A Novel Non-Fullerene D-A Interface with Two Asymmetrical Electron Acceptors Facilitates Charge and Energy Transfer for Effective Carbon Dioxide Reduction.

Converting carbon dioxide (CO2 ) into high-value chemicals using solar energy remains a formidable challenge. In this study, the CSC@PM6:IDT6CN-M:IDT8CN-M non-fullerene small-molecule organic semiconductor is designed with highly efficient electron donor-acceptor (D-A) interface for photocatalytic reduction of CO2 . Atomic Force Microscope and Transmission Electron Microscope images confirmed the formation of an interpenetrating fibrillar network after combination of donor and acceptor. The CO yield from the CSC@PM6:IDT6CN-M:IDT8CN-M reached 1346 µmol g-1  h-1 , surpassing those of numerous reported inorganic photocatalysts. The D-A structure effectively facilitated charge separation to enable electrons transfer from the PM6 to IDT6CN-M:IDT8CN-M. Meanwhile, attributing to the dipole moments of the strong intermolecular interactions between IDT6CN-M and IDT8CN-M, the intermolecular forces are enhanced, and laminar stacking and π-π stacking are strengthened, thereby reinforcing energy transfer between acceptor molecules and significantly enhanced charge separation. Moreover, the strong internal electric field in the D-A interface enhanced the excited state lifetime of PM6:IDT6CN-M:IDT8CN-M. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis demonstrated that carboxylate (COOH*) is the predominant intermediate during CO2 reduction, and possible pathways of CO2 reduction to CO are deduced. This study presents a novel approach for designing materials with D-A interface to achieve high photocatalytic activity.

Strain Engineering of Cd0.5 Zn0.5 S Nanocrystal for Efficient Photocatalytic Hydrogen Evolution from Wasted Plastic.

The challenge of synthesizing nanocrystal photocatalysts with adjustable lattice strain for effective waste-to-energy conversion is addressed in this study. Cd0.5 Zn0.5 S (CZS) nanocrystals are synthesized by a simple solvothermal method, regulation of the ratio between N, N-dimethylformamide, and water solvent are shown to provoke expansion and contraction, inducing an adjustable lattice strain ranging from -1.2% to 5.6%. With the hydrolyzed wasted plastic as a sacrificial agent, the 5.6% lattice-strain CZS exhibited a robust hydrogen evolution activity of 1.09 mmol m-2  h-1 (13.83 mmol g-1  h-1 ), 4.5 times that of pristine CZS. Characterizations and density functional theory calculation demonstrated that lattice expansion increases the spatial distance between the valence band maximum and conduction band minimum, thus reducing carrier recombination and promoting charge transfer. Additionally, lattice expansion induces surface S vacancies and adsorbed OH groups, further enhancing redox reactions. This study focuses on the synchronous regulation of crystal structure, charge separation/transport, and surface reactions through lattice strain engineering, which providing a reference for the rational design of new photocatalysts for effective waste-to-energy conversion.

Biomass-Derived Carbon Quantum Dots Chemical Bonding with Sn-Doped Bi2O2CO3 Endowed Fast Carriers' Dynamics and Stabilized Oxygen Vacancies for Efficient Decontamination of Combined Pollutants.

Surface defects on photocatalysts could promote carrier separation and generate unsaturated sites for chemisorption and reactant activation. Nevertheless, the inactivation of oxygen vacancies (OVs) would deteriorate catalytic activity and limit the durability of defective materials. Herein, bagasse-derived carbon quantum dots (CQDs) are loaded on the Sn-doped Bi2O2CO3 (BOC) via hydrothermal procedure to create Bi─O─C chemical bonding at the interface, which not only provides efficient atomic-level interfacial electron channels for accelerating carriers transfer, but also enhances durability. The optimized Sn-BOC/CQDs-2 achieves the highest photocatalytic removal efficiencies for levofloxacin (LEV) (88.7%) and Cr (VI) (99.3%). The elimination efficiency for LEV and Cr (VI) from the Sn-BOC/CQDs-2 is maintained at 55.1% and 77.0% while the Sn-BOC is completely deactivated after four cycle tests. Furthermore, the key role of CQDs in stabilization of OVs is to replace OVs as the active center of H2O and O2 adsorption and activation, thereby preventing reactant molecules from occupying OVs. Based on theoretical calculations of the Fukui index and intermediates identification, three possible degradation pathways of LEV are inferred. This work provides new insight into improving the stability of defective photocatalysts.

