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Covalently closed circular (ccc) DNA is the template for hepatitis B virus (HBV) replication. The lack of small animal models for characterizing chronic HBV infection has hampered research progress in HBV pathogenesis and drug development. Here, we generated a spatiotemporally controlled recombinant cccDNA (rcccDNA) mouse model by combining Cre/loxP-mediated DNA recombination with the liver-specific "Tet-on/Cre" system. The mouse model harbors three transgenes: a single copy of the HBV genome (integrated at the Rosa26 locus, RHBV), H11-albumin-rtTA (spatiotemporal conditional module), and (tetO) 7 -Cre (tetracycline response element), and is named as RHTC mouse. By supplying the RHTC mice with doxycycline (DOX)-containing drinking water for two days, the animals generate rcccDNA in hepatocytes, and the rcccDNA supports active HBV gene expression and can maintain HBV viremia persistence for over 60 weeks. Persistent HBV gene expression induces intrahepatic inflammation, fibrosis, and dysplastic pathology, which closely mirrors the disease progression in clinical patients. Bepirovirsen, an antisense oligonucleotide (ASO) targeting all HBV RNA species, showed dose-dependent antiviral effects in the RHTC mouse model. The spatiotemporally controlled rcccDNA mouse is convenient and reliable, providing versatile small animal model for studying cccDNA-centric HBV biology as well as evaluating antiviral therapeutics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

High-performance perovskite solar cells have demonstrated commercial viability, but still face the risk of contamination from lead leakage and long-term stability problems caused by defects. Here, an organic small molecule (octafluoro-1,6-hexanediol diacrylate) is introduced into the perovskite film to form a polymer through in situ thermal crosslinking, of which the carbonyl group anchors the uncoordinated Pb 2+ of perovskite and reduces the leakage of lead, along with the -CF 2 - hydrophobic group protecting the Pb 2+ from water invasion. Additionally, the polymer passivates varieties of Pb-related and I-related defects through coordination and hydrogen bonding interactions, regulating the crystallization of perovskite film with reduced trap density, releasing lattice strain, and promoting carrier transport and extraction. The optimal efficiencies of polymer-incorporated devices are 24.76 % (0.09 cm 2 ) and 20.66 % (14 cm 2 ). More importantly, the storage stability, thermal stability, and operational stability have been significantly improved., (© 2023 Wiley-VCH GmbH.)

Hepatitis B virus (HBV) chronically infects approximately 300 million people worldwide, and permanently repressing transcription of covalently closed circular DNA (cccDNA), the episomal viral DNA reservoir, is an attractive approach toward curing HBV. However, the mechanism underlying cccDNA transcription is only partially understood. In this study, by illuminating cccDNA of wild-type HBV (HBV-WT) and transcriptionally inactive HBV that bears a deficient HBV X gene (HBV-ΔX), we found that the HBV-ΔX cccDNA more frequently colocalizes with promyelocytic leukemia (PML) bodies than that of HBV-WT cccDNA. A small interfering RNA (siRNA) screen targeting 91 PML body-related proteins identified SMC5-SMC6 localization factor 2 (SLF2) as a host restriction factor of cccDNA transcription, and subsequent studies showed that SLF2 mediates HBV cccDNA entrapment in PML bodies by interacting with the SMC5/6 complex. We further showed that the region of SLF2 comprising residues 590 to 710 interacts with and recruits the SMC5/6 complex to PML bodies, and the C-terminal domain of SLF2 containing this region is necessary for repression of cccDNA transcription. Our findings shed new light on cellular mechanisms that inhibit HBV infection and lend further support for targeting the HBx pathway to repress HBV activity. IMPORTANCE Chronic HBV infection remains a major public health problem worldwide. Current antiviral treatments rarely cure the infection, as they cannot clear the viral reservoir, cccDNA, in the nucleus. Therefore, permanently silencing HBV cccDNA transcription represents a promising approach for a cure of HBV infection. Our study provides new insights into the cellular mechanisms that restrict HBV infection, revealing the role of SLF2 in directing HBV cccDNA to PML bodies for transcriptional repression. These findings have important implications for the development of antiviral therapies against HBV., Competing Interests: The authors declare no conflict of interest.

