Presence Of Photosensitizer Research Articles

Light‐Assisted Polyproton Dissociated PAAm‐PA Hydrogel‐Based Moisture‐Driven Electricity Generator with a Broad Operating Range

AbstractDue to its widespread availability and spontaneity, moisture electricity generation (MEG) holds unique advantages in self‐powered systems. However, it faces challenges, including the limitations of relying on a single kind of power generation and insufficient output performance. Inspired by the mechanisms of water absorption of plants, this paper explores a light‐moisture coordinated electricity generating hydrogel (L‐MEGH) device with flexible, scalable, and highly efficient energy conversion performance, which is obtained through the UV polymerization of hydrophilic acrylamide (AAM) and phytic acid (PA) in the presence of photosensitizers. The obtained hydrogel demonstrates superior moisture absorption and remarkable electricity generation stability across a range of humidity conditions. Notably, the open‐circuit voltage (Voc) of the L‐MEGH increased from 0.675 to 0.838 V after the addition of photosensitizers (Erythrosin B, E) (the significant enhancement, up to 24%), and the short‐circuit current (Isc) reaching 635.543 µA. This L‐MEGH can realize stable electrical output even under extreme temperatures, producing 0.5 V at −20 °C for 45 h. The scalable L‐MEGHs (connected on‐demand in series/parallel) can power various commercial electronics, including nighttime illumination, mobile phones, and health monitoring sensors. This work pioneers a sustainable power generation pathway capable of enhancing performance through the hybrid collection of multiple natural energy sources.

Clinical insights into juvenile myoclonic epilepsy: Our experience

Aim: Juvenile Myoclonic Epilepsy (JME) is predominantly observed during adolescence, characterized by myoclonic jerks exacerbated by sleep deprivation. Generalized tonic-clonic (GTC) and absence seizures are also common in JME. Patients are often photosensitive and usually require long-term treatment. This study aims to retrospectively evaluate the clinical, demographic, and electroencephalography (EEG) findings of patients diagnosed with JME at our Pediatric Neurology Clinic. Methods: Patients who were followed up at the Department of Pediatric Neurology between 2017-2022, diagnosed with JME based on clinical and EEG findings, and had at least one year of follow-up were included in this study. The clinical characteristics of the patients, as well as their diagnostic and follow-up EEG results, were retrospectively reviewed. Results: Of the patients, 12 (55%) were female and 10 (45%) were male. The mean age of the patients was 17±1 (range 14-18) years, and the average age at first seizure was 13±2 (range 12-16) years. When examining the types of seizures in our cases; 12 (55%) had myoclonic and GTC seizures, 4 (18%) had a combination of myoclonic-GTC-absence, and 6 (27%) had isolated myoclonic seizures. EEG results showed that 6 (27%) of the patients had spike and multiple spike waves at 3-5.5 Hz during sleep, while the remaining 16 (73%) had these during wakefulness. Fourteen (64%) of the patients responded to photic stimulation. Six (27%) of the patients had a first-degree relative with a history of epilepsy. A significant association was found between the presence of photosensitivity and family history of epilepsy (p=0.03). Conclusion: Juvenile myoclonic epilepsy is a type of epilepsy observed in the adolescent period, characterized by myoclonic jerks and photosensitivity. In patients with JME who have a family history of epilepsy, photosensitivity is more commonly observed

Development of a Convenient and Quantitative Method for Evaluating Photosensitizing Activity Using Thiazolyl Blue Formazan Dye.

Photosensitizers cause oxidative damages in various biological systems under light. In this study, the method for analyzing photosensitizing activity of various dietary and medicinal sources was developed using 1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan (thiazolyl blue formazan; MTT-F) as a probe. Significant and quantitative decolorization of MTT-F was observed in the presence of photosensitizers used in this study under light but not under dark conditions. The decolorization of MTT-F occurred irradiation time-, light intensity-, and photosensitizer concentration-dependently. The decolorized MTT-F was reversibly reduced by living cells; the LC-MS/MS results indicated the formation of oxidized products with -1 m/z of base peak from MTT-F, suggesting that MTT-F decolorized by photosensitizers was its corresponding tetrazolium. The present results indicate that MTT-F is a reliable probe for the quantitative analysis of photosensitizing activities, and the MTT-F-based method can be an useful tool for screening and evaluating photosensitizing properties of various compounds used in many industrial purposes.