Ability of volume measures of hydronephrosis to predict need for surgery and evaluate renal function in children with ureteropelvic junction obstruction.

OBJECTIVE: To explore the efficacy of quantitative renal volume measures on magnetic resonance urography images in predicting need for surgery among children with ureteropelvic junction obstruction and their ability to evaluate renal function. METHODS: A total of 88 cases of hydronephrosis in 50 patients were collected between 1 April 2018 and 31 March 2020, including 30 operated kidney and 58 unoperated kidney cases. Clinical data were collected, and quantitative analysis of magnetic resonance urography was performed. Renal volume, hydronephrosis volume and the volume ratio of hydronephrosis (hydronephrosis volume/renal volume) were measured and calculated. We analyzed the relationships between the above indices in the two groups and compared these with renal function. RESULTS: Compared with the unoperated kidney group, hydronephrosis volume, renal volume and hydronephrosis volume/renal volume of the operated kidney group increased significantly. Hydronephrosis volume (area under the curve 0.972, 95% confidence interval 0.943-1.000; P < 0.001) and hydronephrosis volume/renal volume (area under the curve 0.968, 95% confidence interval 0.939-0.998; P < 0.001) were superior to ultrasonography and renal function examination in predicting the probability of surgery, and their sensitivity values (hydronephrosis volume/renal volume: 96.67%; hydronephrosis volume: 93.33%) were higher than those of the renal function test (50%). There was a significant difference among different renal function groups in the pairwise comparison of hydronephrosis volume and hydronephrosis volume/renal volume (P < 0.05). CONCLUSION: Quantitative volume measures of hydronephrosis by magnetic resonance urography had a greater ability to predict need for surgery than ultrasonography and dynamic renal imaging, and it can be used as method by which to evaluate surgery. Hydronephrosis volume and hydronephrosis volume/renal volume have greater predictive ability, and play an important role in the deterioration of renal function.

3D-Stretched Film Ni3 S2 Nanosheet/Macromolecule Anthraquinone Derivative Polymers for Electrocatalytic Overall Water Splitting.

For the first time, a new polymer electrode AQS/S is prepared by compositing Ni3 S2 nanosheets and macromolecular anthraquinone derivative (AQD) supported on nickel foam with flying colors. The AQS/S exhibits high crystalline structure and abundant S defects. Density of state calculation shows that AQD has stable internal bonding and easy external bonding with metals, conducive to the dispersion of metal reaction sites, ensuring excellent activity and high stability. Under 1.0 m KOH solution, ultralow overpotentials of 62 and 133 mV at 10 mA cm-2 on AQS/S for hydrogen evolution reaction and on activated AQS/S (A-AQS/S) for oxygen evolution reaction, respectively, are achieved. 100 h chronopotentiometry and the cyclic voltammetry tests show that catalysts have high durability. The AQS/S‖A-AQS/S two-electrode system is also found to have good electrocatalytic activity for 1.43 V to get 10 mA cm-2  in overall water splitting, better than the state-of-the-art 20% Pt/C‖RuO2 combination.

Leydig-like cells derived from reprogrammed human foreskin fibroblasts by CRISPR/dCas9 increase the level of serum testosterone in castrated male rats.