Carbonyl functional materials as additives are extensively applied to reduce the defects density of the perovskite film. However, there is still a lack of comprehensive understanding for the effect of carbonyl additives to improve device performance. In this work, we systematically study the effect of carbonyl additive molecules on the passivation of defects in perovskite films. After a comprehensive investigation, the results confirm the importance of molecular dipole in amplifying the passivation effect of additive molecules. The additive with strong molecular dipole possesses the advantages of enhancing the efficiency and stability of perovskite solar cells (PSCs). After optimization, the companion efficiency of PSCs is 23.20 %, and it can maintain long-term stability under harsh conditions. Additionally, a large-area solar cell module-modified DLBA was 20.18 % (14 cm 2 ). This work provides an important reference for the selection and designing of efficient carbonyl additives., (© 2023 Wiley-VCH GmbH.)

All-inorganic perovskites are promising for solar cells owing to their potentially superior tolerance to environmental factors, as compared with their hybrid organic-inorganic counterparts. Over the past few years, all-inorganic perovskite solar cells (PSCs) have seen a dramatic improvement in certified power conversion efficiencies (PCEs), demonstrating their great potential for practical applications. Pb, Sn, and Ge are the most studied group IVA elements for perovskites. These group IVA cations share the same number of valence electrons and similarly exhibit the beneficial antibonding properties of lone-pair electrons when incorporated in the perovskite structure. Meanwhile, mixing these cations in all-inorganic perovskites provides opportunities for stabilizing the photoactive phase and tailoring the bandgap structure. In this mini-review, we analyze the structural and bandgap design principles for all-inorganic perovskites featuring mixed group IVA cations, discuss the updated progress in the corresponding PSCs, and finally provide perspectives on future research efforts faciliating the continued development of high-performance Pb-less and Pb-free all-inorganic PSCs.

Hepatitis B virus (HBV) infection remains a public health problem worldwide. Persistent HBV infection relies on active transcription of the covalently closed circular DNA (cccDNA) in hepatocytes, which is less understood at the single-cell level. In this study, we isolated primary human hepatocytes from liver-humanized FRG mice infected with HBV and examined cccDNA transcripts in single cells based on 5' end sequencing. Our 5' transcriptome sequencing (RNA-seq) analysis unambiguously assigns different viral transcripts with overlapping 3' sequences and quantitatively measures viral transcripts for structural genes (3.5 kb, 2.4 kb, and 2.1 kb) and the nonstructural X gene (0.7 kb and related) in single cells. We found that an infected cell either can generate all viral transcripts, signifying active transcription, or presents only transcripts from the X gene and its associated enhancer I domain and no structural gene transcripts. Results from cell infection assays with recombinant HBV show that nonproductive transcription of cccDNA can be activated by incoming virus through superinfection. Moreover, upon HBV infection, cccDNA apparently can be transcribed in the absence of HBx and produces HBx, needed for productive transcription of other viral genes. These results shed new light on cccDNA transcription at the single-cell level and provide insights useful for improving the treatment strategy against chronic HBV infection. IMPORTANCE Hepatitis B virus (HBV) infection can be effectively suppressed but rarely cured by available drugs. Chronic HBV infection is based on persistence of covalently closed circular DNA (cccDNA) and continuous infection and reinfection with HBV in the liver. Understanding transcriptional regulation of cccDNA will help to achieve permanent transcriptional silencing, i.e., functional cure of HBV. In our study, we found that an infected cell either can generate all viral transcripts, signifying active transcription, or presents only transcripts from the X gene and its associated enhancer I domain and no structural gene transcripts. The nonproductive transcription of cccDNA can be activated by incoming virus through superinfection. Upon an infection, cccDNA apparently can be transcribed in the absence of HBx to produce HBx, necessary for subsequent transcription of other HBV genes. Our studies shed new light on the mechanism of HBV infection and may have implications for a functional cure regimen for HBV.

An organic small molecule, 1-bromo-4-(methylsulfinyl)benzene (BBMS), was utilized to reduce the energy disorder of a Sn-Pb alloyed perovskite film via hydrogen bonding and coordination bonding interactions, and the resultant BBMS-treated device showed a high efficiency of over 22 % as well as outstanding long-term stability., (© 2022 Wiley-VCH GmbH.)

