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Phototherapy, such as photodynamic therapy (PDT) and photothermal therapy (PTT), possesses unique characteristics of non-invasiveness and minimal side effects in cancer treatment, compared with conventional therapies. However, the ubiquitous tumor hypoxia microenvironments could severely reduce the efficacy of oxygen-consuming phototherapies. Perfluorocarbon (PFC) nanomaterials have shown great practical value in carrying and transporting oxygen, which makes them promising agents to overcome tumor hypoxia and extend reactive oxygen species (ROS) lifetime to improve the efficacy of phototherapy. In this review, we summarize the latest advances in PFC-based PDT and PTT, and combined multimodal imaging technologies in various cancer types, aiming to facilitate their application-oriented clinical translation in the future. [ABSTRACT FROM AUTHOR]

A study is performed of the effect amphiphilic polymer Pluronic F127 has on the activity and photostability of photodithazine (PZ) in the photogeneration of singlet oxygen (1О2) in a model reaction of photo-oxidation of tryptophan in water upon excitation with light at λ = 400 and 660 nm at different light power densities. The highest photocatalytic activity and photostability of photodithazine in 1O2 generation are observed upon excitation with light at a wavelength of 400 nm, a medium radiation power density, and in the presence of Pluronic F127 in the reaction medium. The model reactions can be used to select the photosensitizers (PS) of the system (the presence of amphiphilic polymer and other systems added along with photosensitizers) and the modes of the low-energy photodynamic effects on substrates characteristic of each photosensitizer that are most favorable for therapy (i.e., that contribute to the initiation of regenerative and immune processes). [ABSTRACT FROM AUTHOR]

TLD1433, a Ru(II) polypyridyl complex, was recently introduced. It can be activated in the 520 to 540 nm range. Here we report on the use of TLD1433 for the treatment of bladder carcinomas in vitro and in an in vivo orthotopic model. The electrostatic properties of the normal urothelium vs a tumor compromised urothelium provide for a high selective uptake ratio. In vitro, a 1000 difference in the LD50 between dark and 22.5 J cm−2 irradiation at 530 nm was achieved for two bladder cell lines (T24 and AY‐27). In dogs and rats the plasma concentration for TLD1433 was below 100 ng kg−1 at 72 hours following intravenous injection at a dose of up to 3.5 mg kg−1 and below 10 ng kg−1 following intrabladder instillation for 1 hour at a concentration of 6 mg mL−1. Successful tumor necrosis close to 1.5 mm in depth was achieved. [ABSTRACT FROM AUTHOR]

Microorganisms can be programmed to perform chemical synthesis via metabolic engineering. However, despite an increasing interest in the use of de novo metabolic pathways and designer whole‐cells for small molecule synthesis, the inherent synthetic capabilities of native microorganisms remain underexplored. Herein, we report the use of unmodified E. coli BL21(DE3) cells for the reduction of keto‐acrylic compounds and apply this whole‐cell biotransformation to the synthesis of aminolevulinic acid from a lignin‐derived feedstock. The reduction reaction is rapid, chemo‐, and enantioselective, occurs under mild conditions (37 °C, aqueous media), and requires no toxic transition metals or external reductants. This study demonstrates the remarkable promiscuity of central metabolism in bacterial cells and how these processes can be leveraged for synthetic chemistry without the need for genetic manipulation. [ABSTRACT FROM AUTHOR]

Advances in chemotherapy always depend on the physician's correct selection of a medicinal formulation in which the main active ingredient or complex of substances has the greatest therapeutic effect. From this point of view, the pharmacokinetics of injectable medicinal formulations are optimal in terms of achieving the required dose in the systemic circulation, as the bioavailability of an agent given intravenously reaches 100%. However, major problems in creating medicinal formulations are posed by medicinal substances with low solubility and the high lability of aqueous solutions of such substances. This review discusses the properties of current solubilizers used in the production of known hydrophobic antitumor formulations for parenteral use and in the development of new medicinal formulations of experimental compounds with cytotoxic effects and undergoing preclinical and clinical studies. [ABSTRACT FROM AUTHOR]

The abilities of solubilizers Cremophor EL, Tween 80, Emuxol 3, and Pluronic F-68 to deliver the novel promising photosensitizer β,β,β′,β′-tetramethyltribenzotetraazachlorin (HTBTAC) into A549 human lung adenocarcinoma cells in vitro were compared. It was found that the number of HTBTAC monomers in the solubilizer solutions correlated with the amount of fluorescent monomer accumulated in the cells. The HTBTAC monomer showed significantly higher ability to generate singlet oxygen than HTBTAC aggregates. It was established that Cremophor EL provided the maximum amount of HTBTAC monomers in solution and the best stability during storage of the composition. Cremophor EL improved the accumulation of HTBTAC monomer in A549 cell cytoplasm (reaching saturation after incubation for 2 h) and gave the maximum HTBTAC accumulation coefficient (0.7 ± 0.1). Experiments in vivo showed therapeutically significant antineoplastic activity for photodynamic therapy with HTBTAC stabilized in Cremophor EL solution (10%). [ABSTRACT FROM AUTHOR]

Microorganisms can be programmed to perform chemical synthesis via metabolic engineering. However, despite an increasing interest in the use of de novo metabolic pathways and designer whole-cells for small molecule synthesis, the inherent synthetic capabilities of native microorganisms remain underexplored. Herein, we report the use of unmodified E. coli BL21(DE3) cells for the reduction of keto-acrylic compounds and apply this whole-cell biotransformation to the synthesis of aminolevulinic acid from a lignin-derived feedstock. The reduction reaction is rapid, chemo-, and enantioselective, occurs under mild conditions (37 °C, aqueous media), and requires no toxic transition metals or external reductants. This study demonstrates the remarkable promiscuity of central metabolism in bacterial cells and how these processes can be leveraged for synthetic chemistry without the need for genetic manipulation., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Results of an in vivo biokinetic investigation of the photodynamic activity of a series of new photosensitizers including a tetraazachlorin derivative (2,3,3α,21α-tetrahydro-2-methyl-3α,8,13,18-tetraphenyl-5,10,15,20-tetraaza-1 H,22 H,24 H-pyrrolo[3, 4- b]porphine), two difluoroboryl-substituted complexes of 3,3′-diphenylazadiisoindolylmethene { N, N-difluoroboryl- N-[3-(4- t-butylphenyl)-2 H-isoindol-1-yl)]- N-[3-(4- t-butylphenyl)-1 H-isoindol-1-yliden]amine and N, N-difluoroboryl-1-[3-(4-methoxyphenyl)-2 H-isoindol-1-yl)]- N-[3-(4-methoxyphenyl)-1 H-isoindol-1-yliden]amine}, and a sulfanyl-substituted phthalocyanine [1,8,15,22-tetrakis( t-butylsulfanyl)-29 H, 31 H-phthalocyanine] are reported. These compounds exhibit pronounced photodynamic activity in mice bearing solid Ehrlich ascites carcinoma and sarcoma S-37 upon intravenous injection as micellar suspensions in aqueous solutions (4%) of Cremophor EL and Proxanol 268. Acomparison of the tumor growth rate and the time of attaining a critical tumor volume in the test and control groups shows evidence for high photodynamic activity of the new photosensitizers. [ABSTRACT FROM AUTHOR]