In the past few years, Leydig cell (LC) transplantation has been regarded as an effective strategy for providing physiological patterns of testosterone in vivo. Recently, we have successfully converted human foreskin fibroblasts (HFFs) into functional Leydig-like cells (iLCs) in vitro by using the CRISPR/dCas9 system, which shows promising potential for seed cells. However, it is not known whether the reprogrammed iLCs can survive or restore serum testosterone levels in vivo. Therefore, in this study, we evaluate whether reprogrammed iLCs can restore the serum testosterone levels of castrated rats when they are transplanted into the fibrous capsule. We first developed the castrated Sprague Dawley rat model through bilateral orchiectomy and subsequently injected extracellular matrix gel containing transplanted cells into the fibrous capsule of castrated rats. Finally, we evaluated dynamic serum levels of testosterone and luteinizing hormone (LH) in castrated rats, the survival of implanted iLCs, and the expression levels of Leydig steroidogenic enzymes by immunofluorescence staining and Western blotting. Our results demonstrated that implanted iLCs could partially restore the serum testosterone level of castrated rats, weakly mimic the role of adult Leydig cells in the hypothalamic-pituitary-gonadal axis for a short period, and survive and secrete testosterone, through 6 weeks after transplantation. Therefore, this study may be valuable for treating male hypogonadism in the future.

Mitochondria transfer via tunneling nanotubes is an important mechanism by which CD133+ scattered tubular cells eliminate hypoxic tubular cell injury.

Renal CD133 + scattered tubular cells (STCs) have been regarded as progenitor-like cells in the kidney and participated in ischemic renal injury repair. However, the mechanism of this effect is not fully elucidated yet. The primary objective of this study was to investigate the hypothesis that the protective effect of CD133 + STCs depends on the transfer of mitochondria to injured tubular cells in vitro. In this study, renal ischemic reperfusion injury (IRI) rat model was established with one side kidney ischemic for 45 min and animals were sacrificed at 48 h after operation. Tubular cells were isolated and cultured in vitro, and then CD133 + STCs were selected from the cultured cells. Then, CD133 + STCs were co-cultured with CD133-tubular cells (TECs) to detect the tunneling nanotubes like structures, and the transfer of mitochondria from CD133 + STCs to injured tubular cells were detected by fluorescent imaging and flow cytometry. Further, cellular protective effects of CD133 + STCs were tested when cultured with TECs under hypoxic conditions. In results, renal CD133 + STCs were scattered throughout the normal kidney and increased upon ischemic injury. Nanotube formations were commonly found between CD133 + STCs and TECs, and the transfer of mitochondria was detected from CD133 + STCs to TECs. Further, CD133 + STCs exist significant anti-apoptosis and pro-proliferation effects for TECs under hypoxic culture conditions. Thus, this study was first described that renal CD133 + STCs could transfer mitochondria to injured TECs in vitro for its protective effects, which revealed an important novel mechanism for renal repair after ischemic injury.

Oct-4 Enhanced the Therapeutic Effects of Mesenchymal Stem Cell-Derived Extracellular Vesicles in Acute Kidney Injury.

BACKGROUND/AIMS: Acute kidney injury (AKI) is a common clinical condition that can lead to chronic kidney failure. Although mesenchymal stem cell-derived extracellular vesicles (MSC EVs) are regarded as a potent AKI treatment, the mechanisms underlying their beneficial effects remain unclear. Oct-4 may play an important role in tissue injury repair. We thus hypothesized that oct-4 overexpression might enhance the therapeutic effects of MSC EVs in AKI treatment. METHODS: Renal tubular epithelial cells were cultured in a low oxygen environment, then cocultured with MSC EVs or control medium for 48 h. BrdU and transferase-mediated dUTP nick-end labeling (TUNEL) staining were used to assess cell proliferation and apoptosis. Mice subjected to ischemia reperfusion were randomly divided into 4 groups, then injected with either phosphate-buffered saline (vehicle), EVs, EVs overexpressing oct-4 (EVs+Oct-4), and EVs not expressing Oct-4 (EVs-Oct-4). Blood creatinine (CREA) and urine nitrone levels were assessed 48 h and 2 weeks after injection. After ischemia reperfusion, renal tissues from each group were stained with TUNEL and proliferating cell nuclear antigen (PCNA) to determine the degree of apoptosis and proliferation. Masson trichrome staining was used to evaluate renal fibrosis progression. Snail gene expression was assessed using polymerase chain reaction (PCR). RESULTS: At 48 h after hypoxic treatment, TUNEL and BrdU staining indicated that the EVs+Oct-4 group had the least apoptosis and the most proliferation, respectively. Treatment with EVs overexpressing Oct-4 significantly decreased serum Crea and blood urea nitrogen levels and rescued kidney fibrosis, as indicated by the low proportion of Masson staining, high number of PCNA-positive cells, and low number of TUNEL-positive cells. PCR analysis indicated that Snail was most upregulated in the vehicle group and least upregulated in the EVs+Oct-4 group. CONCLUSIONS: MSC EVs had a pronounced therapeutic effect on ischemic reperfusion injury-related AKI, and Oct-4 overexpression enhanced these therapeutic effects. Our results may inspire a new direction for AKI treatment with MSC EVs.

