo Monaco
Keyword(s):  
Social Representations ◽  
Social Representation ◽  
Second Line ◽  
Review Of The Literature ◽  
First Line ◽  
Research Perspectives ◽  
The Social ◽  
Bibliographic Search ◽  
English Articles

Abstract. This contribution consists of a critical review of the literature about the articulation of two traditionally separated theoretical fields: social representations and commitment. Besides consulting various works and communications, a bibliographic search was carried out (between February and December, 2016) on various databases using the keywords “commitment” and “social representation,” in the singular and in the plural, in French and in English. Articles published in English or in French, that explicitly made reference to both terms, were included. The relations between commitment and social representations are approached according to two approaches or complementary lines. The first line follows the role of commitment in the representational dynamics: how can commitment transform the representations? This articulation gathers most of the work on the topic. The second line envisages the social representations as determinants of commitment procedures: how can these representations influence the effects of commitment procedures? This literature review will identify unexploited tracks, as well as research perspectives for both areas of research.

mCRPC: Cabazitaxel zukünftige Second-line-Option nach Docetaxel?

2010 ◽  
Vol 01 (06) ◽  
pp. 282-282
Author(s):  
Birgit-Kristin Pohlmann
Keyword(s):  
Second Line ◽  
First Line

Bislang steht für Patienten mit metastasiertem kastrationsresistentem Prostatakarzinom (mCRPC), die auf die Standard-First-line-Chemotherapie mit Docetaxel nicht mehr adäquat ansprechen, keine Evidenz-basierte Therapieoption zur Verfügung. Große Hoffnungen verbinden sich daher mit Cabazitaxel, einer neuen Substanz, die diesen Patienten noch einmal die Chance auf eine Überlebenszeitverlängerung bietet. In den USA ist Cabazitaxel bereits für die Second-line-Behandlung beim mCRPC nach Docetaxel-Versagen zugelassen. In Europa ist die Zulassung für diese Indikation bean-tragt.

A Rational Sequencing of Anti-Angiogenic Agents as Second-Line Treatment Choice for mCRC Patients Progressing After a Bevacizumab-Based First Line

2020 ◽  
pp. 14-19
Author(s):  
Sara De Dosso
Keyword(s):  
Acquired Resistance ◽  
Predictive Biomarker ◽  
Cancer Therapies ◽  
Vascular Endothelial ◽  
Line Treatment ◽  
Second Line ◽  
First Line ◽  
Vegf Pathway ◽  
Effective Choice ◽  
Endothelial Growth Factor

A large proportion of patients with metastatic colorectal cancer (mCRC) experience disease progression after first-line treatment with chemotherapy and bevacizumab, an anti-angiogenic agent, as a result of acquired resistance. However, blocking angiogenesis by targeted therapy towards the vascular endothelial growth factor (VEGF) pathway still forms an essential part of the second-line treatment strategy. Although three approved evidence-based choices for angiogenic agents (continuing treatment with bevacizumab, ramucirumab and aflibercept) are currently available in the second line, making the most effective choice is challenging due to the lack of studies directly comparing these agents. Moreover, despite huge investigational efforts, no predictive biomarker for anti-angiogenic cancer therapies could be identified so far.

Efficacy and Toxicity of Addition of Bevacizumab to Chemotherapy in Patients with Metastatic Colorectal Cancer

2019 ◽  
Vol 21 (10) ◽  
pp. 718-724 ◽  
Author(s):  
Wen-Cong Ruan ◽  
Yue-Ping Che ◽  
Li Ding ◽  
Hai-Feng Li
Keyword(s):  
Colorectal Cancer ◽  
Adverse Event ◽  
Metastatic Colorectal Cancer ◽  
Line Treatment ◽  
Second Line ◽  
First Line ◽  
Second Line Therapy ◽  
Clinical Prognosis ◽  
Line Therapy ◽  
Significant Difference

Background: Pre-treated patients with first-line treatment can be offered a second treatment with the aim of improving their poor clinical prognosis. The therapy of metastatic colorectal cancer (CRC) patients who did not respond to first-line therapy has limited treatment options. Recently, many studies have paid much attention to the efficacy of bevacizumab as an adjuvant treatment for metastatic colorectal cancer. Objectives: We aimed to evaluate the efficacy and toxicity of bevacizumab plus chemotherapy compared with bevacizumab-naive based chemotherapy as second-line treatment in people with metastatic CRC. Methods: Electronic databases were searched for eligible studies updated to March 2018. Randomized-controlled trials comparing addition of bevacizumab to chemotherapy without bevacizumab in MCRC patients were included, of which, the main interesting results were the efficacy and safety profiles of the addition of bevacizumab in patients with MCRC as second-line therapy. Result: Five trials were eligible in the meta-analysis. Patients who received the combined bevacizumab and chemotherapy treatment in MCRC as second-line therapy showed a longer overall survival (OS) (OR=0.80,95%CI=0.72-0.89, P<0.0001) and progression-free survival (PFS) (OR=0.69,95%CI=0.61-0.77, P<0.00001). In addition, there was no significant difference in objective response rate (ORR) (RR=1.36,95%CI=0.82-2.24, P=0.23) or severe adverse event (SAE) (RR=1.02,95%CI=0.88-1.19, P=0.78) between bevacizumab-based chemotherapy and bevacizumabnaive based chemotherapy. Conclusion: Our results suggest that the addition of bevacizumab to the chemotherapy therapy could be an efficient and safe treatment option for patients with metastatic colorectal cancer as second-line therapy and without increasing the risk of an adverse event.

