Owing to their unique, nanoscale related optical properties, nanostructures assembled from molecular photosensitizers (PSs) have interesting applications in phototheranostics. However, most ...nanostructured PS assemblies are super‐quenched, thus, preventing their use in photodynamic therapy (PDT). Although some of these materials undergo stimuli‐responsive disassembly, which leads to partial recovery of PDT activity, their therapeutic potentials are unsatisfactory owing to a limited ability to promote generation reactive oxygen species (ROS), especially via type I photoreactions (i.e., not by 1O2 generation). Herein we demonstrate that a new, nanostructured phthalocyanine assembly, NanoPcA, has the ability to promote highly efficient ROS generation via the type I mechanism. The results of antibacterial studies demonstrate that NanoPcA has potential PDT applications.
Photodynamic nanodots self‐assembled from phthalocyanine molecules (NanoPcA) display highly efficient reactive oxygen species generation via a type I mechanism. Antibacterial studies demonstrate that NanoPcA has potential photodynamic therapy applications.
The use of formic acid (FA) to produce molecular H2 is a promising means of efficient energy storage in a fuel‐cell‐based hydrogen economy. To date, there has been a lack of heterogeneous catalyst ...systems that are sufficiently active, selective, and stable for clean H2 production by FA decomposition at room temperature. For the first time, we report that flexible pyridinic‐N‐doped carbon hybrids as support materials can significantly boost the efficiency of palladium nanoparticle for H2 generation; this is due to prominent surface electronic modulation. Under mild conditions, the optimized engineered Pd/CN0.25 catalyst exhibited high performance in both FA dehydrogenation (achieving almost full conversion, and a turnover frequency of 5530 h−1 at 25 °C) and the reversible process of CO2 hydrogenation into FA. This system can lead to a full carbon‐neutral energy cycle.
Pyridinic‐N‐tuned catalysis: An electron‐rich pyridinic‐N dopant modulates the electronic interactions between the active sites of palladium nanoparticles and the carbon support. Formic acid dehydrogenation at room temperature is significantly boosted by the pyridinic‐N‐doped palladium catalyst, presenting an efficient and reliable route to clean H2 generation and sustainable energy storage.
The Omicron (B.1.1.529) variant of SARS-CoV-2 emerged in November 2021 and is rapidly spreading among the human population
. Although recent reports reveal that the Omicron variant robustly escapes ...vaccine-associated and therapeutic neutralization antibodies
, the pathogenicity of the virus remains unknown. Here we show that the replication of Omicron is substantially attenuated in human Calu3 and Caco2 cells. Further mechanistic investigations reveal that Omicron is inefficient in its use of transmembrane serine protease 2 (TMPRSS2) compared with wild-type SARS-CoV-2 (HKU-001a) and previous variants, which may explain its reduced replication in Calu3 and Caco2 cells. The replication of Omicron is markedly attenuated in both the upper and lower respiratory tracts of infected K18-hACE2 mice compared with that of the wild-type strain and Delta (B.1.617.2) variant, resulting in its substantially ameliorated lung pathology. Compared with wild-type SARS-CoV-2 and the Alpha (B.1.1.7), Beta (1.351) and Delta variants, infection by Omicron causes the lowest reduction in body weight and the lowest mortality rate. Overall, our study demonstrates that the replication and pathogenicity of the Omicron variant of SARS-CoV-2 in mice is attenuated compared with the wild-type strain and other variants.
The application of phthalocyanines in photothermal therapy has attracted increasing interest in recent years. In this review, the design considerations for enhancing the photothermal effect of ...phthalocyanines are highlighted.
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•Recent progresses made in the use of phthalocyanines as contrast agents for photothermal therapy are outlined.•The main design considerations for enhancing the photothermal effect of phthalocyanine-based contrast agents are discussed.•The perspectives and challenges for the application of phthalocyanines as contrast agents for PTT are discussed.
Phthalocyanine, as a type of organic photothermal agent, has advantages including a definite chemical structure, repeatable synthesis, strong absorption in the near-infrared region, tunable photophysical and photochemical properties, and inherent biodegradability. This review focuses on the recent progress made in the application of phthalocyanines as contrast agents for photothermal therapy (PTT). The present review not only discusses the molecular and/or supramolecular design considerations for enhancing the PTT effect of phthalocyanines, but also provides the perspectives and challenges of the use of phthalocyanines as contrast agents for PTT.