CRISPR/dCas9-mediated activation of multiple endogenous target genes directly converts human foreskin fibroblasts into Leydig-like cells.

Recently, Leydig cell (LC) transplantation has been revealed as a promising strategy for treating male hypogonadism; however, the key problem restricting the application of LC transplantation is a severe lack of seed cells. It seems that targeted activation of endogenous genes may provide a potential alternative. Therefore, the aim of this study was to determine whether targeted activation of Nr5a1, Gata4 and Dmrt1 (NGD) via the CRISPR/dCas9 synergistic activation mediator system could convert human foreskin fibroblasts (HFFs) into functional Leydig-like cells. We first constructed the stable Hsd3b-dCas9-MPH-HFF cell line using the Hsd3b-EGFP, dCas9-VP64 and MS2-P65-HSF1 lentiviral vectors and then infected it with single guide RNAs. Next, we evaluated the reprogrammed cells for their reprogramming efficiency, testosterone production characteristics and expression levels of Leydig steroidogenic markers by quantitative real-time polymerase chain reaction or Western blotting. Our results showed that the reprogramming efficiency was close to 10% and that the reprogrammed Leydig-like cells secreted testosterone rapidly and, more importantly, responded effectively to stimulation with human chorionic gonadotropin and expressed Leydig steroidogenic markers. Our findings demonstrate that simultaneous targeted activation of the endogenous NGD genes directly reprograms HFFs into functional Leydig-like cells, providing an innovative technology that may have promising potential for the treatment of male androgen deficiency diseases.

Conversion of human fibroblasts into functional Leydig-like cells by small molecules and a single factor.

Reprogramming fibroblasts into Leydig cells (LCs) offers a promising source for cell-based therapy for male hypogonadism. Recently, it has been achieved by forced expression of multiple transcription factors (TFs). However, for ultimate safe and convenient application, small molecules would be a revolutionary and desirable method to reduce or eliminate the genetic manipulations. Here, we report a defined small-molecule cocktail that enables the highly efficient conversion of human fibroblasts into functional LCs with only one transcription factor. These induced cells resembled human LCs with respect to morphology, marker gene expression and secretary function of testosterone. This study lays a foundation for future pharmacological reprogramming and provides a unique venue for investigating mechanisms underlying reprogramming.

Properties and Applications of Extremozymes from Deep-Sea Extremophilic Microorganisms: A Mini Review.

The deep sea, which is defined as sea water below a depth of 1000 m, is one of the largest biomes on the Earth, and is recognised as an extreme environment due to its range of challenging physical parameters, such as pressure, salinity, temperature, chemicals and metals (such as hydrogen sulphide, copper and arsenic). For surviving in such extreme conditions, deep-sea extremophilic microorganisms employ a variety of adaptive strategies, such as the production of extremozymes, which exhibit outstanding thermal or cold adaptability, salt tolerance and/or pressure tolerance. Owing to their great stability, deep-sea extremozymes have numerous potential applications in a wide range of industries, such as the agricultural, food, chemical, pharmaceutical and biotechnological sectors. This enormous economic potential combined with recent advances in sampling and molecular and omics technologies has led to the emergence of research regarding deep-sea extremozymes and their primary applications in recent decades. In the present review, we introduced recent advances in research regarding deep-sea extremophiles and the enzymes they produce and discussed their potential industrial applications, with special emphasis on thermophilic, psychrophilic, halophilic and piezophilic enzymes.