A PROTAC Augmenter for Photo-Driven Pyroptosis in Breast Cancer.

Proteolysis targeting chimera (PROTAC) has recently emerged as a promising strategy for inducing post-translational knockdown of target proteins in disease treatment. The degradation of bromodomain-containing protein 4 (BRD4), an essential nuclear protein for gene transcription, induced by PROTAC is proposed as an epigenetic approach to treat breast cancer. However, the poor membrane permeability and indiscriminate distribution of PROTAC in vivo results in low bioavailability, limiting its development and application. Herein, a nano "targeting chimera" (abbreviated as L@NBMZ) consisting of BRD4-PROTAC combined with a photosensitizer, to serve as the first augmenter for photo-driven pyroptosis in breast cancer, is developed. With excellent BRD4 degradation ability, high biosafety, and biocompatibility, L@NBMZ blocks gene transcription by degrading BRD4 through proteasomes in vivo, and surprisingly, induces the cleavage of caspase-3. This type of caspase-3 cleavage is synergistically amplified by light irradiation in the presence of photosensitizers, leading to efficient photo-driven pyroptosis. Both in vitro and in vivo outcomes demonstrate the remarkable anti-cancer efficacy of this augmenter, which significantly inhibits the lung metastasis of breast cancer in vivo. Thus, the photo-PROTAC "targeting chimera" augmenter construction strategy may pave a new way for expanding PROTAC applications within anti-cancer paradigms.

FAP Targeting of Photosensitizer-Loaded Polymersomes for Increased Light-Activated Cell Killing.

As current chemo- and photodynamic cancer therapies are associated with severe side effects due to a lack of specificity and to systemic toxicity, innovative solutions in terms of targeting and controlled functionality are in high demand. Here, we present the development of a polymersome nanocarrier equipped with targeting molecules and loaded with photosensitizers for efficient uptake and light-activated cell killing. Polymersomes were self-assembled in the presence of photosensitizers from a mixture of nonfunctionalized and functionalized PDMS-b-PMOXA diblock copolymers, the latter designed for coupling with targeting ligands. By encapsulation inside the polymersomes, the photosensitizer Rose Bengal was protected, and its uptake into cells was mediated by the nanocarrier. Inhibitor of fibroblast activation protein α (FAPi), a ligand for FAP, was attached to the polymersomes' surface and improved their uptake in MCF-7 breast cancer cells expressing relatively high levels of FAP on their surface. Once internalized by MCF-7, irradiation of Rose Bengal-loaded FAPi-polymersomes generated reactive oxygen species at levels high enough to induce cell death. By combining photosensitizer encapsulation and specific targeting, polymersomes represent ideal candidates as therapeutic nanocarriers in cancer treatment.

Hybrid ceramic repair strength, surface roughness, and bond failure, using methylene blue-activated low-level laser therapy, Carbon dioxide, and Ti: Al2O3 laser

AimsTo evaluate the impact of various pretreatment regimes (LLLT, Ti-sapphire laser, CO2, and HFA-S) on hybrid ceramics, specifically focusing on their ability to enhance repair strength and minimize surface roughness (Ra). Material and methodsDiscs were made from hybrid ceramics and after disinfection were randomly divided into four groups based on different surface conditioning techniques. Each group consisted of 15 discs, resulting in a total sample size of 60. dics in group 1 was surface treated with Low-level laser therapy (LLLT) using methylene blue (MB), Discs in group 2 with Ti-sapphire laser, Discs in group 3 with CO2 laser, and discs in group 4 with HFA-S. Five samples from each group were assessed for Ra. The remaining 10 samples from each group underwent repair using a porcelain repair kit in adherence to the planned instructions. The bond strength of each sample in all groups was measured using a universal testing machine. Following the bond strength testing, the specimens from all study groups were analyzed to determine the mode of failure. To evaluate the data, a two-way analysis of variance (ANOVA) was used, followed by post hoc multiple comparisons. ResultsThe highest repair bond strength was observed in group 4 hybrid ceramics pretreated with HFA-S (19.05±0.79 MPa). The lowest repair bond scores were observed in group 1 hybrid ceramics preconditioned with LLLT in the presence of Photosensitizer (13.41±0.36 MPa). The highest Ra scores were exhibited in group 2 surface treated with Ti-sapphire laser (0.0515±0.16 µm) and the lowest Ra scores were observed in Group 4 HFA-S (0.0311±0.79 µm). Predominant bond failure among different investigated groups was cohesive. ConclusionThe current gold standard for hybrid ceramic conditioning is the use of hydrofluoric acid (HFA) combined with a silane coupling agent. Low-level laser therapy with methylene blue photosensitizer is not recommended for the treatment of hybrid ceramics.

