scholarly journals Development of Antimicrobial Phototreatment Tolerance: Why the Methodology Matters

2021 ◽  
Vol 22 (4) ◽  
pp. 2224
Author(s):  
Aleksandra Rapacka-Zdonczyk ◽  
Agata Wozniak ◽  
Joanna Nakonieczna ◽  
Mariusz Grinholc

Due to rapidly growing antimicrobial resistance, there is an urgent need to develop alternative, non-antibiotic strategies. Recently, numerous light-based approaches, demonstrating killing efficacy regardless of microbial drug resistance, have gained wide attention and are considered some of the most promising antimicrobial modalities. These light-based therapies include five treatments for which high bactericidal activity was demonstrated using numerous in vitro and in vivo studies: antimicrobial blue light (aBL), antimicrobial photodynamic inactivation (aPDI), pulsed light (PL), cold atmospheric plasma (CAP), and ultraviolet (UV) light. Based on their multitarget activity leading to deleterious effects to numerous cell structures—i.e., cell envelopes, proteins, lipids, and genetic material—light-based treatments are considered to have a low risk for the development of tolerance and/or resistance. Nevertheless, the most recent studies indicate that repetitive sublethal phototreatment may provoke tolerance development, but there is no standard methodology for the proper evaluation of this phenomenon. The statement concerning the lack of development of resistance to these modalities seem to be justified; however, the most significant motivation for this review paper was to critically discuss existing dogma concerning the lack of tolerance development, indicating that its assessment is more complex and requires better terminology and methodology.

Author(s):  
Behiye Şenel ◽  
Gülay Büyükköroğlu

Nanocarriers with various compositions and biological properties are frequently used systems for in-vitro/in-vivo vaccination and gene transfer. In recent years, developments in nanotechnology have focused on the design and synthesis of nanocarriers that have new properties and can be modified for gene and vaccine delivery. In the favorable results obtained from in-vivo studies performed, they increase interest in these developments and pave the way for their therapeutic use. Nanocarriers have become increasingly important because they can stabilize vaccine antigens and serve as adjuvants, with the advantage of easily transporting genetic material to the target site. In nanocarriers, the molecules involved are adsorbed to the surface or encapsulated in particulates. At the same time, surface modification of nanoparticles allows these systems to carry cargo molecules easily to target site. Among the most studied nanocarriers, lipidic and polymeric systems dendrimers, inorganic nanoparticles, cyclodextrins, cell penetration peptides, and ISCOMs are attracting attention.


2021 ◽  
Author(s):  
Xue Wang ◽  
Lili Xuan ◽  
Ying Pan

Melanoma is one of the deadliest forms of cancer, for which therapeutic regimens are usually limited by the development of resistance. Here, we fabricated the Fe3O4 nanoparticle clusters (NPCs) that have drawn widespread attention and investigated their role in the treatment of melanoma by photothermal therapy (PTT). Transmission electron microscopy imaging shows that our synthesized NPCs are spherically shaped with an averaged diameter of 329.2 nm. They are highly absorptive at the near-infrared 808 nm wavelength and efficient at converting light into local heat. In vitro experiments using light-field microscopy and MTT assay showed that Fe3O4 NPCs, in conjunction with near-infrared irradiation, effectively ablated A375 melanoma cells by inducing overt apoptosis. Consistently, in vivo studies using BALB/c mice found that intratumoral administration of Fe3O4 NPCs and concomitant in situ exposure to near-infrared light significantly inhibited growth of implanted tumor xenografts. Finally, we revealed, by experimental approaches including semi-quantitative PCR, western blot and immunohistochemistry, the heat shock protein HSP70 to be upregulated in response to PTT, suggesting this chaperone protein could be a plausible underlying mechanism for the observed therapeutic outcome. Altogether, our results highlight the promise of Fe3O4 NPCs as a new PTT option to treat melanoma.


2001 ◽  
Vol 5 (8) ◽  
pp. 645-651
Author(s):  
M. Peeva ◽  
M. Shopova ◽  
U. Michelsen ◽  
D. Wöhrle ◽  
G. Petrov ◽  
...  
Keyword(s):  

2005 ◽  
Vol 25 (1_suppl) ◽  
pp. S198-S198
Author(s):  
Joseph R Meno ◽  
Thien-son K Nguyen ◽  
Elise M Jensen ◽  
G Alexander West ◽  
Leonid Groysman ◽  
...  

1994 ◽  
Vol 72 (06) ◽  
pp. 942-946 ◽  
Author(s):  
Raffaele Landolfi ◽  
Erica De Candia ◽  
Bianca Rocca ◽  
Giovanni Ciabattoni ◽  
Armando Antinori ◽  
...  

SummarySeveral “in vitro” and “in vivo” studies indicate that heparin administration may affect platelet function. In this study we investigated the effects of prophylactic heparin on thromboxane (Tx)A2 biosynthesis “in vivo”, as assessed by the urinary excretion of major enzymatic metabolites 11-dehydro-TxB2 and 2,3-dinor-TxB2. Twenty-four patients who were candidates for cholecystectomy because of uncomplicated lithiasis were randomly assigned to receive placebo, unfractionated heparin, low molecular weight heparin or unfractionaed heparin plus 100 mg aspirin. Measurements of daily excretion of Tx metabolites were performed before and during the treatment. In the groups assigned to placebo and to low molecular weight heparin there was no statistically significant modification of Tx metabolite excretion while patients receiving unfractionated heparin had a significant increase of both metabolites (11-dehydro-TxB2: 3844 ± 1388 vs 2092 ±777, p <0.05; 2,3-dinor-TxB2: 2737 ± 808 vs 1535 ± 771 pg/mg creatinine, p <0.05). In patients randomized to receive low-dose aspirin plus unfractionated heparin the excretion of the two metabolites was largely suppressed thus suggesting that platelets are the primary source of enhanced thromboxane biosynthesis associated with heparin administration. These data indicate that unfractionated heparin causes platelet activation “in vivo” and suggest that the use of low molecular weight heparin may avoid this complication.


2020 ◽  
Vol 72 (5) ◽  
Author(s):  
Mario Fadin ◽  
Maria C. Nicoletti ◽  
Marzia Pellizzato ◽  
Manuela Accardi ◽  
Maria G. Baietti ◽  
...  
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document