Chlorinated Azaphilone Pigments with Antimicrobial and Cytotoxic Activities Isolated from the Deep Sea Derived Fungus Chaetomium sp. NA-S01-R1.

Four novel compounds, chaephilone C (1), chaetoviridides A-C (2-4), were obtained from the culture of a deep sea derived fungus Chaetomium sp. NA-S01-R1, together with four known compounds-chaetoviridin A (5), chaetoviridine E (6), chaetomugilin D (7) and cochliodone A (8). Their structures, including absolute configurations, were assigned based on NMR, MS and time-dependent density functional theory (TD-DFT) ECD calculations. A plausible biogenetic pathway for compounds 1-3 was proposed. Compounds 2 and 3 exhibited antibacterial activities against Vibrio rotiferianus and Vibrio vulnificus. Compounds 1, 3 and 4 displayed similar anti-methicillin resistant Staphylococcus aureus (anti-MRSA) activities in comparison to chloramphenicol. Compound 2 showed the most potent cytotoxic activities towards the Hep G2 cell and compounds 1 and 3 demonstrated relatively stronger cytotoxic activities than the other compounds against the HeLa cell.

Improved hydrogen production in the microbial electrolysis cell by inhibiting methanogenesis using ultraviolet irradiation.

Methanogenesis inhibition is essential for the improvement of hydrogen (H2) yield and energy recovery in the microbial electrolysis cell (MEC). In this study, ultraviolet (UV) irradiation was proposed as an efficient method for methanogenesis control in a single chamber MEC. With 30 cycles of operation with UV irradiation in the MEC, high H2 concentrations (>91%) were maintained, while without UV irradiation, CH4 concentrations increased significantly and reached up to 94%. In the MEC, H2 yields ranged from 2.87 ± 0.03 to 3.70 ± 0.11 mol H2/mol acetate with UV irradiation and from 3.78 ± 0.12 to 0.03 ± 0.004 mol H2/mol acetate without UV irradiation. Average energy efficiencies from the UV-irradiated MEC were 1.5 times of those without UV irradiation. Energy production from the MEC without UV irradiation was a negative energy yield process because of large amount of CH4 produced over time, which was mainly attributable to cathodic hydrogenotrophic methanogenesis. Our results clearly showed that UV irradiation could effectively inhibit methanogenesis and improve MEC performance to produce H2.

A Self-Assembled MOF-Escherichia Coli Hybrid System for Light-Driven Fuels and Valuable Chemicals Synthesis.

The development of semi-artificial photosynthetic systems, which integrate metal-organic frameworks (MOFs) with industrial microbial cell factories for light-driven synthesis of fuels and valuable chemicals, represents a highly promising avenue for both research advancements and practical applications. In this study, an MOF (PCN-222) utilizing racemic-(4-carboxyphenyl) porphyrin and zirconium chloride (ZrCl4) as primary constituents is synthesized. Employing a self-assembly process, a hybrid system is constructed, integrating engineered Escherichia coli (E. coli) to investigate light-driven hydrogen and lysine production. These results demonstrate that the light-irradiated biohybrid system efficiently produce H2 with a quantum efficiency of 0.75% under full spectrum illumination, the elevated intracellular reducing power NADPH is also observed. By optimizing the conditions, the biohybrid system achieves a maximum lysine production of 18.25 mg L-1, surpassing that of pure bacteria by 332%. Further investigations into interfacial electron transfer mechanisms reveals that PCN-222 efficiently captures light and facilitates the transfer of photo-generated electrons into E. coli cells. It is proposed that the interfacial energy transfer process is mediated by riboflavin, with facilitation by secreted small organic acids acting as hole scavengers for PCN-222. This study establishes a crucial foundation for future research into the light-driven biomanufacturing using E. coli-based hybrid systems.