scholarly journals New Trimethoprim-Like Molecules: Bacteriological Evaluation and Insights into Their Action

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 709
Author(s):  
Marta Jorba ◽  
Marina Pedrola ◽  
Ouldouz Ghashghaei ◽  
Rocío Herráez ◽  
Lluis Campos-Vicens ◽  
...  
Keyword(s):  
Inhibitory Concentration ◽  
Efflux Pump ◽  
Synergistic Effects ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Detailed Characterization ◽  
Low Concentrations ◽  
Pump Activity ◽  
Bacteriological Evaluation ◽  
Kinetics Of

This work reports a detailed characterization of the antimicrobial profile of two trimethoprim-like molecules (compounds 1a and 1b) identified in previous studies. Both molecules displayed remarkable antimicrobial activity, particularly when combined with sulfamethoxazole. In disk diffusion assays on Petri dishes, compounds 1a and 1b showed synergistic effects with colistin. Specifically, in combinations with low concentrations of colistin, very large increases in the activities of compounds 1a and 1b were determined, as demonstrated by alterations in the kinetics of bacterial growth despite only slight changes in the fractional inhibitory concentration index. The effect of colistin may be to increase the rate of antibiotic entry while reducing efflux pump activity. Compounds 1a and 1b were susceptible to extrusion by efflux pumps, whereas the inhibitor phenylalanine arginyl β-naphthylamide (PAβN) exerted effects similar to those of colistin. The interactions between the target enzyme (dihydrofolate reductase), the coenzyme nicotinamide adenine dinucleotide phosphate (NADPH), and the studied molecules were explored using enzymology tools and computational chemistry. A model based on docking results is reported.

scholarly journals Immediate hypersensitivity reaction followed by successful oral desensitization to ursodiol

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Erika Yue Lee ◽  
Christine Song
Keyword(s):  
Hypersensitivity Reaction ◽  
Primary Biliary Cholangitis ◽  
Line Treatment ◽  
Second Line ◽  
Immediate Hypersensitivity ◽  
First Line ◽  
Case Presentation ◽  
Desensitization Protocol ◽  
First Line Treatment ◽  
Oral Desensitization

Abstract Background Immediate hypersensitivity reaction to ursodiol is rare and there is no previously published protocol on ursodiol desensitization. Case presentation A 59-year-old woman with primary biliary cholangitis (PBC) developed an immediate hypersensitivity reaction to ursodiol—the first-line treatment for PBC. When she switched to a second-line treatment, her PBC continued to progress. As such, she completed a novel 12-step desensitization protocol to oral ursodiol. She experienced recurrent pruritus after each dose following desensitization, which subsided after a month of being on daily ursodiol. Conclusion Immediate hypersensitivity reaction to ursodiol is uncommon. Our case demonstrated that this novel desensitization protocol to ursodiol could be safely implemented when alternative options are not available or have proven inferior in efficacy.

scholarly journals The TonB system in Aeromonas hydrophila NJ-35 is essential for MacA2B2 efflux pump-mediated macrolide resistance

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Yuhao Dong ◽  
Qing Li ◽  
Jinzhu Geng ◽  
Qing Cao ◽  
Dan Zhao ◽  
...  
Keyword(s):  
Aeromonas Hydrophila ◽  
Efflux Pump ◽  
Fold Increase ◽  
Activity Level ◽  
Macrolide Resistance ◽  
Wild Type ◽  
Iron Deprivation ◽  
Pump Activity ◽  
Tonb System ◽  
Increased Sensitivity

AbstractThe TonB system is generally considered as an energy transporting device for the absorption of nutrients. Our recent study showed that deletion of this system caused a significantly increased sensitivity of Aeromonas hydrophila to the macrolides erythromycin and roxithromycin, but had no effect on other classes of antibiotics. In this study, we found the sensitivity of ΔtonB123 to all macrolides tested revealed a 8- to 16-fold increase compared with the wild-type (WT) strain, but this increase was not related with iron deprivation caused by tonB123 deletion. Further study demonstrated that the deletion of tonB123 did not damage the integrity of the bacterial membrane but did hinder the function of macrolide efflux. Compared with the WT strain, deletion of macA2B2, one of two ATP-binding cassette (ABC) types of the macrolide efflux pump, enhanced the sensitivity to the same levels as those of ΔtonB123. Interestingly, the deletion of macA2B2 in the ΔtonB123 mutant did not cause further increase in sensitivity to macrolide resistance, indicating that the macrolide resistance afforded by the MacA2B2 pump was completely abrogated by tonB123 deletion. In addition, macA2B2 expression was not altered in the ΔtonB123 mutant, indicating that any influence of TonB on MacA2B2-mediated macrolide resistance was at the pump activity level. In conclusion, inactivation of the TonB system significantly compromises the resistance of A. hydrophila to macrolides, and the mechanism of action is related to the function of MacA2B2-mediated macrolide efflux.

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