Molecular doping is an of significance approach to reduce defects density of perovskite and to improve interfacial charge extraction in perovskite solar cells. Here, we show a new strategy for chemical doping of perovskite via an organic small molecule, which features a fused tricyclic core, showing strong intermolecular π-Pb 2+ interactions with under-coordinated Pb 2+ in perovskite. This π-Pb 2+ interactions could reduce defects density of the perovskite and suppress the nonradiative recombination, which was also confirmed by the density functional theory calculations. In addition, this doping via π-Pb 2+ interactions could deepen the surface potential and downshift the work function of the doped perovskite film, facilitating the hole extraction to hole transport layer. As a result, the doped device showed high efficiency of 21.41 % with ignorable hysteresis. This strategy of fused tricyclic core-based doping provides a new perspective for the design of new organic materials to improve the device performance., (© 2021 Wiley-VCH GmbH.)

Perovskite solar cells (PSCs) emerging as a promising photovoltaic technology with high efficiency and low manufacturing cost have attracted the attention from all over the world. Both the efficiency and stability of PSCs have increased steadily in recent years, and the research on reducing lead leakage and developing eco-friendly lead-free perovskites pushes forward the commercialization of PSCs step by step. This review summarizes the main progress of PSCs in 2020 and 2021 from the aspects of efficiency, stability, perovskite-based tandem devices, and lead-free PSCs. Moreover, a brief discussion on the development of PSC modules and its challenges toward practical application is provided.