An Efficient Intercalation Supramolecular Structure for Photocatalytic CO2 Reduction to Ethylene Under Visible Light

AbstractPhotocatalytic CO2 reduction (CO2PR) into multi‐carbon products (especially C2H4) is a highly attractive route for global carbon cycle, however, which is seriously limited by sluggish C‐C coupling kinetics and competitive hydrogen evolution reaction (HER) and so on. Herein, the fabrication of a novel supramolecular assembly of NiAl‐Fe‐TCPP is reported by intercalating iron porphyrin (Fe‐TCPP) into NiAl‐layered double hydroxide (NiAl‐LDH), and the resultant NiAl‐Fe‐TCPP exhibit superior catalytic performance on CO2PR to C2H4 under visible light irradiation in presence of photosensitizer. A high C2H4 selectivity up to 93.4% in the carbon‐containing products with the production rate as high as 24.7 µmol h−1 can be achieved over NiAl‐Fe‐TCPP. The ex/in situ X–ray absorption spectoscopy (XAS) indicates that the electron transfer between NiAl‐LDH and Fe‐TCPP can promote the generation of low‐valence of Fe sites, resulting in the efficient production of C2H4. The spin‐polarized density functional theory (DFT) calculations find that the synergistic mechanism that CO2 molecules are activated to CO on NiAl‐LDH and then spilled to Fe‐TCPP and coupled to COCHO#, which is further reduced to C2H4, are feasible in the perspective of Gibbs free energy. Moreover, the strong host‐guest interactions between NiAl‐LDH and Fe‐TCPP lead to the promoted photocatalytic activity and superior cycle stability.

Evaluation of relative efficiency of PDT photosensitizers in producing hydroxyl radicals and singlet oxygen in aqueous media using a UV-visible spectroscopy pNDA dosage.

In order to improve the performance of PDT, it is important to develop new photosensitizers that induce the formation of both hydroxyl radicals and singlet oxygen. In this work, we developed and validated the experimental conditions and reproducibility for the evaluation of relative efficiency of hydroxyl radicals and singlet oxygen production by studying the bleaching of p-nitrosoaniline (pNDA) using a continuous flow UV-visible spectroscopy method in presence of photosensitizers in PBS media. Rapid data sampling made possible to analyze the kinetics of the bleaching by using a mathematical modeling. The pNDA dosage is specific of hydroxyl radicals' production without l-histidine and of singlet oxygen production in presence of l-histidine. A statistical approach is used to precisely evaluate the reliability of the results and to be able to compare different photosensitizers between them such as Methylene Blue and Brillant Blue G.

Photo-Oxidative Stability of Aqueous Model Systems Enriched with Omega-3 Long-Chain Polyunsaturated Fatty Acid-Rich Microalgae as Compared to Autoxidative Stability.