Only rarely have polyoxometalates been found to form core–shell nanoclusters. Here, we succeeded in isolating a series of rare giant and all‐inorganic core–shell cobalt polyoxoniobates (Co−PONbs) ...with diverse shapes, nuclearities and original topologies, including 50‐nuclearity {Co12Nb38O132}, 54‐nuclearity {Co20Nb34O128}, 62‐nuclearity {Co26Nb36O140} and 87‐nuclearity {Co33Nb54O188}. They are the largest Co−PONbs and also the polyoxometalates containing the greatest number of Co ions and the largest cobalt clusters known thus far. These molecular Co−PONbs have intriguing and atomically precise core–shell architectures comprising unique cobalt oxide cores and niobate oxide shells. In particular, the encapsulated cobalt oxide cores with different nuclearities have identical compositions, structures and mixed‐valence Co3+/Co2+ states as the different sized Co−O moieties of the bulk cubic‐spinel Co3O4, suggesting that they can serve as various molecular models of the cubic‐spinel Co3O4. The successful construction of the series of the Co−PONbs reveals a feasible and versatile synthetic method for making rare core–shell heterometallic PONbs. Further, these new‐type core–shell bimetal species are promising cluster molecular catalysts for visible‐light‐driven CO2 reduction.
A series of rare Co−Nb‐based core–shell polyoxometalates containing 50, 54, 62 and 87 metal polyhedra is prepared. The cobalt oxide cores correspond to increasingly large molecular analogues of infinite cubic‐spinel Co3O4. They are the largest cobalt polyoxoniobates and the polyoxometalates with the greatest number of Co ions and the highest‐nuclearity cobalt clusters known thus far. They are shown to be efficient photocatalysts for CO2 reduction.
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•Recent progresses made in the development of phthalocyanines for photodynamic therapy are outlined.•Representative water-soluble phthalocyanines are presented.•Main targeting ...strategies are discussed.•Future challenges are also presented.
Owing to their high extinction coefficients, long absorption wavelengths, and modification tunable photophysical and photochemical properties, phthalocyanines (Pcs) have been widely used as photosensitizers for photodynamic therapy (PDT). Advances made in the past five years on the development of Pcs as medicinal photosensitizers are reviewed and the main design considerations for medicinal applications of these substances are discussed.
Phthalocyanine (Pc) molecules exhibit high extinction coefficients in near-infrared region, rendering them well-suited for phototherapies, but most of their applications are limited to the field of ...photodynamic therapy (PDT). Herein, for the first time, we illustrate that Pc molecules can be endowed with excellent photothermal properties by means of structural regulation rather than formation of aggregates. Three representative Pc derivatives show efficient activities of photothermal therapy (PTT) against human hepatocellular carcinoma cells. Among them, copper phthalocyanine (PcC1) exhibits a high
PTT efficacy against mice bearing S180 tumors. The unique investigation in this article should light up a perspective of Pc's new applications for PTT, which enable to make up the inherent defects of PDT.
The clinical prospect of sonodynamic therapy (SDT) has not been fully realized due to the scarcity of efficient sonosensitizers. Herein, we designed phthalocyanine–artesunate conjugates (e.g. ...ZnPcT4A), which could generate up to ca. 10‐fold more reactive oxygen species (ROS) than the known sonosensitizer protoporphyrin IX. Meanwhile, an interesting and significant finding of aggregation‐enhanced sonodynamic activity (AESA) was observed for the first time. ZnPcT4A showed about 60‐fold higher sonodynamic ROS generation in the aggregated form than in the disaggregated form in aqueous solutions. That could be attributed to the boosted ultrasonic cavitation of nanostructures. The level of the AESA effect depended on the aggregation ability of sonosensitizer molecules and the particle size of their aggregates. Moreover, biological studies demonstrated that ZnPcT4A had high anticancer activities and biosafety. This study thus opens up a new avenue the development of efficient organic sonosensitizers.
An interesting aggregation‐enhanced sonodynamic activity (AESA) effect was first observed based on the studies of phthalocyanine–artesunate conjugates and common organic sonosensitizers, which arose from boosted ultrasonic cavitation caused by nanostructured aggregates. We believed that the AESA effect in this work could open up a new avenue for the development of efficient sonosensitizers.
Human APOBEC3G (hA3G) is a cytidine deaminase that restricts replication of certain viruses. We have previously reported that hA3G was a host restriction factor against hepatitis C virus (HCV) ...replication, and hA3G stabilizers showed a significant inhibitory activity against HCV. However, the molecular mechanism of hA3G against HCV remains unknown. We show in this study that hA3G's C-terminal directly binds HCV non-structural protein NS3 at its C-terminus, which is responsible for NS3's helicase and NTPase activity. Binding of hA3G to the C-terminus of NS3 reduced helicase activity, and therefore inhibited HCV replication. The anti-HCV mechanism of hA3G appeared to be independent of its deamination activity. Although early stage HCV infection resulted in an increase in host hA3G as an intracellular response against HCV replication, hA3G was gradually diminished after a long-term incubation, suggesting an unknown mechanism(s) that protects HCV NS3 from inactivation by hA3G. The process represents, at least partially, a cellular defensive mechanism against HCV and the action is mediated through a direct interaction between host hA3G and HCV NS3. We believe that understanding of the antiviral mechanism of hA3G against HCV might open an interesting avenue to explore hA3G stabilizers as a new class of anti-HCV agents.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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