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The absorption of the nanocomposites consisting of cir-coronene graphene quantum dot (GQD) and tetraphenylporphyrin (TPP) as a sensitizer of the solar cell is investigated by using the first-principles density functional theory (DFT) and the time-dependent DFT. The structures of the separate GQD, TPP, and their nanocomposites are optimized by hybrid DFT. The energy stability of the obtained structures is confirmed by the frequency analysis. The optical absorptions of the structures are calculated with the time-dependent DFT. The obvious absorption additivity of the nanocomposites is observed. The feasibility of the nanocomposites as the sensitizers of solar cells is examined by the conduction band minimum of TiO 2 and the lowest unoccupied molecular orbitals of the nanocomposites. The GQD-3TPPs are identified as the favorable candidate of a sensitizer of solar cell because of the most enhanced in optical absorption, obvious charge spatial separation, suitable LUMO energy levels and the driving force for electron transfer, and the low recombination rate of electron and hole.

The advent of nanomedicine requires novel delivery vehicles to actively target their site of action. Here, we demonstrate the development of lung-targeting drug-loaded liposomes and their efficacy, specificity and safety. Our study focuses on glucocorticoids methylprednisolone (MPS), a commonly used drug to treat lung injuries. The steroidal molecule was loaded into functionalized nano-sterically stabilized unilamellar liposomes (NSSLs). Targeting functionality was performed through conjugation of surfactant protein A (SPANb) nanobodies to form MPS–NSSLs–SPANb. MPS–NSSLs–SPANb exhibited good size distribution, morphology, and encapsulation efficiency. Animal experiments demonstrated the high specificity of MPS–NSSLs–SPANb to the lung. Treatment with MPS–NSSLs–SPANb reduced the levels of TNF-α, IL-8, and TGF-β1 in rat bronchoalveolar lavage fluid and the expression of NK-κB in the lung tissues, thereby alleviating lung injuries and increasing rat survival. The nanobody functionalized nanoparticles demonstrate superior performance to treat lung injury when compared to that of antibody functionalized systems.

Acute lung injury (ALI), is a major cause of morbidity and mortality, which is routinely treated with the administration of systemic glucocorticoids. The current study investigated the distribution and therapeutic effect of a dexamethasone(DXM)-loaded immunoliposome (NLP) functionalized with pulmonary surfactant protein A (SP-A) antibody (SPA-DXM-NLP) in an animal model. DXM-NLP was prepared using film dispersion combined with extrusion techniques. SP-A antibody was used as the lung targeting agent. Tissue distribution of SPA-DXM-NLP was investigated in liver, spleen, kidney and lung tissue. The efficacy of SPA-DXM-NLP against lung injury was assessed in a rat model of bleomycin-induced acute lung injury. The SPA-DXM-NLP complex was successfully synthesized and the particles were stable at 4°C. Pulmonary dexamethasone levels were 40 times higher with SPA-DXM-NLP than conventional dexamethasone injection. Administration of SPA-DXM-NLP significantly attenuated lung injury and inflammation, decreased incidence of infection, and increased survival in animal models. The administration of SPA-DXM-NLP to animal models resulted in increased levels of DXM in the lungs, indicating active targeting. The efficacy against ALI of the immunoliposomes was shown to be superior to conventional dexamethasone administration. These results demonstrate the potential of actively targeted glucocorticoid therapy in the treatment of lung disease in clinical practice.

The lead-free perovskites derivatives of Cs3Sb2X9 (X = Cl, Br, I) have been synthesized, but their photocatalytic properties are not explored. To evaluate the feasibility for the visible light catalytic performance, we calculate the structural, electronic, optical and charge transfer properties of Cs3Sb2X9, based on the hybrid density functional theory of HSE06 with the projector augmented wave potential. The results show the decrease of band energy gaps and the redshift of absorption edges from X = Cl to I. The absolute potential of the valence band maximum and conduction band minimum is determined to justify the feasibility of the photocatalytic water splitting or CO2 reduction. The calculated carrier mobilities reveal that the high electron mobilities of Cs3Sb2I9 are beneficial to the reducing powers for hydrogen generation and CO2 reduction. The present results indicate that Cs3Sb2I9 is appropriate for the photocatalytic water splitting to produce hydrogen or the CO2 reduction driven by the visible light.

The influence of the O-doped behavior on the superhard Pmm2-BC2N is investigated by using the first-principles hybridization functional calculation. The mechanical stability and the thermal stability of all considered structures are examined by elastic constants and molecular dynamics simulations, respectively. Furthermore, the feasibility after the doping behavior is examined with the formation energy. The optical and mechanical properties of the pristine and the O-doped Pmm2-BC2N are calculated. The results demonstrate that all the O-doped structures are stable, and O@C-2 and O@N have lower formation energy, indicating that they are easier to be synthesized. It is found that the N substituted by O atom can obviously improve the absorption in the visible light range. The calculated Vickers hardness demonstrates all the considered structures are superhard. Especially, the O@N structure is a potential functional material with the satisfactory hardness and absorption in visible light range.