Several species of microalgae are promising as an alternative source of omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). Photoautotrophic species show the greatest potential, since incorporating them into food products leads to oxidatively stable products; however, the presence of photosensitizers could reduce the shelf-life due to the appearance of photo-oxidation on exposure to light. This study investigated the oxidative impact of illumination for aqueous model suspensions enriched with Phaeodactylum (phototrophic microalgae─containing potential photosensitizers) and Schizochytrium (heterotrophic microalgae─lacking photosensitizers) during storage for 28 days at 37 °C. Primary (peroxide value) and secondary (volatiles with gas chromatography (GC)-mass spectrometry) oxidation products, n-3 LC-PUFA content (GC), and pigments (high-pressure liquid chromatography) were assessed. The results showed that photo-oxidation did not cause oxidative instability for Phaeodactylum samples compared with strong autoxidation in Schizochytrium samples. For the Phaeodactylum-enriched suspensions, only minimal photo-oxidation could be detected and the n-3 LC-PUFA content remained stable throughout storage regardless of illumination.

Sensitizer-enhanced two-photon patterning of biomolecules in photoinstructive hydrogels

Photoresponsive hydrogels can be employed to coordinate the organization of proteins in three dimensions (3D) and thus to spatiotemporally control their physiochemical properties by light. However, reversible and user-defined tethering of proteins and protein complexes to biomaterials pose a considerable challenge as this is a cumbersome process, which, in many cases, does not support the precise localization of biomolecules in the z direction. Here, we report on the 3D patterning of proteins with polyhistidine tags based on in-situ two-photon lithography. By exploiting a two-photon activatable multivalent chelator head, we established the protein mounting of hydrogels with micrometer precision. In the presence of photosensitizers, a substantially enhanced two-photon activation of the developed tool inside hydrogels was detected, enabling the user-defined 3D protein immobilization in hydrogels with high specificity, micrometer-scale precision, and under mild light doses. Our protein-binding strategy allows the patterning of a wide variety of proteins and offers the possibility to dynamically modify the biofunctional properties of materials at defined subvolumes in 3D.

Clinical subgroup clustering analysis in a systemic lupus erythematosus cohort from Western Pennsylvania.

Systemic lupus erythematosus (SLE) is a complex heterogenous autoimmune disease that can affect multiple organs. We performed clinical clustering analysis to describe a lupus cohort from the University of Pittsburgh Medical Center. A total of 724 patients who met the American College of Rheumatology (ACR) classification criteria for SLE were included in this study. Clustering was performed using the ACR classification criteria and the partitioning around medoid method. Correlation analysis was performed using the Spearman's Rho test. Patients with SLE in our cohort identify three district clinical disease subsets. Patients in cluster 1 were significantly more likely to develop renal and hematologic involvement, and had overrepresentation in African-American and male lupus patients. Clusters 2 and 3 identified a milder disease, with a significantly less likelihood of organ complications. Patients in cluster 2 are characterized by malar rash and photosensitivity, while patients in cluster 3 are characterized by oral ulcers, which is present in ~90% of patients within this cluster. The presence of photosensitivity or oral ulcers appears to be protective against the development of lupus nephritis in our cohort. We describe a large cohort of SLE from Western Pennsylvania and identify three distinct clinical disease subgroups. Clustering analysis might help to better manage and predict disease complications in heterogenous diseases like lupus.

Investigation of transient eye closure evoked with bright light in the patients with intermittent exotropia

BackgroundThis study aimed to present a simple method for evaluating transient eye closure (TEC) evoked by bright light and find the agreement between TEC and photosensitivity. We also assessed the associated factors with TEC in the patients with intermittent exotropia (IXT).MethodsIn this retrospective study, IXT patients were exposed to different brightness: darkness, low-intensity white light, and high-intensity white light using a near-infrared camera vision monitor system (Mon CV3, Metrovision, France). TEC was considered to be present if the subject closed his or her eyes immediately, and for more than half of the scotopic lid fissure distance in response to the high-intensity or low-intensity photopic stimulus of light, compared with lid fissure distance in the scotopic phase. We assessed the presence of photosensitivity using a questionnaire and evaluated the agreement between TEC and photosensitivity. We also investigated the sensory fusion, motor fusion, and pupil dynamic components for the existence of TEC in IXT patients.ResultsSixty-one patients with IXT were included. With the new method to evaluate TEC under different light intensities, 27 (44.3%) of the 61 IXT patients showed TEC, and 34 (55.7%) did not demonstrate TEC. TEC under high-intensity white light had a strong correlation with self-reporting photosensitivity (r = 0.77). The smaller angle of deviation at near was associated with the presence of TEC, with statistical significance (p = 0.04). Normal sensory status at a distance was significantly associated with TEC (p < 0.01). Multivariate analysis using multiple logistic regression analysis showed that normal sensory status was significantly associated with TEC (p = 0.02).ConclusionsThe test using a near-infrared camera vision monitor system was a simple and objective tool in identifying TEC evoked by bright light. The presence of TEC strongly correlated with self-reporting photosensitivity in patients with IXT. However, TEC may be an independent phenomenon with motor alignment, stereopsis, and pupil reflex pathway in patients with IXT.