Exploration of the mechanism of levofloxacin removal by N-doped-induced interfacial micro-electric field-activated persulfate.

The defects formed by N doping always coexist with pyrrole nitrogen (Po) and pyridine nitrogen (Pd), and the synergistic mechanisms of H2O2 production and PMS activation between the different Po: Pd are unknown. This paper synthesized MOF-derived carbon materials with different nitrogen-type ratios as cathode materials in an electro-Fenton system using precursors with different nitrogen-containing functional groups. Several catalysts with different Po: Pd ratios (0:4, 1:3, 2:2, 3:1, 4:0) were prepared, and the best catalyst for LEV degradation was FC-CN (Po: Pd=3:1). X-ray Photoelectron Spectroscopy (XPS) and density-functional theory (DFT) calculations show that the introduction of nitrogen creates an interfacial micro-electric field (IMEF) in the carbon layer and the metal, accelerates the electron transfer from the carbon layer to the Co atoms, and promotes cycling between the Fe3+/Co2+ redox pairs, with the electron transfer reaching a maximum at Po: Pd = 3:1. FC-CN (Po: Pd=3:1) achieved more than 95 % LEV degradation in 90 min at pH = 3-9, with a lower energy consumption of 0.11 kWh m-3 order-1. and the energy consumption of the catalyst for LEV degradation is lower than that of those catalysts reported. In addition, the degradation pathway of LEV was proposed based on UPLC-MS and Fukui function. This study offers some valuable information for the application of MOF derivatives.

Ultrathin layer TAFC on BiVO4 with ligand-to-metal charge transfer enhances built-in electric field for boosting photoelectrochemical water oxidation.

To reveal the mechanism of charge transfer between interfaces of BiVO4-based heterogeneous materials in photoelectrochemical water splitting system, the cocatalyst was grown in situ using tannic acid (TA) as a ligand and Fe and Co ions as metal centers (TAFC), and then uniformly and ultra-thinly coated on BiVO4 to form photoanodes. The results show that the BiVO4/TAFC achieves a superior photocurrent density (4.97 mA cm-2 at 1.23 VRHE). The charge separation and charge injection efficiencies were also significantly higher, 82.0 % and 78.9 %, respectively. From XPS, UPS, KPFM, and density functional theory calculations, Ligand-to-metal charge transfer (LMCT) acts as an electron transport highway in TAFC ultrathin layer to promote the concentration of electrons towards metal center, leading to an increase in the work function, which enhances the built-in electric field and further improves the charge transport. This study demonstrated that the LMCT pathway on TA-metal complexes enhances the built-in electric field in BiVO4/TAFC to promote charge transport and thus enhance water oxidation, providing a new understanding of the performance improvement mechanism for the surface-modified composite photoanodes.

Anthraquinone-based polymer modified BiVO4 photoanode with strong electron-withdrawing functional groups for boasting photoelectrochemical water oxidation.

The photoelectrochemical (PEC) performance ofBiVO4 is limited by sluggish water oxidation kinetics and severe carrier recombination. Herein, a novel high-performance BiVO4/NiFe-NOAQ photoanode is prepared by a simple one-step hydrothermal method, using BiVO4 and 1-Nitroanthraquinone (NOAQ) as raw materials. The BiVO4/NiFe-NOAQ photoanode has an excellent photocurrent density of 5.675 mA cm-2 at 1.23 VRHE, which is 3.35 times higher than that of the pure BiVO4 (1.693 mA cm-2) photoanode. The BiVO4/NiFe-NOAQ shows a significant improvement in charge separation efficiency (86.12 %) and charge injection efficiency (87.86 %). The improvement is ascribable to the NiFe-NOAQ form a type II heterojunction with BiVO4 to inhibit carrier recombination. More importantly, the kinetic isotope experiment suggests that the proton-coupled electron transfer (PCET) process can enhance the charge transfer of BiVO4/NiFe-NOAQ. The contact angle measurements show that modifying functional groups enhanced the hydrophilicity of BiVO4/NiFe-NOAQ, which can further accelerate the PCET process. The XPS and PL results as well as the tauc plot indicate that the strong electron-withdrawing ability of -NO2 which can promote the extension of π conjugation, results in more π electron delocalization and produces more efficient active sites, thus achieving efficient photoelectrochemical water oxidation.