The hepatitis B virus (HBV) infects 257 million people worldwide. HBV infection requires establishment and persistence of covalently closed circular (ccc) DNA, a viral episome, in nucleus. Here, we study cccDNA spatial localization in the 3D host genome by using chromosome conformation capture-based sequencing analysis and fluorescence in situ hybridization (FISH). We show that transcriptionally inactive cccDNA is not randomly distributed in host nucleus. Rather, it is preferentially accumulated at specialized areas, including regions close to chromosome 19 (chr.19). Activation of the cccDNA is apparently associated with its re-localization, from a pre-established heterochromatin hub formed by 5 regions of chr.19 to transcriptionally active regions formed by chr.19 and nearby chromosomes including chr.16, 17, 20, and 22. This active versus inactive positioning at discrete regions of the host genome is primarily controlled by the viral HBx protein and by host factors including the structural maintenance of chromosomes protein 5/6 (SMC5/6) complex., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Hepatitis B virus (HBV) is a member of the Hepadnaviridae family and infects hepatocytes, leading to liver pathology in acutely and chronically infected individuals. Co-infection with Hepatitis D virus (HDV), which requires the surface proteins of HBV to replicate, can exacerbate this disease progression. Thus, the >250 million people living with chronic HBV infection, including 13 million co-infected with HDV, would significantly benefit from an effective and affordable curative treatment. Animal models are crucial to the development of innovative disease therapies, a paradigm repeated again and again throughout the fields of immunology, neurology, reproduction, and development. Unfortunately, HBV has a highly-restricted species tropism, infecting limited species including humans, chimpanzees, and treeshrews. The first experimentally controlled studies of HBV infection were following inoculation of human volunteers in 1942, which identified the transmissibility of hepatitis through serum transfer and led to the hypothesis that the etiological agent was viral. Subsequent research in chimpanzees (Desmyter et al., 1971; Lichter, 1969) and later in other species, such as the treeshrews (Walter et al., 1996; Yan et al., 1996), further confirmed the viral origin of hepatitis B. Shortly thereafter, HBV-like viral infections were identified in woodchucks (Summers et al., 1978; Werner et al., 1979) and ducks, and much of our understanding of HBV replication can be attributed to these important models. However, with the exodus of chimpanzees from research and the limited reagents and historical data for treeshrews and other understudied species, there remains an urgent need to identify physiologically relevant models of chronic HBV infection. While large strides have been made in generating such models, particularly over the past two decades, there is still no available model that faithfully recapitulates the immunity and pathogenesis of HBV infection. Here, we discuss recent advancements in the generation of murine and non-human primate (NHP) models of HBV/HDV infection., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Sodium taurocholate cotransporting polypeptide (NTCP) is a functional receptor for human hepatitis B virus (HBV) and its satellite virus Hepatitis D virus (HDV). Physiologically, NTCP is responsible for the majority of sodium-dependent bile acids uptake by hepatocytes. The p.Ser267Phe (S267F) variant of NTCP is a single nucleotide polymorphism (SNP) previously found to cause substantial loss of ability to support HBV and HDV infection and its taurocholic acid uptake function in vitro. Intriguingly, ten individuals were identified as S267F homozygotes in population studies of chronic hepatitis B (CHB) patients. In this study, we identified new HBV isolates from one homozygous S267F mutation carrier and confirmed new isolates also use wildtype-NTCP as a cellular receptor. Furthermore, we demonstrated S267F variant of NTCP, though inefficient, is still a functional receptor for HBV entry. This study advances our understanding of NTCP-mediated HBV infection., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Effective passivation and stabilization of both the inside and interface of a perovskite layer are crucial for perovskite solar cells (PSCs), in terms of efficiency, reproducibility, and stability. Here, the first formamidinium lead iodide (δ-FAPbI 3 ) polymorph passivated and stabilized MAPbI 3 PSCs are reported. This novel MAPbI 3 /δ-FAPbI 3 structure is realized via treating a mixed organic cation MA x FA 1- x PbI 3 perovskite film with methylamine (MA) gas. In addition to the morphology healing, MA gas can also induce the formation of δ-FAPbI 3 phase within the perovskite film. The in situ formed 1D δ-FAPbI 3 polymorph behaves like an organic scaffold that can passivate the trap state, tunnel contact, and restrict organic-cation diffusion. As a result, the device efficiency is easily boosted to 21%. Furthermore, the stability of the MAPbI 3 /δ-FAPbI 3 film is also obviously improved. This δ-FAPbI 3 phase passivation strategy opens up a new direction of perovskite structure modification for further improving stability without sacrificing efficiency., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Solution-processed perovskite (PSC) solar cells have achieved extremely high power conversion efficiencies (PCEs) over 20%, but practical application of this photovoltaic technology requires further advancements on both long-term stability and large-area device demonstration. Here, an additive-engineering strategy is developed to realize a facile and convenient fabrication method of large-area uniform perovskite films composed of large crystal size and low density of defects. The high crystalline quality of the perovskite is found to simultaneously enhance the PCE and the durability of PSCs. By using the simple and widely used methylammonium lead iodide (MAPbI 3 ), a certified PCE of 19.19% is achieved for devices with an aperture area of 1.025 cm 2 , and the high-performing devices can sustain over 80% of the initial PCE after 500 h of thermal aging at 85 °C, which are among the best results of MAPbI 3 -based PSCs so far., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We report herein the discovery of methylamine (CH3NH2) induced defect-healing (MIDH) of CH3NH3PbI3 perovskite thin films based on their ultrafast (seconds), reversible chemical reaction with CH3NH2 gas at room temperature. The key to this healing behavior is the formation and spreading of an intermediate CH3NH3PbI3⋅xCH3NH2 liquid phase during this unusual perovskite-gas interaction. We demonstrate the versatility and scalability of the MIDH process, and show dramatic enhancement in the performance of perovskite solar cells (PSCs) with MIDH. This study represents a new direction in the formation of defect-free films of hybrid perovskites., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To evaluate the safety, effectiveness and complications of serial invasive prenatal diagnostic techniques, and to investigate the prenatal diagnosis indication as well as to analyze the abnormal chromosomal karyotype., Methods: We retrospectively studied all patients from March 2005 to May 2012 who received amniocentesis and cordocentesis in the prenatal diagnosis center of Second Xiangya Hospital. The indication of the procedure, successful rate and complications were evaluated, and 25 abnormal chromosome nuclear types were analyzed., Results: A total of 669 patients received invasive prenatal diagnosis from March 2005 to May 2012 in Second Xiangya Hospital: 598 received amniocentesis and 71 cordocentesis carried out. Compared with the cordocentesis group, the amniocentesis group had higher achievement ratio (91.54% vs 100%, P<0.05), lower spontaneous abortion rate (1.41% vs 0.33%, P<0.05), fewer abnormal karyotypes (11.27% vs 2.84%, P<0.05) and lower expenditure (880 yuan vs 800 yuan, P<0.05). Positive screening, advanced maternal age, and ultrasonography abnormality were the top 3 indications of amniocentesis and cordocentesis. We found 25 abnormal karyotypes, including 6 cases of trisomy 21, 4 sex chromosomal abnormalities, 7 autosomal balanced translocations, 1 marker chromosome, and 7 mosaics., Conclusion: As a widely used invasive prenatal diagnosis, amniocentesis is safe and effective. The complications of cordocentesis are much higher than those of amniocentesis, which is not a proper routine procedure for prenatal diagnosis of abnormal karyotype. The analysis of karyotype not only can identify fetal chromosome abnormality, but also provide the scientific basis for pregnancy continuation, thus reducing the ratio of birth defect.