Comparison of Antioxidant Properties of Dehydrolutein with Lutein and Zeaxanthin, and their Effects on Cultured Retinal Pigment Epithelial Cells

Dehydrolutein accumulates in substantial concentrations in the retina. The aim of this study was to compare antioxidant properties of dehydrolutein with other retinal carotenoids, lutein, and zeaxanthin, and their effects on ARPE-19 cells. The time-resolved detection of characteristic singlet oxygen phosphorescence was used to compare the singlet oxygen quenching rate constants of dehydrolutein, lutein, and zeaxanthin. The effects of these carotenoids on photosensitized oxidation were tested in liposomes, where photo-oxidation was induced by light in the presence of photosensitizers, and monitored by oximetry. To compare the uptake of dehydrolutein, lutein, and zeaxanthin, ARPE-19 cells were incubated with carotenoids for up to 19 days, and carotenoid contents were determined by spectrophotometry in cell extracts. To investigate the effects of carotenoids on photocytotoxicity, cells were exposed to light in the presence of rose bengal or all-trans-retinal. The results demonstrate that the rate constants for singlet oxygen quenching are 0.77 × 1010, 0.55 × 1010, and 1.23 × 1010 M−1s−1 for dehydrolutein, lutein, and zeaxanthin, respectively. Overall, dehydrolutein is similar to lutein or zeaxanthin in the protection of lipids against photosensitized oxidation. ARPE-19 cells accumulate substantial amounts of both zeaxanthin and lutein, but no detectable amounts of dehydrolutein. Cells pre-incubated with carotenoids are equally susceptible to photosensitized damage as cells without carotenoids. Carotenoids provided to cells together with the extracellular photosensitizers offer partial protection against photodamage. In conclusion, the antioxidant properties of dehydrolutein are similar to lutein and zeaxanthin. The mechanism responsible for its lack of accumulation in ARPE-19 cells deserves further investigation.

Energy transfer from high electronic levels of sensitizer molecules in bacterial solutions

The population dynamics of different energy states of sensitizer molecules under intense laser irradiation was studied taking account of triplet-triplet absorption and intersystem crossing between highly excited states. It is shown which quantum states are predominantly populated under the given irradiation conditions. It was found that the efficiency of energy transfer from high electronic levels of xanthene dyes in the media containing Escherichia coli or Bacillus subtilis bacteria is very low and this bacteria inactivation channel can be ignored when describing the mechanisms of damage to pathogenic microorganisms in the presence of photosensitizers.

A high-efficiency dye-sensitized Pt(II) decorated metal-organic cage for visible-light-driven hydrogen production

Platinum (Pt) complexes have been tremendously exploited as efficient catalysts for producing hydrogen from water due to their high work function and redox potential, yet maximum utilization remains challenging. Herein, we have synthesized and characterized a novel Zr-Bpydc-PtCl2 MOCs material by immobilization a platinum complex in 2,2'-bipyridyl-5,5'-dicarboxylic acid-based metal-organic cages (MOCs) for the first time. In the presence of photosensitizer (Rhodamine B), the functionalized Zr-Bpydc-PtCl2 MOCs exhibits good stability and a high photocatalytic H2 evolution rate (10,466 μmol g−1 h−1) in aqueous solution, which are 6 times of Bpy-PtCl2 and 1.8 times of Bpydc-PtCl2 under visible light irradiation (λ > 420 nm), respectively. Compared with reference experiments, the good performance of Zr-Bpydc-PtCl2 MOCs indicated that integrating catalyst molecules into MOCs is a promising approach for stabilizing the catalytic center and improving the photocatalytic efficiency of H2 production in water.