The effect of strain on the electronic and optical properties of ATaO 2 N (A = Ca, Sr and Ba) is investigated using the first-principles hybridization functional calculations. The electronic and optical properties under the strains of − 8 to  + 8% in (100) and (010) directions are investigated. The results demonstrate that the band energy gap, band edges, absorption, reflectivity, and refractive index are obviously affected by the strains. Moreover, the effects of strains in (100) direction on all the considered properties of ATaO 2 N are more obvious than those in (010) direction. The enhanced absorption in the visible light region is also found, which implies that ATaO 2 N can well respond to the visible light. The present findings could provide a helpful reference to design photoelectronic materials with ATaO 2 N by strain engineering.

Background Acinetobacter baumannii , a significant nosocomial pathogen, has evolved resistance to almost all conventional antimicrobial drugs. Bacteriophage therapy is a potential alternative treatment for multidrug-resistant bacterial infections. In this study, one lytic bacteriophage, ZZ1, which infects A. baumannii and has a broad host range, was selected for characterization. Results Phage ZZ1 and 3 of its natural hosts, A. baumanni clinical isolates AB09V, AB0902, and AB0901, are described in this study. The 3 strains have different sensitivities to ZZ1, but they have the same sensitivity to antibiotics. They are resistant to almost all of the antibiotics tested, except for polymyxin. Several aspects of the life cycle of ZZ1 were investigated using the sensitive strain AB09V under optimal growth conditions. ZZ1 is highly infectious with a short latent period (9 min) and a large burst size (200 PFU/cell). It exhibited the most powerful antibacterial activity at temperatures ranging from 35°C to 39°C. Moreover, when ZZ1 alone was incubated at different pHs and different temperatures, the phage was stable over a wide pH range (4 to 9) and at extreme temperatures (between 50°C and 60°C). ZZ1 possesses a 100-nm icosahedral head containing double-stranded DNA with a total length of 166,682 bp and a 120-nm long contractile tail. Morphologically, it could be classified as a member of the Myoviridae family and the Caudovirales order. Bioinformatic analysis of the phage whole genome sequence further suggested that ZZ1 was more likely to be a new member of the Myoviridae phages. Most of the predicted ORFs of the phage were similar to the predicted ORFs from other Acinetobacter phages. Conclusion The phage ZZ1 has a relatively broad lytic spectrum, high pH stability, strong heat resistance, and efficient antibacterial potential at body temperature. These characteristics greatly increase the utility of this phage as an antibacterial agent; thus, it should be further investigated.

Nanobody (Nb) is a promising vector for targeted drug delivery. This study aims to identify an Nb that can specifically target the lung by binding human pulmonary surfactant protein A (SP-A). Human lung frozen tissue sections were used for 3 rounds of biospanning of our previously constructed Nb library for rat SP-A to establish a sub-library of Nb, which specifically bound human lung tissues. Phage-ELISA was performed to screen the sub-library to identify Nb4, which specifically bound human SP-A. The binding affinity Kd of Nb4 to recombinant human SP-A was 7.48 × 10 −7 M. Nb4 (19 kDa) was stable at 30 °C–37 °C and pH 7.0–7.6 and specifically bound the SP-A in human lung tissue homogenates, human lung A549 cells, and human lung tissues, whereas didn’t react with human liver L-02 cells, kidney 293T cells, and human tissues from organs other than the lung. Nb4 accumulated in the lung of nude mice 5 minutes after a tail vein injection of Nb4 and was excreted 3 hours. Short-term exposure (one month) to Nb4 didn’t cause apparent liver and kidney toxicity in rats, whereas 3-month exposure resulted in mild liver and kidney injuries. Nb4 may be a promising vector to specifically deliver drugs to the lung.

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The birthrate following round spermatid injection (ROSI) remains low in current and evidence suggests that factors in the germinal vesicle (GV) cytoplasm and certain substances in the GV such as the nucleolus might be responsible for genomic reprogramming and embryonic development. However, little is known whether the reprogramming factors in GV oocyte cytoplasm and/or nucleolus in GV are beneficial to the reprogramming of round spermatids and development of ROSI embryos. Here, round spermatids were treated with GV cytolysates and injected this round spermatid alone or co-injected with GV oocyte nucleolus into mature metaphase II oocytes. Subsequent embryonic development was assessed morphologically and by Oct4 expression in blastocysts. There was no significant difference between experimental groups at the zygote to four-cell development stages. Blastocysts derived from oocytes which were injected with cytolysate treated-round spermatid alone or co-injected with nucleoli injection yielded 63.6% and 70.3% high quality embryos, respectively; comparable to blastocysts derived by intracytoplasmic sperm injection (ICSI), but higher than these oocytes which were co-injected with lysis buffer-treated round spermatids and nucleoli or injected with the lysis buffer-treated round spermatids alone. Furthermore, the proportion of live offspring resulting from oocytes which were co-injected with cytolysate treated-round spermatids and nucleoli or injected with cytolysate treated-round spermatids alone was higher than those were injected with lysis buffer treated-round spermaids, but comparable with the ICSI group. Our results demonstrate that factors from the GV cytoplasm improve round spermatid reprogramming, and while injection of the extra nucleolus does not obviously improve reprogramming its potential contribution, although which cannot be definitively excluded. Thus, some reprogramming factors are evidently present in GV oocyte cytoplasm and could significantly facilitate ROSI technology, while the nucleolus in GV seems also having a potential to improve reprogramming of round spermatids.