Diversity and potential host-interactions of viruses inhabiting deep-sea seamount sediments.

Seamounts are globally distributed across the oceans and form one of the major oceanic biomes. Here, we utilized combined analyses of bulk metagenome and virome to study viral communities in seamount sediments in the western Pacific Ocean. Phylogenetic analyses and the protein-sharing network demonstrate extensive diversity and previously unknown viral clades. Inference of virus-host linkages uncovers extensive interactions between viruses and dominant prokaryote lineages, and suggests that viruses play significant roles in carbon, sulfur, and nitrogen cycling by compensating or augmenting host metabolisms. Moreover, temperate viruses are predicted to be prevalent in seamount sediments, which tend to carry auxiliary metabolic genes for host survivability. Intriguingly, the geographical features of seamounts likely compromise the connectivity of viral communities and thus contribute to the high divergence of viral genetic spaces and populations across seamounts. Altogether, these findings provides knowledge essential for understanding the biogeography and ecological roles of viruses in globally widespread seamounts.

Inducing spin polarization via Co doping in the BiVO4 cell to enhance the built-in electric field for promotion of photocatalytic CO2 reduction.

The efficiency of CO2 photocatalytic reduction is severely limited by inefficient separation and sluggish transfer. In this study, spin polarization was induced and built-in electric field was strengthened via Co doping in the BiVO4 cell to boost photocatalytic CO2 reduction. Results showed that owing to the generation of spin-polarized electrons upon Co doping, carrier separation and photocurrent production of the Co-doped BiVO4 were enhanced. CO production during CO2 photocatalytic reduction from the Co-BiVO4 was 61.6 times of the BiVO4. Notably, application of an external magnetic field (100 mT) further boosted photocatalytic CO2 reduction from the Co-BiVO4, with 68.25 folds improvement of CO production compared to pristine BiVO4. The existence of a built-in electric field (IEF) was demonstrated through density functional theory (DFT) simulations and kelvin probe force microscopy (KPFM). Mechanism insights could be elucidated as follows: doping of magnetic Co into the BiVO4 resulted in increased the number of spin-polarized photo-excited carriers, and application of a magnetic field led to an augmentation of intrinsic electric field due to a dipole shift, thereby extending carrier lifetime and suppressing charges recombination. Additionally, HCOO- was a crucial intermediate in the process of CO2RR, and possible pathways for CO2 reduction were proposed. This study highlights the significance of built-in electric fields and the important role of spin polarization for promotion of photocatalytic CO2 reduction.

Small Molecule Cocktails Promote Fibroblast-to-Leydig-like Cell Conversion for Hypogonadism Therapy.

Male hypogonadism arises from the inadequate production of testosterone (T) by the testes, primarily due to Leydig cell (LC) dysfunction. Small molecules possess several advantages, including high cell permeability, ease of synthesis, standardization, and low effective concentration. Recent investigations have illuminated the potential of small molecule combinations to facilitate direct lineage reprogramming, removing the need for transgenes by modulating cellular signaling pathways and epigenetic modifications. In this study, we have identified a specific cocktail of small molecules, comprising forskolin, DAPT, purmorphamine, 8-Br-cAMP, 20α-hydroxycholesterol, and SAG, capable of promoting the conversion of fibroblasts into Leydig-like cells (LLCs). These LLCs expressed key genes involved in testosterone synthesis, such as Star, Cyp11a1, and Hsd3b1, and exhibited the ability to secrete testosterone in vitro. Furthermore, they successfully restored serum testosterone levels in testosterone-castrated mice in vivo. The small molecule cocktails also induced alterations in the epigenetic marks, specifically H3K4me3, and enhanced chromosomal accessibility on core steroidogenesis genes. This study presents a reliable methodology for generating Leydig-like seed cells that holds promise as a novel therapeutic approach for hypogonadism.