Construction of pH/glutathione responsive chitosan nanoparticles by a self-assembly/self-crosslinking method for photodynamic therapy

A novel pH/glutathione (GSH) multi-responsive chitosan nanoparticles (NPs) material has been successfully designed and prepared by a self-assembly/self-crosslinking method for photodynamic therapy (PDT), which overcomes the shortcomings of traditional photosensitizer carriers, such as poor chemical stability, low loading efficiency and single-responsive photosensitizer release. Amphiphilic sulfhydryl chitosan (SA-CS-NAC) is first prepared by modifying chitosan (CS) with stearic acid (SA) and N-acetyl-L-cysteine (NAC), and then subject to self-assembly and self-crosslinking in the presence of photosensitizer, indocyanine green (ICG), to form the ICG-loaded amphiphilic sulfhydryl chitosan nanoparticles (SA-CS-NAC@ICG NPs). The ICG entrapment efficiency and loading efficiency of the NPs are found to be 95.2% and 27.6%, respectively. The multi-responsive ICG release of the NPs to the low pH and high GSH content of the microenvironment in tumor cells is successfully achieved. Under the laser irradiation, the SA-CS-NAC@ICG NPs produce the amount of reactive oxygen species (ROS) twice of that generated by free ICG under the same conditions. The in vitro cell experiment confirmed the strong cellular uptake ability, low biotoxicity and good tumor inhibition of the NPs. Our work has provided a new strategy for the targeted photosensitizer delivery for PDT.

Generation of hydroxyl radicals during photodegradation of chloroacetic acids by 254 nm ultraviolet: A special degradation process revealed by a holistic radical determination methodology

Upon ultraviolet (UV) irradiation, aqueous contaminants may undergo direct and/or indirect photolysis. Direct photolysis refers to transformation of contaminants by UV photon, and indirect photolysis refers to degradation of contaminants by UV-induced reactive species in the presence of photosensitizers. Because hydroxyl radical (•OH) was unexpectedly observed during chloroacetic acids photolysis without using photosensitizer, a question arises regarding whether direct photolysis-induced indirect photolysis (DPIP) was present and how it originated and evolved along the process. To answer these questions, this study employed multiple different yet complementary •OH detection approaches (i.e., probe, scavenger, electron paramagnetic resonance, and hydroxylation products) to prove the presence and role of •OH. Given that hydrogen peroxide (H2O2) was produced only in oxygenated water but not in deoxygenated water, we revealed that •OH was mainly generated by reduced oxygen. Meanwhile, several photolysis products like formate, glycolic acid, and glyoxylic acid were able to yield H2O2 too, suggesting that they can all trigger formation of •OH under 254 nm UV. In addition to evidences of DPIP phenomenon, this study is also novel in demonstrating a holistic methodology to prove and identify the presence and sources of radicals, which might help enhance understandings of UV processes.

COMBINED EFFECT OF REACTIVE OXYGEN FORMS AND SHUNGITE ON THE GROWTH AND DEVELOPMENT OF CYANOBACTERIA

It has been shown that hydrogen peroxide, singlet oxygen and shungite affect the development of the population of cyanobacteria Anabaena variabilis and Synechocystis sp. PCC 6803 in different directions. The growth of cyanobacteria culture slows down in the presence of photosensitizer and hydrogen peroxide. In this case, the number of cells depends on the amount of shungite in the environment. Cyanobacteria Anabaena variabilis and Synechocystis sp. PCC 6803 grow better in the presence of 10 g/L shungite, but growth is suppressed at 100 g/L. Shungite at 10 g/L protectes cultures from the toxic effects of Bengal pink and hydrogen peroxide, which was determined by the level of photosynthesis efficiency and cell amounts. The growth of Anabaena variabilis (in terms of optical density at 680 nm) has been found to slow down in the presence of only hydrogen peroxide relative to the control. The growth of Anabaena variabilis in the presence of shungite and hydrogen peroxide is restored to the level of control samples. The number of cyanobacterium Synechocystis sp. PCC 6803 cells slows down significantly in the presence of singlet oxygen. Being combined with singlet oxygen, shungite partially inactivates the action of Bengal pink. At the end of the experiment, the growth of the culture is restored to 60% compared to the control. A similar relationship is observed when evaluating the effectiveness of photosynthesis of cyanobacteria Anabaena variabilis and Synechocystis sp. PCC 6803. Thus, singlet oxygen is more toxic than hydrogen peroxide. This may be due to different mechanisms of action of hydrogen peroxide and singlet oxygen on cyanobacteria growth. Depending on the content in the water, shungite can stimulate or inhibit the growth of cyanobacteria cells, inactivate the action of a toxicant.