Objective: Reperfusion therapy for myocardial infarction is limited by a significant reocclusion rate and less optimal myocardial tissue perfusion due to excessive platelet accumulation and recruitment at the sites of vascular injury. We assessed the influence of a selective P2Y(12)-receptor antagonist (AR-C69931MX), in conjunction with thrombolytic therapy, on the prevention of platelet aggregation and thrombus formation., Methods and Results: A canine coronary electrolytic injury thrombosis model was used. Tissue-type plasminogen activator (t-PA; 1 mg/kg in phase I, 0.5 mg/kg in phase II in the AR-C69931MX group, and 1 mg/kg in the placebo group in phase I and II) was administered 30 minutes after thrombus formation; either saline or AR-C69931MX (4 micro g x kg(-1) x min(-1)) was given to all animals intravenously 10 minutes before t-PA administration for a total of 2 hours. All animals received heparin (80 U/kg) as an intravenous bolus followed by a continuous infusion of 17 U x kg(-1) x h(-1). Myocardial tissue perfusion was evaluated by use of the colored microsphere technique and real-time myocardial contrast echocardiography. The incidences of reocclusion and cyclic flow variation were significantly decreased in the AR-C69931MX group (P<0.05). Myocardial tissue flow with AR-C69931MX treatment improved significantly at 20 and 120 minutes after reflow, whereas tissue flow with placebo remained at a level similar to that during occlusion (P<0.05)., Conclusions: The adjunctive administration of AR-C69931MX blocked ADP-mediated platelet aggregation and recruitment and prevented platelet-mediated thrombosis, resulting in prolongation of reperfusion time and a decrease in reocclusion and cyclic flow variations. Importantly, myocardial tissue perfusion was significantly improved in the P2Y(12) antagonist group.

Background: Variation at the apolipoprotein E locus on chromosome 19 plays a role in more cases of Alzheimer's disease than does any other identified genetic determinant. We have previously reported the isoform-specific interaction of native human apolipoprotein E (APOE, gene; apoE, protein) epsilon 3 with the amyloid-ss peptide, Ass(1-40), the major component of the cerebral amyloid deposits that appear to cause Alzheimer's disease., Materials and Methods: In order to investigate the apoE: A beta interaction further, a modified assay was developed based on co-immunoprecipitation of the complex using an anti-apoE antibody (anti-apoE IP assay)., Results: Application of this assay demonstrated that the interaction of Ass(1-40) and apoE can be distinguished into two types: sodium dodecyl sulfate (SDS) -resistant and SDS-releasable. The SDS-resistant interaction between epsilon;3 and Ass(1-40) is apparently maximal at an Ass(1-40) concentration of approximately 75 micro M, and an Ass(1-40) /epsilon 3 molar ratio of about 250:1. The major apoE-isoform-specific difference in interaction with Ass(1-40) is the ability of Ass(1-40) to form SDS- resistant complexes with epsilon 3 but not with epsilon 4. Using the anti-apoE co-IP assay, we found that human cerebrospinal fluid (CSF) epsilon 3 can also form an SDS-resistant complex with Ass(1-40) but human CSF epsilon;4 cannot. However, when compared with apoE epsilon;3 collected from the conditioned medium of APOE epsilon 3-transfected cells, the competence of equal concentrations of CSF apoE epsilon 3 to form SDS-resistant complexes with Ass(1-40) is apparently diminished. A 1:1 mixture of CSF plus apoE epsilon 3-containing conditioned medium is associated with diminished Ass(1-40) /epsilon;3 complex formation to a greater extent than that observed when an identical volume of phosphate-buffered saline is added to apoE epsilon;3 medium., Conclusions: These results suggest the presence in CSF of factors that interfere with the formation of complexes between synthetic Ass(1-40) and apoE epsilon 3.