Single Cobalt Atom Anchored Black Phosphorous Nanosheets as an Effective Cocatalyst Promotes Photocatalysis

AbstractExploring novel cocatalysts with sufficient active sites and rapid photogenerated carrier separation remains challenge for boosting photocatalytic reactions. Recently, two‐dimensional (2D) black phosphorus (BP) has been developed and recognized to be an ideal platform for anchoring metal ions through lone pair electrons. Herein, we propose a new structure that cobalt atomically dispersed on BP nanosheets (BP−Co), and apply it as cocatalyst for photocatalytic H2 evolution and CO2 reduction under visible light (&gt;420 nm) irradiation. Both scanning transmission electron microscope and X‐ray absorption near edge structure verified the existence of phosphorous‐coordinated Co sites. The interaction between Co and P brings greatly improvement on photocatalytic activities, and 18‐fold enhancement can be achieved on CdS when taking BP−Co as a noble‐metal‐free cocatalyst for H2 evolution, which is higher than that of Pt under the same conditions. Besides, BP−Co can also be used as an effective cocatalyst to promote photocatalytic CO2 reduction in the presence of photosensitizer [Ru(2, 2’‐bipyridy)3]Cl2 with a CO evolution rate of 88.6 μmol h−1, superior to those obtained from the state‐of‐the‐art cocatalysts. It is anticipated that the current work might provide basic understanding as well as new opportunities on 2D BP nanosheets for versatile photocatalytic reactions.

Human alpha and beta herpesviruses and cancer: passengers or foes?

Based on seroepidemiological studies, human herpes simplex virus types 1 and 2 (HSV-1, HSV-2) are put in relation with a number of cancer diseases; however, they do not appear to play a direct role, being only considered cofactors. Their ability to transform the cells in vitro could be demonstrated experimentally by removing their high lytic ability by a certain dose of UV radiation or by photoinactivation in the presence of photosensitizers, such as neutral red or methylene blue, or culturing under conditions suppressing their lytic activity. However, recent studies indicate that UV irradiated or photoinactivated HSV-1 and HSV-2, able to transform non-transformed cells, behave differently in transformed cells suppressing their transformed phenotype. Furthermore, both transforming and transformed phenotype suppressing activities are pertaining only to non-syncytial virus strains. There are some proposed mechanisms explaining their transforming activity. According to the "hit and run" mechanism, viral DNA induces only initiation of transformation by interacting with cellular DNA bringing about mutations and epigenetic changes and is no longer involved in other processes of neoplastic progression. According to the "hijacking" mechanism, virus products in infected cells may activate signalling pathways and thus induce uncontrolled proliferation. Such a product is e.g. a product of HSV-2 gene designated ICP10 that encodes an oncoprotein RR1PK that activates the Ras pathway. In two cases of cancer, in the case of serous ovarian carcinoma and in some prostate tumours, virus-encoded microRNAs (miRNAs) were detected as a possible cofactor in tumorigenesis. And, recently described herpes virus-associated growth factors with transforming and transformation repressing activity might be considered important factors playing a role in tumour formation. And finally, there is a number of evidence that HSV-2 may increase the risk of cervical cancer after infection with human papillomaviruses. A similar situation is with human cytomegalovirus; however, here, a novel mechanism named oncomodulation has been proposed. Oncomodulation means that HCMV infects tumour cells and modulates their malignant properties without having a direct effect on cell transformation.